Prediction of cytomegalovirus pneumonia after marrow transplantation from cellular characteristics and cytomegalovirus culture of bronchoalveolar lavage fluid.

Bronchoalveolar lavage (BAL) was performed between days 35 and 45 posttransplant in 37 marrow recipients without clinical or radiologic evidence of cytomegalovirus (CMV) pneumonia to determine if the presence of CMV or cellular characteristics was predictive of subsequent development of CMV pneumonia. Analysis of BAL fluid included culture and direct fluorescent antibody staining for CMV, total mononuclear cell count, lymphocyte count, and lymphocyte subsets. Patients were followed to day 110 after transplant for development of CMV pneumonia. Weekly cultures of blood, urine, and throat were also obtained. BAL was positive for CMV in 7 patients, of whom 3 developed CMV pneumonia. It was negative for CMV in 30 patients, of whom 7 developed CMV pneumonia. The positive and negative predictive values for detection of CMV in day 35-45 BAL were 43% and 78%, for CMV viremia 66% and 87%, and for detection of CMV in urine and throat 41% and 94%, respectively, for subsequent CMV pneumonia. In 9/10 patients who subsequently developed CMV pneumonia, excretion of CMV from BAL, blood, urine or throat preceded CMV pneumonia, and BAL was the earliest site of CMV excretion in all nine. Only one patient did not excrete before developing CMV pneumonia. In a stepwise logistic regression of risk factors for developing CMV pneumonia, only CMV viremia was significant (P = 0.002) although the total BAL mononuclear cell count approached significance (P = 0.053). The percentage of lymphocytes in BAL and CMV excretion in BAL, urine, and throat were not significant. The positive predictive value of BAL for subsequent CMV pneumonia was no greater than that of culture of urine and throat and less than that of viremia in our patients.