Infeção Cutânea E Pulmonar Por Mycobacterium Africanum

Abstract

A tuberculose cutânea é uma doença incomum, constituindo 1,5% de todas as formas de tuberculose. Na doença pulmonar e cutânea, as infeções causadas por Mycobacterium africanum e Mycobacterium tuberculosis podem ser clinicamente indistinguíveis. Um rapaz de 6 anos da Guiné-Bissau foi hospitalizado devido a uma úlcera pré-auricular direita com evolução de dois anos e linfadenopatia regional. O teste tuberculínico foi positivo e a radiografia de tórax revelou um nódulo hipotransparente no lobo pulmonar direito, com características sólidas na TAC. As biópsias da úlcera e da linfadenopatia revelaram infiltrado linfocítico com reação granulomatosa; o exame cultural e a PCR confirmaram infeção por Mycobacterium africanum. Foi realizado tratamento antibacilar durante 6 meses, com redução significativa da lesão. Nos países desenvolvidos é importante relembrar as várias formas de tuberculose cutânea, que se pode apresentar isoladamente ou em associação com outras formas de infeção. Nos doentes provenientes de áreas endémicas, um teste tuberculínico positivo deve levantar a suspeita desta entidade. PALAVRAS-CHAVE – Tuberculose cutânea; Tuberculose pulmonar; Mycobacterium africanum; Criança.

Lupus Vulgaris: A Diagnostic Challenge

“…Although these tests are the gold standard for the diagnosis, they have a low sensitivity: 50% a 72% for PCR and 80% for culture in samples with BAAR negatives. 6 In the absence of such examination, a therapeutic test can be used, as corroborated by Pinho A et al and Thomas S et al 10,14,15 In this patient after a two months treatment with rifampicin, isoniazid, pyrazinamide and etambutol followed by four months of rifampicin and isoniazid there was a complete regression of the lesion (Fig. 4).…”

“…3,4 In general, cutaneous tuberculosis may have no systemic symptoms and the skin lesion is not specific, which can make the diagnosis a great challenge for dermatologists in daily practice. 6,12 Lesional characteristics in this patient associated with the high level of immunity precluded an early diagnosis. At this stage lupus vulgaris may mimic other dermatoses such as sporotrichosis, cutaneous leishmaniasis, discoid lupus erythematosus, sarcoidosis, acne rosacea, nummular dermatitis, psoriasis, lichen simplex chronicus, dermatophytosis and erythema annulare centrifugum.…”

“…13 The diagnosis is based on clinic and histopathological findings, bacterial cultures and PCR. 6 As lupus tuberculosis tends to occur in previously sensitized patients, PPD is usually positive, as in this patient, but its diagnostic value is considered controversial. Culture of the collected material may or may not show Koch's bacillus.…”

“…Current data from the literature indicate that cutaneous tuberculosis accounts for 1%-2% of all extrapulmonary forms of tuberculosis in the world, therefore a rare condition, especially in industrialized countries. 1,6 In Europe, the predominant form of cutaneous tuberculosis is lupus vulgaris, which may represent 61.1% of the cases, 7 whereas scrofuloderma is the most common presentation in some developing countries such as Brazil. 5 According to the WHO, Brazil is one of the twenty countries in the ranking with the highest incidence of tuberculosis, 8 and 40% of patients over 45 years of age with typical cutaneous lesions may have coexistent pulmonary tuberculosis, 9 which was not apparently the case of this patient.…”