Tuberculosis of the central nervous system in children: 32 years survey

In order to study the impact of clinical and diagnostic parameters on the clinical outcome of children with central nervous system tuberculosis (CNS-TB), we retrospectively reviewed all cases of CNS-TB diagnosed over a 32-year period at the Children's Hospital of Palermo, Italy.

Data were collected with regard to the clinical, laboratory and demographic characteristics of patients, as well as the results of radiological investigations and data on clinical outcome. In relation to the date of introduction of new diagnostic methods (indirect as well direct) and to the change of treatment periods, the authors compared the clinical outcome of patients admitted prior and after 1984. They also classified the patients into 3 different stages of illness according to the severity of the disease on admission.

We identified 80 patients with CNS-TB. The mean age of the children was 3 years with 54% of patients younger than 5 years. The contact source was documented in 40 patients (50%). The mean duration of symptoms prior to admission was 22 days (range 5 days - 3 months). Mantoux skin test was positive on admission in 50 patients (62%). CSF smear microscopy and culture were positive in 29% and 45% of patients respectively. PCR for Mycobacterium tuberculosis introduced in 1994 was positive in 11 out of 13 tested patients. Determination of CSF gdT lymphocytes composition applied in 7 patients shows a predominance of Vg9/Vd2 T lymphocytes. Fifteen subjects (19%) died; 11 (13%) suffered from permanent sequelae. The died children and those with permanent sequelae were younger than the others (p<0.05). Prior to 1984, none of the patients were identified during early stage of illness and 4 out of 37 patients with stage II illness died. After 1985, 44% of children were in stage I and 2 out of 4 patients with stage III died (p<0.05).

Stage of disease and young age are still the decisive factors in the clinical outcome of children with CNS-TB. The availability of new advanced methods has improved the identification of patients with CNS-TB in stage I and therefore the possibility of an early treatment of such patients.