Prognostic value of cyclic GMP in patients undergoing allogeneic bone marrow transplantation after conditioning with total body irradiation

This study was performed to investigate whether measurement of cyclic GMP (cGMP), a marker for nitric oxide production, before and after allogeneic bone marrow transplantation (BMT) with total body irradiation (TBI) conditioning was of prognostic value. cGMP levels were monitored in 23 consecutive patients who received TBI as conditioning for BMT, and were compared with the outcome. cGMP became positive during the aplastic phase after BMT in 12 patients. In nine of these 12 patients, cGMP level decreased during the recovery phase. Eight of the nine patients survived, one dying after relapse. In three other patients, the cGMP level continued to increase even during the recovery phase and they died of severe complications. cGMP became positive on day 0 of BMT and during the leukocyte recovery phase after BMT in two and seven of the 23 patients, respectively. Subsequently, all patients died of severe complications. The two patients who were negative for cGMP both before and after BMT survived without complications. These results suggest that monitoring cGMP from early after BMT may be useful for predicting outcome and that it may be a useful prognostic marker.