Pneumonia in solid organ transplant recipients: a prospective multicenter study

Background: Pneumonia frequently affects solid organ transplant (SOT) recipients, with high morbidity and mortality. However, the few studies on pneumonia in this population are mainly retrospective, single-center, and long-term studies, or include patients with only one type of SOT or a specific etiology. We performed a point prevalence study to investigate epidemiology, diagnosis, therapy, and outcome of pneumonia in an unselected SOT population. Methods: Italian and Spanish transplant centers were invited to report on all SOT recipients with pneumonia treated during 2 separate weeks (1 each in February and June 2012). Results: In total, 35 centers (18 in Italy, 17 in Spain) agreed to participate and collected 54 cases. The incidence of pneumonia was 10.1 episodes/1000 recipients/year. Pneumonia was classified as late (>6 months) in 70.4% of cases. Pneumonia was also classified as community-acquired (CAP), healthcare-associated (HCAP), and hospital-acquired (HAP) pneumonia in 40.7%, 38.9%, and 20.4% of cases, respectively. An attempt to microbiological diagnosis (≥1 sample) was made in 94.4% of patients, with a diagnostic yield of 60.7%. Causative agents included bacteria (87.1%), virus (29%), and fungi (6.4%). A multidrug-resistant bacterium was isolated in 18.2%, 40%, and 100% of patients with CAP, HCAP, and HAP (P = 0.007), respectively. Overall, 11.1% of patients were admitted to the intensive care unit, 3.7% developed graft rejection, and graft function deteriorated in 18.5%. In-hospital mortality was 1.9%. Conclusion: Pneumonia remains a frequent problem in SOT recipients, although it occurs later in patients who are in better physical health. Therefore, harmful pathogens and worse outcome are less common than previously thought.