Reye's syndrome in children under three

A case of acute encephalopathy with fatty infiltration of the liver in a child was first described in 1929,1 but the association was not recognised as a clinicopathological entity until 1963.2 The syndrome was quickly recognised in several countries and attracted much clinical and pathological investigation.3-5 A conclusive diagnosis can be made on the findings of a severe acute neurological illness of unexplained origin with the characteristic fatty liver degeneration on histology.6 There is however, debate on whether other pathological indices of liver dysfunction, short of the morbid histology, are acceptable diagnostic criteria.7 The cause of Reye's syndrome (RS) is unknown, although epidemiological studies have suggested various factors including toxins, drugs, and infections possibly occurring in an individual with a geneticallydetermined metabolic abnormality.8 It occurs most often in school-aged children but the prognosis is worst in the younger age groups.9 10 Much of the available information about RS is derived from several large series of cases from North America11-14 and from the results of surveillance carried out by the Center for Disease Control,'5 based in Atlanta, Georgia. The neurological conditions studied by the National Childhood Encephalopathy Study (NCES)16 included RS, and therefore the cases notified provide an opportunity to investigate pathological, clinical, and epidemiological data on RS in young British children.