Beam, Elena

Abstract Background Mycoplasma hominis, Ureaplasma urealyticum, and Ureaplasma parvum may cause post-transplant infections in lung transplant recipients. We evaluated routine pretransplant screening for these Mollicutes. Methods We retrospectively reviewed records of lung transplant recipients at our tri-site institution from 01/01/2015 to 11/15/2019. M. hominis and/or Ureaplasma polymerase chain reaction (PCR) was performed on pretransplant recipient urine specimens and donor bronchial swabs at the time of transplantation. Development of Mollicute infection and hyperammonemia syndrome (HS) was recorded. Results A total of 268 patients underwent lung transplantation during the study period, of whom 105 were screened with at least 1 Mollicute PCR. Twelve (11%) screened positive; 10 donors, 1 recipient, and 1 both. Among positive donors, 3 were positive for M. hominis, 5 for U. urealyticum, and 4 for U. parvum. Preemptive therapy included doxycycline, levofloxacin, and/or azithromycin administered for 1–12 weeks. Despite therapy, 1 case of M. hominis mediastinitis and 1 case of HS associated with Ureaplasma infection occurred, both donor-derived. Of those screened before transplant, cases with positive screening were more likely (P < 0.05) to develop Mollicute infection despite treatment (2/12, 17%) than those who screened negative (1/93, 1%). Conclusions Pretransplant recipient urine screening had a low yield and was not correlated with post-transplant Mollicute infection, likely because most M. hominis and U. parvum/urealyticum infections in lung transplant recipients are donor-derived. Routine donor bronchus swab PCR for M. hominis, U. urealyticum, and U. parvum followed by preemptive therapy did not obviously impact the overall incidence of Mollicute infection or HS in this cohort.

Abstract Background Solid organ transplant recipients (SOTRs) are at high‐risk for severe infection from severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2). Anti‐spike monoclonal antibodies are currently utilized under emergency use authorization to prevent hospitalization in high‐risk individuals with coronavirus disease 2019 (COVID‐19), including SOTRs. However, clinical data for bebtelovimab, the sole currently available anti‐spike monoclonal antibody for COVID‐19, is limited. Methods We conducted a retrospective cohort study of adult SOTRs diagnosed with mild‐to‐moderate COVID‐19 from January 2022 through May 2022 who received either bebtelovimab or sotrovimab. The primary outcome was COVID‐19‐related hospitalization within 30 days of COVID‐19 diagnosis. Data were analyzed with Fisher's exact test. Results Among 361 SOTRs, 92 (25.5%) received bebtelovimab and 269 (74.5%) received sotrovimab. The most common organ transplant was a kidney (42.4%). SOTRs who received bebtelovimab had a higher proportion who had received a booster SARS‐CoV‐2 vaccine dose and had received their last vaccination dose more recently. Eleven (3.0%) SOTRs were hospitalized, and rates of hospitalization were similar between monoclonal antibody groups (3.3% versus 3.0%; p > .99). Three patients required admission to an intensive care unit, all of who received sotrovimab. Four (1.1%) patients died within 30 days of COVID‐19 diagnosis, two from each group. Conclusions SOTRs with mild‐to‐moderate COVID‐19 who received bebtelovimab had similar rates of COVID‐19‐related hospitalization as those who received sotrovimab. While differences in vaccination rates and viral subvariants could act as confounders, bebtelovimab appears to be of similar effectiveness as sotrovimab. image

Abstract Tixagevimab-cilgavimab is authorized for preexposure prophylaxis against coronavirus disease 2019 (COVID-19) in immunocompromised hosts. Herein, we report the clinical characteristics of 8 patients who developed COVID-19 soon after receiving tixagevimab-cilgavimab. This study emphasizes the need to maintain additional measures to prevent COVID-19 during periods of high severe acute respiratory syndrome coronavirus 2 transmission.

