Question 1

A 42-year-old man comes to the physician with painful skin lesions.  The lesions developed on his neck, chest, and arms 1 week ago.  He also complains of fever, headache, malaise, and arthralgias.  Three weeks ago, he had an upper respiratory infection that resolved with over-the-counter medications.  The patient has no other medical problems and takes no medications.  He does not use tobacco or illicit drugs and drinks alcohol on social occasions.  He works as a cab driver.
His temperature is 38.2° C (100.8° F), blood pressure is 120/70 mm Hg, pulse is 88/min, and respirations are 14/min.  Physical examination is otherwise unremarkable.
Skin findings are shown in the photograph.

Laboratory studies show a leukocyte count of 14,000 cells/µL with 87% neutrophils.  He is started on oral clindamycin and sent home.
The patient returns for follow-up 3 days later with no improvement.  Blood cultures obtained on the initial visit show no growth.  Biopsy of the lesion shows a dense neutrophilic infiltrate in the dermis without vasculitis.  Gram and fungal stains are negative.
Which of the following is the most appropriate next step in management?

Accepted Answer

11ec193a_9783_b027_853d_ab33e2564dc5_MD0002_00 This patient's clinical presentation suggests Sweet syndrome (acute febrile neutrophilic dermatosis). Classic Sweet syndrome (most common) is associated with infections (usually 1-3 weeks after upper respiratory tract or gastrointestinal infections), inflammatory bowel disease, and pregnancy. Malignancy-associated Sweet syndrome occurs most commonly with hematologic malignancies but can also occur with solid tumors. Drug-induced Sweet syndrome is most commonly due to granulocyte colony-stimulating factor but can occur with other drugs. Patients typically present with abrupt onset of painful edematous papules, plaques, or nodules. These erythematous or violaceous lesions can be associated with pustules or central yellowish discoloration similar to target lesions. The lesions are located asymmetrically on the head, neck, and upper extremities. Pathergy (lesion development at cutaneous injury sites) can occur, even with minor trauma. Other findings include burning or tenderness without pruritus, fever > 38° C, and possible systemic symptoms (eg, arthralgias, myalgias, malaise, headache). Complete blood count typically shows neutrophilic leukocytosis. Skin biopsy shows dense neutrophilic infiltrate without leukocytoclastic vasculitis. Patients without preexisting malignancy or other associations (eg, inflammatory bowel disease, drug-related, prior infection) should undergo age-appropriate cancer screening. Mild Sweet syndrome (< 5% of body surface area involvement) usually responds to topical corticosteroids; extensive disease requires systemic glucocorticoids. (Choices B and D) This patient has no signs or symptoms of systemic infection or endocarditis such as bacteremia, new heart murmur, or heart failure. Echocardiogram or switching antibiotics is therefore not recommended. (Choice C) The classic butterfly rash of systemic lupus erythematosus appears as erythema and scaling over the cheeks and bridge of the nose with sparing of the nasolabial folds. Some patients develop discoid lesions. Discoid lupus erythematosus typically presents with photosensitive patches of various sizes that are erythematous and well-defined (Image). The lesions tend to heal with hair loss, skin atrophy, deep scarring, and peripheral hyperpigmentation. systemic lupus erythematosus (Image) peripheral hyperpigmentation (Choice E) Essential mixed cryoglobulinemia is associated with hepatitis C virus infection and presents with palpable purpura, arthralgias, renal disease (membranoproliferative glomerulonephritis), low serum complement, and neuropathy. Purpuric skin lesions usually occur in the lower extremities and may progress to necrosis and gangrene. Essential mixed cryoglobulinemia Educational objective: Sweet syndrome is an inflammatory disorder with abrupt onset of painful cutaneous papules, fever, neutrophilic leukocytosis, and dense neutrophilic infiltration on skin biopsy without signs of vasculitis. It may be associated with infections, inflammatory bowel disease, pregnancy, malignancy, or drugs. Treatment involves topical corticosteroids for mild disease and systemic glucocorticoids for more extensive disease. __________ References: Sweet's syndrome: retrospective study of clinical and histologic features of 44 cases from a tertiary care center. (http://www.ncbi.nlm.nih.gov/pubmed/21038541) Sweet's syndrome - a comprehensive review of an acute febrile neutrophilic dermatosis. (http://www.ncbi.nlm.nih.gov/pubmed/17655751)

Question 2

A 49-year-old woman comes to the physician for evaluation of a rash on her back and shoulders.  She initially noticed the rash nearly 2 years ago.  The rash began as a red scaly area that progressed from the shoulders to the neck region and upper back.  There was no pruritus, and the rash spontaneously resolved after a few days.  The patient has had a recurrence of the rash every 2-3 months since that time.
Skin examination (Image shown below) shows erythematous and scaly papules with crusted margins.  There is no drainage from the lesions or tenderness to palpation.  The remainder of her physical examination is normal.

Which of the following is the most likely diagnosis?

Accepted Answer

11ec193a_978d_7339_853d_c5d0614c491e_MD0002_00 This patient's clinical features suggest subacute cutaneous lupus erythematosus (SCLE). SCLE typically presents as a photosensitive rash (shoulders, forearms, neck, upper torso) with erythematous and slightly scaly papules that can coalesce into psoriasiform or annular patterns with crusted margins. SCLE is frequently associated with systemic lupus erythematosus (SLE) but is a distinct entity; about 50% of patients with SCLE will develop SLE, and 10% of patients with SLE will have concurrent SCLE. Unlike SLE, the rash of SCLE does not have a malar or discoid pattern. SCLE can be idiopathic or due to drugs (eg, antihypertensives, lipid-lowering agents, proton pump inhibitors, and antihistamines). Laboratory findings in SCLE include positive anti-Ro/SSA antibodies, normal complement levels and immune complexes, and no significant hematologic findings (cytopenias). Unlike SLE, patients with SCLE do not usually have a positive antinuclear antibody (ANA) test. Although renal disease is possible in SLE and SCLE, patients with SCLE do not usually develop serositis or neurologic disease. Diagnosis is typically made clinically but may require skin biopsy to exclude other diagnoses. Treatment involves topical corticosteroids, sun protection, and cessation of possible offending drugs. (Choice A) Nummular eczema is characterized by pruritic, ovoid lesions ranging from 1-10 cm. It initially appears as erythematous, exudative, or crusted patches and eventually evolves into scaly lesions with central clearing. Nummular eczema most commonly involves the legs and upper extremities. Nummular eczema (Choice B) Plaque psoriasis typically presents as symmetrical plaques involving the scalp, elbows, knees, and back. The plaques are usually erythematous with sharply defined borders. This patient's photosensitive distribution makes this less likely. Plaque psoriasis (Choice C) Seborrheic dermatitis causes pruritic and erythematous plaques with fine, loose, yellow, and greasy scales. It commonly affects areas with a high content of sebaceous glands, such as the scalp (dandruff), face, chest, and intertriginous areas. Seborrheic dermatitis (Choice E) Tinea corporis typically presents as pruritic, round, erythematous, scaly patches or plaques with progressing borders and a clearing center. However, this patient's recurrent, photosensitive pattern and absence of pruritus makes this less likely. Tinea corporis Educational objective: Subacute cutaneous lupus erythematosus is characterized by a photosensitive rash with small, erythematous, and slightly scaly papules that can coalesce into annular patterns with crusted margins. Patients usually have positive anti-Ro/SSA antibodies, normal complement levels, and no significant hematologic abnormalities. __________ References: Pathogenesis of subacute cutaneous lupus erythematosus. (http://www.ncbi.nlm.nih.gov/pubmed/18540991) Subacute cutaneous lupus erythematosus and its association with drugs: a population-based matched case-control study of 234 patients in Sweden. (http://www.ncbi.nlm.nih.gov/pubmed/22458771)

Question 3

A 45-year-old woman comes to the physician for a periodic health examination.  She has a pigmented lesion on her right leg that she first noticed a few years ago and would like to have checked.  The patient does not think that the mole has changed in appearance.  She has had some sunburn in the past.
The patient is fair skinned and has reddish-blond hair and hazel eyes.  Skin examination shows multiple cherry angiomata over her trunk and some on her upper extremities.  There is dense freckling over her shoulders and barely perceptible dense freckling over her cheeks.  There is a homogenous, well-demarcated, circular, light brown, and nonelevated lesion 5 mm in diameter over her right distal tibial area.  No border irregularity is seen under dermoscopy.
Which of the following is the best next step in management of this patient?

