ABSTRACT
Lung transplantation survival rates are lower than those for other types of solid-organ transplantation. The reason is higher rates of infection and rejection-related complications. 1 , 2 Infectious complications are the leading cause of morbidity and mortality at every time point following lung transplantation and the cause of death of at least 50% of lung transplant recipients (LTRs). Bacterial infection is the most frequent infectious complication of lung transplantation and accounts for 35% to 66% of infections. Overall, 50% to 85% of LTRs experience at least one episode of bacterial infection. 3 Most of these episodes occur in the immediate posttransplant period (i.e., 2 weeks after transplantation), with more than 80% of infections occurring in the lung, mediastinum, and pleural space. 2 , 3 Although such bacterial infection creates a considerable hazard in LTRs, most patients respond to antibiotic therapy and survive. Maurer and colleagues reported that although bacterial infection (more than half of which is pneumonia) is the most common type, it results in a lower mortality rate than either viral or fungal infection does. 4 Another study of early bacterial pneumonia (i.e., occurring within 2 weeks of lung transplantation) reported an overall rate of mortality resulting from bacterial pneumonia of only 3% for the entire cohort, although 1 of11 patients with bacterial pneumonia did die. 5 In absolute numbers, however, bacterial pneumonia is responsible for the greatest number of early deaths caused by infection. 6 One autopsy study of 131 patients who received transplants between 1986 and 1995 showed that 48% of deaths after lung transplantation were caused by bacterial infections (in most cases by pneumonia). 7 Other causes of death were surgical complications (19%), posttransplant lymphoproliferative disorder (7%), and unrelated causes (7%). Rejection was not a major cause of death during the early posttransplant period or the first year after transplantation. 7 Although pneumonia is common, other serious life-threatening types of infection, such as bacteremia and urinary tract infections, also occur. Pediatric lung transplants pose a significant risk for bacteremia, which does carry significant mortality. 8
