Extensively Drug-resistant Tuberculosis of the Lumbar Spine in a Six-year-old Child: A Case Report

INTRODUCTION: The emergence of extensively drug-resistant tuberculosis (XDR-TB) is a challenging paradigm shift faced by the TB control programs worldwide today. The treatment is further compounded with unique management difficulties faced in pediatric patients. Treatment of XDR-TB requires prolonged chemotherapy with second-line drugs which offer lesser potency and increased risk of drug-related side effects. We present a case of spinal XDR-TB in a child, managed with extended second-line antitubercular chemotherapy (ATT). CASE REPORT: A 6-year-old, Caucasian male child complained of persistent back pain for 3 weeks, with lumbar tenderness without neurodeficit. Radiographs showed fourth lumbar (L4) vertebral body collapse. Magnetic resonance imaging showed features suggestive of TB spondylodiscitis. The erythrocyte sedimentation rate (ESR) was raised. In view of the high prevalence rate of TB, on clinical suspicion, empirical first-line ATT (isoniazid + rifampicin + ethambutol + pyrazinamide) was given for 6 months, under the Revised National Tuberculosis Control Program (RNTCP). In the course of ATT, child developed iliopsoas abscess which was drained surgically. Repeat radiological evaluation showed almost complete L4 body destruction and 10 cm × 8 cm pre-vertebral abscess. ESR was further raised. Vertebral biopsy culture showed growth of Mycobacterium tuberculosis complex susceptible only to capreomycin (Cm). Second-line ATT (moxifloxacin + clofazimine + linezolid + isoniazid + amoxicillin-clavulanate + para-aminosalicylic [PAS] acid) with daily intramuscular Cm was initiated, under the RNTCP Programmatic Management of Drug-Resistant TB initiative. At 3 months, tenderness was absent, ESR decreased, and radiology showed consolidation of L3 and L5 vertebral bodies and their interspace. At 6 months, injectable Cm was stopped, oral ATT continued for 18 months. No major drug-related side effects were noted. At final follow-up, imaging showed complete L4 body absence, intact posterior elements, surrounding bony consolidation, resolution of abscess without neurodeficit, or deformity. CONCLUSION: XDR-TB should be suspected if there is clinical and/or radiological progression of TB in spite of chemotherapy or a prior history of treatment for TB. Effective treatment of XDR-TB requires a high index of suspicion and prompt, aggressive drug sensitivity-based ATT.