Acute necrotizing encephalopathy of childhood: an under-recognized and diverse clinico-radiological syndrome

Background: With advances in neuroimaging, acute necrotizing encephalopathy of childhood (ANEC) is being recognized as an acute encephalopathy with a characteristic rapidly deteriorating neurological course with poor neuro-developmental outcomes with high mortality and morbidity rates. Indian data of ANEC is primitive and hence this study was planned. The objective of the study was to evaluate the clinical, radiological characteristics and its outcomes in children with ANEC.Methods: Retrospective review of 10 infants and children with ANEC at Department of Paediatrics, S.N. Medical College and HSK Hospital, Bagalkot from January 2013 to December 2019. ANEC was suspected based on clinical and radiological characteristics and diagnosis was made based on diagnostic criteria proposed by Mizuguchi et al. Clinical and radiological (Magnetic resonance imaging (MRI) brain characteristics) findings and response to early pulse dose steroid therapy and supportive treatment were assessed in all cases. All cases were followed for evaluation of neurodevelopmental outcome and response to physiotherapy was noted in all the cases.Results: Total 10 cases were analysed (age ranged from 6 months to 11 years). Sex distribution male to female was 3:7. All cases had precedent viral illnesses and had fever, coryza, diarrhoea. The initial neurological symptoms included seizures and status epilepticus (n=7), altered sensorium (n=3), focal neurological signs , gait disturbances (n=2) and diplopia (n=1). MRI brain revealed characteristic thalamus involvement with varied involvement of midbrain, pons, medulla (n=10). Other findings were cavitation (n=5), haemorrhage (n=4), minimal residual lesions (n=4), cerebral atrophy (n=1), normal brain study (n=5) on follow-up. 9 out of 10 cases survived, responded to early physiotherapy and rehabilitation. 6 children had complete recovery with minimal disability in 3 cases.Conclusions: ANEC is a clinico-radiological syndrome. Early detection and appropriate treatment improves outcome in ANEC.