Case 41.  EBV hepatitis (infectious mononucleosis) (24 y-o M)
         
    Liver biopsy from a young adult showing fever, skin rash and moderate liver dysfunction    
         
   
Key words :  infectious mononucleosis, EB virus, hepatitis
   
     
 
     
Histologic features of acute EBV hepatitis are nonspecific. Mild portal and lobular inflammation is observed (HE).   EBER-1 (EBV-related small nuclear RNA) is demonstrated in the nucleus of a few hepatocytes (in situ hybridization).
     
 
     
Reference case 41A
Autopsied liver in case of EBV-related fulminant hepatitis in a 27 y-o man (HE). Massive hepatocellular necrosis is seen in the lethal EBV activation.
  Reference case 41B
Infectious mononucleosis, showing epipharyngeal swelling in a 10 year-old boy (biopsy, HE). Atypical lymphoid cells are observed in the necrotic background. The large-sized lymphcytes express T-cell phenotypes.
     
 
     
Reference case 41B
Infectious mononucleosis, showing epipharyngeal swelling in a 10 year-old boy (biopsy, HE). In the non-necrotic part of the epipharynx, activated atypical lymphocytes are intermingled with small lymphocytes.
  Reference case 41B
Infectious mononucleosis, showing epipharyngeal swelling in a 10 year-old boy (biopsy, HE). EBER-1 is demonstrated in the nuclei of small-sized B-cells, while the activated T-cells are negative. The lesion diminished in size in one week.
     
   
     
Reference case 41C
Acute CMV hepatitis. Liver biopsy after liver transplantation from a live mother (HE). The appearance of clustered neutrophils within the liver lobule strongly suggests cytomegalovirus infection in this situation.