Tuberculin skin testing in HIV-infected patients in Campo Grande, Mato Grosso do Sul State, Brazil

Abstract

A cross-sectional study on HIV/AIDS was carried out in 108 outpatients from the university hospital of the Federal University of Mato Grosso do Sul, Campo Grande, Brazil, from July to December 2008, to investigate latent tuberculosis infection using the tuberculin skin test (TST). The prevalence of positive results was 13.9%. The CD4+ T cell count (p = 0.091) and the diagnosis time (p = 0.010) were statistically significant when compared with TST positivity. In the cohort of HIV/AIDS patients who had latent tuberculosis infection, the median diagnosis time was eight years. Undetectable viral load presented significant association (p = 0.046) with tuberculosis infection. The fact that numerous individuals with HIV/AIDS infection presented a negative reaction to the tuberculin skin test is probably related to alterations in the cellular immune response induced by HIV infection. The tuberculin test is a useful tool for the detection of latent tuberculosis infection and should be performed in all HIV/AIDS individuals at the time of the diagnosis and on a yearly basis, if negative. Both the early identification of the tuberculosis infection by the tuberculin skin test at the moment of immunological restoration and chemoprophylaxis in infected individuals are mechanisms to control HIV/AIDS and tuberculosis coinfection

Indicação da prova tuberculínica e infecção latente da tuberculose em HIV-positivos, Município de Blumenau, Estado de Santa Catarina, Brasil, 2004-2009

“…Sabe-se que a TARV reduz a incidência de TB em até 80% e a adição do tratamento da ILTB a esse controle reduziria a incidência em mais 58,0-70,0%. [10][11][12] Desde a década de 1960, diversos ensaios clínicos, placebo-controlados e duplo-cegos vêm demonstrando a eficácia da isoniazida como medicamento profilático para pacientes com ILTB. 1,[13][14][15] O tratamento da ILTB não previne a progressão da imunodeficiência causada pelo HIV ou a incidência de doenças definidoras de aids, contudo possui impacto sobre a mortalidade dos indivíduos reatores à prova tuberculínica.…”

“…9,12,17 A prova tuberculínica (PT), realizada pelo inóculo do derivado proteico purificado (PPD) na técnica de Mantoux é, ainda hoje, o teste de escolha para o diagnóstico dos pacientes com ILTB. 1,6,11 As recomendações do Ministério da Saúde esclarecem que os indivíduos HIV+ devem realizar a PT no momento do diagnóstico de HIV/aids e anualmente, caso sejam não reatores (enduração <5mm). Quando reatores (enduração ≥5mm) e na ausência de tuberculose como doença ativa, o paciente tem uma indicação precisa da realização da quimioprofilaxia com isoniazida 300mg/dia, via oral, autoadministrada, de 6 a 9 meses.…”

Teste tuberculínico: pesquisa operacional no Mato Grosso do Sul

“…Among those patients, the prevalence of latent tuberculosis was found to be 13.9%. (11) In the DSEI/SESAI, the TST coverage was high, as was that of latent tuberculosis treatment, both of which were provided at a rate far greater than that observed in the general population. In the TCP of the DSEI/SESAI, the operational aspects were well managed, as they were at the abovementioned PCC.…”

“…(18,22,(24)(25)(26) Although studies conducted in Brazil and abroad found considerable evidence to support the recommendation that health care students and workers be screened for latent tuberculosis (at admission/hiring and annually), our survey found that this screening has not been performed, which makes it impossible to treat this at-risk population prophylactically. (11,14,27) Health care workers in the state of Mato Grosso do Sul were screened by the TST only once, in 2004, and the prevalence of latent tuberculosis was found to be 37.8%. However, the screening did not result in annual follow-up evaluations or in preventive treatment in cases of TST conversion.…”

“…(1,8) The preventive approach prioritizes individuals who are immunocompromised or are receiving immunosuppressive therapy, children younger than two years of age, and the elderly, as well as health care workers and medical students, who are at a higher risk of becoming infected because of occupational exposure. (9)(10)(11)(12)(13) Latent tuberculosis treatment with isoniazid plays a fundamental role in tuberculosis control and can prevent active tuberculosis in 60-90% of the cases. (13,14) Operational difficulties in identifying latent tuberculosis constitute major obstacles to the implementation of preventive therapy with isoniazid.…”