Efficacy of antimicrobials in preventing resistance in solid organ transplant recipients:A systematic review of clinical trials

BACKGROUND In the absence of effective antimicrobials,transplant surgery is not viable,and antirejection immunosuppressants cannot be administered,as resistant infections compromise the life-saving goal of organ transplantation.AIM To evaluate the efficacy of antimicrobials in preventing resistance in solid organ transplant recipients.METHODS A systematic review was conducted using a search methodology consistent with the preferred reporting items for systematic reviews and meta-analyses.This review included randomized clinical trials that evaluated the efficacy of antimicrobial agents(prophylactic or therapeutic)aimed at preventing antimicrobial resistance.The search strategy involved analyzing multiple databases,including PubMed/MEDLINE,Web of Science,Embase,Scopus,and SciELO,as well as examining gray literature sources on Google Scholar.A comprehensive electronic database search was conducted from the databases’inception until May 2024,with no language restrictions.RESULTS After the final phase of the eligibility assessment,this systematic review ultimate-ly included 7 articles.A total of 2318 patients were studied.The most studied microorganisms were cytomegalovirus,although vancomycinresistant enterococci,Clostridioides difficile,and multidrug-resistant Enterobacterales were also analyzed.The antimicrobials used in the interventions were mainly maribavir,valganciclovir,gancic-lovir,and colistin-neomycin.Of concern,all clinical trials showed significant proportions of resistant microorga-nisms after the interventions,with no statistically significant differences between the groups(mean resistance 13.47%vs 14.39%),except for two studies that demonstrated greater efficacy of maribavir and valganciclovir(mean resistance 22.2%vs 41.1%in the control group;P<0.05).The total reported deaths in three clinical trials were 75,and there were 24 graft rejections in two studies.CONCLUSION All clinical trials reported significant proportions of antimicrobial-resistant microorganisms following interventions.More high-quality randomized clinical trials are needed to corroborate these results.

Safety and immunogenicity of COVID-19 vaccination in immunocompromised patients

The coronavirus disease 2019(COVID-19)pandemic poses a great threat to public health.Individuals who are immunocompromised because of the progression of the primary disease or receiving immunosuppressive medications are prone to severe COVID-19 complications and poor outcomes.Abundant data have shown that many COVID-19 vaccines are safe and effective in large-scale populations;however,these clinical trials have excluded immunocompromised populations.Available evidence indicates that immunocompromised populations have a blunted immune response to other vaccines,raising concerns regarding the efficacy of COVID-19 vaccination in these populations.Thus,there is an urgent need to delineate the efficacy of COVID-19 vaccines in these vulnerable populations.Here,we review the characteristics of specific humoral and cellular responses to COVID-19 vaccination in immunocompromised populations,including HIV-infected patients and those receiving immunosuppressive treatment,especially solid organ transplant recipients and those undergoing anti-CD20 treatment.We also addressed the challenges that immunocompromised populations will face in the future pandemic and the need for basic and clinical translational studies to highlight the best vaccination strategies for these populations.