The patient was 46 years old and had no pathological history, but 2 months before the consultation had inflammatory-type lumbar pain that developed in the context of deterioration of general condition. The interrogation revealed a possibility of tuberculous contagion 6 months before, and the clinical examination revealed lumbar pain on palpation and spinal stiffness without neurological attack. Abdominal-pelvic computed tomography (CT) showed spondylodiscitis at the level of the 10th, 11th and 12th dorsal vertebrae and the first lumbar vertebra with bilateral abscess collections at the expense of both psoas muscles (Fig. 1). The chest X-ray was normal. The biological assessment showed a C-reactive protein (CRP) level of 58 mg l-1 and a sedimentation rate of 60 mm/first hour, while the HIV serology was negative and the interferon gamma release assay (IGRA) test (Quantiferon) was positive.
The patient benefited from scanned/guided drainage and the pus brought back was subjected to bacteriological study (culture on blood agar and chocolate agar incubated at 37  C in an aerobic and anaerobic atmosphere). This culture remained sterile after 4 days of incubation. For direct examination after Ziehl-Armand staining in search of acid-fast bacilli, the result was negative. The real-time PCR-based  Mycobacterium tuberculosis  test on the GeneXpert MTB/RIF system (which also makes it possible to detect rpoB gene mutations associated with rifampicin resistance), the system did not detect any mutations, so the strain was sensitive to rifampicin. A culture grown on solid Lowenstein-Jensen medium developed a month later (Fig. 2), while a culture grown in liquid medium (VersaTREK broth Myco Broth) and incubated in the VersaTREK automaton, whose technology is based on the detection of oxygen levels consumed by the mycobacteria, became positive after 20 days. When the susceptibility of the isolated strain to rifampicin, isoniazid and ethambutol was studied using the liquid dilution method on the versaTREK automaton, the strain was found to be sensitive to these antibiotics.
Following these results, the patient was put on rifampin, isoniazid, ethambutol and pyrazinamide for a duration of 2 months and rifampin and isoniazid for 10 months. The evolution was favourable, with weight recovery, loss of pain and decrease in CRP and sedimentation rate.