Tuberculosis of the spine in children - does drug resistance affect surgical outcomes?

The emergence of drug resistance has complicated the management of spinal tuberculosis (TB). While it is well known that the medical management of drug-resistant spinal TB is more difficult, the surgical outcomes of the same have not been studied sufficiently, particularly in children.

To analyze the surgical outcomes in a cohort of children treated for spinal TB, and to thus assess whether drug resistant (DR) disease is associated with poorer surgical outcomes.

Retrospective observational study.

All children diagnosed and treated for tuberculous spondylodiscitis at a single center between January 2014 and June 2017.

Surgical outcomes in terms of neurological status and kyphosis angle at final follow-up, and complication rates.

Radiographic and clinical data of children treated for spinal TB with minimum two-year follow-up were retrospectively analyzed. Data gathered included age, gender, level of spine affected, number of vertebrae involved, neurology (Frankel grade), microbiological reports, duration and type of anti-tuberculous therapy (ATT), details of Orthopaedic management and complications during treatment. In DR cases, the time from presentation to starting of second-line ATT was also assessed. Radiographs were reviewed to note the pre- and post-operative degree of kyphosis as well as the angle at final follow-up. Patients that developed major complications were compared statistically with those that did not.

Forty-one consecutive children (mean age 8.5 ± 4.2 years, 20 boys, 21 girls) were treated for spinal TB with a mean follow-up of 31.2 ± 6.4 months. Fifteen were managed conservatively, of which only one had DR-TB. Of the 26 managed surgically, 13 were managed with first-line ATT and 13 required second-line ATT. Of this latter group, eight had microbiologically proven drug resistance, whereas five were switched to second-line therapy presumptively because of failure to show an adequate response to first-line regimen. At last follow-up, all children had completed the prescribed course of ATT and had been declared cured. Neurological improvement was seen in all but one patient; and at last follow-up, 18 children were Frankel E, seven were Frankel D, and one was Frankel B. ¹The immediate post-operative Kyphosis angle averaged 24.38° ± 15.21°. However, six children showed a subsequent worsening of kyphosis, and the Kyphosis angle at last follow-up averaged 30.96° ± 23.92°. Five children had major complications requiring revision surgery; complications included wound dehiscence, vertebral collapse, screw pull-out and implant breakage. Significantly higher number of patients in the group with complications had required second-line ATT (p < .05).

In a cohort of children treated surgically for spinal tuberculosis, a higher complication rate, and thus poor surgical outcomes, were found to be associated with drug resistant disease.