John W. Baddley

Background. Immunosuppressive conditioning regimens for chimeric antigen receptor-modified T cell immunotherapy (CARTx) and subsequent T cell dysfunction increase risk for infection. However, it is difficult to discern infection from CRS in the early (up to Day 30) and late (Days 31–180) periods after CARTx due to overlapping signs and symptoms. Methods. We analyzed infectious complications and predictors of infection during the early and late periods after CARTx in 213 adult patients with malignancies over a 5-year period. Results. Overall, 75 patients (35%) had at least one infection, mostly within the first 30 days after CARTx. Infections occurring early after CARTx were mostly bacterial, whereas viral infections predominated after Day 30. In multivariate analyses, a high baseline CRP (≥5 mg/dL) was significantly associated with increased risk of infection in the early period after CARTx, and a Day-5-to-baseline-CRP ratio of <1.5 was significantly associated with a higher risk of infection through all 180 days after CARTx and during the late period after CARTx. Conclusions. Infections in adult patients are common up to 180 days after receiving CARTx. High baseline CRP without significant temporal changes may predict risk of infection. Tracking CRP trends may be a useful clinical tool for discerning causes of fever and guiding antibiotic stewardship in this population at high risk for infections.

The epidemiology of invasive fungal infections (IFIs) among patients receiving Bruton tyrosine kinase inhibitors (BTKIs) remains incompletely characterized. We conducted a systematic review and meta-analysis of 88 studies including 23 737 patients to evaluate the prevalence and risk factors for IFIs in this population. Among 16 studies that applied the European Organization for Research and Treatment of Cancer and the Mycoses Study Group Education and Research Consortium consensus definitions of IFIs, the pooled prevalence of proven/probable IFIs was 2.83% (95% confidence interval [CI], 1.97-4.06), with the highest prevalence observed in patients with central nervous system lymphoma (9.02%). Aspergillosis was the most frequently reported IFI (1.76%), followed by pneumocystosis, candidiasis, and cryptococcosis. The risk factors significantly associated with proven/probable IFIs were concurrent corticosteroid use (odds ratio [OR], 5.03; 95% CI, 2.31-10.92) and ≥3 previous lines of therapy (OR, 3.26; 95% CI, 1.54-6.88). Across clinical trials, the prevalence of fungal infections varied across BTKI agents, ranging from 2.50% with tirabrutinib, to 0.62% with pirtobrutinib. Data on antifungal and Pneumocystis jirovecii pneumonia prophylaxis were limited and inconclusive. Among clinical trials that reported fungal infections as adverse events, the prevalence of IFI was the highest in patients treated with tirabrutinib (2.50%), followed by zanubrutinib (2.13%), ibrutinib (1.75%), acalabrutinib (1.31%), orelabrutinib (1.08%), and pirtobrutinib (0.62%). Although some findings suggest a potential benefit in selected patients, current evidence remains insufficient to support broad prophylaxis recommendations. These results underscore the need for individualized risk assessment and further research to inform prevention strategies.

Background: Kidney transplantation (KT) from donors with human immunodeficiency virus (HIV-1) to recipients with HIV (HIV D+/R+) is noninferior to KT from donors without HIV (HIV D−/R+) with regard to safety. However, there may be differences in posttransplant infections. Methods: We performed a secondary analysis of the HOPE in Action KT Study (NCT02602262) comparing the time to first clinically relevant infection within 24 months posttransplantation in 99 HIV D+/R+ versus 99 HIV D−/R+. Secondary outcomes included incidence rates, infection-related death, and timing of clinically relevant infection, each stratified by donor HIV status. Results: The cumulative incidence of a clinically relevant infection at 24 months posttransplantation was 73.8% (95% confidence interval [CI]: 63.1%–81.2%) for HIV D+/R+ versus 64.7% (95% CI: 53.0%–73.4%) for HIV D−/R+. Comparing time to first clinically relevant infection in HIV D+/R+ versus HIV D−/R+, the adjusted hazard ratio (aHR) was 1.44 (95% CI: 1.01–2.04) at 24 months posttransplantation; for infections associated with hospitalization, the aHR was not significantly higher (1.21 [95% CI: .78–1.86). There were no significant differences in the number of infections, death from infection, duration, or site of infection between HIV D+/R+ versus HIV D−/R+, though viral infections were numerically more common in HIV D+/R+ (40% vs 35%). Conclusions: Although there was a statistically significant association between receipt of a kidney from a donor with HIV and time to first clinically relevant infection in the 24 months posttransplantation, there were no differences in infections associated with hospitalization. These data are overall reassuring as this emerging practice expands into clinical care. Clinical Trials Registration. NCT02602262.

