What finding is characteristic of Reye syndrome in a liver biopsy?

Reye syndrome is associated with specific pathological changes in the liver, and microvesicular fatty infiltration is a hallmark finding in liver biopsies of affected individuals. This condition typically occurs in children, often following a viral illness, especially influenza or varicella (chickenpox), and is precipitated by the use of aspirin.

In the context of Reye syndrome, the accumulation of microvesicular fat within hepatocytes is prominent. This is characterized by small droplets of fat that accumulate in the liver cells, leading to cellular dysfunction without the significant inflammation typically associated with other liver conditions. The presence of microvesicular fat can impair lipid metabolism and mitochondrial function within the hepatocytes, contributing to the clinical picture of elevated liver enzymes, coagulopathy, and potential hepatic failure.

Understanding this characteristic finding aids in recognizing Reye syndrome, particularly in pediatric patients presenting with sudden onset of encephalopathy and liver dysfunction following a recent viral infection or aspirin use. Other findings associated with liver pathology may not be as definitive or pertinent in the context of Reye syndrome as microvesicular fatty infiltration is.