Impact of Screening and Treatment of Ureaplasma species on Hyperammonemia Syndrome in Lung Transplant Recipients: A Single Center Experience

Abstract

Background: Infection with Ureaplasma species (spp) has been linked to fatal hyperammonemia syndrome (HS) in lung transplant recipients. We sought to characterize the epidemiology of Ureaplasma spp in candidates and donors and describe outcomes of antimicrobial therapy in preventing and treating HS.

Methods: Candidate testing for Ureaplasma spp was performed with urine culture and polymerase chain reaction (PCR) pretransplant. Positive candidates were treated with levofloxacin. Donor testing was performed with bronchoalveolar lavage (BAL) culture and PCR intraoperatively. From 7/2014 to 2/2017 patients were treated according to results; from 2/2017 to 10/2018 recipients received empiric levofloxacin and azithromycin at transplant until testing returned negative. HS was defined as new onset altered mental status after transplant with ammonia > 200 µmol/L.

Results: In total, 60 patients who underwent lung transplant were included. And 80% (n = 48) of patients had negative screening tests in donor and candidate pre-lung transplant, 8.3% (n = 5) of recipients had positive Ureaplasma spp testing in urine pre-transplant, and 13.3% (n = 8) had positive donor BAL testing at the time of lung transplant. Three patients developed HS a median of 7 days posttransplant; 2 died of HS. Recipients of organs with Ureaplasma spp who received empiric therapy did not develop HS. Donors with Ureaplasma spp were younger and more sexually active.

Conclusions: Donor-derived Ureaplasma spp in lung transplant was associated with HS. Screening lung donors for Ureaplasma spp might allow for targeted therapy to reduce risk for development of HS, but future confirmatory studies are needed.

Keywords: Ureaplasma spp; donor-derived infection; hyperammonemia syndrome; lung transplant.