Infections caused by Pneumocystis jirovecii (PJ), an opportunistic fungus, can have major consequences in terms of morbidity and mortality. These infections occur mainly in immunocompromised patients and are known for their pulmonary tropism (Pneumocystis pneumonia, PCP). Epidemiologically, more PJ infections are now encountered in the non-HIV (human immunodeficiency virus) population than in HIV-infected individuals. While prevention modalities have been studied in HIV-infected populations, evidence is scarce in non-HIV patients. The decision to prescribe prophylaxis for PJ requires assessment of the clinical context, as well as existing risk factors that may predispose an individual to develop PCP. Few indicators exist that are sufficiently sensitive and specific to predict the occurrence of PCP. While certain underlying conditions have clear recommendations for prophylaxis such as solid organ transplant recipients, evidence is scarce. The decision to use prophylaxis must be made while taking into consideration the overall context of the patient.

Patterns of bacterial infections and antimicrobial resistance in solid-organ transplant recipients: A five-year retrospective study

Intravesical Bacillus Calmette-Guerin (BCG) is a live attenuated vaccine for tuberculosis. Intravesical BCG (iBCG) administration is a highly effective immunotherapy for non-muscle invasive bladder cancer (NMIBC). Although live attenuated vaccines are generally contraindicated in solid organ transplant recipients (SOTR), iBCG has been utilized for NMIBC in SOTR. We describe the clinical manifestations, management, and outcomes of disseminated Mycobacterium bovis-BCG infection (Mb-BCGi) following iBCG therapy in SOTR for NMIBC. All adult patients (>18years of age) diagnosed with NMIBC who received iBCG across three tertiary referral and transplant centers between 2000 and 2025 were identified. The study cohort consisted of SOTR who had received iBCG for NMIBC and subsequently developed disseminated Mb-BCGi. English language literature review was performed to identify additional cases. A total of 4207 patients received iBCG during the study period. Thirty (0.71%) were SOTR, of whom two (6.7%) developed disseminated Mb-BCGi, including bloodstream infection and prostate abscesses. Literature review identified two additional disseminated Mb-BCGi cases in SOTR with lungs, bloodstream, and native kidney involvement, and one fatality. All cases required extended antimycobacterial therapy. Median times from SOT to Mb-BCGi and from iBCG to Mb-BCGi were 104 and 8months, respectively. SOTR appear to be at a higher risk of disseminated Mb-BCGi following iBCG. Administration of iBCG in SOTR with NMIBC warrants careful risk-benefit assessment and subsequent close monitoring.

ABSTRACT Background Live vaccination in patients with vascular anomalies (VA) receiving sirolimus remains controversial due to immunosuppressive effects and theoretical risks. Procedure This single‐center retrospective study included patients with VA less than 4 years old at the start of sirolimus therapy who were incompletely vaccinated. Immunologic evaluation during sirolimus therapy was categorized as normal, abnormal, or no/partial evaluation. Based on results, patients were encouraged to proceed with live attenuated vaccinations (varicella zoster virus [VZV]; measles–mumps–rubella [MMR]) or discussed with immunology. Vaccination outcomes were reviewed and reported descriptively. Results Among 45 eligible patients, 24 (53%) underwent complete immunologic evaluation. Thirteen of these (54%) had normal results; five of these (38%) were vaccinated while on sirolimus without complication. Eleven (46%) had abnormal evaluations; four of these (36%) were vaccinated while on sirolimus, with one developing a self‐limiting varicella‐like rash and fever. Twenty‐one patients (47%) had partial or no immunological evaluation; 10 of these (48%) proceeded with vaccination while on sirolimus without complications. Overall, 24 patients (53%) received live vaccines (19 on sirolimus, five after holding sirolimus therapy for at least 2 months), with only one experiencing a mild vaccine‐related event. No life‐threatening complications occurred. Conclusion In young patients with VA receiving sirolimus, live vaccine‐associated infection risk appears low and comparable to rates in solid organ transplant recipients on immunosuppression. Immunologic evaluation may help identify those at higher risk, though most tolerated vaccination without adverse events. Our practice prioritizes varicella vaccination first, given the availability of effective treatment for potential complications.

