Three suitable antigens for delayed-type hypersensitivity skin testing in a tropical country like Thailand.

Delayed type hypersensitivity (DTH) skin test is a standard tool to assess in vivo cell-mediated immunity. Mantoux method using 4-5 common recalled antigens is recommended. However, not all antigens are widely available and appropriate antigens for tropical countries are not known. The objective of this study is to investigate what and how many antigens should be included in the DTH testing panel that suitable for Thailand and may be for this region. The DTH skin tests were done by Mantoux method in a double blinded fashion. Average induration size of > or = 5 mm defined as a positive test. Antigens included purified protein derivative (PPD), Candida albicans, tetanus toxoid (TT), Trichophyton mentagrophytes and hepatitis B vaccine (HBV). The negative control was normal saline. Of 95 healthy subjects, all showed DTH positive to > or = 1 antigen. The positivity to C. albicans, tetanus toxoid, PPD, T. mentagrophytes, and HBV was 92.6%, 83.2%, 82.1%, 50.5%, and 5.3%, respectively. When three antigens: PPD, TT and C. albicans were analyzed, 100% of subjects showed a positive response to > or = 1 antigen and 96.8% showed a positive response to > or = 2 antigens. When only PPD and TT were analyzed, 100% of subjects showed > or = 1 antigen positive and 68.4% showed both antigens positive. C. albicans antigen at 1:100 was associated with a high incidence of fever (2/20) and large local reaction (7/20), 1:500 was found to be the optimal concentration. PPD, TT and C. albicans are suitable to be included in a DTH skin testing in a tropical country like Thailand. However, in a setting where C. albicans extract is not available, testing with only two antigens of PPD and tetanus toxoid may be an alternative, but with a lower sensitivity.

Incidência de onicomicoses no Pará entre 1980-1990 / Onychomycosis - incidence in the state of Pará, Brazil, between l980-1990

O autor faz um estudo sobre a incidência das onicomicose no Estado do Paraná no período de 11 anos (l980-l990), onde säo analisados os resultados de 3.772 exames micológicos. A maior freqüência foi observada em adultos do sexo feminino (69,67%). Quanto à profissäo predominou o grupo de prendas do lar (42.70%). T. rubrum (20%) e Candida albicans (30%) foram as espécies mais isoladas e os exames micológicos diretos mostraram maior positividade do que as culturas. Nessa pesquisa o autor entende que a doença deve ser investigada com maior atençäo considerando que as micoses superficiais ocupam o 1§ lugar na nosologia dermatológica da Amazônia, ao contrario das demais regiöes do país até entäo pesquisadas