OBJECTIVETo analyse the proportion of hepatitis associated aplastic anemia (HAAA) in severe aplastic anemia (SAA) and its clinical features of HAAA.

METHODSAll newly diagnosed SAA cases in our department in the recent 5 years were analyzed. A case-control study was undertaken to investigate the differences of clinical and laboratory features between HAAA and non-hepatitis associated SAA (non-HASAA) patients.

RESULTSThe proportion of HAAA in SAA was 3.3%. There was no significant difference in PB cell counts, bone marrow hematopoiesis status and the amount of blood transfusion between HAAA and non-HASAA patients. Sera from 13 patients with HAAA were tested for antibodies to hepatitis viruses A, B, and C and hepatitis B surface antigen. Twelve (92.3%) of them had negative serologic results for the tests and only one (7.7%) had a positive result for HBsAg and HBeAg. Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were decreased prior to the diagnosis in twelve (92.3%) of the 13 HAAA patients. The percentage of CD4(+) cells in HAAA patients was significantly lower than that in non-HASAA patients (P < 0.05). HAAA patients had higher percentages of CD8(+) cells (P < 0.05) and lower ratios of CD4(+)/CD8(+) (P < 0.05). The early infection rate of the HAAA patients was significantly higher than that of non-HASAA patients (84.6% vs 42.3%, P < 0.05), with different mortalities (61.5% vs 15.4%, P < 0.05). The 2-year survival rate of HAAA patients was significantly lower than that of non-HASAA patients (16.6% vs 83.2%, P < 0.01).

CONCLUSIONThe proportion of HAAA in SAA was 3.3%. Most of HAAA were associated with non-A, non-B and non-C hepatitis virus. Compared with that of non-HASAA, the abnormality of T cell immunity of HAAA was more severe, with a higher frequency of early infection and a higher mortality rate.