[Molecular analysis of strains from tuberculosis patients in Polish prisons in 2004-2008. Initial analysis of the project].

INTRODUCTION: Correctional facilities are recognised breeding ground for infectious diseases. As The World Health Organization reported the incidence of infectious diseases in prison's population is 10-100 times higher than in general population. The incidence of tuberculosis among correctional inmates in Poland in 2008 was 270/100000, that is around 10 times higher than among non-prisoners.
MATERIALS AND METHODS: The study included 57 M. tuberculosis isolates from patients in Polish prisons in 2004-2008 (5% of all diagnosed TB patient in Polish prisons 2004-2008). Primary isolation was performed with Löwenstein-Jensen (L-J) medium, species identification was done with the niacin test and gene probes test. Bacterial DNA was extracted from the L-J medium slants with the cetyltrimethylammonium bromide (CTAB) method. Mycobacterium tuberculosis strains were analyzed with two methods: screening for epidemiological discrimination of M. tuberculosis - spoligotyping and high-throughput - MIRU/VNTR.
RESULTS: Isolates that are grouped in clusters (33 isolates) were analyzed by means of MIRU/VNTRs. In MIRU/VNTRs all strains showed different genetic patterns. Most isolates of the prisoners were grouped into two clusters: T1 53 and H3 50.
CONCLUSIONS: 1. MIRU/VNTR is a high-throughput method. 2. MIRU/VNTR is a promising method to diagnose TB transmission in Polish jails. 3. To identify the probable source of transmission, molecular analysis of strains from patients of the general population is needed.