Accepted Answer

This patient's presentation is consistent with melanocytic nevi, common benign pigmented lesions found on the skin of most individuals. The coloration can be variable, ranging from tan to jet black. They tend to be < 6 mm in diameter and have a symmetrical and homogeneous surface with sharp borders. Nevi usually concentrate in sun-exposed areas. Suspicious nevus should be examined for the following clinical features of melanoma as the early superficial form can closely resemble nevi. melanocytic nevi < Asymmetry (if a lesion is bisected, one half is not identical to the other)Border irregularitiesColor variation (brown, red, black or blue/gray, and white)Diameter > 6 mmEvolving: lesion changing in size, shape, or color; new lesion Asymmetry (if a lesion is bisected, one half is not identical to the other) Border irregularities Color variation (brown, red, black or blue/gray, and white) Diameter > 6 mm Evolving: lesion changing in size, shape, or color; new lesion Lesions with a greater number of these criteria have a higher chance of being a melanoma. Melanomas are further classified as superficial spreading, lentigo maligna, acral lentiginous, and nodular. superficial spreading lentigo maligna acral lentiginous Lesions suspicious for malignancy should have excisional biopsy with a 1 to 2 mm rim of normal-appearing skin (Choice A, B, & D). The clinician should also examine other areas (eg, scalp, palms and soles, between the toes) for possible lesions. Once the diagnosis of melanocytic nevi has been established, these lesions require no treatment other than periodic observation. Most nevi remain benign throughout the patient's life and do not require prophylactic removal. Patients should receive periodic skin examinations and use adequate sun protection. (Choice E) Topical fluorouracil is used in both actinic keratosis and superficial basal cell carcinoma. Educational objective: Melanocytic nevi are benign pigmented lesions that are usually tan to jet black in color, tend to be < 6 mm in diameter, and present with a symmetric and homogeneous surface with sharp borders. Melanoma should be ruled out in all pigmented lesions. Melanocytic nevi usually require no treatment other than periodic observation as most remain benign. < __________ References: Biopsy for malignant melanoma-are we following the guidelines? (http://www.ncbi.nlm.nih.gov/pubmed/18492398) Early diagnosis of cutaneous melanoma: revisiting the ABCD criteria. (http://www.ncbi.nlm.nih.gov/pubmed/15585738) Systematic skin cancer screening in Northern Germany. (http://www.ncbi.nlm.nih.gov/pubmed/22074699)

Question 4

A 47-year-old man comes to the physician with a scaly rash on his face.  Two weeks ago, he went to an urgent care clinic and was treated with a topical corticosteroid and antifungal agent.  Despite consistent use of these agents, the rash has not improved.  He also has new areas on his arms and legs.  He reports that he feels constantly embarrassed by his condition.
The skin examination findings are shown in the photograph below.

Which of the following is the best next step in management of this patient?

Accepted Answer

11ec193a_9784_e8aa_853d_a7a163b3fe13_MD0002_00 Seborrheic dermatitis is a common inflammatory disease that affects areas with sebaceous glands such as the scalp (dandruff), face (eyebrows, nasolabial folds, external ear canal/posterior ear), chest, and intertriginous areas. This condition occurs in all age groups but is seen in increased frequency with Parkinson disease. It can also be the initial presentation of HIV in patients with CD4 counts < 400 cells/µL. Patients typically present with pruritic erythematous plaques with fine, loose, yellow, and greasy-looking scales. Seborrheic dermatitis tends to be more severe and extensive in HIV patients, especially those with CD4 < 200 cells/µL. HIV patients can develop lesions in unusual sites (eg, extremities) and may be resistant to topical corticosteroids and antifungals. This patient was treated appropriately for seborrheic dermatitis but was unresponsive and now requires HIV testing. (Choice A) The classic butterfly rash of systemic lupus erythematosus appears as erythema and scaling over the cheeks and bridge of the nose with sparing of the nasolabial folds. Some patients develop discoid lesions that appear as photosensitive, erythematous, and well defined and heal to cause hair loss, skin atrophy, deep scarring, and peripheral hyperpigmentation. systemic lupus erythematosus (Choice C) Topical metronidazole is the most frequently prescribed initial therapy for rosacea. Rosacea presents with facial erythema, telangiectasias, papules or pustules, and episodic flushing over the cheeks, nose, and chin. Flushing may be precipitated by heat, acute stress, medications, and other causes of rapid body temperature changes. rosacea (Choice D) Classic rash of secondary syphilis presents with diffuse maculopapular lesions that involve the trunk and extremities, including the palms and soles. Lesions are reddish-brown and may be pustular or nodular (but not vesicular). secondary syphilis (Choice E) Plaque psoriasis is frequently treated with topical corticosteroids and vitamin D analogs. Lesions are symmetrically distributed over the scalp and extensor surfaces such as elbows, knees, and trunk. Facial involvement is rare. Plaques appear as erythematous, sharply demarcated lesions covered with a silvery scale. Plaque psoriasis Educational objective: Seborrheic dermatitis that is severe and extensive should prompt testing for HIV. In this patient population, it can involve unusual sites (eg, extremities) and is often resistant to commonly prescribed therapy. Treatment includes antifungals and corticosteroids, often for a prolonged period. __________ References: Seborrheic dermatitis. (http://www.ncbi.nlm.nih.gov/pubmed/12956195) Seborrheic dermatitis in patients with acquired immunodeficiency syndrome. (http://www.ncbi.nlm.nih.gov/pubmed/2934444)

Question 5

A 42-year-old man complains of skin lesions on his legs for the last 6 weeks.  He has become concerned because they are enlarging rapidly, are painful, and have started to drain pus.  He has not had similar symptoms before.  The patient has no trauma to the area, fevers, or night sweats.  He takes analgesics for chronic low back pain and is on a lactose-free diet due to diarrhea.  The patient tries to be compliant with his diet but still has crampy abdominal pain and frequent bowel movements, occasionally at night.  He does not use intravenous drugs.
His vital signs are normal.  Skin examination is shown in the photograph.

Laboratory analysis shows an elevated C-reactive protein and erythrocyte sedimentation rate.  X-ray of both legs reveals no bony erosions or soft-tissue gas.
Which of the following is the most likely diagnosis?

