Unveiling the microbiological experience in exploring spinal TB cases from a tertiary care center

Spinal tuberculosis, a severe form of extrapulmonary tuberculosis, poses significant diagnostic and therapeutic challenges, often leading to neurological complications and deformity. Microbiological confirmation is crucial for diagnosis and effective treatment. We aim to evaluate the microbiological profile and diagnostic yield of various methods in spinal TB cases at a tertiary care centre and to correlate with clinical features and treatment outcomes.

A prospective study was conducted on samples from patients with suspected spinal TB (n = 58) from July 2023 to September 2024. All samples were processed using Ziehl-Neelsen (ZN) staining for acid-fast bacilli (AFB), culture on Lowenstein-Jensen (LJ) medium, BACTEC MGIT 960 liquid culture system, and GeneXpert MTB/RIF assay for rapid detection of MTB and rifampicin sensitivity. Relevant demographic, clinical, and radiological data were collected and analyzed. Based on susceptibility to drugs of culture isolates, treatment was started to see the outcome, and follow-ups were done with the patients.

A total of 19 spinal TB cases were microbiologically confirmed, out of 58 clinically suspected spinal TB cases, with a male predominance (57.9 %) and age range of 13-72 years. The most common symptom was lower back pain (89.5 %). GeneXpert was positive in all cases, detecting rifampicin resistance in 7(36.8 %). Culture was positive in 11 cases. ZN staining was positive in 15.8 % of direct samples. Histopathology showed granulomatous inflammation in 9 (47.3 %) of cases. MRI confirmed infective spinal involvement in 17(89.5 %) patients. MDR-TB regimen was initiated in 7 patients. Overall recovery was good, except one case of neuropathy and one mortality.

A combination of smear microscopy, culture, and molecular diagnostics significantly improves the microbiological diagnosis of spinal TB. GeneXpert offers rapid, reliable results, especially in rifampicin resistance detection. Early and accurate microbiological confirmation, coupled with clinical-radiological correlation, is essential for effective management and improved patient outcomes.