HISTORY:
A 50+ year-old female presents for evaluation of a non-healing skin lesion on the left elbow present since a trip to Costa Rica a few months ago. It is itchy and the patient’s husband worries there is a bug inside her skin. The patient has been bandaging and using Neosporin. Exam shows an erythematous plaque and papule with ulceration. Initial clinical impression is spider bite. Patient was prescribed betamethasone 0.05% topical ointment BID for up to two weeks.
The lesion did not improve with betamethasone and an outside provider prescribed 10-day sulfa in the interim. At two weeks, follow up exam shows firm cord underneath skin, central ulceration and necrosis, and erythematous plaque. Betamethasone was discontinued and instead mupirocin 2% topical ointment TID was prescribed. At four weeks, two punch biopsies were performed for pathology.
QUESTION:
The new differential diagnosis was spot on, can you guess it?
Click to view enlarged photo.
ANSWER
Cutaneous Leishminiasis
PATHOLOGY
Histologic sections show a punch of skin to the deep reticular dermis with superficial and deep diffuse dermal granulomatous inflammatory reaction, including infiltrate of lymphocytes, histiocytes, plasma cells, and neutrophils. Occasional focal caseating necrosis is noted. Leishminiasis is noted within the histiocytes, confirmed by Giemsa stain. The inflammatory infiltrate extends to the subcutis. The overlying epidermis show spongiosis with hyperkeratosis.
CASE SUMMARY
Leishmaniasis is a protozoal infection transmitted through the bite of a sandfly. Presentations range from ulcerating nodules, visceral involvement, and oral-mucosal involvement. Leishmaniasis can be treated with pentavalent antimony for cutaneous lesions, and amphotericin B for visceral disease.
FOLLOW-UP
At 8 weeks from initial visit, the lesion continues to show ulceration with destruction to underlying cartilage (chiclero ulcer), visceral involvement, and erythematous nodule. The site was treated with liquid nitrogen and the patient is in contact with the tropical medicine infectious disease doctor in Costa Rica.
By: Dr. Ling Xia, MD; Dr. Saundra Seaman, MD; Jessica Joyce, PA-C