Accepted Answer

11ec193a_9786_483c_853d_7be34eee4101_MD0002_00 This patient's presentation is consistent with pyoderma gangrenosum (PG), a rare neutrophilic, ulcerative skin disease. PG initially starts as a tender papule, pustule, or vesicle. Over time, it expands outward and begins to disintegrate centrally with noted purulence and a necrotic base. This leads to central ulceration with ragged and violaceous outer borders. PG can have a single or multiple lesions and appears most frequently on the trunk or lower extremities. In about 30% of cases, preceding trauma can induce or aggravate PG, a process known as pathergy. More than 50% of PG patients have an associated underlying systemic disorder such as inflammatory bowel disease (IBD), arthropathies (eg, rheumatoid arthritis), or hematologic conditions (eg, acute myeloid leukemia). PG can present before or at the time of diagnosis of these underlying diseases. This patient's combination of chronic back pain, crampy abdominal pain, frequent diarrhea, and elevated C-reactive protein and erythrocyte sedimentation rate strongly suggests spondyloarthropathy with IBD. PG is often a diagnosis of exclusion. Skin biopsy findings are nonspecific in PG but are usually required to exclude other similarly presenting conditions (eg, venous ulcers, panniculitis, cutaneous cancers). Mild and localized PG (few superficial lesions) should be treated with a high-potency topical corticosteroid or topical tacrolimus. Systemic glucocorticoids with or without cyclosporine are usually indicated for patients with extensive PG or failure to respond to local interventions. (Choice A) Erythema nodosum presents as tender, erythematous nodules/plaques due to a delayed hypersensitivity to antigens in drugs or other conditions (eg, streptococcal infection). Although these lesions can be associated with IBD, they do not ulcerate and typically resolve after 2-8 weeks without scarring. Erythema nodosum (Choice B) Leukocytoclastic vasculitis is a hypersensitivity vasculitis and usually presents with palpable purpura and systemic symptoms (eg, fever, arthralgias, diarrhea). (Choice C) Scrofuloderma (seen in both Mycobacterium tuberculosis and M bovis infections) usually presents as firm, painless, subcutaneous, and red-brown nodules. The skin lesions are typically due to direct extension of a deep structure (commonly lymph node) infection into the overlying skin. They can eventually ulcerate and form draining sinus tracts with purulent and watery material. However, they are less common with current effective tuberculosis therapies. (Choice D) Necrobiosis lipoidica presents with asymptomatic skin lesions that appear as indurated, yellowish plaques with central atrophy and are most often located on the shins. It is an inflammatory skin disorder found most commonly in diabetics. Necrobiosis lipoidica Educational objective: Pyoderma gangrenosum is a rapidly progressing, painful ulcer with a purulent base and violaceous borders. More than 50% of patients have associated systemic disease (eg, inflammatory bowel disease). Treatment usually requires local or systemic corticosteroids. __________ References: Etiology and management of pyoderma gangrenosum: a comprehensive review. (http://www.ncbi.nlm.nih.gov/pubmed/22356259) Pyoderma gangrenosum. A comparison of typical and atypical forms with an emphasis on time to remission. Case review of 86 patients from 2 institutions. (http://www.ncbi.nlm.nih.gov/pubmed/10670408) Skin ulcers misdiagnosed as pyoderma gangrenosum. (http://www.ncbi.nlm.nih.gov/pubmed/12409543)

Question 6

A 54-year-old woman comes to the office for evaluation of a rash on her face.  She initially developed facial flushing and redness 8 months ago and has had intermittent, progressive symptoms since then.  She has also had a burning sensation in the cheeks.  The rash worsens with sun exposure and spicy foods.  The patient has traveled extensively the past few months and has been outdoors more than usual.  She has no history of tobacco or alcohol use.
Vital signs are within normal limits.  Skin examination is shown in the exhibit.  The remainder of the physical examination is normal.
Which of the following is the best next step in management of this patient's rash?

Accepted Answer

11ec193a_978a_65f3_853d_9ba075d703d3_MD0002_00 This patient's rash is consistent with erythematotelangiectatic rosacea, which typically occurs in light-skinned individuals (women > men) age >30. Subtypes of rosacea include erythematotelangiectatic, papulopustular, phymatous, and ocular. The etiology is not fully understood but may relate to a chronic inflammatory reaction to cutaneous microorganisms, ultraviolet light damage, or vasomotor dysfunction. Common triggers include sun exposure, extreme temperatures (cold or heat), spicy foods, alcohol, and exercise. papulopustular phymatous Erythematotelangiectatic rosacea is characterized by chronic erythema in the nose and medial cheeks (including the nasolabial folds), facial flushing, telangiectasias, roughness or scaling, sensitive skin with burning, and occasionally facial edema. Patients with mild to moderate symptoms (such as this patient) often improve with gentle cleansers, sunscreen, and avoidance of triggers that cause flushing (eg, hot or spicy foods, alcohol, temperature extremes, emotional distress). Patients not responding to conservative therapy may benefit from laser/pulsed light therapy or topical brimonidine (Choice D). (Choice A) Antinuclear antibodies are used to screen for cutaneous lupus erythematosus, which can cause a facial rash similar to rosacea. However, the malar rash in cutaneous lupus spares the nasolabial folds. Although it can occur at any age, most patients develop symptoms at age 15-44. cutaneous lupus erythematosus (Choice B) The diagnosis of rosacea is usually based on clinical findings. Skin biopsy is occasionally helpful if an alternate diagnosis is being considered but is rarely necessary. (Choice E) Topical corticosteroids can treat seborrheic dermatitis, which can affect the lateral sides of the nose, nasolabial folds, eyebrows, and scalp. The rash is often erythematous but usually has oily scaling and pruritus. In contrast to rosacea, seborrheic dermatitis is not associated with facial flushing. seborrheic dermatitis Educational objective: Erythematotelangiectatic rosacea is characterized by erythema in the nose and medial cheeks, flushing, telangiectasias, and burning sensations. Initial management includes mild cleansers, sunscreen, and avoidance of triggers that cause flushing (eg, hot or spicy foods, alcohol, temperature extremes, emotional distress). __________ References: Rosacea management. (http://www.ncbi.nlm.nih.gov/pubmed/27843919) Once-daily topical brimonidine tartrate gel 0•5% is a novel treatment for moderate to severe facial erythema of rosacea: results of two multicenter, randomized and vehicle-controlled studies. (http://www.ncbi.nlm.nih.gov/pubmed/22050040)

Question 7

A 40-year-old man comes to the physician for evaluation of a rash involving his knees and shins.  The rash has been present for 9 months with mild itching that worsens in winter.  No other areas of the patient's body are involved, and he has no musculoskeletal symptoms.  His general health is good and he takes no medications.
A general physical examination is within normal limits.  Nail examination is normal.  His knees are shown in the photograph below.

What would be the most appropriate initial therapy for this patient?

Accepted Answer

This patient has plaque psoriasis, the most common form of psoriasis. It is characterized by sharply demarcated, erythematous plaques with an overlying thick, silvery scale. These lesions are most often seen on extensor surfaces such as the elbows, knees, hands, feet, and trunk. Psoriasis is usually graded as mild (affecting < 3% of the body), moderate (affecting 3%-10% of the body), or severe (affecting > 10% of the body). Treatment modalities are chosen based on the severity of disease, sites of involvement, relevant comorbidities, patient preference, efficacy, and patient response. Those with mild-to-moderate plaque psoriasis (as in this patient) should be treated initially with topical corticosteroids and emollients. Alternate therapies include tar, topical retinoids (eg, tazarotene), and topical vitamin D (eg, calcipotriene, calcitriol). Although topical vitamin D analogues are effective as monotherapy, combination therapy with topical corticosteroids is more effective than either therapy alone. For facial or intertriginous involvement, topical tacrolimus (Choice E) or pimecrolimus may be used as a corticosteroid-sparing agent as chronic corticosteroid use in these areas can cause harmful skin effects such as atrophy, telangiectasia, and perioral dermatitis. In consultation with a dermatologist, patients with moderate-to-severe plaque psoriasis should be treated initially with phototherapy (Choice C). Patients with contraindications to phototherapy (eg, history of melanoma, extensive nonmelanoma skin cancer), who fail phototherapy, or who have moderate-to-severe disease and psoriatic arthritis should be treated with a systemic agent. Systemic therapy includes immunosuppressive or immunomodulatory drugs such as methotrexate, cyclosporine, and biologic agents (eg, etanercept) (Choices A and B). Educational objective: Patients with mild-to-moderate plaque psoriasis should be treated initially with topical corticosteroids and emollients. Combination therapy with topical corticosteroids and vitamin D is more effective than either therapy alone. For facial or intertriginous involvement, topical tacrolimus or pimecrolimus may be used as corticosteroid-sparing agents. Phototherapy and systemic therapies (eg, methotrexate, biologic agents) should be used for moderate-to-severe disease in consultation with a dermatologist. __________ References: Current and future management of psoriasis. (http://www.ncbi.nlm.nih.gov/pubmed/17658398) Topical treatments for chronic plaque psoriasis. (http://www.ncbi.nlm.nih.gov/pubmed/19370616)

