Erythema induratum of Bazin and renal tuberculosis: report of an association Eritema indurado de Bazin e tuberculose renal: relato de uma associação

Abstract

Erythema induratum of Bazin is a disease that usually affects women, in whom erythematous subcutaneous nodules and plaques appear on the posterior part of the lower extremities, some of which ulcerate. In many countries, tuberculosis is still the main etiologic factor. We report a case of a 40-year-old woman who presented a course of protracted and recurrent episodes over five years of cutaneous lesions on her legs. These tend to involute, but new crops appear at irregular intervals. It was painful, erythematous-violaceous nodules, some of which drained a reddish secretion. The histopathologic features of the lesions demonstrated inflammatory infiltration, with predominance of neutrophils in dermis and hypodermis, necrotizing vasculitis in the arterioles and septal fibrosis. There was no granuloma. The Ziehl-Neelsen stain did not revealed acid-fast bacilli, and the culture of biopsy specimen was negative. The tuberculin skin test was strongly positive (17 mm). The chest X-ray was normal. Few months later she presented adynamia and urinary complaints, such as polacyuria and dysuria. It has been done an urynalysis, which demonstrated acid pH urine, sterile pyuria and microscopic hematuria. It was then raised the diagnostic hypothesis of renal tuberculosis. The urine culture for M. tuberculosis was positive in two out of ten samples. The treatment was instituted with rifampin, isoniazid and pyrazinamide, with complete regression. This case illustrates a clear association between erythema induratum and renal tuberculosis, demonstrated by the remission of the cutaneous lesions after the treatment of the renal tuberculosis.O eritema indurado de Bazin é doença caracterizada por erupções cutâneas que usualmente ocorrem nos membros inferiores de mulheres adolescentes e de meia idade. Relatamos o caso de paciente de 40 anos que apresentava há 5 anos lesões cutâneas em região inferior de ambas as pernas. Tratavam-se de nódulos eritemato-violáceos, dolorosos, alguns dos quais drenavam secreção serossangüínea. O exame histopatológico da biópsia de pele demonstrou infiltrado inflamatório, com predomínio de neutrófilos na derme e hipoderme, vasculite necrosante em arteríolas e fibrose septal. Não foram identificados granulomas. A coloração de Ziehl-Neelsen não revelou bacilos álcool-ácido resistentes, e a cultura do material biopsiado foi negativa. O PPD foi fortemente reator (17 mm). O raio-X de tórax era normal. Alguns meses depois, a paciente evoluiu com adinamia e sintomas urinários, como polaciúria e disúria. O exame de urina mostrou urina ácida, piúria estéril e hematúria. Foi levantada a hipótese de tuberculose renal. A urinocultura foi positiva para M. tuberculosis em duas amostras de dez solicitadas. O tratamento foi instituído com rifampicina, isoniazida e pirazinamida, com melhora considerável do quadro. Este caso ilustra uma associação clara entre o eritema indurado e a tuberculose renal, demonstrada através da remissão das lesões cutâneas após o tratamento da tuberculose renal.

Keywords

• Erythema induratum of Bazin
• Renal tuberculosis
• Cutaneous tuberculosis
• Vasculitis