Schistosoma mansoni Presenting as a Zosteriform Papular Eruption

A 27-year-old man was seen for a pruritic rash on the lower back that had been present for 2 days. He had been troubled by diffuse, intermittent pruritus requiring antihistamines for the previous 6 months. He had no other medical history. On examination, firm erythematous papules were present on the left side of the back in the distribution of the T8–T10 dermatomes (Figure 1A). There was no lymphadenopathy. A clinical diagnosis of herpes zoster was made, and 7 days of oral acyclovir (400 mg five times per day) were prescribed. Blood tests showed mild leukocytopenia without eosinophilia (3.7 × 103 cells/µL; reference range: 4.0–11.0 cells/µL) and elevated creatine kinase (460 IU/L; reference range: 40–320 IU/L). Total immunoglobulin E (IgE) was normal. Specific IgE testing was negative for a range of allergens.