Patients living with human immunodeficiency virus (HIV) infection have been gradually accepted as solid organ transplant recipients, although there is still concern that the burden of immunosuppression and HIV infection could increase the risk of post-transplant cancer. The risk of de novo cancer was evaluated in a prospective cohort of 272 HIV-positive and 816 matched HIV-negative liver transplant recipients in Spain (2002-2012). All tumors, except hepatocellular carcinoma recurrence and non-melanoma skin cancer, after liver transplant were considered as events and death as competing event in this study. Despite matching, patients with HIV were significantly younger (45.8 vs 49.3 years). Sixteen (5.9%) patients with HIV and 61 (7.5%) HIV-negative patients developed de novo cancers (P = .39) after a median follow-up of 59.8 and 72.3 months, respectively. The most frequently diagnosed types of tumors were non-Hodgkin lymphoma (n = 19), lung cancer (n = 14), and head and neck cancer (n = 14). Time of onset, distribution, and tumor stage at diagnosis were similar in both groups. The cumulative incidences of de novo cancer at 5 and 10 years were, respectively, 6% and 12% in patients with HIV and 6% and 13% in uninfected patients. Survival after cancer diagnosis did not differ between groups. The only factor related to the development of de novo cancers was a higher age at transplantation. Human immunodeficiency virus infection per se is not associated to a higher risk of de novo cancer after liver transplantation.

BackgroundKetamine has demonstrated efficacy in treatment-resistant depression, primarily in psychiatric or outpatient populations. Its use in ICU patients remains underexplored, with limited data beyond case reports and small series. This study evaluated the association between subanesthetic ketamine infusions and improvement in depressive symptoms and hemodynamic changes in ICU patients.MethodsWe conducted a retrospective study of adults admitted to the ICU who received IV ketamine (0.3-0.75 mg/kg over 40 min on three consecutive days) for depressive symptoms. Changes in depressive symptoms were assessed using routine clinical documentation by physicians, nurses, and occupational and physical therapists. Hemodynamic parameters (blood pressure and heart rate) were recorded before and up to 120 min after infusion. The primary outcome was to evaluate depressive symptoms while the secondary outcome was to assess hemodynamic changes post transfusion.ResultsThirty-four patients met criteria, including 18 solid organ transplant recipients. Median age was 59 years; 61.8% were male. Ketamine was associated with improvement in apparent sadness (90.0% vs 52.2%, P < .05) and reported sadness (95.0% vs 59.1%, P < .05). In transplant recipients, improvement in apparent sadness remained significant (80.0% vs 41.7%, P < .05). Hemodynamic parameters remained stable; heart rate increased transiently at 15-30 min post-infusion, returning to baseline by 60-90 min. Adverse effects observed were anxiety (12.5%), restlessness and/or agitation (10.4%), and dissociation (8.16%).ConclusionSubanesthetic ketamine improved specific depressive symptoms in critically ill ICU patients without significant hemodynamic instability. These findings support its potential as a rapid-acting antidepressant in the ICU, warranting further prospective trials.

To define the incidence of donor-derived infection (DDI) in recipients of solid organ transplant (SOT) from donors with positive blood cultures and to assess the impact of shorter versus longer duration of targeted preemptive antibiotic therapy (PAT). Retrospective, single-center, cohort study. Mayo Clinic Arizona. Recipients transplanted between 1/1/2019 and 7/1/2024 who received an organ from a donor with positive blood cultures. The primary outcome was incidence of DDI. Secondary outcomes included duration of PAT and incidence of donor blood culture contamination. Among 199 SOT recipients from 167 unique donors with positive blood cultures, two recipients developed confirmed DDI within 30 days of SOT. Both cases were gram negative bacillary bacteremia not treated in donors and occurred immediately posttransplant prior to adequate recipient PAT. Six-month graft survival and recipient survival were 96.5% and 97.5% respectively. 139 recipients (69.8%) received PAT for a median duration of 7 days. There was no difference in rate of infections between recipients provided with ≤7 days versus 8-14 days of PAT for donor blood cultures; however, recipients who received 8-14 days had more Clostridioides difficile infections (CDIs) within 60 days of SOT (7.7% vs 1.5% ≤ 7 days, P = .040) and were more often discharged on intravenous antibiotics (32.3% vs 11.3%, P < .001). We observed a low rate of DDI following receipt of organs from donors with positive blood cultures. DDI occurred in cases without adequate donor/recipient treatment. Longer durations of targeted PAT resulted in more CDI and intravenous antibiotics on discharge.

