[Resistance to second-line drugs in migrants with multidrug-resistant tuberculosis in the Berlin region]

The empiric therapy of multidrug-resistant (MDR) tuberculosis (TB) after rapid molecular testing is rendered difficult by an often several weeks-long period of uncertainty, because results of susceptibility testing for second-line TB drugs are pending. The analysis of regional resistance patterns could lead to a more targeted empiric treatment for migrants depending on their country of origin. The results of the susceptibility testing from 2008 to 2013 of all mycobacteria sent to the Institute of Microbiology, working with the department of Pneumology, Heckeshorn Lung Clinic, Berlin, were reanalysed and tested for regional differences. We found 39 multidrug-resistant Mycobacterium tuberculosis strains among the examined strains. More than half of these strains tested susceptible to the following second line drugs namely, linezolid (97%), clofazimine (95%), cycloserine (95%), capreomycin (90%), p-aminosalicylic acid (82%), moxifloxacin (79%) and amikacin (79%). The proportion of strains susceptible to pyrazinamide (44%), ethambutol (28%), prothionamide (15%), rifabutin (8%) and streptomycin (8%) was lower. The mycobacterial cultures of the Chechen patients (n = 14) showed significantly different susceptibilities to amikacin (57%) and prothionamide (36%) compared to the strains from migrants of other regions. In this study, the regional differences in mycobacterial susceptibility to second line drugs suggest that the initial MDR TB therapy of migrants should be tailored to their country of origin.