Background: Multidrug‐resistant organism colonization and infections cause significant morbidity and mortality in solid organ transplantation, affecting the perioperative antibiotic management. Yet, international practices for screening and antibiotic prophylaxis in colonized donors and recipients remain poorly defined. Methods: Self‐administered, web‐based survey conducted between February and July 2025 to assess global practices in multidrug‐resistant organism screening and perioperative antibiotic management in SOT, developed by transplant infectious diseases experts and endorsed by the Transplant Infectious Diseases Section of the Transplantation Society and the European Society of Clinical Microbiology and Infectious Diseases Study Group for Infections in Compromised Hosts. Data collected included respondent and institution characteristics; screening and prophylaxis protocols; donor and recipient colonization management; and timeframes relevant for prophylaxis modification. Results: Responses from 125 transplant centers across 24 countries and four continents were included. Most respondents were infectious disease physicians (73.6%). Antimicrobial stewardship programs and transplant infectious diseases consultation were available in 93.6% and 85.6% of centers, respectively. Over half (52.0%) modified prophylaxis based on donor multidrug‐resistant organism colonization, mainly triggered by urine and respiratory cultures. Preservation fluid and surveillance cultures influenced decisions less often. Recipient screening protocols were reported by 61.6% of centers, primarily targeting carbapenem‐resistant Enterobacterales (80.8%). About 41.6% routinely adjusted prophylaxis for colonized recipients, especially with recent (1–3 months) colonization. Conclusion: Substantial international variability exists in multidrug‐resistant organism screening and perioperative prophylaxis practices in solid organ transplantation. Evidence‐based consensus guidelines are needed to standardize and improve prevention of donor‐derived and recipient infections globally.

The recent international resurgence of measles has led to significant public health concerns and poses significant risks to immunocompromised patients, including those who have undergone solid organ transplantation (SOT). SOT recipients may present atypically and are at an increased risk of severe complications of measles infection, underscoring the importance of preventative measures. This review summarizes contemporary data regarding measles transmission, the clinical presentation, diagnosis, and treatment of SOT recipients, as well as strategies for measles prevention, infection control considerations, postexposure prophylaxis, and opportunities for the mitigation of donor‐derived measles and measles vaccine viruses.

Introduction: Pediatric Infectious Disease (PID) clinicians involved in solid organ transplantation often assess infection risk and mitigation strategies for donor organ offers. While some guidance is available, real‐life practice patterns have not been previously described. Methods: We surveyed PID clinicians about organ acceptance and associated posttransplantation interventions using 12 fictitious pediatric case scenarios through 3 PID‐specific listservs. Descriptive statistics were employed. Results: 48 (71.6%) of 67 ID respondents were involved in organ offer assessment. Agreement was strong (> 80%) to accept (syphilis, severe acute respiratory syndrome coronavirus 2 [SARS‐CoV‐2], MRSA, E. coli , TB [liver], rhino/enterovirus) or decline (undifferentiated encephalitis, TB [lung]) organs from these cases, while there was less agreement for cases with risk of coccidioidomycosis, Chagas disease, multi‐drug‐resistant Acinetobacter baumannii , and influenza. Less agreement was present for posttransplant monitoring and antimicrobial administration. Practice varied in testing and treatment for donors with SARS‐CoV‐2 positive test, MRSA bacteremia, and Chagas disease. Conclusions: For many pediatric organ offer scenarios, agreement in donor acceptance was high; however, improved education based on currently available recommendations may enhance organ acceptance decision‐making. The variability in management highlights educational and research opportunities to optimize strategies to limit the impact of donor‐derived infections in pediatric organ recipients.

As part of an ongoing series of social media discussions, the Transplant Infectious Diseases Early Career Network hosted an open forum for the transplant infectious disease community to discuss the development of research careers for junior faculty. Topics discussed included opportunities for research, identifying potential research questions, institutional support, grant funding, common barriers to research, and trainee involvement. The forum highlighted symbiotic relationships between junior faculty and trainees. The insights from the forum provide a valuable resource for early‐career transplant infectious diseases (TID) researchers.