Successful Liver Transplantation in a Patient With Acute COVID-19 Infection and Acute Liver Failure: A Case Report.

Current liver transplantation societies recommend recipients with active coronavirus disease 2019 (COVID-19) be deferred from transplantation for at least 2 wks, have symptom resolution and at least 1 negative severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) test.1 This approach does not address patients who require urgent transplantation and will otherwise die from liver failure. We report a successful orthotopic liver transplant (OLT) in a patient with active COVID-19 infection. This is only the second to be reported worldwide and the first in Canada.

Transplantation of a Liver Allograft From a Hepatitis C Virus Seropositive Donor With Previous Sustained Virologic Response to an Uninfected Recipient Suffering Steroid Refractory Acute Graft Rejection With No Evidence of HCV Transmission.

BACKGROUND: The goal of treating chronic hepatitis C virus (HCV) infection is sustained virologic response (SVR). There is concern that despite achieving SVR, replication-competent HCV may be sequestered at low levels within the liver and could theoretically reactivate with immunosuppression. We report transplantation of a HCV-seropositive liver donor, who achieved SVR, into a seronegative patient without HCV reactivation despite profound immunosuppression. METHOD: Retrospective chart review. RESULTS: We present a 21-year-old male who was HCV seronegative and received a liver transplant from a donor who had been treated for HCV and achieved SVR. The liver recipient, despite developing severe acute graft rejection and undergoing intense immunosuppression with T cell-depleting antibodies, did not become HCV RNA-positive with a follow up period of 8 months. The recipient was HCV seronegative before transplant, but became HCV seropositive immediately posttransplant. The antibodies were undetectable after 97 days, in keeping with a passive antibody transmission or B lymphocyte transmission with the graft. CONCLUSIONS: To the best of our knowledge, this is the first reported case of an HCV seropositive liver allograft transplanted into an HCV-negative recipient who subsequently received intense immunosuppression. This case, therefore, is an encouraging and novel step in liver transplantation, and demonstrates that SVR may be closer to a true "cure" of HCV in the donor population and that, even in circumstances of very potent immunosuppression in the recipient, this SVR is sustained.

An Exception to the Rule or a Rule for the Exception? The Potential of Using HIV-Positive Donors in Canada.

Selected human immunodeficiency virus (HIV)-infected patients with end organ failure can safely receive an organ transplant from an HIV uninfected donor. Recent demonstration of the short term safety of organ transplantation between HIV-infected persons prompted a change in US American law to allow such transplantations. Prompted by the recent completion of the first organ transplantation between HIV-infected persons in Canada, we review Canadian law regarding the use of organs from HIV-infected donors, estimate the number of potential HIV-infected donors in Canada, and critically review considerations related to advancing organ transplantation from HIV-infected donors in Canada. Existing legislation allows organ transplantation from an HIV-infected donor under exceptional medical circumstances and therefore no change in legislation is required to increase utilization of organs from HIV-infected donors for transplantation in Canada. Among 335,793 hospital deaths between 2005 and 2009 in Canadian provinces excluding Quebec, 39 potential HIV-infected donors were identified. The actual number of HIV potential donors is estimated to be approximately 60% lower (3-5 potential donor per year), if the absence of viremia is required for transplantation. Although offering all Canadians the opportunity to donate organs is a laudable goal, further research to understand the need for HIV-positive donors and the willingness of HIV-positive recipients to accept organs from HIV-positive donors is needed to inform future policy regarding organ donation from HIV-infected persons in Canada.

Clinical Pharmacokinetic Monitoring of Leflunomide in Renal Transplant Recipients with BK Virus Reactivation: A Review of the Literature.