Robotic Abdominal Wall Reconstruction in Transplant Patients: A Single Institution Case Series.

Background/Objectives: Tuberculosis remains one of the preventable causes of mortality among liver transplant recipients. The prevalence of tuberculosis in solid organ transplant recipients is higher than in the general population. The aim of this study was to evaluate the incidence of latent tuberculosis infection (LTBI) and active tuberculosis after liver transplantation. Methods: This is a retrospective, single-center, case-control study. Adult liver transplant candidates who were evaluated between 1 January 2016 and 31 December 2022 were retrospectively assessed. Patients with pre-transplant tuberculin skin test (TST) and/or interferon-gamma release assay (IGRA) results who underwent transplantation were included in this study. Results: A total of 111 liver transplant recipients with available IGRA and/or TST results were included; 70 were men (63.1%) and 41 were women (36.9%), with a mean age of 53.5 ± 11.3 years. Demographic, clinical, and laboratory characteristics were evaluated. The most common indication for liver transplantation was viral hepatitis (33.3%), followed by cryptogenic cirrhosis (19.8%) and hepatocellular carcinoma (10.8%). All patients had a Bacillus Calmette-Guérin (BCG) vaccination scar. Ten patients received grafts from deceased donors, while 101 underwent living-donor liver transplantation. No patient received LTBI treatment before transplantation, whereas LTBI treatment was initiated in four patients after transplantation. None of the patients had a diagnosis of active tuberculosis prior to transplantation. Thoracic computed tomography revealed findings compatible with tuberculosis sequelae in 11 patients (9.9%). During a median follow-up period of 49 [27-64] months after transplantation, no cases of active tuberculosis were observed among patients with positive TST and/or IGRA results. Patients were divided into two groups according to their TST and IGRA results. Group 1 consisted of patients with IGRA positivity and/or a TST ≥ 5 mm, while Group 2 included patients with a TST < 5 mm and negative IGRA results. The only statistically significant difference between the groups was the administration of LTBI treatment (p = 0.027); four patients in Group 1 received LTBI therapy. None of these patients were able to continue prophylaxis due to treatment-related adverse effects. Conclusions: Prophylaxis with hepatotoxic agents poses a substantial risk in liver transplant candidates. Since the hepatotoxicity may cause early cessation of LTBI treatment, the risk-benefit ratio of post-transplant LTBI therapy should be carefully assessed. In situations where LTBI treatment is deferred, close clinical monitoring is strongly recommended.

Chagas disease (CD), a neglected tropical disease usually associated with Latin America, is increasingly recognized as an emerging infection in the United States. Screening for CD is recommended for solid organ transplant (SOT) candidates with epidemiologic risk factors; however, data on prevalence and post-transplant reactivation in the United States remain limited. We conducted a retrospective cohort study of SOT candidates and recipients screened for T. cruzi at a large transplant center in Miami, Florida. Demographics, clinical characteristics, and 2-year outcomes of recipients with CD were analyzed. Between August 1, 2013, and August 1, 2023, 6021 SOTs were performed. 1898 candidates (31%) were screened, and 21 (1.1%) tested positive for T. cruzi, of whom 10 were SOT recipients. All seropositive recipients were born in historically endemic areas. Median post-transplant surveillance was 13.5 (range 1-25) months. Seven patients developed Chagas disease reactivation (CDR) diagnosed by serum PCR; all were asymptomatic. Median time from transplantation to reactivation was 48days (range 22-426). Treatment with benznidazole for 60days cleared the parasitemia in all patients. At 2years, 80% (8/10) had graft survival, one patient died unrelated to CDR. We report a high incidence of CDR among SOT recipients at a US transplant center serving a predominantly immigrant population, with favorable 2-year outcomes. Most reactivation events occurred early post-transplant, although a later recurrence was also observed. Intensive monitoring for CDR proved effective in detecting reactivation prior to the onset of symptoms.

