RT Journal Article
SR Electronic
T1 BCG vaccination is associated with decreased severity of tuberculosis in Karachi, Pakistan
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP P4463
VO 42
IS Suppl 57
A1 Nisar Rao
A1 Zahra Hasan
A1 Muhammad Irfan
A1 Javaid Khan
YR 2013
UL http://erj.ersjournals.com/content/42/Suppl_57/P4463.abstract
AB Background: Pakistan ranks 6th amongst high-burden countries worldwide and has an incidence of 231/100,000 population. Vaccination with Bacille Calmette–Gue'rin (BCG) is given at birth to protect against tuberculosis (TB) in Pakistan.Objective: To determine whether BCG has any protective effect against more severe forms of TB in Karachi, Pakistan.Material and Methods: This was a cross-sectional multi-center hospital-based study. TB patients (n = 218) with pulmonary (PTB, n = 120) or extrapulmonary (ETB, 98) were recruited, and the presence of a BCG vaccination scar was documented.Cases were further classified into minimal, moderate and advanced PTB or less severe (LETB) or severe disseminated (D-ETB) disease. The association of age, gender and severity of TB infections with BCG vaccination of the individual TB cases was investigated.Results:No difference was found of the BCG vaccination status of PTB and ETB cases, or in relation to age or gender. Patients under 29 years of age comprised the largest group. There were more females with ETB than PTB. The largest group within ETB comprised those with tuberculous lymphadenitis (LNTB, 39%). A significantly greater number of LNTB cases had received BCG vaccinations than had those with pleural (unilateral) TB (p = 0.004), and tuberculous meningitis (p = 0.027) groups. Also, there were more immunized patients with pulmonary as compared with pleural disease (p = 0.001).Conclusion:LNTB represents localized granulomatous disease and the observation of higher vaccination rates in this group suggests that BCG has protected against more severe forms of TB in this high-burden region.