Annual risk of tuberculous infection measured using serial skin testing, Orel Oblast, Russia, 1991-2005.

OBJECTIVE: To compare trends in direct annual risk of tuberculous infection (ARTI) during 1991-2005 in relation to tuberculosis (TB) incidence and to indirect estimates of ARTI derived from the prevalence of tuberculin skin test (TST) positivity in schoolchildren in Orel Oblast, Russia. DESIGN: In 2005, we abstracted annual TST results and vaccination histories from a representative sample of schoolchildren in Orel Oblast, Russia, where bacille Calmette-Guerin (BCG) vaccination and annual TST of children are nearly universal. We calculated direct ARTI based on the percentage of children tested with TST conversions each year, excluding conversions following BCG vaccination. RESULTS: We analysed records from 13 206 children, with a median of 10 recorded TST results per child. The ARTI increased from 0.2% in 1991 to 1.6% in 2000, paralleling trends in TB incidence. Similar results were observed when the ARTI was estimated based on prevalence of infection among children aged 3-5 years using a 12 mm cut-off to define TST positivity. Results differed substantially when 10 or 15 mm cut-offs were used or when prevalence was determined among children aged 6-8 years. CONCLUSION: ARTI measured through TST conversion increased as TB incidence increased in Orel Oblast. ARTI measured through serial TSTs can thus provide an indicator of changing trends in TB incidence.

Outcomes and follow-up of patients treated for multidrug-resistant tuberculosis in Orel, Russia, 2002-2005.

SETTING: Multidrug-resistant tuberculosis (MDR-TB) treatment facility, Orel Oblast, Russian Federation. OBJECTIVES: To determine factors associated with poor outcome and to document status of patients after recording of TB outcomes. DESIGN: Retrospective review of prospective single cohort. RESULTS: Among 192 patients, factors significantly associated with poor outcome in multivariate analysis include three or more treatment interruptions during the intensive phase of therapy and alcohol or drug addiction (adjusted OR [aOR] 2.1, 95%CI 1.0-4.3 and aOR 1.9, 95%CI 1.0-3.7). Previous treatment was associated with poor outcome, but only among smear-positive patients (aOR 3.1, 95%CI 1.3-7.3). Ten patients (5%) developed extensively drug-resistant TB (XDR-TB) during treatment; of 115 patients with at least 6 months of follow-up data after outcomes were recorded, 13 (11%) developed XDR-TB. CONCLUSION: Interventions focused on supporting patient adherence during the intensive phase of treatment; the management of drug and alcohol addiction should be developed and studied. A substantial proportion of patients developed XDR-TB during and after treatment. Longer term follow-up data of patients treated for MDR-TB are needed to better inform programmatic policy.