Diana F. Florescu

Background: Norovirus (NoV) can cause chronic relapsing and remitting diarrhea in immunocompromised patients. Few multicenter studies have described the clinical course, outcomes, and complications of chronic NoV in transplant recipients.Methods: A multicenter retrospective study of adult and pediatric SOT and HSCT recipients diagnosed with NoV between November 1, 2017, and February 28, 2021. Data were obtained from electronic medical records (EMR) and entered into a central REDCap database. Descriptive statistics were calculated.Results: A total of 280 NoV+ patients were identified across eight sites. The majority were adults (74.1%) and SOT recipients (91.4%). Initial diagnosis of NoV occurred a median of 36 months post‐Tx (IQR [15.0, 90.0]). Most NoV cases had >3 diarrheal episodes daily (66.0%), nausea and vomiting (60.1%). Duration of diarrhea varied greatly (median = 10 days, mean = 85.9 days, range (1, 2100)). 71.3% were hospitalized. Adjustment of immunosuppression, including reduction and discontinuation of mToR inhibitor, CNI, and/or MMF, was the most common management intervention for NoV. Other therapies resulted only in temporary improvement. Four patients died within 30 days and three others died by 180 days postdiagnosis. Clinically significant renal dysfunction was observed in 12.5% by 30 days and 21.4% by 180 days post‐NoV diagnosis.Conclusion: In HSCT and SOT patients, NoV frequently resulted in severe symptoms, prolonged diarrhea (30% persistent with diarrhea for >30 days), and clinically significant renal dysfunction (up to 21% of patients). Utilized therapies did not reliably result in the resolution of infection demonstrating the need for more effective treatment. image

West Nile virus (WNv) is a major cause of viral encephalitis in the United States. WNv infection is usually asymptomatic or a limited febrile illness in the immunocompetent hosts, although a small percentage can develop neuroinvasive disease. Neuroinvasive disease due to WNv in solid organ transplant recipients occurs at higher rates than observed in the general population and can have long term neurological sequalae.Methods: We retrospectively reviewed medical records of all solid organ transplant recipients at our institution who tested positive for WNv from 2010 to 2018. Two reviewers performed electronic searches of Medline, Embase, Cochrane Library of literature of WNv infections in SOT. Descriptive statistics were performed on key variables.Results: Eight recipients (mean age 54, five males) were diagnosed with neuroinvasive WNv infection at our institution. Distribution of infection was as follows: five kidney transplants, one in each kidney‐pancreas, liver, and lung. Diagnoses included meningitis (3), encephalitis (1), meningo‐encephalitis (4). Median time from transplant to infection was 49.8 months (2.7–175.4). No infections were considered donor‐derived. Five patients received treatment with IVIG. Six patients were alive at median follow‐up of 49.5 months (21.7–116.8). We identified 29 studies published from 2002 to 2019. Median time from transplant to infection was 14.2 months, with similar allograft distribution; 53% were donor‐derived infections.Conclusion: WNv infections in solid organ transplant recipients can be a consequence of organ donation or can be acquired via the community. Infections can be more severe in SOT recipients and lead to neuroinvasive disease. image

Mycobacterium tuberculosiscan be transmitted via organ donation and result in severe outcomes. To better understand donor‐derived tuberculosis (DDTB), all potential transmissions reported to the Organ Procurement and Transplantation Network (OPTN) Ad Hoc Disease Transmission Advisory Committee between 2008 and 2018 were analyzed. Among 51 total reports, nine (17%) (9 donors/35 recipients) had ≥ 1 recipient with proven/probable disease transmission. Of these, eight were reported due to recipient disease, and one was reported due to a positive donor result. Proven/probable DDTB transmissions were reported in six lung and five nonlung recipients. The median time to diagnosis was 104 days posttransplant (range 0–165 days). Pulmonary TB, extrapulmonary TB, pulmonary plus extrapulmonary TB, and asymptomatic TB infection with positive interferon‐gamma release assay were present in five, three, one, and two recipients, respectively. All recipients received treatment and survived except for one whose death was not attributed to TB. All donors associated with proven/probable DDTB had ≥ 1 TB risk factor. Six were born in a TB‐endemic country, five had traveled to a TB‐endemic country, three had been incarcerated, and three had latent TB infection. These cases highlight the importance of evaluating donors for TB based on risk factors. Early posttransplant TB in organ recipients of donors with TB risk factors requires prompt reporting to OPTN to identify other potential affected recipients and implement timely treatment interventions.

Solid organ transplant recipients are at increased risk for infections due to chronic immunosuppression. Diarrhea is a commonly encountered problem post transplantation, with infectious causes of diarrhea being a frequent complication. Viral infections/enteritides in solid organ transplant recipients often result from frequently encountered pathogens in this population such as cytomegalovirus, adenovirus, and norovirus. However, several emerging viral pathogens are increasingly being recognized as more sensitive diagnostic techniques become available. Treatment is often limited to supportive care and reduction in immunosuppression, though antiviral therapies mayplay a role in the treatment in certain diseases. Viral enteritis is an important entity that contributes to morbidity and mortality in transplant recipients.

Sepsis is a complex disease stemming from a dysregulated immune response toward an infectious agent. In transplantation, sepsis remains one of the leading causes of morbidity and mortality. Solid organ transplant recipients have impaired adaptive immunity due to immunosuppression required to prevent rejection. Immunosuppression has unintended consequences, such as increasing the risk of infections and sepsis. Due to its high morbidity and mortality, early detection of sepsis is paramount to start aggressive treatment. Several biomarkers or combination of biomarkers of sepsis have emerged in the last decade, but they are not dependable for early diagnosis or for outcome prognosis.