Factors associated with the presence of tuberculosis in patients with acquired immunodeficiency syndrome in Cuba

To determine the factors associated with the development of tuberculosis in patients with acquired immunodeficiency syndrome (AIDS) and to identify the most frequent symptoms and signs of tuberculosis in this group of patients. This retrospective observational case-control study was carried out with 143 patients diagnosed with AIDS who were discharged from the Pedro Kourí Institute of Tropical Medicine, which is in the city of Havana, Cuba, between January 1997 and March 2001. The cases were 72 patients with AIDS and some clinical form of tuberculosis, while the control group was made up of the first 71 AIDS patients without tuberculosis who were discharged. The following variables were evaluated: AIDS stage before the study, serious opportunistic infections suffered before the diagnosis of tuberculosis (pulmonary pneumocystosis, cerebral toxoplasmosis, systemic candidiasis, isosporiasis, and recurrent pneumonia), concentration of CD4+ T lymphocytes, and clinical symptoms and signs of tuberculosis. The primary data were taken from the clinical files of the patients. We calculated the frequency of the nominal qualitative variables and the crude odd ratios (ORs) and their 95% confidence intervals (CIs). The statistical association among the variables was determined with the chi-square test with Yates correction. The individual effect of each variable was assessed through multivariate logistic regression analysis. The level of statistical significance was 0.05. Tuberculosis in this group of patients showed a statistically significant association with: being ill with AIDS before the study (OR = 3.57; 95% CI: 1.78 to 7.17); a history of pulmonary pneumocystosis (OR = 4.73; 95% CI: 1.51 to 15.76), cerebral toxoplasmosis (OR = 6.22; 95% CI: 1.21 to 42.99), or systemic candidiasis (OR = 11.29; 95% CI: 1.40 to 246.5); and having CD4+ T lymphocyte concentrations lower than 200 cells/mm(3). However, the logistic regression showed a significant association only with the history of systemic candidiasis (OR = 10.47; 95% CI: 1.06 to 103.5; P = 0.0446). The symptoms associated with the clinical diagnosis of tuberculosis were hemoptysis (OR = 7.54; 95% CI: 1.88 to 170.34), fever of unknown origin (OR = 13.38; 95% CI: 5.55 to 32.96), night sweats (OR = 21.95; 95% CI: 4.66 to 142.43), and weight loss (OR = 3.52; 95% CI: 1.65 to 7.55). The associated signs were regional lymphadenopathies (OR = 10.00; 95% CI: 1.22 to 220.3), hepatomegaly (OR = 5.44; 95% CI: 1.76 to 17.95), and