An appraisal of epidemiologic, clinical, bacteriologic, histopathologic, and immunologic parameters in cutaneous tuberculosis.

Cutaneous tuberculosis incidence was recorded as 0.15%. Of the 42 patients, 23 had scrofuloderma, 17 lupus vulgaris, and 2 tuberculosis verrucosa cutis. Both men and women were affected by the disease in the second and third decades. Its duration was variable. An affirmative family history was elicited in five scrofuloderma patients. The clinical expression largely conformed to the ritual text. Variation in Mantoux test positivity was unremarkable. The disparity in the demonstration of bacilli in the smear and tissue sections was, however, quite apparent in scrofuloderma. The correlation of different parameters indicates a continuous spectrum, formed at one end by lupus vulgaris, and at another by scrofuloderma. A moderate to strongly positive Mantoux text, enormous lymphocytes in the granuloma, absence of tubercle bacilli, negative culture, and an apparently normal immunoprofile were features of lupus vulgaris; whereas scrofuloderma had a moderately positive Mantoux test, lesser number of lymphocytes in the granuloma, large number of bacilli in tissue smear and/or tissue section, raised levels of immunoglobulins, and a grossly lowered C3 levels. The other variants probably occupy a position in between.