Clinical correlates of CT abnormality in generalized childhood epilepsy in India

The CT scan gives valuable insight into the aetiology of epilepsy. Studies done so far in India suggest that the causes are quite different from the West. CT scan has become available in larger cities in India, but is expensive. Information about clinical features that may 'predict' a CT abnormality would be useful to clinicians. The object was to determine which, if any, of 10 clinical features predict a CT abnormality in patients presenting with generalized epilepsy. Consecutive children with generalized epilepsy were enrolled prospectively and clinical features charted. Predetermined clinical variables were compared in those with and without CT abnormality. The setting was a pediatric in-patients and out-patients of a teaching hospital in northern India. One-hundred-and-sixty-two out of 178 consecutive children (age 1 month to 12 years) presenting with generalized epilepsy; ten clinical features viz seizure type, age at onset, number of seizures, duration of epilepsy, family/antecedent history, mental/neurological deficit, abnormal EEG and evidence of tuberculosis, were studied. Univariate analysis taking (1) CT abnormality/no abnormality and (2) ring/disc enhancing lesion/no such lesion on CT as outcomes. An abnormal CT scan was found in 79 (49 percent) patients. There were two high yield groups: (1) younger children with neurological/mental deficits; (2) older children without deficits. When these two groups were combined, odds ratio for CT abnormality was 3.06 (1.4-6.7). The commonest CT abnormality was a ring/disc like enhancing lesion seen in 32 patients. Higher age at onset (> 4 years), absence of mental/neurological deficits, generalized tonic-clonic type of seizures and fewer episodes of seizures at presentation were significantly associated with this finding. In addition to existing indications for CT scan, these results can guide physicians when referring patients for this investigation.