A comparison of the pattern of interstitial pneumonitis following allogeneic bone marrow transplantation before and after the introduction of prophylactic ganciclovir therapy in 1989.

A comparison was made of the pattern of interstitial pneumonitis (IP) following allogeneic bone marrow transplantation before and after the introduction of ganciclovir prophylaxis to minimize the risk of cytomegalovirus (CMV) disease in the St Vincent's Hospital bone marrow transplant program in 1989. A total of 456 recipients of allogeneic transplants were included. 280 received no prophylactic ganciclovir while 176 received prophylactic ganciclovir. The overall incidence of interstitial pneumonitis dropped from 19.6 to 12.5% (P = 0.03) and this was primarily due to a reduction in the incidence of CMV-IP which fell from 12.9 to 1.7% (P < 0.0005). The incidence of idiopathic IP was not different between the two groups (6.3 vs 3.2%), nor was the incidence of Pneumocystis carinii pneumonia (2.9 and 0.6%). Prophylactic ganciclovir has thus had a significant impact in reducing both the overall incidence of IP and specifically cytomegalovirus IP in allogeneic marrow transplant recipients. The most common form of IP in patients given prophylactic ganciclovir is now idiopathic interstitial pneumonitis.