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?

Question

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?

Quizplus · 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)

A 49-Year-Old Woman Comes to the Physician for Evaluation of a Rash