RT Journal A1 Bar RS, Adlard J, Thomas FB T1 LYmphopenic infectious mononucleosis JF Archives of Internal Medicine JO Archives of Internal Medicine YR 1975 FD February 1 VO 135 IS 2 SP 334 OP 337 DO 10.1001/archinte.1975.00330020138019 UL http://dx.doi.org/10.1001/archinte.1975.00330020138019 AB Infectious mononucleosis (IM) is thought to be a benign lymphoproliferative disease defined by characteristic clinical, hematologic, and serologic features.1 The established laboratory criteria for the diagnosis of IM include positive heterophil reactions, absolute lymphocytosis with increased numbers of atypical forms, and elevated titers of Epstein-Barr viral (EBV) antibodies.1,2 We describe two unique cases of IM, one with fulminant pancreatitis, hepatitis, myocarditis, clinical shock, and renal insufficiency and the other with severe hepatitis that progressed to chronic aggressive hepatitis. The two cases reported herein are distinctly unusual forms of IM in two respects: (1) both were associated with severe lifethreatening complications and (2) both patients came to us with absolute lymphopenia.PATIENT SUMMARIES  Patient 1.  —An 18-year-old female college student developed malaise, nausea, and daily fevers to 40 C (104 F) orally. These symptoms persisted for approximately two weeks, then gradually cleared up in four to seven days. During