• hepatitis A (HAV);
  • hepatitis B (HBV);
  • hepatitis non-A;
  • non-B (NANB);
  • immunoglobulin M (IgM)

ABSTRACT— Ninety-three cases of acute viral hepatitis in adult Lebanese patients were followed-up prospectively for a period ranging from 6 to 18 months. These included 33 hepatitis A (HAV), 32 hepatitis B (HBV) and 21 non-A, non-B hepatitis (NANB) cases. The clinical and seroepidemiologic characteristics of the three types were evaluated. HAV was characterized by a short prodroma (<1 week) and a high IgM level. HBV did not differ from similar cases reported in the Western world except for a complete absence of male homosexuals and drug addicts as a possible route of transmission. NANB hepatitis in Lebanon is mainly a sporadic infection similar to HAV except that the prodromal phase is prolonged (>14 days) and IgM levels are within normal limits. The failure to develop chronicity in NANB suggests that the virus of sporadic NANB may be different from that which causes post-transfusional (PTH) NANB.