The awareness regarding hepatitis E virus (HEV) infection in solid organ transplant (SOT) had increased within the last decades after the reports of chronicity and associated complications. The aim of this study was to describe HEV outcome over a long period in a large cohort of SOT patients. This retrospective, single-center study analyzed 6452 SOT patients followed between 2001 and 2024 and systematically screened for HEV in cases of elevated liver enzymes. Since 2016, SOT patients were also screened for HEV at 3- and 12-months post-transplantation. We assessed the incidence, natural history, treatment, and extrahepatic manifestations. HEV infection was diagnosed in 228 patients (3.53%). The incidence was significantly higher in liver-transplant patients compared to others. At 3 months post-HEV documentation, 65.1% developed chronic hepatitis, while 34.9% achieved spontaneous viral clearance. Tacrolimus use was independently associated with chronicity, while mycophenolic acid use was protective. Ribavirin was the main antiviral therapy, achieving a 91.5% sustained virological response rate when treatment was extended until complete serum and stool HEV RNA clearance. A minority of patients required multiple treatment courses or failed therapy, with some developing cirrhosis or dying viremic. Three patients died from decompensate HEV-related cirrhosis. HEV-associated neurological manifestations (2.2%) and glomerular diseases (3.9%) were observed, often resolving with viral clearance. HEV infection is frequent in SOT recipients, with significant risks of chronicity and extrahepatic complications. Ribavirin remains the cornerstone of treatment, and individualized duration improves outcomes. Screening for HEV is mandatory in SOT patients with elevated liver enzymes.

Solid organ transplantation (SOT) has significantly increased over the past few decades, with more than 170,000 SOTs performed worldwide in 2023. Although immunosuppressive treatments have improved patient survival, they have also increased the risk of infections among SOT recipients (SOTRs), especially pneumonia. Pneumonia remains one of the leading causes of morbidity and mortality, with respiratory infections contributing to 30 to 70% of deaths in SOTRs, depending on the organ transplanted and the timing of infection. This review summarizes current knowledge on the epidemiology, risk factors, microbial etiology, and clinical manifestations of pneumonia in SOTRs. Temporal patterns of infection are also explored, with early posttransplant infections frequently caused by nosocomial or donor-derived pathogens, and community-acquired infections predominating beyond 6 to 12 months posttransplantation. The lack of robust, SOT-specific guidelines for pneumonia complicates the management of this entity in SOTRs. Most recommendations are based on extrapolations from immunocompetent populations. Furthermore, the lack of large, prospective trials comparing empirical antibiotic strategies in SOTRs limits evidence-based decision-making. Despite these challenges, early initiation of empirical therapy remains crucial to improving outcomes. The review highlights the importance of timely microbiological diagnosis, individualized antimicrobial stewardship, and targeted therapeutic approaches in the context of increasing antimicrobial resistance. Incorporating local epidemiological data and patient-specific risk profiles may enhance the accuracy of diagnosis and support the de-escalation of therapy upon pathogen identification.

ObjectiveHead/neck location and immunosuppression are independent risk factors related to cutaneous head and neck squamous cell carcinomas (cHNSCCs) in solid organ transplant recipients (SOTRs). Traditional staging criteria underperform in risk stratification. We aim to identify the utility of clinicopathologic factors for risk stratification of cHNSCCs in SOTRs.Study DesignRetrospective cohort study.SettingSingle tertiary center.MethodsSOTRs with surgically resected cHNSCCs between 2009 and 2019 were reviewed. Deeply invasive cHNSCCs extended deep to the subcutis. Data were extracted from electronic records. Overall survival was analyzed by level of invasion and transplant type using Mantel‐Cox test and by age at transplant and age at first posttransplant cHNSCC using univariate Cox regression. Level of invasion was evaluated using unpaired t‐tests for age at transplant, age at first posttransplant cHNSCC, and overall lifespan; ANOVA for transplant type; and chi‐square test for sex and ethnicity.ResultsOf 77 identified patients, 44 (100% White, 97.7% non‐Hispanic, 81.8% male) met criteria. Sixteen developed deep invasion. Deep invasion correlated with decreased overall survival (P = .0021) and shorter overall lifespan (P = .02). Age at first cHNSCC (HR = 1.00, 95% CI = 0.96‐1.04), age at transplant (HR = 1.02, 95% CI = 0.98‐1.07), and transplant type (P = .83) were unrelated to overall survival. Age at transplant approached significance (P = .07) for deep invasion. There was no difference in level of invasion by sex (P = .12), ethnicity (P = .18), or transplant type (P = .21).ConclusionDeeply invasive cHNSCCs are associated with decreased overall survival in SOTRs. Age at transplant approaches significance for deep invasion. Data on immunosuppression and genetic analysis may further enhance prognostication.

