The majority of viruses which attack the liver tend to be associated with specific disease entities. However, in some cases there may be close resemblances to infectious hepatitis which may cause confusion. It has been known for some time that hepatocellular function is often impaired in infectious mononucleosis1 and, even in nonjaundiced patients, biopsy specimens may show changes by light microscopy simulating infectious hepatitis.2
Second, cytomegalovirus may produce an infection in adults resembling infectious mononucleosis,3 although it is more often associated with generalized cytomegalic inclusion disease in the newborn or in adults with underlying debilitating diseases. Biochemical evidence of liver damage and sometimes jaundice was obtained in all cases we studied.4,5
The ultrastructural pathology in infective hepatitis is well known,6,7 but there have been few descriptions of hepatic fine structure in other viral conditions. The present communication reports the findings in two cases, one of