632. Donor-Derived Mollicute Infections in Lung Transplant Recipients: a Prospective Study of Donor Respiratory Tract Screening and Recipient Outcomes
Authors: Tam Patrick C , Alexander Barbara D , Lee Mark J , Hardie Rochelle G , Reynolds John M , Haney John C , Waites Ken B , Baker Arthur W 
Published: December 2022

Abstract

Background
Mollicutes, such as Mycoplasma hominis and Ureaplasma spp, are fastidious bacteria that can cause invasive donor-derived infections in lung transplant recipients. Best practices for donor screening and recipient surveillance for Mollicute infections are unknown. This study assessed the performance of donor respiratory tract screening for Mollicutes.

Methods
We prospectively analyzed all lung transplant surgeries performed 10/5/20 – 9/25/21 at a single transplant center. Donor bronchoalveolar lavage (BAL) performed at time of procurement was tested for presence of urogenital Mycoplasmas and Ureaplasma spp. using culture and PCR. Treating clinicians were blinded to these results.
Post-transplant recipient evaluation was performed at the discretion of the treating clinicians, who maintained a high index of suspicion for Mollicute infection. Mollicute cases were defined as recipients with any post-transplant culture or PCR that detected a Mollicute. We analyzed recipient outcomes and assessed the performance of donor BAL screening in predicting recipient Mollicute cases.

Results
In total, 115 patients underwent lung transplant. Of this cohort, 99 (86%) donors had adequate BAL samples for Mollicute testing via both culture and PCR. 8/99 (8%) donors had culture-positive samples, and 15/99 (15%) had PCR-positive samples for Mollicutes. Among the 99 corresponding recipients, 9 (9%) patients met the Mollicute case definition (Figure 1). These recipients were diagnosed a median of 6 days after transplant (IQR 4-15 days). 6 patients had pulmonary Mollicute detection alone, and 3 had invasive extrapulmonary thoracic infections. The only death was unrelated (Table 1).
Donor BAL culture sensitivity was 6/9 (67%) in predicting recipient Mollicute cases, and sensitivity of PCR was 5/9 (56%). Positive predictive value (PPV) was 6/8 (75%) for donor culture and 5/15 (33%) for PCR (Table 2). Figure 1Clinical courses of 9 lung transplant recipients who acquired post-transplant Mycoplasma hominis or Ureaplasma species.
Table 1 Characteristics of 9 lung transplant recipients who acquired post-transplant Mycoplasma hominis or Ureaplasma species.
Table 2 Performance of donor bronchoalveolar lavage screening methods in predicting Mollicute acquisition among 99 lung transplant recipients.

Conclusion
In our single center cohort, donor BAL screening via culture predicted all serious recipient Mollicute infections and had better PPV than PCR. Given limitations of either screening method, clinicians should maintain a high index of suspicion for Mollicute infection after lung transplant to facilitate early diagnosis and effective treatment.

Disclosures
Barbara D. Alexander, MD, Astellas: Advisor/Consultant|HealthtrackRx: Advisor/Consultant|HealthtrackRx: Grant/Research Support|Scynexis: Grant/Research Support|UpToDate: Advisor/Consultant Arthur W. Baker, MD, MPH, Medincell: Advisor/Consultant.