Serum adenosine deaminase activity in women with hyperemesis gravidarum

BACKGROUND: Serum adenosine deaminase (ADA) activity increases in diseases where cellular immunity is stimulated. Since hyperemesis gravidarum is characterized by enhanced cell-mediated immunity, serum ADA activity may be altered. The present study evaluated the relation between serum ADA activity and changes in cell-mediated immunity as causes of changes in ADA activity in hyperemesis gravidarum. METHODS: Serum activities of total ADA and its isoenzymes, ADA1 and ADA2, were measured in women with hyperemesis gravidarum (n = 24) and normal pregnancies (n = 24). Peripheral blood lymphocyte and monocyte counts were also measured. RESULTS: In hyperemesis gravidarum, serum total ADA and ADA2 activities averaged 16.8 +/- 0.5 and 13.3 +/- 0.7 U/l, respectively, which were significantly higher than those in normal pregnancies (10.2 +/- 0.5 and 7.8 +/- 0.5 U/l, respectively) (p < 0.05). The mean values for ADA1 activity in women with hyperemesis gravidarum and normal pregnancies were similar. The increase in total ADA activity was accompanied by the increase in lymphocyte and monocyte counts. CONCLUSIONS: These results suggest that increased serum total ADA activity reflects increases in ADA2 activity, which may be at least in part attributed to enhanced cell-mediated immunity in hyperemesis gravidarum.