Transplant Patients: Give Them Space

Patients who undergo solid organ transplant are at increased risk of pneumocystis pneumonia, caused by Pneumocystis jirovecii, due to their compromised immune status. Antimicrobial prophylaxis is the standard of care in most transplant centers. Clinicians in Europe, Japan, Australia, and India have reported outbreaks of this severe opportunistic fungal infection in renal transplant recipients. In North America, no cases had been reported until recently.

This outbreak is described in American Journal of Infection Control in a retrospective case—control study prepared by a team from the University of Ottawa, Ontario, Canada. They observed 10 adult renal transplant recipients who developed pneumocystis pneumonia at a Canadian center, and 30 matched controls. All patients received prophylaxis with trimethoprim-sulfamethoxazole for 1 year post-transplantation.

The median time between transplantation and infection was 10.2 years. No patients died of the infection.

Patients who developed pneumocystis pneumonia had lower estimated glomerular filtration rates, averaging 29.3 mL/min compared to 66.3 mL/min in patients who did not develop pneumocystis pneumonia.

These researchers also did transmission mapping (tracking visits for medical services to determine if patients had been in the same place at the same time) since transmission of Pneumocystis jirovecii may be human-to-human.

They determined that patients who developed pneumocystis pneumonia often attended clinics and the clinical laboratory at the same time as control patients. Among the 10 infected patients, 9 had had contact with another symptomatic patient.

All pneumocystis pneumonia was tracked to the same strain of Pneumocystis jirovecii.

The researchers advise investigating all potential health care contacts where transmission could have occurred, including clinical laboratories and ambulatory clinics. In this study, they found that overlapping ambulatory care visits were potential sources of infection transmission. Taking steps to keep transplant patients out of confined spaces with other patients could interrupt transmission of respiratory pathogens.