AbstractGraft‐versus‐hostdisease (GVHD) following liver transplantation (LT) is rare but can lead tosignificant mortality. The leading cause of death following GVHD diagnosis isinfectious complications. However, there is a lack of clear descriptions concerning infection and antimicrobial management patterns. Our study aims toprovide the focused details of all infectious complications of acute GVHDfollowing LT. We retrospectively reviewed all adult LT recipients with acute GVHD at Mayo Clinic's Transplant Centers from January 1, 2010, to December 31, 2021. Detailed characteristics of infection in each case were described. Among 4,585 LTs performed during this period, 12 (0.3%) patients developed acuteGVHD. The median time from transplantation to GVHD diagnosis was 49.0 days [IQR 31.5–99.0]. Ten (83.3%) patients developed severe infections leading tomortality. The most common cause of infection was nosocomial bacteremia fromenteric bacteria such as vancomycin‐resistant enterococci and gram‐negative bacilli. Other infections included breakthrough invasive fungal infections,cytomegalovirus (CMV) reactivation, and Clostridioides difficile colitis. Antimicrobial prophylaxis strategies in most cases were based on the degree of neutropenia—these include levofloxacin for bacterial prophylaxis, nebulized pentamidine for Pneumocystis jiroveci pneumonia prophylaxis, posaconazole for invasive fungal prophylaxis, and valganciclovir based on CMVstatus. All GVHD patients with severe infections succumbed to thesecomplications. Ourstudy reiterates that despite prophylaxis, infectious complications in GVHDfollowing LT are common and lead to exceptionally high mortality. Individualizedantimicrobial treatment, prophylaxis and monitoring strategies remain a criticalcomponent of GVHD management. Further study to optimize these practices isrequired. image

Abstract Background Corynebacterium periprosthetic joint infection (PJI) is a poorly described infectious syndrome. Prior studies included cases of polymicrobial infections. This series describes the clinical characteristics, management, and outcomes of monomicrobial Corynebacterium PJI. Methods We queried the Mayo Clinic Total Joint Registry for cases of monomicrobial Corynebacterium knee and hip PJI in adults (age ≥18 years) between 2010 and 2019. Results A total of 20 (1%) out of 2067 PJI cases met our inclusion criteria. Most were males (55%), and the median age was 64 years. Seventy percent had chronic symptoms (>4 weeks). PJI was delayed to late (>3 months postimplantation) in 90%. Three species were identified: C. striatum (70%), C. jeikeium (20%), and C. amycolatum (10%). All tested isolates were susceptible to vancomycin (100%) and linezolid (100%), and most had a minimum inhibitory concentration ≤0.06 mcg/mL to daptomycin (75%). Other agents were less reliable, with high resistance to oral agents commonly used for suppression. Nineteen patients were treated: 37% debridement and implant retention (DAIR), 47% 2-stage exchange, and 16% resection without reimplantation. Of these, failure occurred in 29%, 11%, and 0%, respectively. Conclusions Corynebacterium PJIs pose a therapeutic challenge due to limited antimicrobial armamentarium and undefined optimal surgical intervention. Vancomycin and linezolid remain the most reliable agents for treatment. DAIR may be attempted for acute PJI, but verification of durable chronic suppression options will be critical for this approach.

AbstractBackgroundImmunocompromised individuals are at risk for Nocardia infection, with a recurrence rate of approximately 5%. Solid organ transplant (SOT) recipients often receive secondary prophylaxis due to their requirement of lifelong immunosuppression. However, data supporting this practice is sparse. We sought to evaluate Nocardia recurrence in SOT recipients, specifically evaluating secondary prophylaxis.MethodsWe conducted a retrospective cohort study of SOT recipients diagnosed with nocardiosis from 2000 through 2020. We included adult SOT recipients who completed their course of Nocardia therapy and had at least 6 months of posttherapy follow‐up. The primary outcome was Nocardia recurrence, which included relapse and reinfection.ResultsOne hundred two patients met inclusion criteria. Sixty‐six (64.7%) were male and mean age was 58.6 ± 11.7 years. Most common SOT types were kidney (46.1%), heart (18.6%), kidney‐pancreas (11.8%), and lung (10.8%). Most common sites of infection were lung (85.3%), skin (17.6%), and brain (14.7%). Secondary prophylaxis was utilized in 53 (52.0%) patients. Trimethoprim‐sulfamethoxazole (TMP‐SMX) single‐strength daily was the most common prophylaxis agent and dose. Five patients (4.9%) experienced Nocardia recurrence, three of which were receiving secondary prophylaxis at time of recurrence. Two recurrences were with the same Nocardia species. Factors associated with recurrence were lung transplantation (p = .011), chronic lung disease (p = .032), and treatment ≤120 days (p = .006). Time from treatment completion to recurrence ranged from 107 to 875 days.ConclusionsNocardia recurrence in SOT recipients is an uncommon event. TMP‐SMX secondary prophylaxis is incompletely protective and recurrence may be dependent upon other factors. Further study of secondary prophylaxis is warranted.