Leflunomide is an immunosuppressive drug with in vitro and initial observational evidence of antiviral activity against BK virus (BKV), a pathogen that causes opportunistic infection upon reactivation in renal transplant recipients. Leflunomide is considered an ancillary option to immunosuppression reduction in the management of BKV reactivation. Plasma or blood concentrations of teriflunomide, the active metabolite of leflunomide, are commonly monitored because of high leflunomide doses being used, known inter-individual variability in pharmacokinetics, and hepatotoxicity risk. However, the utility of clinical pharmacokinetic monitoring for leflunomide is as yet unclear. A literature search of MEDLINE (1946-December 2016), EMBASE (1974-December 2016), the CENTRAL database, and Google Scholar was performed to identify relevant English-language articles. Further articles were identified from references in relevant literature. A previously published 9-step decision-making algorithm was used to assess the available literature and determine the utility of clinical pharmacokinetic monitoring for leflunomide. Teriflunomide is readily measurable in the plasma or blood, but a clear relationship between concentration and efficacy or toxicity is lacking, and its therapeutic range is not well-established. Efficacy and toxicity endpoints such as renal function and BKV clearance can be readily assessed without measuring teriflunomide concentrations. Pharmacokinetic parameters are affected by genetic polymorphisms in cytochrome P450 CYP2C19 and ABCG2 genes. Therefore, routine clinical pharmacokinetic monitoring of leflunomide cannot be recommended based on current available evidence. However, it may provide clinical benefit in difficult situations when patients demonstrate a lack of therapeutic response or exhibit signs of drug toxicity.

Strategies to prevent BK virus infection in kidney transplant recipients.

PURPOSE OF REVIEW: Despite improvements in posttransplant care, BK virus (BKV) remains one of the most challenging posttransplant infections in kidney transplant recipients with high rates of allograft failure. In the absence of well tolerated and efficacious viral specific therapeutics, treatment is primarily focused on reduction of immunosuppression, which poses a risk of rejection and fails to lead to viral clearance in a number of patients. RECENT FINDINGS: Recent work has turned toward preventive therapies analogous to those used for other infections like cytomegalovirus. These efforts have focused on the use of quinolone antibiotic prophylaxis to prevent BKV infection and pretransplant vaccination to boost humoral and cellular immunity. SUMMARY: Despite promising in-vitro and observational data, quinolone antibiotic prophylaxis has not been effective in preventing BKV infection in prospective studies. However, prophylaxis with newer less toxic viral specific agents such as brincidofovir - the lipid oral formulation of cidofovir - may yet prove effective. Strategies focused on eliciting a humoral immune response to recombinant virus-like particles or using adoptive transfer of BKV-specific T cells have also shown significant potential to prevent BKV infection in organ transplant recipients.

Fecal microbiota transplantation for the intestinal decolonization of extensively antimicrobial-resistant opportunistic pathogens: a review.

Treatment options for multidrug-resistant (MDR) bacterial infections are limited and often less effective. Non-pharmacologic approaches to preventing or treating MDR infections are currently restricted to improved antimicrobial stewardship and infection control practices. Fecal microbiota transplantation (FMT), a highly effective treatment for recurrent Clostridium difficile infection, has emerged as a promising therapy for intestinal MDR bacterial decolonization. A total of eight case reports have been published showing FMT resulted in intestinal decolonization of extended spectrum ß-lactamase (ESBL)-producing and carbapenemase-producing Enterobacteriaceae, vancomycin-resistant Enterococci, or methicillin-resistant Staphylococcus aureus. The procedure has been shown to work even in immunocompromised patients and those experiencing medical crises without any adverse events. Five trials are currently underway to further investigate the use of FMT for MDR bacterial decolonization. FMT is a completely novel way to eradicate drug-resistant bacteria from the intestinal reservoir and should be further investigated to address the global problem of difficult-to-treat, MDR bacterial infections.

Successful long-term management of invasive cerebral fungal infection following liver transplantation.

Central nervous system (CNS) infections after liver transplantation may be fungal in aetiology, with involvement from either common organisms such as Cryptococcus neoformans and Aspergillus spp. as well as less common organisms, such as the Mucorales and Scedosporium spp. Although the mortality of CNS fungal infections was nearly 100% in early series, more recent data has suggested that good outcomes can be achieved. This may be due to both improved diagnostic capabilities, such as the ability to obtain fungal susceptibilities and therapeutic drug levels, and improved therapeutic options, such as the newer triazoles- voriconazole and posaconazole. Due to improved outcomes, issues have now arisen around the long-term tolerability of these agents. The following two cases of invasive cerebral fungal infections following liver transplantation, one with Aspergillus flavus, and the other with Scedosporium boydii/apiospermum highlight the success that can be seen with the modern management of a previously fatal diagnosis. In particular, we highlight the issues around therapeutic monitoring and discontinuation of therapy.

Central nervous system syndromes in solid organ transplant recipients.

