Pulmonary infiltrates in liver transplant recipients in the intensive care unit

Background A frequent dilemma is discerning the likelihood of pneumonia and the need for empiric antibiotic therapy in liver transplant recipients with pulmonary infiltrates in the intensive care unit (ICU). Methods. We performed a prospective, observational study of consecutive liver transplant recipients developing pulmonary infiltrates in the ICU. Results. Of 90 consecutive liver transplant patients in the ICU over a 3-year period, 44% (40) developed pulmonary infiltrates. The etiologies were pneumonia (38%, 15 of 40), pulmonary edema (40%, 16 of 40), atelectasis (10%, 4 of 40), adult respiratory distress syndrome (8%, 3 of 40), contusion (3%, 1 of 40), and unknown (3%, 1 of 40). Pneumonia was due to methicillin-resistant Staphylococcus aureus in 27% (4 of 15), Pseudomonas aeruginosa (27%, 4 of 15), invasive aspergillosis (20%, 3 of 15), and Enterobacter cloacae, Serratia marcescens, Pneumocystis carinii pneumonia, and unknown (7%, 1 of 15) in one each. None of the patients had cytomegalovirus or herpes simplex virus pneumonia. Seventy-five percent of methicillin-resistant Staphylococcus aureus and all Aspergillus pneumonias, but only 14% of the Gram-negative pneumonias, occurred within 30 days of transplantation. Twenty-seven percent of the pneumonias occurred >365 days after transplantation; all of these were in patients with recurrent viral hepatitis C virus or hepatitis B virus, disseminated posttransplant lymphoproliferative disorder, or late rejection. Of patients with pneumonia, 87% were ventilated and 40% had bacteremia. Clinical pulmonary infection score (Pugin score) >6 (73% vs. 6%, P=0.0001), abnormal temperature (73% versus 28%, P=0.005), and creatinine level >1.5 mg/dl (80% versus 50%, P=0.05) were predictors of pneumonia versus other etiologies of pulmonary infiltrates. Overall mortality in patients with pulmonary infiltrates was 28% (11 of 40); pneumonia as etiology (P=0.06), creatinine level >1.5 mg/dl (P=0.028), higher blood urea nitrogen (P=0.017), and worse APACHE neurological score (P=0.04) were predictors of poor outcome. Conclusions. Our data have implications not only for identifying pneumonia as a potential cause of pulmonary infiltrates, but for the likely etiology of the pneumonia and thus the selection of empiric antibiotic therapy in critically ill liver transplant recipients. Pugin score >6 in patients with pulmonary infiltrates warrants antimicrobial therapy. Early onset within 30 days after transplantation raises the spectra of as pergillosis.