Study objectives: To assess the incidence of
tuberculosis in the native and immigrant populations of southern Israel
in the period between 1992 and 1997, and to study the prevalence of
drug resistance overall and among these subpopulations in the region in
order to create guidelines for empirical antituberculous treatment in
Design: A retrospective population-based
Setting: The southern district of the country
and its tertiary-care hospital.
Patients: All new
culture-proven tuberculosis cases diagnosed in adults residing in the
Negev region during the study period. Patients were classified into
four groups according to ethnic origin and immigration date.
Results: During the study period, 249 new cases involving
249 patients were recorded. Immigrants from the former Soviet Union
(IFSU) were significantly younger and of male gender, and the incidence
among this group rose sharply. IFSU had higher rates of resistance to
any drug or drug combination. Isoniazid resistance rates were 16%
overall and 32% among IFSU. Resistance to any drug was observed in
29% overall and 50% of isolates among IFSU. Multidrug-resistant
tuberculosis was observed in 8.5% and 17%, respectively.
Conclusions: The population of southern Israel carries very
high rates of drug-resistant tuberculosis, mandating quadruple empiric
treatment. IFSU should be regarded as having multidrug-resistant
tuberculosis until proven otherwise, and empiric therapy with at least
five drugs should be considered. This report demonstrates the influence
of immigration on the incidence of tuberculosis, and the great value of
local surveillance of population-specific resistance rates in an
immigrant society, in order to optimize drug treatment and prevent the
dissemination of resistant strains.