Tuberculosis associated with diabetes mellitus by age group in Brazil: a retrospective cohort study, 2007-2014

ABSTRACT Diabetes mellitus (DM) has important implications for tuberculosis (TB), as it increases the risk for disease activation and is associated with unfavorable TB treatment outcomes. This study analyzed the association between TB and DM (TBDM) in Brazil from 2007 to 2014. This was a retrospective cohort study carried out in 709,429 new cases of TB reported to the national disease notification system of the Brazilian Ministry of Health. Sociodemographic and clinical data, test results, and treatment outcomes were analyzed. TBDM was found in 6.0% of TB cases, mostly in men aged 18-59 years. The lethality rate was 5.1% higher in all age groups with diabetes, except in those older than 60 years of age. The frequency of multi-drug-resistant tuberculosis (MDR-TB) in patients with DM was higher in those without DM, with a 1.6- to 3.8-fold increase in the odds of MDR-TB. The elderly showed an increase in the prevalence of TBDM from 14.3% to 18.2%. Women were more likely to have DM, and elderly women had 41.0% greater chance of having DM. Relapse was significant among patients younger than 17 years of age. TBDM was high in Brazil, affected all age groups, and was associated with unfavorable TB treatment outcomes. We emphasize the need for strategies for the clinical management of diabetic tuberculosis patients in Brazil aiming at minimizing relapses, deaths, and MDR-TB.

PKO: alternative method for isolating mycobacteria from sputum

We elaborated an alternative culture method, which we denominated PKO (initials in tribute of respect to Petroff, Kudoh and Ogawa), for isolating Mycobacterium tuberculosis from sputum for diagnosis of pulmonary tuberculosis (TB), and to compare its performance with the Swab and Petroff methods. For the technique validation, sputum samples from patients suspected of pulmonary TB cases were examined by acid-fast microscopy (direct and concentrated smear), PKO, Swab and Petroff methods. We found that Petroff and PKO methods have parity in the effectiveness of M. tuberculosis isolation. However, by the PKO method, 65 percent of isolated strains were detected in a period of £15 days, while by the Petroff method the best detection was in an interval of 16-29 days (71 percent). In positive smear samples, the average time of PKO isolation is only superior to the one related for Bactec 460TB. In conclusion, the exclusion of the neutralization stage of pH in the PKO reduces the manipulation of the samples, diminishes the execution time of the culture according to the Petroff method and facilitates the qualification of professionals involved in the laboratorial diagnosis of Tuberculosis.

Foi elaborado um método de cultivo alternativo, denominado por nós PKO (iniciais referentes à Petroff, Kudoh e Ogawa), para o isolamento do Mycobacterium tuberculosis em amostras de escarro para o diagnóstico da tuberculose pulmonar (TB). Para validação da técnica, amostras de escarro de pacientes suspeitos de TB foram submetidas aos métodos de baciloscopia (direta e pós-concentração), PKO, Swab e Petroff. A análise comparativa entre o método de Petroff e o PKO mostrou paridade de resultados em relação ao isolamento e número de colônias de M. tuberculosis. Porém, pelo método PKO, 65 por cento das cepas isoladas foi detectada em um período £15 dias, enquanto que pelo método de Petroff a melhor detecção ocorreu em um intervalo de 16-29 dias (71 por cento). O tempo médio de isolamento pelo PKO é somente superior ao sistema comercial Bactec 460TB em amostras positivas na baciloscopia. A exclusão da etapa de neutralização de pH no método PKO reduz a manipulação das amostras, diminui o tempo de execução do cultivo em relação ao de Petroff e facilita o treinamento de profissionais que realizam o diagnóstico laboratorial da TB.

Qualidade do exame baciloscópico no Distrito Federal (Brasil): uma averiguação da confiabilidade / The quality of the baciloscopic test in Distrito Federal (Brazil): an inquiry about its reliability

No Brasil, uma das prioridades do plano de combate à tuberculose é a avaliação de desempenho laboratorial através do controle de qualidade das baciloscopias. Este estudo objetivou avaliar a confiabilidade dos exames realizados pelo Programa de Tuberculose do Distrito Federal (PCT-DF). Trata-se de um estudo descritivo, realizado a partir das lâminas revisadas no laboratório de referência, de 1988 a 1999. Comparou-se em dupla cega os resultados das leituras dos esfregaços obtidos na periferia e laboratório central. As concordâncias/discordâncias foram analisadas pelo Kappa e intervalo de confiança (IC). Avaliaram-se 7.756 lâminas, obtendo-se discordâncias de 1,9 por cento de falso-positivas e de 0,8 por cento falso-negativas. Até 1997, 66,5 por cento das baciloscopias positivas foram revisadas. Implementada essa atividade, atingiu-se 90,1 por cento. A confiabilidade foi ótima pelo Kappa, discordando com os resultados do IC. O controle de qualidade deve ampliar a confiabilidade do diagnóstico de tuberculose, entretanto, a avaliação depende do uso de testes de reprodutividade sensíveis.