Question 8

A 57-year-old man comes to the physician for evaluation of a rash on his elbows and knees.  He initially had the rash 3 years ago, and it reoccurs every 3-4 months in the same regions.  The patient has no pruritus or discharge during the episodes but notices an occasional silvery scale.
Vital signs are within normal limits.  Skin examination of the left elbow is shown below.  There is no drainage from the lesions or tenderness to palpation.

Which of the following is the best next step in management of this patient?

Accepted Answer

11ec193a_978c_d6f7_853d_73da92447e9c_MD0002_00 This patient's presentation is consistent with plaque psoriasis, the most common form of psoriasis in adults. Patients develop symmetrical, erythematous plaques involving the scalp, knees, back, and extensor surfaces of the elbows, with a raised border and often a light or silvery scale. Less commonly affected areas include the external ear canal, intertriginous areas, and nail plates (pitting). Most patients are otherwise asymptomatic, but some may develop pruritus. Topical glucocorticoids are the mainstay of therapy for localized mild to moderate plaque psoriasis (<5% of body surface area). High-potency agents (eg, betamethasone, clobetasol) should be used initially to treat thick plaques on extensor surfaces; these are given as a twice-daily application for up to 4 weeks. Longer treatment is an option, but it should be closely monitored and lower-potency agents should be considered. Alternate therapy includes topical vitamin D analogs (eg, calcipotriene) or topical retinoids. Moderate to severe disease (5%-10% of body surface area or disabling lesions of face, palm, or sole) usually requires systemic therapy (methotrexate, biologic immunomodulators such as etanercept) or phototherapy (Choice A). (Choices C and E) Low-potency topical steroids are indicated for facial and intertriginous plaque psoriasis as high-potency topical steroids can cause corticosteroid-induced skin atrophy in these areas. Topical calcineurin inhibitors (eg, tacrolimus) are also an alternate treatment for facial and intertriginous involvement. (Choice D) Oral corticosteroids are usually avoided for treating plaque psoriasis due to increased adverse effects compared to other systemic treatments. In addition, withdrawal of systemic steroids may lead to an abrupt flare of psoriasis. Educational objective: Mild to moderate plaque psoriasis is treated with high-potency topical steroids and emollients. Moderate to severe disease (involvement of 5%-10% of body surface area or disabling lesions of face, palm, or sole) usually requires systemic therapy (methotrexate, biologic immunomodulator such as etanercept) or phototherapy. __________ References: Topical therapies for the treatment of plaque psoriasis: systematic review and network meta-analyses. (http://www.ncbi.nlm.nih.gov/pubmed/23413913) Topical therapies for the treatment of plaque psoriasis. (http://www.ncbi.nlm.nih.gov/pubmed/19916297)

Question 9

A 45-year-old man comes to the physician for evaluation of a rash on his right leg.  He initially developed a minor traumatic laceration 3 weeks ago.  He applied hydrogen peroxide and an over-the-counter topical antibiotic cream (neomycin-polymyxin-bacitracin).  The laceration improved during the first 4 days, but then a rash with significant pruritus and clear drainage developed around the wound over the next 2 weeks.  The patient has a history of diabetes, hypertension, and hypercholesterolemia.  His current medications include metformin, lisinopril, and rosuvastatin.  He has no history of tobacco or alcohol use.
His vital signs are within normal limits.  Skin examination of the right leg is shown below.  There is clear drainage from the lesions and warmth to palpation.  There is no tenderness.  Examination of the extremities shows no pedal or ankle edema.  The remainder of his physical examination is normal.

Which of the following is the most likely diagnosis?

Accepted Answer

This patient's presentation is consistent with allergic contact dermatitis (ACD), most likely from topical antibiotic use. ACD is a delayed hypersensitivity response to an exogenous agent such as latex, soaps/cleaning agents, cosmetic products, or topical medications. Patients typically develop erythematous, indurated, and pruritic plaques around the contact site. Severe cases can present with edema, drainage, and vesiculation with bullae. Continued exposure to the offending agent can lead to dry, scaly skin. Diagnosis of ACD is usually made based on clinical findings, but some cases may require skin biopsy and/or patch testing for confirmation. ACD will often resolve promptly following discontinuation of the offending agent, though topical glucocorticoids may be useful for patients with significant discomfort. Patients should also be counseled that most minor cuts and scrapes do not require topical antibiotics as these would only increase ACD risk and contribute to antibiotic resistance. (Choice B) Erysipelas is a superficial skin infection involving the upper dermis and subcutaneous fat. Patients develop well-demarcated plaques with erythema, edema, and warmth. In addition, systemic symptoms (eg, fever, chills) are usually present, but significant pruritus is not seen. Erysipelas (Choice C) Necrotizing fasciitis is a deep skin infection with progressive destruction of the muscle fascia. Patients develop systemic signs (eg, fever, hypotension) with skin erythema, edema, warmth, and exquisite tenderness without significant pruritus. (Choice D) Stevens-Johnson syndrome is usually caused by systemic medications. It presents with a flu-like prodrome followed by mucocutaneous lesions. The lesions begin as erythematous macules that subsequently develop blistering, necrosis, and sloughing. Stevens-Johnson syndrome (Choice E) Toxic shock syndrome is characterized by rapid onset of severe systemic signs (eg, fever, hypotension) associated with a diffuse erythematous rash. Educational objective: Allergic contact dermatitis is frequently caused by latex, soaps/cleaning agents, cosmetic products, and topical medications. It is characterized by local erythema, pruritus, vesiculation, and swelling. __________ References: Contact dermatitis to topical medicaments: a retrospective chart review from the Ottawa Hospital Patch Test Clinic. (http://www.ncbi.nlm.nih.gov/pubmed/23010827) Allergic contact dermatitis to antibacterial agents. (http://www.ncbi.nlm.nih.gov/pubmed/19386217)

Question 10

A 32-year-old man comes for evaluation of a bump on the right side of his chest.  He initially noticed it 4 months ago, and it has grown slightly larger in the past month.  The patient has not experienced any trauma to the area or recent surgeries.  He does not use tobacco or alcohol.
Skin examination is shown below.  There is no drainage from the lesion or tenderness to palpation.  The lesion does not change in shape when pinched at the edges.  The remainder of his physical examination is within normal limits.

Which of the following is the most likely diagnosis?

