Presenter: Adeline Kikam DO, Carlos A. Rivera MD
Dermatology Program: South Texas Dermatology Residency Program, Bay Area Corpus Christi Medical Center
Program Director: Rick Lin, DO MPH
Submitted on: Oct 18, 2018
CHIEF COMPLAINT: ¨Itchy lesion on right leg”
CLINICAL HISTORY:
Signs and symptoms: 36-year-old Hispanic male complaining of a lesion on the right lateral leg that began sometime around September of 2017. The patient recalls itching but no pain to the area followed by mild scaling. He does not recall any foreign travel around September of 2017 but he says he runs bushy trails around Houston, Dallas, and Austin. His last international travel was to Cancun Mexico in 2016. He denies any systemic symptoms such as fever, fatigue, and weight loss. All other review system questions and physical exam was unremarkable.
Previous Treatment: He self-treated with Neosporin and Hibiclens but it did not resolve.
PHYSICAL EXAM:
Solitary atrophic plaque to the right lateral leg with an erythematous center and greyish violaceous outer rim with fibrinoid material.
LABORATORY TESTS:
N/A
DERMATOHISTOPATHOLOGY:
The patient’s histopathology returned as the following:
On low power there was diffuse mixed granulomatous dermal infiltrate of lymphocytes, histiocytes, plasma cells, neutrophils, and multinucleated giant cells; occasional caseation necrosis.
On high magnification Amastigote organisms present within histiocytes and are visible with H&E stains, but are best seen with the Giemsa stain. Sometimes they marginate around the edge of clear space in the tissue like flashing lights around the edge of a sign (marquee sign).
DIFFERENTIAL DIAGNOSIS:
1. Bacterial infection
2. Pyoderma gangrenosum
3. Ecthyma
4. Cutaneous malignancy
5. Sarcoidosis
6. Lichen simplex chronicus
7. Cutaneous Leishmaniasis
8. Spider bite