Lupus vulgaris developing at the site of misdiagnosed scrofuloderma.
Cutaneous tuberculosis is a rare form of extrapulmonary tuberculosis primarily occurring in developing countries. The recent increase in the incidence of tuberculosis, especially due to human immunodeficiency virus (HIV) infections, has led to a resurgence of extrapulmonary forms of this disease. We describe a case of lupus vulgaris in a 33-year-old woman who had a 5-year history of a slowly growing plaque on her neck. The lesion was located at the site of surgery repairing the scar resulting from the incision of a subcutaneous abscess during childhood. This lesion was misdiagnosed as bacterial abscess. Histopathologic examination of the plaque revealed non-caseating tuberculoid granulomas consisting of lymphocytes, epithelioid and giant cells. Staining for acid-fast bacilli and culture from biopsied tissue was negative. Polymerase chain reaction (PCR) for detection of Mycobacterium tuberculosis DNA, performed on a skin biopsy specimen, was positive. A diagnosis of lupus vulgaris developing at the site of a previous misdiagnosed scrofuloderma was made. Conventional antitubercular therapy with rifampicin, isoniazid and ethambutol was administered for 6 months, resulting in resolution of the lesion.
Motta
A
A
Department of Dermatology, University 'G d'Annunzio', Via dei Vestini, 66100 Chieti, Italy.
Feliciani
C
C
Toto
P
P
De Benedetto
A
A
Morelli
F
F
Tulli
A
A
D000328:Adult; D000995:Antitubercular Agents / Q000627:therapeutic use; D004269:DNA, Bacterial / Q000235:genetics; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008177:Lupus Vulgaris / Q000175:diagnosis* / Q000188:drug therapy / Q000473:pathology; D009169:Mycobacterium tuberculosis / Q000235:genetics / Q000302:isolation & purification; D009333:Neck; D016133:Polymerase Chain Reaction; D014382:Tuberculosis, Cutaneous / Q000175:diagnosis
D000995:Antitubercular Agents; D004269:DNA, Bacterial