Accepted Answer

This patient's lesion is consistent with an epidermal inclusion cyst (EIC, also known as epidermal cyst), which is a benign nodule containing normal epidermis that produces keratin. Although EIC often occurs when epidermis becomes lodged into the dermis due to trauma or comedones, many patients have no history of trauma or acne. EIC can occur anywhere on the body but is most common on the face, neck, scalp, and trunk. A lesion can remain stable or gradually increase in size. EICs may occasionally rupture, resulting in significant inflammation and involvement of surrounding tissue. Diagnosis is made clinically, with examination showing a dome-shaped, firm, and freely movable cyst or nodule with a central punctum (small, dilated, pore-like opening). Larger and more inflamed lesions can have a thick, yellowish-white, cheesy, and malodorous discharge. Lesions usually resolve spontaneously but can recur. Excision may be requested by patients for cosmetic reasons but is otherwise not needed. Incision and drainage are occasionally needed for infected and fluctuant cysts that are painful and erythematous. Gardner syndrome is characterized by colon cancer and numerous EICs involving the extremities. (Choice A) Acne vulgaris typically presents with comedones, which are impacted cells in the lumen of a sebaceous follicle. Open comedones (black heads) usually appear black with a wide open orifice and no central punctum. comedones (Choice B) Dermatofibroma is a benign fibroblast proliferation that typically appears as a firm, hyperpigmented nodule, most often on the lower extremities. It is nontender and has a fibrous component that may cause dimpling in the center when the area is pinched ("dimple" or "buttonhole" sign). Dermatofibroma (Choice D) Lipomas are benign, solitary, and painless subcutaneous nodules with a normal overlying epidermis. In contrast to epidermal cysts, lipomas are usually soft to rubbery and do not have a central punctum. Lipomas (Choice E) Pyogenic granuloma is a benign vascular tumor of the skin or mucus membranes that typically presents as a shiny red mass. The lesion can grow rapidly and has a friable surface that often bleeds with minor trauma. Pyogenic granuloma Educational objective: Epidermal inclusion cyst is a benign nodule containing normal epidermis that produces keratin. Patients usually develop a dome-shaped, firm, and freely movable cyst or nodule with a small central punctum. The lesion can remain stable or gradually increase in size but usually resolves spontaneously. __________ References: Epidermal inclusion cyst embedded in a recurrent benign fibrous histiocytoma. (http://www.ncbi.nlm.nih.gov/pubmed/25284857)

Question 11

A 22-year-old woman comes to the physician with several depigmented skin lesions on her hands and feet.  She has no other physical complaints.  Her past medical problems include migraine headaches, for which she takes naproxen as needed.  She is married and has an 8-month-old child.
Vital signs are within normal limits.  Skin examination findings are shown below.
Which of the following is the most appropriate next step in management of this patient?

Accepted Answer

Vitiligo is an acquired skin depigmentation (localized or generalized) likely due to a progressive autoimmune destruction of melanocytes. Patients usually present by age 20-30 with well-demarcated and depigmented lesions. Diagnosis is primarily clinical. Vitiligo is frequently associated with other autoimmune diseases (eg, autoimmune thyroid disease, type I diabetes). Studies indicate a higher incidence of autoimmune thyroid disease in vitiligo (up to 20% of patients) compared to non-vitiligo patients. The vitiligo usually precedes the onset of thyroid disease. As a result, most guidelines recommend screening vitiligo patients for autoimmune thyroid disease and type I diabetes. Treatment involves repigmentation with topical corticosteroids (preferred), topical calcineurin inhibitors, or ultraviolet light. (Choices A and B) All other autoimmune conditions (eg, pernicious anemia, systemic lupus erythematosus) are less common and require screening (eg, antinuclear antibodies, complete blood count) only in patients with suggestive symptoms, family history, or examination findings. (Choice C) Intralesional corticosteroid injections are the preferred treatment for alopecia areata, which typically presents with isolated patches of hair loss. Although it can be associated with vitiligo, alopecia areata does not directly cause loss of skin pigmentation. (Choice D) Skin biopsy is required only in atypical cases to differentiate vitiligo from other disorders. Educational objective: Vitiligo is an autoimmune skin disease causing partial or complete loss of melanocytes in affected skin. It presents as depigmented patches and is associated most frequently with thyroid disorders and type I diabetes. __________ References: Skin findings in thyroid diseases. (http://www.ncbi.nlm.nih.gov/pubmed/19327604) The prevalence of thyroid disease in patients with vitiligo: a systematic review. (http://www.ncbi.nlm.nih.gov/pubmed/22860695) Vitiligo: a comprehensive overview Part I. Introduction, epidemiology, quality of life, diagnosis, differential diagnosis, associations, histopathology, etiology, and work-up. (http://www.ncbi.nlm.nih.gov/pubmed/21839315) Epidemiology of vitiligo and associated autoimmune diseases in Caucasian probands and their families. (http://www.ncbi.nlm.nih.gov/pubmed/12753387)

Question 12

A 55-year-old woman comes to the physician with a 6-month history of a diffuse rash.  The patient has episodes of localized itching on her arms followed by a rash that worsens over a few hours before spontaneously resolving.  The rash has also occurred on her arms, legs, and back.  The most recent episode occurred 2 days ago, and the patient has brought a photograph of the rash, shown below.  She has no trauma, insect bites, travel history, or sick contacts.  The patient has a history of hypertension, diabetes, and osteoarthritis of her knees.  Her medications include metformin, lisinopril, and occasional ibuprofen.  She does not use tobacco, alcohol, or illicit drugs.
The patient's temperature is 36.1 C (97 F), blood pressure is 138/77 mm Hg, and pulse is 78/min.  Her physical examination is within normal limits.

Which of the following is the next best step in management of this patient?

Accepted Answer

11ec193a_9789_7b91_853d_39437d096c82_MD0002_00 This patient's clinical features are consistent with chronic urticaria, defined as episodic symptoms lasting >6 weeks. Urticaria is due to mast cell activation in the superficial dermis, with release of multiple mediators (eg, histamine) that cause pruritus and localized swelling in the upper layers of the skin. It can also be associated with angioedema due to mast cell activation in the deeper dermal and subcutaneous tissues. Chronic urticaria can be due to physical stimuli (eg, cold temperature, skin pressure), serum sickness, or systemic disorders (eg, autoimmune disease, vasculitis, malignancy). However, for many patients, the cause is not known (idiopathic urticaria). Chronic urticaria is usually treated in a stepwise approach, initially with a second-generation (nonsedating) antihistamine (eg, loratadine). If needed, the dose may be increased to 2-4 times the standard dose. Second-line therapies in patients who do not respond include a first-generation antihistamine, a leukotriene receptor antagonist, and an H₂ blocker. Patients with persistent symptoms may require subspecialist referral for immunosuppressive therapies (eg, hydroxychloroquine, tacrolimus, omalizumab). (Choice A) First-generation antihistamines, such as diphenhydramine or hydroxyzine, are associated with significant sedation. They can be added at bedtime in patients who do not respond to nonsedating antihistamines alone. (Choices C and E) Leukotriene receptor antagonists and H2 blockers are useful add-on therapies in patients who do not respond to initial therapy. They are only marginally effective in monotherapy for initial treatment. (Choice D) Oral glucocorticoids may be used in brief courses in patients who fail initial therapy. But they are associated with significant adverse effects when used for extended periods. Educational objective: Initial treatment of chronic urticaria includes second-generation antihistamines (eg, loratadine). Treatment for refractory patients includes first-generation antihistamines, leukotriene receptor antagonists, H₂ blockers, or a brief course of oral steroids. __________ References: EAACI/GA(2)LEN/EDF/WAO guideline: management of urticaria. (http://www.ncbi.nlm.nih.gov/pubmed/19772513)

Question 13

A 35-year-old woman comes to the physician for evaluation of a rash on her hands.  She noted the onset of periungual swelling around all her fingers 2 weeks ago.  She subsequently developed a rash with stinging pain and burning on some of her fingertips.  The patient has worked as a manicurist for the past 10 years and has worn artificial nails intermittently for the past 2 years.  She has a history of hypothyroidism and gastroesophageal reflux disease.  Her medications include omeprazole and levothyroxine.  She has no history of tobacco or alcohol use.
Vital signs are within normal limits.  Skin examination of the fingers reveals mild warmth, edema, and tenderness to palpation.  There are also fissures at the distal fingers.  Neurological examination shows decreased sensation at the patient's fingertips.  The remainder of her physical examination is normal.
Which of the following is the most likely diagnosis?

