Drug resistance patterns in 111 cases of drug-resistant tuberculosis spine

We report the largest study conducted till date of drug resistant tuberculosis in spine analyzing the drug susceptibility patterns in 111 cases of proven drug resistance. An observed cross-sectional study was conducted. Six-hundred and eighty-six patients with positive cultures underwent sensitivity testing to 13 commonly used anti-tubercular drugs using BACTEC MGIT-960 system. Females (60.3%) outnumbered males (39.6%). Only three patients (2.7%) were found HIV positive, and none of these had AIDS. Forty-four (39.6%) patients had taken AKT in the past for some form of tuberculosis. Eight (7.2%) patients had history of treatment default. The drug sensitivity testing revealed 87 (78.3%) cases of multi drug resistance (resistance to both isoniazid and rifampicin) and 3 (2.7%) cases of XDR-TB spine. Of the individual drugs, widespread resistance was present to both isoniazid (92.7%) and rifampicin (81.9%), followed by streptomycin (69.3%). Least resistance was found to kanamycin, amikacin and capreomycin. It is recommended to do routine biopsy, culture and drug sensitivity testing in all patients of tuberculosis spine to guide selection of appropriate second-line drugs when required. In cases of non availability of drug susceptibility testing despite repeated attempts, it is suggested to use data from large series such as this to plan best empirical chemotherapy protocol.