Urinary tract infections are one of the main complications in kidney transplant patients, with a significant impact on graft function and survival. In fact, it is estimated that up to 74% of kidney transplant patients experience at least one episode of UTIs in the first year after transplantation, with an increased risk of graft loss and an increased risk of mortality. Several risk factors have been identified, such as female gender, old age, diabetes mellitus, immunosuppression, pre-transplant UTIs, urinary tract abnormalities, and prolonged dialysis. The worsening burden of antimicrobial resistance is also in itself a risk factor and a major complication in evolution and management. The management of prophylaxis, asymptomatic bacteriuria, and UTIs is still an open challenge, with some points to be clarified. Faced with such scenarios, our review aimed to evaluate the current epidemiology, examine the risk factors, and consider all the possibilities and methods of management, giving a current view and evaluation of the topic.

Urinary tract infections are one of the main complications in kidney transplant patients, with a significant impact on graft function and survival. In fact, it is estimated that up to 74% of kidney transplant patients experience at least one episode of UTIs in the first year after transplantation, with an increased risk of graft loss and an increased risk of mortality. Several risk factors have been identified, such as female gender, old age, diabetes mellitus, immunosuppression, pre-transplant UTIs, urinary tract abnormalities and prolonged dialysis. The worsening burden of antimicrobial resistance is also in itself a risk factor and a major complication in evolution and management. The management of prophylaxis, asymptomatic bacteriuria, UTIs and UTIs are still an open challenge with some points to be clarified. Faced with such scenarios, our review aimed to evaluate the current epidemiology, to examine the risk factors and to consider all the possibilities and methods of management, giving a current view and evaluation of the topic.

Background: Very few cases of Pneumocystis jirovecii pneumonia (PJP) have been reported in COVID-19 so far, and mostly in patients with concomitant HIV infection or in solid-organ transplant recipients. Despite COVID-19 being associated with lymphopenia and the use of steroids, there are no studies specifically aimed at investigating the risk factors for PJP in COVID-19. Methods: A retrospective case-control study was performed. We matched PJP cases with controls with a 1:2 ratio, based on age ± 10 years, solid-organ transplantation (SOT), hematological malignancies, and in the setting of PJP development (ICU vs. non-ICU). A direct immunofluorescence assay on bronchoalveolar lavage fluid was used to diagnose PJP. Results: We enrolled 54 patients. Among 18 cases of PJP, 16 were diagnosed as “proven”. Seven of the eighteen cases were immunocompromised, while the other patients had no previous immunological impairment. Patients with PJP had significantly lower median lymphocyte values (p = 0.033), longer COVID-19 duration (p = 0.014), a higher dose of steroid received (p = 0.026), higher CRP values (p = 0.005), and a lower SARS-CoV-2 vaccination rate than the controls (p = 0.029). Cumulative steroid dose is the independent risk factor for PJP development (OR = 1.004, 95%CI = 1–1.008, p = 0.042). Conclusions: PJP develops in COVID-19 patients regardless of immunosuppressive conditions and the severity of disease, and it is correlated to the corticosteroid dose received.

The rising prevalence of MDR pathogens has a significant impact on the recipients' outcome, as this increases the risk of graft complications and makes the management of the peri-transplant phase more difficult. Among the different MDR germs, Methicillin-resistant Staphylococcus aureus (MRSA) represents one of the most frequently isolated pathogens. We report for the first time the off-label use of Ceftaroline in six kidney transplant recipients with donor peritransplantation MRSA bacteremia at the Division of Kidney Transplant Unit of Federico II University Hospital of Naples, Italy, between September and December 2022. Each patient was followed up for the next three months after transplantation, monitoring the clinical and laboratory outcome, the risk of infection, and the efficacy and safety profile of the treatment performed. In the subsequent three months of follow-up to the transplant, none of the six patients showed donor-related infections. In particular, none of the six patients showed MRSA bacteremia or other related MRSA infections. In conclusion, our real-life experience shows that Ceftaroline could represent a valid therapeutic option in the management of solid organ transplant patients with a risk of donor-derived MRSA infection. However, despite the few cases considered, this approach deserves further investigation in ad hoc studies or clinical trials due to our positive results.

Pre-exposure prophylaxis for COVID-19 with Tixagevimab/Cilgavimab in immunocompromised patients has reduced the risk of breakthrough infection, disease, hospitalization, and COVID-19 related mortality. However, the advent of the Kraken variant (XBB.1.5) has limited the use of this monoclonal antibody, based on poor efficacy in in vitro studies The objective of the study was to evaluate the risk of breakthrough infection, symptomatic disease, hospitalization, intensive care admission and COVID-19 related death in kidney transplanted recipients receiving pre-exposure prophylaxis with Tixagevimab/Cilgavimab for COVID-19 in the era of the Kraken variant (XBB.1.5). In a prospective, observational study, we enrolled kidney transplant patients undergoing pre-exposure prophylaxis for COVID-19 with Tixagevimab/Cilgavimab at the Division of Infectious Diseases of Federico II University of Naples between February 2023 and August 2023. Each patient subsequently underwent a six-month follow-up with symptom monitoring and surveillance nasopharyngeal swab for SARS-CoV-2 RNA detection every 30 days, regardless of symptoms. Thirty-four kidney transplant patients were enrolled and in the follow-up period, only one tested positive for the nasopharyngeal swab for SARS-CoV-2 research with asymptomatic infection and virological recovery on the eighth day from the diagnosis of infection. Therefore, no patient developed disease and no patient needed hospitalization and no death occurred. No adverse drug reaction to Tixagevimab/Cilgavimab occurred. Our data, although derived from a limited and uncontrolled sample, show the potential of Tixagevimab/Cilgavimab as a valid and viable therapeutic strategy in pre-exposure prophylaxis for immunocompromised patients. These findings highlight the importance of conducting clinical studies on this topic.

Background: Refractory cytomegalovirus (CMV) infection remains a major challenge after solid organ transplantation (SOT) and hematopoietic stem cell transplantation (HSCT). Maribavir has demonstrated efficacy and a favorable safety profile in clinical trials, but real-world data on virological endpoints, treatment duration, and recurrence remain limited. Methods: We retrospectively reviewed all consecutive transplant recipients treated with maribavir for refractory CMV infection/disease at a tertiary referral center in Naples, Italy. Clinical and laboratory information were extracted from medical records. Results: Six patients were included: five SOT recipients and one autologous HSCT recipient. Maribavir was administered at 400 mg twice daily for a median of 43.5 days (IQR 23–56 days). At the end of treatment, five patients had detectable CMV DNA < 1000 IU/mL without confirmed clearance. Patient 6 was the only patient to achieve confirmed clearance (<LLOQ on two consecutive tests) and experienced virological and clinical rebound 18 days after discontinuation. Overall, 3/6 patients rebounded within 15–21 days. Adverse events were mild, and no patient discontinued therapy because of toxicity. Conclusions: In this small real-world series, maribavir was well tolerated and was associated with marked reductions in CMV DNA. However, three patients experienced early post-treatment rebound, including the only patient who achieved confirmed clearance. These observations are hypothesis-generating and do not establish a stopping threshold for low-level DNAemia or a validated post-treatment monitoring interval. Larger studies incorporating longitudinal viral kinetics, immune recovery, and resistance testing are needed.