Fatores de risco para tuberculose pulmonar com confirmação bacteriológica, em Belo Horizonte, de 2006 a 2008

Abstract

Tuberculosis (TB) control is still defying the world. Brazil is one of the 20 high burden countries. Pulmonary TB is responsible for the maintenance of the dissemination of the disease. TB rates are particularly high in urban areas associated mainly with factors such as poverty, crowded living conditions, social instability and HIV infection. Objective: to evaluate risk factors for positive pulmonary tuberculosis in Belo Horizonte; to evaluate the levels of inflammatory markers C-reactive protein (CRP),albumin and lactate dehydrogenate (LDH) in pulmonary TB patients; to describe clinical and radiological manifestations of pulmonary TB in the same setting; to measure the resistance to chemotherapy in the studied group. Methods: design: matched case control study; patients with positive smear and controls from the same health unit matched by sex and age (± 5 years), with no respiratory symptom. Demographic data, domiciliary crowding, social status, smoking, history of sexuallytransmitted infections and use of illicit drugs, exposition to silica or to biomass smoke, blood transfusion, hepatitis, diagnosis of diabetes, contact with TB in the previous two years, previous TB, family history of TB and a validated version in Portuguese of the CAGE alcoholism screening test were investigated utilizing a structured questionnaire. Blood samples were drawn for the determination of glucose level and for HIV, hepatitis B and C serology. Chest radiographs (CXR) were examined. Sputum specimens were cultured. Results: Two hundred and twenty four cases and 224 controls were included. One hundred and fifty cases (67.0%) were male. Age of cases and of controls had mean of 39.3 (± 13.0) and of 39.5 (± 12.9) respectively. The conditional logistic regression model showed that alcoholism (OR = 6.65, IC 95% 5.74 - 7.56; p < 0.001), previous history of TB (OR = 6.43, IC 95% 5.31 - 7.56; p = 0.001), diabetes (OR = 5.90, IC 95% 4.70 - 7.10; p < 0.004), positive anti HBc IgG serology (OR = 5.15 IC 95% 4.22 - 6.08; p < 0.001), family history of TB (OR = 4.71, IC 95% 3.98 - 5.44; p < 0.001), tobacco smoking (OR = 4.36, IC 95%3.65 - 5.07; p < 0,001) and being not married (OR = 2.73, IC 95% 2.06 - 3.40; p = 0,003) were independently associated with pulmonary TB. C-reactive protein and albumin were significantly altered. Pulmonary manifestations occurred in more than 90% of the patients and systemic in more than 70%. Time from beginning of symptoms and diagnosis was 16.26 (± 18.75) weeks. CXR showed cavitations in 67.1% of cases. TBMR occurred in three of 158 of those who had sputum cultured (1,9%). Conclusion: Alcoholism, previous history of TB, diabetes, positive anti HBc serology, smoking, family history of TB, and being not married were risk factors for pulmonary TB. CRP and albumin may be used as markers of disease activity. Contrarily to what is thought to be, the sputum positive pulmonary TB may be a late diagnosed disease made when clinical presentation is advanced and cavitary lesions are frequent. Multiresistant TB was observed in 1.9%