The Prevalence and Consequences of Supra-Normal Estimated Glomerular Filtration Rate in Pediatric Solid Organ Transplants: A Single Center Cohort.

Immunocompromised patients include those with innate T or B cell suppression, acquired immunodeficiency states such as those caused by human immunodeficiency virus infection, and those with medication-induced immunosuppression (chemotherapy or immunotherapy, solid organ transplant recipients). Any of these entities can place patients at increased risk of severe respiratory infection. We propose an algorithmic approach to the diagnosis of pulmonary complications that can arise in the immunocompromised patient. The first step is to gather all relevant clinical data to understand the history leading up to presentation, as well as the specific underlying immunosuppressive state. Following this, the clinician must identify the predominant imaging pattern of disease to help narrow the differential diagnosis and guide clinical management. Third, the time course of the clinical and imaging findings should be classified as acute, subacute, or chronic. We define the distinction between acute/subacute and chronic disorders as before or after 12 weeks. At the conclusion of these steps, it is hoped that a tailored differential diagnosis will allow for a rapid and precise management plan of these challenging patients.

Solid organ transplant recipients are at increased risk of developing head and neck squamous cell carcinoma (HNSCC). These patients often require free flap reconstruction; however, data on outcomes in this immunosuppressed population remain limited and formal management guidelines are lacking. We conducted a systematic review and pooled proportions meta-analysis, and a retrospective institutional database review, to compare outcomes of head and neck free flap reconstruction in transplant versus non-transplant patients. Cancer-related mortality and time from surgery to death were also assessed. The systematic review yielded four eligible studies. Kidney transplantation and anterolateral thigh flaps were the most common. Prednisone was the predominant immunosuppressant. The pooled flap success rate was 97%, with recipient and donor site complication rates of 21% and 16%, respectively. Our database had 14 transplant patients who underwent head and neck reconstruction for oral SCC (n = 12) or osteoradionecrosis (n = 2). Tacrolimus was the most common immunosuppressant. Recipient/donor site dehiscence, skin graft loss, and reoperation were significantly higher in transplant patients. Rates of infection, salivary leak, hardware exposure, or hematoma were similar. Overall mortality was significantly higher in transplant patients (64% vs. 23%; p < 0.001), although the 2-year mortality did not differ on Kaplan-Meier analysis. Although free flap survival in transplant patients is comparable to non-transplant patients, postoperative complication rates are higher. Given their distinct risk profile and poorer prognosis, transplant patients with HNSCC may benefit from dedicated treatment guidelines.

WCN26-4881 MANAGEMENT OF NOROVIRUS INFECTION IN SOLID ORGAN TRANSPLANT RECIPIENTS: A SCOPING REVIEW

Effectiveness, immunogenicity and safety of human papillomavirus vaccination in non-HIV immunocompromised individuals: a systematic review.

Tirzepatide in solid organ transplant recipients: Early real-world signals of efficacy and safety-A narrative review.

The risk factors for donor-acquired (DA) CMV transmission in CMV-seronegative pediatric solid organ transplant (SOT) recipients (R-) receiving organs from CMV-seropositive donors (D+) remain unknown in the era of routine antiviral prophylaxis. DA-CMV transmission was defined as CMV antigenemia/DNAemia and/or seroconversion in a D+/R- recipient by 13 months post-transplant. DA-CMV transmission, along with donor and recipient demographics, was studied in a retrospective cohort of CMV D+/R- children who had a SOT at the Stollery Children's Hospital from 2000 to 2018. All patients were expected to receive at least 3 months of CMV-active antiviral prophylaxis. 105 CMV D+/R- pediatric SOT recipients (48 liver, 35 heart, 4 lung, 18 kidney) were analyzed; DA-CMV transmission occurred in 58 patients (55%). Frequency of DA-CMV transmission was highest in lung (75%), followed by liver (69%), then kidney (61%), and was lowest in heart recipients (31%). Median time to DA-CMV transmission was 4.8 months (3.4-6.7). In a multivariable cox regression model including organ, donor and recipient age and sex, risk of DA-CMV transmission was significantly lower in heart versus liver recipients (HR 0.30, 95% CI 0.14, 0.65, p = 0.003). Understanding factors that result in non-transmission of CMV to seronegative recipients despite receiving a seropositive organ may guide more targeted use of antiviral prophylaxis in pediatric SOT recipients.