Extrapulmonary Tuberculosis: Mycobacterium tuberculosis Strains and Host Risk Factors in a Large Urban Setting in Brazil

Abstract

BackgroundFactors related to the development of extrapulmonary forms of tuberculosis (EPTB) are still poorly understood, particularly in high-endemic countries like Brazil. The objective of the paper is to determine host and Mycobacterium tuberculosis (MTB) strain-related factors associated with the development of EPTB in Espírito Santo state, Brazil.Methods and FindingsWe conducted a retrospective laboratory-based surveillance study of new tuberculosis (TB) cases diagnosed in Espírito Santo state, Brazil between 1998 and 2007. We genotyped 612 isolates of MTB from 606 TB patients using spoligotyping and IS6110-restriction fragment length polymorphism (RFLP) typing and compared sociodemographic and clinical characteristics of patients with pulmonary TB (PTB) and EPTB. Among 606 patients, 464 (77%) had PTB, 79 (13%) had EPTB, 51 (8%) had both, and 12 (2%) had miliary TB. The IS6110 RFLP analysis demonstrated that 250 (41%) isolates belonged to clustered RFLP patterns, 27 (11%) of which were from EPTB. We identified 73 clusters including 35 (48%) composed of 2 isolates each. By spoligotyping, 506 (83%) MTB isolates fell into known patterns and 106 (17%) fell into patterns with no family assignment; 297 (48%) isolates belonged to the Latin-American Mediterranean family. Higher school level (4-7 years OR: 0.16 95% CI 0.34-0.73 and > 8 years of education, OR 0.06 95% CI 0.009-0.50) white ethnicity (OR: 2.54 95% CI 1.03-6.25) and HIV infection (OR: 16.83 95% CI 5.23-54.18) were associated with EPTB. No specific strain lineage or percentage of clustering was associated with EPTB.ConclusionsThese results demonstrate that risk factors for EPTB are related more to host than to MTB strain lineage characteristics.

Association of HIV infection with extrapulmonary tuberculosis: a systematic review

“…Using the modified Newcastle-Ottawa criteria ( Appendix Table 1 ), four of the studies [17, 20, 25, 29] had a low risk of bias, ten [18, 19, 21, 22, 24, 26-28, 30, 31] had a medium risk of bias and two [23, 11] had a high risk of bias. Despite the cross-sectional design, studies by Wilkinson and Moore; Gonzalez et al; Fiske et al; and Sama et.…”

“…High heterogeneity remained in another sensitivity analysis where EPTB was defined as “EPTB only” (“EPTB+ PTB” cases were excluded from the analysis). When the Gomes paper [19] was excluded in another sensitivity analysis because it had much higher estimates of the odds ratio compared to other studies, high heterogeneity persisted (data not shown).…”

Factors associated with mortality in extrapulmonary tuberculosis patients at a teaching hospital in Ghana

“…1 It is widely reported that EPTB occurs more frequently in immunocompromised patients. 8,15,16 EPTB accounts for more than 50% of tuberculosis cases in HIV/AIDS patients as compared to 15-20% of TB cases in immunocompetent patients. 10,17 In fact, EPTB is considered an AIDS defining disease.…”

Clinical and Sociodemographic Risk Factors for Tuberculosis in Human Immunodeficiency Virus Infected Patients

“…Factors most frequently found are: poverty, malnutrition, overcrowding, lack of ventilation and lighting in homes, alcohol, smoking and other drugs, pregnancy, corticosteroids use, lack of access to merg services and presence of other associated conditions such as diabetes (Gomes et al, 2013). Household contacts with TB infected merg also a known and risk factor for development tuberculosis, especially in endemic areas (Fox et al, 2013).…”

“…Household contacts with TB infected merg also a known and risk factor for development tuberculosis, especially in endemic areas (Fox et al, 2013). HIV infection has joined the long list of risk factors and confers increased risk for active Tb (Gomes et al, 2013).…”