A 34-year-old man presented with a large cutaneous lesion on his left thigh
that had started as a small papule when he was 13 years of age. The lesion
had enlarged slowly over the last 21 years. The patient had received bacil
lus Calmette-Guerin (BCG) vaccination in childhood. The family history was
significant for tuberculosis.
Clinical examination revealed a large, purplish-red, indurated plaque measu
ring 30 X 29 cm on the left thigh, extending to the buttock area. The edges
of the lesion had a serpiginous contour with an involuted center (Fig. 1).
A left inguinal lymph node was palpated.
Chest X-ray and blood cell count were normal. No other focus of disease was
identified. Laboratory testing for human immunodeficiency virus (HIV) infe
ction was negative. Purified protein derivative (PPD) intradermal injection
disclosed a 19-mm skin induration.
Both the cutaneous lesion and the inguinal lymph node were biopsied. Histop
athologic sections of the skin fragment showed epidermal hyperkeratosis, ne
ovascular proliferation, and a dense dermal lymphocytic infiltrate. The his
topathology of the lymph node demonstrated few granulomas with focal areas
of central necrosis.
Staining for fungus was negative. Ziehl-Neelsen staining was negative on bo
th the skin and lymph node specimens. Culture for fungus and Leishmania sp.
was negative. Tissue culture on Lowenstein-Jensen medium from skin and lym
ph node was positive for Mycobacterium colonies after 5 and 7 weeks, respec
tively.
Multidrug therapy was instituted with rifampin 600 mg/day, isoniazid 400 mg
/day, and pyrazinamide 2 g/day for 2 months, and then rifampin 600 mg/day a
nd isoniazid 400 mg/day alone for the next 4 months. An excellent response
was obtained at the end of treatment (Fig. 2).