Accepted Answer

This patient's presentation is consistent with allergic contact dermatitis (ACD), most likely due to artificial nails. ACD is a delayed hypersensitivity response to exogenous agents such as latex, nickel, soaps/cleaning agents, cosmetic products, rubber, and formaldehyde. Artificial nails often contain formaldehyde and acrylates. ACD to artificial nails can occur in both manicurists applying the nails and customers receiving them. Clinical findings can include periungual edema or eczema, nail dystrophy, periungual hyperkeratosis, fingertip dermatitis, and paresthesias. Diagnosis is usually based on clinical findings, but some cases may require skin biopsy and/or patch testing for confirmation. Symptoms usually improve with removal of the artificial nails. (Choice A) Acute paronychia is a bacterial infection (most commonly Staphylococcus aureus) of the nail fold and surrounding tissues. Clinical findings include swollen and tender nail folds (posterior or lateral), often with a purulent fluid collection. Paronychia would not cause symmetric involvement of multiple nails. Acute paronychia (Choice C) Distal subungual onychomycosis typically presents with nail discoloration (white, yellow, or brown), thickening, and deformity. However, it is not usually associated with paresthesias or fissures as seen in this patient. (Choice D) Herpetic whitlow is due to inoculation of the herpes virus into broken skin. Patients typically develop tingling and burning of the hand associated with a vesicular rash. The absence of the typical vesicular rash in this patient makes herpetic whitlow unlikely. Herpetic whitlow (Choice E) Psoriasis of the nail can present with nail plate pitting, nail bed salmon patches, and onycholysis (distal separation of the nail plate from the inflamed underlying nail bed). Psoriasis of the nail Educational objective: Allergic contact dermatitis is a delayed hypersensitivity response to an exogenous agent. Clinical findings in contact dermatitis due to artificial nails can include periungual edema or eczema, nail dystrophy, periungual hyperkeratosis, fingertip dermatitis, and paresthesias. __________ References: Allergic contact dermatitis from acrylates in artificial nails. (http://www.ncbi.nlm.nih.gov/pubmed/15573650) Contact and primary irritant dermatitis of the nail unit diagnosis and treatment. (http://www.ncbi.nlm.nih.gov/pubmed/17403259)

Question 14

A 36-year-old man comes to the office due to a leg injury.  He suffered an abrasion to his right leg after falling from his motorcycle 5 days earlier.  The patient washed the wound with tap water and covered it with an occlusive dressing but is now having increasing pain.  He has not removed the dressing for the last 3 days due to pain.  Past medical history is unremarkable.  On examination, he is afebrile but has a 10-cm abrasion on the lateral right leg involving the epidermis and superficial dermis.  There is a surrounding area of erythema and warmth extending 3-5 cm from the margin of the wound.
Which of the following is the most appropriate next step in management of this patient?

Accepted Answer

This patient has a large abrasion with signs of associated moderate cellulitis. In addition to erythema and purulence, clinical features suggesting infection include increasing pain, swelling, fever, lymphangitis, and regional adenopathy. Mild superficial infections (eg, impetigo) in immunocompetent patients may be treated with topical mupirocin (Choice D). However, more extensive cellulitis (>2 cm from the wound margin) or infection of deep tissues should be treated with systemic antibiotics. impetigo deep tissues Patients with moderate cellulitis may be managed with oral antibiotics that have good coverage for Staphylococcus and Streptococcus species. Cellulitis without pustules or purulent exudate may be treated with clindamycin, dicloxacillin, or cephalexin. However, purulence suggests infection with methicillin-resistant S aureus, and antibiotics other than cephalosporins are recommended. First-choice antibiotics include clindamycin or trimethoprim/sulfamethoxazole. Moderate infection associated with bite wounds should receive antibiotics with anaerobic coverage (eg, amoxicillin/clavulanate). Immunocompromised patients or those with severe wound infections (eg, high fever, hemodynamic instability) will require hospitalization for intravenous antibiotics (Choice A). cellulitis bite wounds (Choice C) Hydrogen peroxide may be considered in initial wound management to remove dried blood and necrotic debris, but it is ineffective in treating established wound infections and does not promote healing. (Choice E) Wet-to-dry and wet-to-moist gauze dressings are frequently used to aid debridement in wounds with extensive exudate. However, gauze dressings are labor-intensive and do not reliably maintain a moist wound environment. Educational objective: Mild superficial wound infections in immunocompetent patients may be treated with topical mupirocin. More extensive cellulitis (>2 cm from the wound margin) or infection of deep tissues should be treated with systemic antibiotics. __________ References: Common questions about wound care. (http://www.ncbi.nlm.nih.gov/pubmed/25591209)

Question 15

A 45-year-old woman comes to the physician with "reddish spots" on her legs. She first noticed them 3 months ago and says that they are slowly spreading. Her medical problems include type 2 diabetes mellitus, acid reflux disease, hypertension, chronic constipation, and hypothyroidism. Her medications include metformin, levothyroxine, lisinopril, omeprazole, and as-needed senna. Her temperature is 37.2 C (99 F), blood pressure is 120/80 mm Hg, pulse is 78/min, and respirations are 12/min. Her body mass index is 27 kg/m². Several spots are seen in the pretibial region of each leg, as shown in the image below. The examination also shows clear lung fields, normal first and second heart sounds, and a 1/6 systolic murmur at the apex. Which of the following is the most likely diagnosis?

Accepted Answer

Necrobiosis lipoidica diabeticorum (NLD) is a skin condition frequently seen in diabetics, although it is occasionally seen in nondiabetics as well. Because the skin lesions may precede the onset of diabetes, patients with NLD should be screened for diabetes. The lesions typically occur in the pretibial areas, starting as erythematous papules that later evolve into annular lesions with a yellowish-brown hue, dilated blood vessels, and central epidermal atrophy. Patients are usually asymptomatic but can develop pain, pruritus, or dysesthesia. Histological examination showing characteristic interstitial granulomatous dermatitis confirms the diagnosis. NLD lesions may occasionally ulcerate. In the absence of ulceration, treatment with high-potency topical or intralesional glucocorticoids can be attempted. (Choice A) Discoid lupus lesions are usually erythematous, scaly plaques with pigmentary changes, such as hyperpigmented rims, that are commonly seen on the face, scalp, and ears. They may also be present on the trunk and extremities. However, it is uncommon to find discoid lesions below the neck without lesions also being present above the neck. Discoid lupus (Choice B) Hypersensitivity reactions to drugs may manifest with a variety of skin lesions, including urticaria, morbilliform rash, erythroderma, or vasculitis/palpable purpura. Isolated, chronic, annular lesions would be uncommon. morbilliform rash vasculitis/palpable purpura (Choice D) Pretibial myxedema (thyroid dermopathy) presents as nonpitting edema and skin-colored or brawny, indurated plaques in the pretibial areas. It is almost always associated with other features of Graves' disease, especially ophthalmopathy. Pretibial myxedema (thyroid dermopathy) (Choice E) The most common skin manifestations of sarcoidosis are papules and plaques occurring in the face and neck, typically over the nose, nasolabial folds, and eyelids. The papules may be skin-colored, brownish, or hypopigmented. Patients with Lofgren syndrome (acute sarcoidosis and polyarthralgia) can have tender, erythematous, subcutaneous nodules in the anterior shin (erythema nodosum), usually associated with adenopathy and joint symptoms. erythema nodosum Educational objective: Necrobiosis lipoidica diabeticorum is a skin condition seen frequently in patients with diabetes. The lesions typically occur in the pretibial areas and manifest as annular lesions with a yellowish-brown hue, dilated blood vessels, and central epidermal atrophy. __________ References: Update on necrobiosis lipoidica: A review of etiology, diagnosis, and treatment options. (http://www.ncbi.nlm.nih.gov/pubmed/23969033) Dermatologic manifestation of diabetes. (http://www.ncbi.nlm.nih.gov/pubmed/21848812) Diagnosis of cutaneous sarcoidosis; clinical and the prognostic significance of skin lesions. (http://www.ncbi.nlm.nih.gov/pubmed/23521826)

