Dengue haemorrhagic fever in a child presenting as encephalitis on day one of fever.

A nine-year old boy presented on first day of fever with behavioural change, headache and vomiting. He was immunised against Japanese encephalitis. Examination revealed an obese, febrile, drowsy and disoriented child with neck stiffness. His eye opening was spontaneous, spoke inappropriate words and localised the pain. Glasgow coma scale was 12. Cardiovascular, respiratory and abdominal examinations were normal. His blood sugar and serum electrolytes were normal. The white cell count was 16.1106/l (N 71%, L 22%). The haemoglobin was 13 g/dl, haematocrit was 39.7% and platelet count was 332106/l.