Solid organ transplant recipients have a high incidence of central nervous system (CNS) complications, including both focal and diffuse neurologic deficits. In the immunocompromised host, the initial clinical evaluation must focus on both life-threatening CNS infections and vascular or anatomic lesions. The clinical signs and symptoms of CNS processes are modified by the immunosuppression required to prevent graft rejection. In this population, these etiologies often coexist with drug toxicities and metabolic abnormalities that complicate the development of a specific approach to clinical management. This review assesses the multiple risk factors for CNS processes in solid organ transplant recipients and establishes a timeline to assist in the evaluation and management of these complex patients.

The impact of infection on population health: results of the Ontario burden of infectious diseases study.

BACKGROUND: Evidence-based priority setting is increasingly important for rationally distributing scarce health resources and for guiding future health research. We sought to quantify the contribution of a wide range of infectious diseases to the overall infectious disease burden in a high-income setting. METHODOLOGY/PRINCIPAL FINDINGS: We used health-adjusted life years (HALYs), a composite measure comprising premature mortality and reduced functioning due to disease, to estimate the burden of 51 infectious diseases and associated syndromes in Ontario using 2005-2007 data. Deaths were estimated from vital statistics data and disease incidence was estimated from reportable disease, healthcare utilization, and cancer registry data, supplemented by local modeling studies and national and international epidemiologic studies. The 51 infectious agents and associated syndromes accounted for 729 lost HALYs, 44.2 deaths, and 58,987 incident cases per 100,000 population annually. The most burdensome infectious agents were: hepatitis C virus, Streptococcus pneumoniae, Escherichia coli, human papillomavirus, hepatitis B virus, human immunodeficiency virus, Staphylococcus aureus, influenza virus, Clostridium difficile, and rhinovirus. The top five, ten, and 20 pathogens accounted for 46%, 67%, and 75% of the total infectious disease burden, respectively. Marked sex-specific differences in disease burden were observed for some pathogens. The main limitations of this study were the exclusion of certain infectious diseases due to data availability issues, not considering the impact of co-infections and co-morbidity, and the inability to assess the burden of milder infections that do not result in healthcare utilization. CONCLUSIONS/SIGNIFICANCE: Infectious diseases continue to cause a substantial health burden in high-income settings such as Ontario. Most of this burden is attributable to a relatively small number of infectious agents, for which many effective interventions have been previously identified. Therefore, these findings should be used to guide public health policy, planning, and research.

The risk of hypotension following co-prescription of macrolide antibiotics and calcium-channel blockers.

BACKGROUND: The macrolide antibiotics clarithromycin and erythromycin may potentiate calcium-channel blockers by inhibiting cytochrome P450 isoenzyme 3A4. However, this potential drug interaction is widely underappreciated and its clinical consequences have not been well characterized. We explored the risk of hypotension or shock requiring hospital admission following the simultaneous use of calcium-channel blockers and macrolide antibiotics. METHODS: We conducted a population-based, nested, case-crossover study involving people aged 66 years and older who had been prescribed a calcium-channel blocker between Apr. 1, 1994, and Mar. 31, 2009. Of these patients, we included those who had been admitted to hospital for the treatment of hypotension or shock. For each antibiotic, we estimated the risk of hypotension or shock associated with the use of a calcium blocker using a pair-matched analytic approach to contrast each patient's exposure to each macrolide antibiotic (erythromycin, clarithromycin or azithromycin) in a seven-day risk interval immediately before admission to hospital and in a seven-day control interval one month earlier. RESULTS: Of the 7100 patients admitted to hospital because of hypotension while receiving a calcium-channel blocker, 176 had been prescribed a macrolide antibiotic during either the risk or control intervals. Erythromycin (the strongest inhibitor of cytochrome P450 3A4) was most strongly associated with hypotension (odds ratio [OR] 5.8, 95% confidence interval [CI] 2.3-15.0), followed by clarithromycin (OR 3.7, 95% CI 2.3-6.1). Azithromycin, which does not inhibit cytochrome P450 3A4, was not associated with an increased risk of hypotension (OR 1.5, 95% CI 0.8-2.8). We found similar results in a stratified analysis of patients who received only dihydropyridine calcium-channel blockers. INTERPRETATION: In older patients receiving a calcium-channel blocker, use of erythromycin or clarithromycin was associated with an increased risk of hypotension or shock requiring admission to hospital. Preferential use of azithromycin should be considered when a macrolide antibiotic is required for patients already receiving a calcium-channel blocker.