Consideration. is gzven to the recognition and prevention of carious types of mental retardation due to hazards of environmental origin. Observations are presented on congenital syphilis, congenital toxoplasmosis, congenital rubella, Singapore kernicterus, Japanese B encephalitis, and tuberculous meningitis. Appropriate preventiue measures have resulted in a significant reduction in Singapore of these conditions, and hence in a decreased frequency of environmentally determined mental retardation. and related disabilities.
A 17-year-old man from Sarawak presented with acute encephalitis syndrome. Serologic testing revealed raised Japanese Encephalitis (JE) IgM antibody titre in which first serum JE was negative followed by positive second serum JE IgM one week later. Magnetic resonance imaging (MRI) and Magnetic resonance venogram (MRV) showed cerebral venous sinus thrombosis (CVST) which is a rare presentation of JE. Early identification of CVST is important as anticoagulation needs to be started to reduce adverse neurological sequelae and improve prognosis.