“…Frequent hepatic involvement in infectious mononucleosis has been shown by liver biopsy (Nelson and Darragh, 1956;Sullivan, Irey, Pileggi, Crone, and Gibson, 1957), conventional liver function tests (Wechsler, Rosenblum, and Sills, 1946;Schultz and Hall, 1952;Mason and Adams, 1958), and serum transaminases (Sullivan et al, 1957;Rosalki, Jones, and Verney, 1960) and other enzymes (Kalk, Schmidt, Schmidt, and Wildhirt, 1960). We consider that the abnormal enzyme findings in infectious mononucleosis are due to almost universal hepatocellular damage; neither serum I.C.D.…”