Hudson, Madeline

ABSTRACT Trimethoprim/sulfamethoxazole (TMP/SMX) prophylaxis can prevent Pneumocystis jirovecii pneumonia (PJP) and other opportunistic infections (OI). We sought to assess the frequency, causative factors, and impact of early TMP/SMX discontinuation in abdominal solid organ transplant (SOT). This is a single‐center, retrospective cohort study of abdominal SOT recipients at Mayo Clinic Arizona (MCA) between January 2021 and June 2023. Primary study goals were to determine the rate and reasons behind early TMP/SMX discontinuation and whether TMP/SMX prophylaxis was reinitiated. Secondary outcomes included mean duration of therapy, alternative prophylactic agent utilized, and incidence of TMP/SMX‐preventable OI. A total of 930 abdominal SOT recipients were included (592 kidney, 253 liver, 85 multiorgan transplants). TMP/SMX was discontinued early in 184 (20%) patients: 77 kidney, 84 liver, 23 multiorgan. Predominant reasons for discontinuation were hyperkalemia (39%) and cytopenias (35%). Median duration of TMP/SMX prophylaxis before discontinuation was 54.5 (18.0, 93.2) days. TMP/SMX was not resumed in 62% of cases (36% kidney, 89% liver, 52% multi‐organ). The predominant reason for non‐resumption was alternative prophylaxis with no clear intent to rechallenge TMP/SMX (70%). Alternative prophylaxis included pentamidine (43%), none (30%), dapsone (22%), and atovaquone (5%). Of patients reinitiated, 86% (59/69) successfully remained on TMP/SMX through the prophylaxis period. One TMP‐SMX‐preventable OI (nocardiosis) was observed in the TMP/SMX discontinuation group. TMP/SMX is often discontinued prematurely in SOT recipients without resumption despite resolution of the offending cause. TMP/SMX prophylaxis should be maintained where possible, as alternative therapy may not offer the same broad spectrum of protection against OI.

AbstractTixagevimab/cilgavimab (tix/cil) received emergency use authorization in December 2021 for pre‐exposure prophylaxis against COVID‐19 in moderately to severely immunocompromised patients. Our study aimed to describe the incidence of COVID‐19 infection and assess the immunologic risks associated with tix/cil in kidney, pancreas, liver, and heart transplant recipients. Retrospective chart review was completed to provide descriptive analysis. Outcomes data included COVID‐19 infection, severity of COVID‐19 infection, graft function, and rejection. Safety outcomes included cardiovascular (CV) and hypersensitivity events post tix/cil administration. A total of 410 transplant patients were included in the analysis: 20 heart, 92 liver, 243 kidney, 25 simultaneous pancreas/kidney, 23 simultaneous liver/kidney, and seven simultaneous heart/kidney. Twenty‐seven (6.5%) patients tested positive for COVID‐19 via PCR or antigen test post tix/cil. No apparent difference was observed in patients testing positive for COVID‐19 by type of organ transplant (p = .122). Twenty‐five of the 27 patients testing positive for COVID‐19 reported symptomatic infection, only nine of whom were hospitalized. No patients were mechanically ventilated and no deaths due to COVID‐19 occurred. No significant changes in graft function were observed. Clinically significant rejection was diagnosed and treated in four patients. COVID‐19 breakthrough infection rates remained low in immunocompromised solid organ transplant recipients who received tix/cil. No significant immunologic risks were observed.