Abstract Background Invasive fungal infection (IFI) in heart transplant recipients is associated with poor outcomes. Estimated risk of 1‐year IFI in heart transplant recipients is 3.4–8.6% with risk factors inconsistently identified in previous studies. The role of antifungal prophylaxis is unclear. The transplant program at Mayo Clinic provides 6 months of universal azole prophylaxis for those heart transplant recipients in Arizona. We sought to define risk factors for 1‐year IFI and determine the effect of antifungal prophylaxis. Methods We conducted a retrospective cohort study of patients undergoing heart transplantation at Mayo Clinic from January 2000 to March 2019. We analyzed demographics, details of transplant hospitalization, antifungal prophylaxis, and fungal infection. Multivariable Cox analyses were performed to identify risk factors of 1‐year IFI and impact of IFI on posttransplant mortality. Results A total of 966 heart transplant recipients were identified with a median age of 56 years (IQR 47, 62). A total of 444 patients received antifungal prophylaxis. Over 1‐year follow‐up, 62 patients developed IFI with a cumulative incidence of 6.4%. In multivariable analysis, factors associated with IFI were renal replacement therapy (RRT) (HR 3.24, 95% CI 1.65–6.39), allograft rejection (HR 2.33, 95% CI 1.25–4.34), and antifungal prophylaxis (HR 0.32, 95% CI 0.11–0.96). RRT was also associated with invasive mold infection (HR 3.00, 95% CI 1.29–6.97). Conclusions RRT and allograft rejection after transplantation are associated with 1‐year IFI, and RRT is also associated with invasive mold infection. Antifungal prophylaxis appears to be protective and further study is needed in the heart transplant population.

AbstractBackgroundBamlanivimab and casirivimab-imdevimab are authorized for emergency use treatment of mild to moderate coronavirus disease 2019 (COVID-19) in patients at high risk for developing severe disease or hospitalization. Their safety and efficacy have not been specifically evaluated in solid organ transplant recipients.MethodsWe retrospectively reviewed solid organ transplant recipients who received monoclonal antibody infusion for COVID-19 at Mayo Clinic sites through January 23, 2021. Outcomes included emergency department visit, hospitalization, mortality, and allograft rejection.ResultsSeventy-three patients were treated, most commonly with bamlanivimab (75.3%). The median age was 59 years, 63% were male, and the median Charlson comorbidity index was 5. Transplant type included 41 kidney (56.2%), 13 liver (17.8%), 11 heart (15.1%), 4 kidney-pancreas (5.5%), 2 lung (2.7%), 1 heart-liver, and 1 pancreas. Eleven (15.1%) patients had an emergency department visit within 28 days of infusion, including 9 (12.3%) who were hospitalized for a median of 4 days. One patient required intensive care unit admission for a nonrespiratory complication. No patients required mechanical ventilation, died, or experienced rejection. Ten adverse events occurred, with 1 seeking medical evaluation. Hypertension was associated with hospital admission (P < .05), while other baseline characteristics were similar. The median time from symptom onset to antibody administration was 4 days in nonhospitalized patients compared with 6 days among hospitalized patients (P < .05).ConclusionsMonoclonal antibody treatment has favorable outcomes with minimal adverse effects in solid organ transplant recipients with mild to moderate COVID-19. Earlier administration of monoclonal antibody therapy appears to be more efficacious.

AbstractCytomegalovirus (CMV) pneumonia causes major morbidity and mortality. Its diagnosis requires demonstration of viral cytopathic changes in tissue, entailing risks of lung biopsy. This study aimed to determine CMV viral load (VL) thresholds in bronchoalveolar lavage fluid (BALF) for diagnosis of CMV pneumonia in immunocompromised patients. CMV VL in BALF was studied in 17 patients (83% transplant recipients) and 21 control subjects with and without CMV pneumonia, respectively, using an FDA‐approved PCR assay (Cobas® AmpliPrep/Cobas TaqMan® CMV Test, Roche Molecular Systems, Inc.) calibrated to the WHO International Standard for CMV DNA (NIBSC: 09/162). Receiver operating characteristic curve analysis produced a BALF CMV VL threshold of 34 800, IU/mL with 91.7% sensitivity and 100.0% specificity for diagnosis of possible, probable, and proven CMV pneumonia in transplant patients, while a threshold of 656 000 IU/mL yielded 100% sensitivity and specificity among biopsy‐proven cases. For all immunocompromised patients, a VL threshold of 274 IU/mL was selected. VL thresholds also were normalized to BALF cell count yielding a threshold of 0.32 IU/106 cells with 91.7% sensitivity and 90.5% specificity for possible, probable, and proven CMV pneumonia in transplant recipients. Monitoring CMV VL in BALF may be a less invasive method for diagnosing CMV pneumonia in immunocompromised patients.