Introduction

Solid-organ transplantation has transformed the prognosis of patients with end-stage kidney disease and other life-threatening organ failures, offering sustained improvements in survival and quality of life. However, this success is tempered by the heightened risk of infections that accompany long-term immunosuppressive therapy, surgical manipulation and the presence of indwelling devices. Post-transplant infections remain a leading cause of morbidity, graft dysfunction and mortality, underscoring the need for vigilant prevention and prompt management strategies. The spectrum of infectious complications in transplant recipients is broad, encompassing bacterial, viral, fungal and parasitic pathogens, with their incidence and severity influenced by the intensity of immunosuppression, the timing after transplantation, donor- and recipient-derived factors and local epidemiology. This article reviews the epidemiology, timing and pathogenesis of post-transplant infections, summarizes current evidence on prophylaxis and surveillance and outlines principles of early recognition and management. By integrating advances in diagnostics, pharmacology and preventive care, clinicians can minimize infectious complications, optimize graft outcomes and improve the overall survival of transplant recipients [1].

Description

Post-transplant infections represent one of the most significant threats to graft and patient survival, accounting for a substantial proportion of post-operative morbidity. The risk of infection is determined by a delicate balance between the recipientâ??s immune status, exposure to pathogens and the net state of immunosuppression. Factors such as the intensity and duration of immunosuppressive therapy, presence of central lines or urinary catheters, delayed graft function and episodes of rejection requiring augmented immunosuppression heighten susceptibility. The epidemiology of infections varies according to the time elapsed since transplantation: the first month is dominated by surgical-site infections, catheter-associated bacteremia and nosocomial pneumonia; months one to six are characterized by opportunistic pathogens such as Cytomegalovirus (CMV), Pneumocystis jirovecii and certain fungi; beyond six months, community-acquired infections predominate, though late opportunistic infections remain a risk in patients with persistent immunosuppression. Geographic and institutional differences, including endemic mycoses or tuberculosis in specific regions, also shape the infectious landscape [2].

Timely diagnosis of post-transplant infections is essential, as delayed recognition can lead to rapid deterioration, graft dysfunction, or systemic sepsis. Standard evaluations rely on a combination of clinical assessment, targeted imaging and laboratory investigations, but interpretation is often complicated by atypical presentations due to blunted inflammatory responses in immunosuppressed hosts. Periodic cultures of urine, blood and respiratory secretions are recommended in high-risk patients, particularly during periods of intensified immunosuppression. Biomarkers such as procalcitonin and galactomannan have adjunctive value in distinguishing bacterial or fungal etiologies. Effective surveillance requires integration of laboratory findings with epidemiological trends, environmental exposures and clinical suspicion to ensure prompt and appropriate intervention [3].

Prevention of post-transplant infections hinges on a multifaceted approach encompassing perioperative measures, antimicrobial prophylaxis, vaccination and patient education. Meticulous surgical technique and aseptic protocols reduce the risk of wound and catheter-related infections. Antibacterial prophylaxis, tailored to local resistance patterns, is administered perioperatively to cover skin and enteric flora. Vaccination plays a critical role: pre-transplant immunization against influenza, pneumococcus, hepatitis B and human papillomavirus is recommended, while live vaccines are generally avoided after transplantation. Patient counseling regarding hand hygiene, safe food practices and avoidance of environmental exposures such as soil or stagnant water helps reduce acquisition of opportunistic pathogens. Equally important is the judicious adjustment of immunosuppression to balance graft protection with infection risk, supported by regular monitoring of drug levels and immune function assays [4].

The management of post-transplant infections requires a multidisciplinary approach that integrates rapid pathogen identification, appropriate antimicrobial therapy and careful modulation of immunosuppression. Empiric treatment should be guided by local antibiograms, infection severity and host factors, with subsequent tailoring based on microbiological data. Therapeutic drug monitoring is vital, as interactions between antimicrobials and calcineurin or mTOR inhibitors can alter drug exposure and toxicity. For viral infections such as CMV or BK virus, antiviral therapy combined with reduction of immunosuppression is often effective, though resistant strains may necessitate alternative agents or experimental therapies. Fungal infections require prolonged therapy with agents such as echinocandins, azoles, or amphotericin B, depending on the species and site involved. Advances in immunotherapy, including adoptive transfer of pathogen-specific T cells, are under investigation for refractory viral infections. Strengthening antimicrobial stewardship, surveillance of emerging pathogens and personalized prophylactic strategies will be crucial to improving outcomes [5].

Conclusion

Post-transplant infections continue to be a major determinant of patient and graft outcomes, despite significant advances in immunosuppression, diagnostics and antimicrobial therapy. Their prevention and management demand an integrated approach that begins before transplantation and extends throughout long-term follow-up. Careful donor and recipient screening, targeted vaccination and appropriate prophylaxis lay the foundation for risk reduction, while ongoing surveillance and early use of molecular diagnostics enable timely detection of emerging pathogens. Effective treatment requires prompt initiation of empiric therapy, rapid adjustment based on microbiological data and close attention to drug interactions and the balance between antimicrobial efficacy and graft-preserving immunosuppression. Continued collaboration among transplant teams, infectious disease specialists, microbiologists and public health authorities will be essential to address evolving challenges, including antimicrobial resistance and opportunistic infections. By integrating scientific advances with patient-centered care, clinicians can optimize graft longevity, enhance survival and improve the overall quality of life for individuals living with a transplanted organ.

Acknowledgment

None.

Conflict of Interest

None.

References

1. Patel G, Rana MM, Huprikar S (2013). Multidrug-resistant bacteria in organ transplantation: An emerging threat with limited therapeutic options. Curr Infect Dis Rep 15: 504-513.

                                  Google Scholar Cross Ref Indexed at

2. Bodro M, Sabé N, Tubau F, Lladó L, Baliellas C, et al. (2013). Risk factors and outcomes of bacteremia caused by drug-resistant ESKAPE pathogens in solid-organ transplant recipients. Transplantation 96: 843-849.

                                  Google Scholar Cross Ref Indexed at

3. Ramette A, Kronenberg A. (2018). Prevalence of carbapenem-resistant Acinetobacter baumannii from 2005 to 2016 in Switzerland. BMC Infect Dis 18: 159.

                                  Google Scholar Cross Ref Indexed at

4. Pérezâ?Nadales E, Fernándezâ?Ruiz M, Gutiérrezâ?Gutiérrez B, Pascual Á, Rodríguezâ?Baño J, et al. (2022). Extendedâ?spectrum βâ?lactamaseâ?producing and carbapenemâ?resistant Enterobacterales bloodstream infection after solid organ transplantation: Recent trends in epidemiology and therapeutic approaches. Transpl Infect Dis 24: e13881.

                                  Google Scholar Cross Ref Indexed at

5. Jin M, Zeng L, Zhang W, Deng X, Li J, et al. (2021). Clinical features of multidrug-resistant organism infections in early postoperative solid organ transplantation in a single center. Ann Palliat Med 10: 4555562-4554562.

                                  Google Scholar Cross Ref Indexed at