Reye's syndrome-histological finding-

Reye's syndrome is defined as an acute postviral syndrome of encephalopathy and fatty change in the viscera. The syndrome may follow almost any known viral disease but is most common after influenza A or B and varicella. Viral infection may act singly, but more often its effect is modified by ceain exogenous factors such as by administration of salicylates, aflatoxins, and insecticides. These effects causemitochondrial injury and decreased activity of mitochondrial enzymes in the liver. This eventually leads to rising in blood ammonia and accumulation of triglycerides within hepatocytes.The patients are generally children between 6 months and 15 years of age. Within a week after a viral illness, the childdevelops intractable vomiting and progressive neurological deterioration due to encephalopathy, eventually leading tostupor, coma, and death. Characteristic laboratory findings are elevated blood ammonia, serum transaminases, bilirubinand prolonged prothrombin time.Microscopically, hepatocytes show small droplets ofneutral fat in their cytoplasm (microvesicular fat). Similarfatty change is seen in the renal tubular epithelium andin the cells of skeletal muscles and hea. The brain showsedema and sometimes focal necrosis of neurons. HARSH MOHAN Textbook of pathology 6th edition pg no 602