Question 16

A 45-year-old obese woman with diet-controlled diabetes mellitus comes to the physician with mild pruritus in both axillary areas.  Physical examination findings are shown in the image below.

Examination with Wood's lamp shows red fluorescence in the affected areas.  Which of the following is the most likely diagnosis?

Accepted Answer

Erythrasma presents with well-demarcated, pruritic, red-brown plaques, most commonly in interdigital (especially the toes) and intertriginous areas. It can occasionally have a fine "cigarette paper" scale. It is a superficial skin infection caused by Corynebacterium minutissimum and can be seen in healthy patients, although those with impaired immune systems (eg, diabetes) are at increased risk. C minutissimum, which is part of normal skin flora, can overgrow and cause disease under conditions of moisture and occlusion. The diagnosis of erythrasma is based on its appearance on examination, but can be confirmed by examining the affected areas under a Wood's lamp and observing its classic coral-red appearance. The red color is due to the production of porphyrins by the bacteria, though they may be washed away by bathing producing a false-negative result. Limited disease is treated with topical antibiotics (clindamycin 1%). Topical antifungals (miconazole) can also be used for limited disease as they can be effective for erythrasma and coexisting dermatophyte infection. Systemic therapy with oral macrolides (erythromycin or clarithromycin) is reserved for more extensive disease (multisite disease). (Choice A) Candidal intertrigo is a common pruritic, intertriginous infection. It has risk factors similar to erythrasma, and also occurs in areas of moist, occluded skin. Typical lesions are erythematous, macerated plaques with peripheral scaling. Candidal intertrigo is diagnosed by examining skin scrapings in potassium hydroxide (KOH) showing budding yeast with septate hyphae. It does not have a red appearance under a Wood's lamp. Candidal intertrigo (Choice C) The plaques of inverse psoriasis are present in intertriginous areas such as the axillae and inframammary areas, as opposed to typical plaque psoriasis which appears on the extensor surfaces of extremities, scalp, and back. The plaques are also erythematous and well-demarcated but may not have the typical psoriatic scale and are frequently not pruritic. The lesions do not exhibit any fluorescence under Wood's lamp examination. inverse psoriasis (Choice D) Microsporum is one of the 3 most common causative agents of tinea infections. Tinea infections also affect otherwise healthy individuals, but patients with some level of immunosuppression are at increased risk. The typical lesion is an erythematous, ring-shaped, well-demarcated plaque and can be associated with pruritus. Diagnosis is made by demonstrating septate hyphae on potassium hydroxide (KOH) skin scrapings. One form of tinea capitis can give silver-blue fluorescence on Wood's lamp examination, but none are associated with the red glow of erythrasma. tinea infections (Choice E) Seborrheic dermatitis is a chronic, recurring, and usually very mild form of dermatitis that has an unknown etiology (although Malassezia has been indirectly implicated). More severe disease presents with erythematous plaques with yellow scale and occasional pruritus. Seborrheic dermatitis is most commonly seen on the scalp, face, trunk, and intertriginous areas and is diagnosed clinically. It has no characteristic finding under a Wood's lamp. Seborrheic dermatitis Educational objective: Erythrasma is a superficial skin infection caused by Corynebacterium minutissimum. The lesions are well-demarcated, red-brown, pruritic, and most common in moist interdigital or intertriginous areas. Diagnosis is clinical and can be confirmed by the lesions' red fluorescence under a Wood's lamp. Limited infection is treated with topical antibiotics, while multisite disease may require oral macrolides. __________ References: Images in clinical medicine. A brilliant case of erythrasma. (http://www.ncbi.nlm.nih.gov/pubmed/15483285)

Question 17

A 65-year-old woman comes to the physician with a pruritic rash.  This is the second year the rash has appeared, both times during the onset of winter.  She has intensely pruritic areas on her lower extremities along the shins and above the right lateral malleolus.  The patient sometimes experiences pruritus on her lower back and the extensor surfaces of the forearms.  One area usually predominates.  There is no visible rash initially, but the involved areas can become rough and scaly after a few weeks of frequent scratching.  Her only other medical problem is perennial rhinitis.  Her medications include cetirizine, calcium plus vitamin D supplements, and a multivitamin.
Skin examination findings are shown in the photograph.

Which of the following is the best next step in management of this patient?

Accepted Answer

This patient's presentation of dry, scaly, itchy, and red skin is consistent with skin dryness (xerosis). Xerosis ('winter itch') is more common in the winter months due to dry weather. The elderly (who have decreased sebaceous/sweat gland activity) and patients who bathe frequently or take offending medications (eg, doxycycline) are at particularly high risk. The dry skin can easily become irritated, leading to pruritus and excoriations. One or a few areas are usually involved and systemic pruritus is not present. Patients eventually develop thickened and scaly lichenified plaques in pruritic areas. Areas not within reach of the hands are typically not involved. Most cases can be managed with daily skin moisturizers and topical emollients. Patients should also use gentle cleansers (eg, moisturizing bar soaps) and lukewarm (rather than hot) water when bathing. Other alleviating treatments include lotions (eg, calamine, menthol-containing) for cool skin relief, reducing possible skin irritants, using a humidifier in the winter, and stress reduction. More advanced cases may require topical corticosteroids. (Choice A) Capsaicin is derived from chili peppers and can be effective for neuropathic (eg, notalgia paresthetica, brachioradial pruritus) and certain pruritic conditions (eg, prurigo nodularis, aquagenic pruritus, pruritus associated with chronic renal disease). However, it is not as effective for xerosis. (Choice B) Generalized pruritus due to systemic causes requires further investigation, including thyroid-stimulating hormone, creatinine, bilirubin, calcium, and blood glucose levels. However, this patient's seasonal symptoms and localized pruritus make this less likely. (Choice D) Xerosis is usually a clinical diagnosis and requires a skin biopsy only in cases with unclear etiology. (Choice E) Topical terbinafine is effective for tinea corporis, a fungal infection that usually presents with ringlike papulosquamous eruptions on the arms and legs. tinea corporis Educational objective: Xerosis is dry skin due to depleted moisture that results in intensely pruritic areas. Recurrent excoriation of the area can expand the lesion and lead to lichenification. Most cases can be managed with daily skin moisturizers and topical emollients. __________ References: Dry skin in the elderly: complexities of a common problem. (http://www.ncbi.nlm.nih.gov/pubmed/21146730) Skin xerosis. Clinical report on the effect of a moisturizing soap bar. (http://www.ncbi.nlm.nih.gov/pubmed/348407)

Question 18

A 50-year-old man comes to the physician for evaluation of an itchy rash on his extremities for the last several weeks.  He was diagnosed with hepatitis C infection 6 months ago but refused further workup and treatment.  His vital signs are normal.  Skin findings are shown in the image below.  The remainder of the examination is within normal limits.

