A 20-year-old woman comes to the office due to headache, fatigue, malaise, myalgias, and fever. She has no known sick contacts. The patient recently returned from a summer internship as an arborist at a New Jersey nature preserve. She has a monogamous sexual relationship with her partner. Temperature is 37.9 C (100.2 F), blood pressure is 124/78 mm Hg, and pulse is 98/min. Oropharyngeal examination is normal, and no cervical lymphadenopathy is present. There is a 4-cm, flat, annular lesion on her right lower abdomen with no scaling, raised borders, induration, or purulence. Which of the following is the best next step in management of this patient?

Question

A 20-year-old woman comes to the office due to headache, fatigue, malaise, myalgias, and fever.  She has no known sick contacts.  The patient recently returned from a summer internship as an arborist at a New Jersey nature preserve.  She has a monogamous sexual relationship with her partner.  Temperature is 37.9 C (100.2 F), blood pressure is 124/78 mm Hg, and pulse is 98/min.  Oropharyngeal examination is normal, and no cervical lymphadenopathy is present.  There is a 4-cm, flat, annular lesion on her right lower abdomen with no scaling, raised borders, induration, or purulence.  Which of the following is the best next step in management of this patient?

Quizplus · Accepted Answer

11ec25c8_d132_3c44_bc81_03f90dc8b415_MD0003_00 This patient who worked outdoors in a Lyme-endemic area and developed systemic symptoms and an annular rash likely has early localized Lyme disease due to Borrelia burgdorferi, a spirochete transmitted by the Ixodes scapularis tick during blood feeding. Lyme-endemic area Symptoms of early localized Lyme disease develop 7-14 days after inoculation. The hallmark feature is erythema migrans (EM), a flat, annular macule at the tick bite site that slowly expands outward as the spirochete moves through the dermis. Areas of central clearing form over time, leading to the classic bull's-eye appearance. Systemic manifestations (eg, headache, myalgia, fever, malaise) also commonly occur. bull's-eye appearance Diagnosis is based on characteristic symptoms because B burgdorferi serology is generally negative at this early stage of illness (the humoral response is still being formed). Empiric treatment with a 14-day course of oral doxycycline is curative in most patients. (Choice A) Biopsy of a skin lesion is generally reserved for rashes that do not improve with standard therapy or when malignancy is suspected. This patient's systemic symptoms and flat, annular lesion with no scaling or raised borders is classic for Lyme disease. (Choice B) B burgdorferi serology is diagnostic for patients with early disseminated (eg, multiple EM lesions, cranial nerve paralysis, carditis) and late (eg, monoarticular arthritis) Lyme disease. However, it is not used for early localized Lyme disease because it is often falsely negative. (Choice C) Monospot testing is used for infectious mononucleosis, which is common in college-aged patients and often presents with systemic symptoms. However, most patients have a sore throat, pharyngitis, and lymphadenopathy; a diffuse (not focal) rash is occasionally seen. (Choice E) Tinea corporis is a common cause of an annular-shaped skin lesion on the trunk. However, it is generally scaly with raised borders and is not associated with systemic symptoms. (Choice F) Reassurance and symptomatic care are appropriate for most viral upper respiratory infections; most patients have rhinorrhea, nasal congestion, and/or cough. (Choice G) Although systemic lupus erythematosus is often associated with systemic symptoms and a diverse range of rashes, a single, flat, annular lesion with no scaling or raised borders is uncommon. Educational objective: Early localized Lyme disease should be suspected in individuals in Lyme-endemic areas who develop a flat, annular rash with or without central clearing. The diagnosis is made clinically because serology is negative in early disease; doxycycline is usually curative. References: Laboratory evaluation in the diagnosis of Lyme disease. (http://www.ncbi.nlm.nih.gov/pubmed/9412316) The clinical assessment, treatment, and prevention of Lyme disease, human granulocytic anaplasmosis, and babesiosis: clinical practice guidelines by the Infectious Diseases Society of America. (http://www.ncbi.nlm.nih.gov/pubmed/17029130)

A 20-Year-Old Woman Comes to the Office Due to Headache