Background
Much of the neurological sequelae of central nervous system (CNS) tuberculosis (TB) is due to an excessive cytokine-driven host-inflammatory response. Adjunctive corticosteroids, which reduce cytokine production and thus dampens the inflammation, improve overall survival but do not prevent morbidity. This has prompted investigation of more targeted immunomodulatory agents, including thalidomide.

Methods
We describe a retrospective cohort of 38 children consecutively treated with adjunctive thalidomide for CNS TB-related complications over a 10-year period

Results
The most common presenting symptom was focal motor deficit (n=16), followed by cranial nerve palsies and cerebellar dysfunction. Three of the 38 children presented with large dural-based lesions, manifesting as epilepsia partialis continua (EPC), 4 presented with blindness secondary to optochiasmatic arachnoiditis whilst two children developed paraplegia due to spinal cord TB mass lesions. Duration of adjunctive thalidomide therapy (3-5 mg/kg/day) varied according to complication type. In children compromised by TB mass lesions, the median treatment duration was 3.9 months (interquartile range [IQR]: 2.0-5.0); whilst in children with optic neuritis it was 2.0 months (IQR: 1.3-7.3) and in EPC it was 1.0 months (IQR: 1-2.5). Satisfactory clinical and radiological response was observed in 37 of the children. None of the children experienced rashes, hepatitis, hematologic derangements or complained of leg cramps.

Conclusion
This study is the largest cohort of adult or paediatric patients treated with adjunctive thalidomide for CNS TB-related complications. The drug has proved safe, well tolerated and appears to be clinically efficacious. The potential role of thalidomide or analogues in the treatment of other TBM-related complications requires further exploration.