Which of the following is the most appropriate treatment for this patient's current condition?

Accepted Answer

This patient's skin findings are consistent with cutaneous lichen planus (LP), an immunologically mediated skin disorder affecting mainly middle-aged adults. Although the etiology is unknown, cutaneous LP has been associated in some cases with hepatitis C. A clinically similar lichenoid eruption can also occur with exposure to certain medications (eg, angiotensin-converting enzyme inhibitors, beta blockers). Patients typically develop a papulosquamous rash that can involve the skin, nails, mucous membranes of the mouth, and external genitalia. The classic skin lesions are characterized by the 4 Ps (pruritic, purple, polygonal shape, and papules/plaques) and most commonly occur on the flexural surfaces of the ankles and wrists. Lesions may also show lacy white markings known as Wickham's stria. Wickham's stria The diagnosis of LP is mainly clinical, based on the appearance and distribution of lesions. Uncertain cases may require punch biopsy for confirmation. Topical high-potency corticosteroids are preferred as first-line treatment for cutaneous LP. Patients who do not respond to topical therapy may require oral corticosteroids or phototherapy. (Choices A and E) Emollients and topical vitamin D are adjunctive therapies for psoriasis, which causes symmetrically distributed plaques involving the scalp, elbows, knees, and back. The plaques are usually erythematous with sharply defined borders and silvery scale. psoriasis (Choice B) Oral lamivudine is an antiviral medication indicated for treatment of HIV and hepatitis B. It is not used for hepatitis C and is not useful for LP. (Choice C) Topical antifungals can treat tinea corporis, which usually presents as an erythematous, pruritic, oval-shaped patch or plaque. The rash usually spreads centrifugally, which is not consistent with this patient's skin findings. tinea corporis Educational objective: Lichen planus causes pruritic, purple, polygonal papules or plaques involving the ankles and wrists, nails, oral mucous membranes, or external genitalia. It has been associated with hepatitis C. Topical corticosteroids are first-line treatment. __________ References: Lichen planus: an update and review. (http://www.ncbi.nlm.nih.gov/pubmed/22908728) Diagnosis and treatment of lichen planus. (http://www.ncbi.nlm.nih.gov/pubmed/21766756)

Question 19

A 30-year-old man comes to the physician for evaluation of a rash on his right thumb.  He initially noticed a small lesion near the nail margin that has progressively worsened over the past 2-3 weeks.  He has no other medical conditions and no history of tobacco or alcohol use.  He works in the kitchen of a local restaurant.  The patient has been sexually active with a single partner in the past year.
His temperature is 36.1 C (97 F), blood pressure is 128/76 mm Hg, and pulse is 78/min.  Skin examination findings are shown below.  The remainder of the physical examination is within normal limits.

Which of the following is the next best step in management of this patient?

Accepted Answer

This patient's skin lesion is consistent with warts (cutaneous verrucae), which are the most common cutaneous manifestation of human papillomavirus (HPV) infection. The virus usually enters through tiny cuts or skin abrasions after contact with an HPV-infected individual and can cause warts in various locations including plantar, periungual, palmar, or genital areas. Periungual warts are most common in individuals who bite their nails or have occupations causing chronically wet hands (eg, dishwashers). Periungual warts begin weeks to months after viral exposure and are characterized by thick cauliflower-like skin around the nail plate. There can be loss of the cuticle, paronychia, and pain from nail separation. Diagnosis is made clinically by skin examination. Although warts in other areas can spontaneously regress, periungual warts often persist and require treatment. Topical salicylic acid is the preferred treatment in most patients and is given for 2-3 weeks until the dead wart tissue sloughs off. Treatment is continued for another 1-2 weeks to prevent recurrence and eliminate residual virus. paronychia (Choice A) Curettage and desiccation can effectively remove the wart but is usually reserved for patients who fail topical therapy. The procedure involves numbing the skin with an anesthetic (eg, lidocaine) prior to scraping the wart off. (Choice B) Imiquimod is a topical immunomodulator that likely induces local cytokine production against the virus. However, it is usually reserved for patients who fail initial topical therapy. (Choice C) Liquid nitrogen cryotherapy is a second-line treatment option for patients who fail treatment with salicylic acid. However, cryotherapy in the fingers, which have dense innervation, can cause severe pain and residual neuropathy. It can also injure the nail bed leading to dystrophic nails. (Choice E) Shave or snip excision is typically used for filiform warts and is less effective for periungual warts. Patients are typically given topical lidocaine before using scissors (snip) or a scalpel (shave) to remove the wart. filiform warts Educational objective: Periungual warts are characterized by thick cauliflower-like skin around the nail plate and can lead to loss of the cuticle, paronychia, and pain. They usually do not regress spontaneously. Topical salicylic acid is the preferred treatment for most patients. __________ References: Topical treatments for cutaneous warts. (http://www.ncbi.nlm.nih.gov/pubmed/22972052)

Question 20

A 65-year-old man comes to the clinic with 1 week of pruritic facial rash.  He was recently diagnosed with community-acquired pneumonia and is on day 8 of his 10-day antibiotic course.  He otherwise feels healthy and has no other complaints.
His past medical history includes Parkinson disease, mild dementia, and hypertension.  His medications include carbidopa-levodopa, donepezil, amlodipine, and levofloxacin.
The rash is shown in the image below.

Which of the following is the best next step in management of this patient's facial rash?

Accepted Answer

This patient's presentation is most consistent with seborrheic dermatitis (SD). SD commonly affects areas with a high content of sebaceous glands such as the scalp (dandruff), face (nasolabial folds, eyebrows, and external ear), chest, and intertriginous areas. The etiology is unclear but is thought to be due to the growth of lipid-dependent Malassezia fungus. It occurs in all age groups but is seen with increased frequency in patients with Parkinson disease and HIV. Patients typically present with pruritic, erythematous plaques with fine, loose, yellow, and greasy scales. Symptoms may worsen during stressful periods or winter months. Treatment consists of topical corticosteroids to control inflammation and itching, antifungal creams or shampoos, or a combination of these. High-potency steroid creams are typically not used on the face due to the potential for discoloration, skin atrophy, and telangiectasias. The least potent steroid necessary should thus be used to minimize adverse effects (Choice B). SD is a chronic condition that usually recurs despite adequate treatment and requires repeated or long-term maintenance treatment. (Choice A) Drug rashes are maculopapular and typically occur in dependent areas with subsequent generalization. They are not usually localized to areas of the body rich in sebaceous glands. Drug rashes (Choice D) The diagnosis of seborrheic dermatitis is usually made by physical examination alone and does not require skin biopsy. However, biopsy is performed on rare occasions to exclude other conditions. (Choice E) Triple antibiotic cream is normally used to treat a bacterial infection. This patient's scaly-appearing rash and its distribution are less consistent with bacterial infection. Educational objective: Seborrheic dermatitis typically presents as erythematous plaques with fine, loose, yellow, greasy scales on areas of body rich in sebaceous glands. All age groups are affected, but it is seen with increased frequency in patients with Parkinson disease and HIV. Treatment consists of low-potency corticosteroids, antifungal creams, or a combination of these. __________ References: Optimizing treatment approaches in seborrheic dermatitis. (http://www.ncbi.nlm.nih.gov/pubmed/23441240)

Exam 3: Office/Health Center