Cutaneous tuberculosis.

Cutaneous tuberculosis continues to be one of the most elusive and more difficult diagnoses to make for dermatologists practicing in developing countries. Not only because they have to consider a wider differential diagnosis (leishmaniasis, leprosy, actinomycosis, deep fungal infections, etc) but also because of the difficulty in obtaining a microbiological confirmation. Despite all the advances in microbiology, including sophisticated techniques such as polymerase chain reaction, the sensitivity of new methods are no better than the gold standard, that is, the isolation of Mycobacterium tuberculosum in culture. Even now, in the 21st century, we rely on methods as old as the intradermal reaction purified protein derivative (PPD) standard test and therapeutic trials, as diagnostic tools. In this situation, it is important to recognize the many clinical faces of cutaneous tuberculosis to prevent missed or delayed diagnoses.

[Clinical forms of the cutaneous tuberculosis]. / Formes cliniques de la tuberculose cutanée.

Since Laennec's description of the "prosector's wart" in 1826, science has made great strides forward. The cutaneous forms of the infection with Mycobacterium tuberculosis are various. The most common clinical forms of cutaneous tuberculosis are lupus vulgaris and scrofuloderma. The clinical forms of cutaneous tuberculosis are usually classified according to the patient's immune status, and the way through which the skin has been infected. Nonetheless, as in leprosy, a classification based on the importance of the bacterial inoculum in situ is possible. Subsequently the diagnosis should be considered as easy in the multibacillary forms and much more difficult in the paucibacillary forms. In the former, the diagnosis should rely on bacteriological data. In the latter, the diagnosis will rely on the association of epidemiological, clinical and histological data whereas genomic amplification with PCR may be of potential interest.

a) Lepra vitiligoide com lesões extensivas (Caso clinico) / b) Coexistencia de abcesso tuberculoso em doente de lepra (Caso clinico)

Os AA. apresentam dois casos clinicos. Em um deles as lesões vitiligoides de lepra eram tão extensas que o problema era a determinação das partes sans, normalmente pigmentadas e reagindo á histamina. No outro, de forma maculosa de aspéto clinico tuberculoide, notava-se um tumor na região epitrocleana direita, lembrando a caseose leprosa, mas provas bacteriologicas de inoculação em cabaio revelaram tratar-se de um abcesso tuberculoso de ganglio epitrocleano.