Heart transplantation from COVID-positive donors with 6-month follow-up: A case series.

BACKGROUND: Data on long term outcomes in heart transplant recipients from Coronavirus disease 2019 (COVID-19) positive donors are limited. METHODS AND RESULTS: We present a series of nine patients who underwent heart transplants from COVID-19 PCR-positive donors between November 2021 to August 2022 with mean follow-up of 12.12 ± 3 months. All the recipients received two doses of COVID-19 vaccine and had at least 6 months follow-up. Eight recipients had acceptable long-term outcomes; one patient died during index admission from primary graft dysfunction. Details regarding donor and recipient characteristics, management and outcomes are provided. Two patients developed deep vein thrombosis, and one patient underwent pacemaker implantation for sinus node dysfunction. Among the surviving eight patients, none developed COVID-19 infection during follow-up period. There was no significant difference in outcome parameters when compared to patients who received hearts from donors who tested negative for COVID-19 during the same time period at our center. CONCLUSION: Keeping in mind the significant waitlist mortality in patients awaiting heart transplantation, COVID-19-positive donors should be considered for heart transplantation to help expand the donor pool and potentially reduce waitlist mortality.

Pharmacologic Management of Mycobacterium chimaera Infections: A Primer for Clinicians.

Mycobacterium chimaera, a member of the Mycobacterium avium complex, can cause infections in individuals after open heart surgery due to contaminated heater-cooler units. The diagnosis can be challenging, as the incubation period can be quite variable, and symptoms are nonspecific. In addition to aggressive surgical management, combination pharmacologic therapy is the cornerstone of therapy, which should consist of a macrolide, a rifamycin, ethambutol, and amikacin. Multiple second-line agents may be utilized in the setting of intolerances or toxicities. In vitro susceptibility of these agents is similar to activity against other species in the Mycobacterium avium complex. Drug-drug interactions are frequently encountered, as many individuals have chronic medical comorbidities and are prescribed medications that interact with the first-line agents used to treat M. chimaera. Recognition of these drug-drug interactions and appropriate management are essential for optimizing treatment outcomes.

Donor-derived Ehrlichiosis: 2 Clusters Following Solid Organ Transplantation.

Ehrlichiosis has been infrequently described as transmissible through organ transplantation. Two donor-derived clusters of ehrlichiosis are described here. During the summer of 2020, 2 cases of ehrlichiosis were reported to the Organ Procurement and Transplantation Network (OPTN) and the Centers for Disease Control and Prevention (CDC) for investigation. Additional transplant centers were contacted to investigate similar illness in other recipients and samples were sent to the CDC. Two kidney recipients from a common donor developed fatal ehrlichiosis-induced hemophagocytic lymphocytic histiocytosis. Two kidney recipients and a liver recipient from another common donor developed ehrlichiosis. All 3 were successfully treated. Clinicians should consider donor-derived ehrlichiosis when evaluating recipients with fever early after transplantation after more common causes are ruled out, especially if the donor has epidemiological risk factors for infection. Suspected cases should be reported to the organ procurement organization and the OPTN for further investigation by public health authorities.

Human parvovirus B19 in solid organ transplantation: Guidelines from the American society of transplantation infectious diseases community of practice.

Clinical manifestations of human parvovirus B19 infection can vary widely and may be atypical in solid organ transplant (SOT) recipients. However, disease is apparent when there is destruction of erythrocyte progenitor cells leading to severe acute or chronic anemia with lack of an appropriate reticulocyte response in the setting of active parvovirus B19 infection. Serology may not reliably establish the diagnosis. High-level viremia is more likely to be associated with symptomatic disease. Conversely, ongoing DNAemia after infection may not be clinically significant, if detected at low levels. Despite lack of robust data, intravenous immunoglobulin (IVIG) is frequently used for the treatment of SOT recipients with symptomatic parvovirus B19 infection. Although the optimal dosage and duration of IVIG is not known, most patients receive a total of 2 g/kg over a period of 2-5 days. A daily dose of 1 g/kg or more seems to be associated with higher incidence of toxicity. Application of standard and droplet isolation precautions remains the cornerstone for preventing human parvovirus B19 transmission. Additional research is needed to assess the efficacy of current and novel therapies and to develop a safe and effective parvovirus B19 vaccine.

Unique characteristics of cryptococcosis identified after death in patients with liver cirrhosis: comparison with concurrent cohort diagnosed antemortem.

Characteristics of cirrhosis-associated cryptococcosis first diagnosed after death are not fully known. In a multicenter study, data generated as standard of care was systematically collected in 113 consecutive patients with cirrhosis and cryptococcosis followed for 80 patient-years. The diagnosis of cryptococcosis was first established after death in 15.9% (18/113) of the patients. Compared to cases diagnosed while alive, these patients had higher MELD score (33 vs. 22, P = .029) and higher rate of cryptococcemia (75.0% vs. 41.9%, P = .027). Cases diagnosed after death, in comparison to those diagnosed during life were more likely to present with shock (OR 3.42, 95% CI 1.18-9.90, P = .023), require mechanical ventilation at admission (OR 8.5, 95% CI 2.74-26.38, P = .001), less likely to undergo testing for serum cryptococcal antigen (OR 0.07, 95% CI 0.02-0.21, P < .001) and have positive antigen when the test was performed (OR 0.07, 95% CI 0.01-0.60, P = .016). In a subset of cirrhotic patients with advanced liver disease cryptococcosis was first recognized after death. These patients had the characteristics of presenting with fulminant fungemia, were less likely to have positive serum cryptococcal antigen and posed a diagnostic challenge for care providers.

Compartmentalized Histoplasma capsulatum Infection of the Central Nervous System.

Background. Histoplasmosis is a common fungal infection in the southeastern, mid-Atlantic, and central states; however, its presentation can be atypical. Case Presentation. We report a case of Histoplasma capsulatum infection presenting as slowly progressive weakness in the lower extremities, followed by the development of numbness below the midthoracic area, urinary incontinence, and slurred speech. Brain MRI showed leptomeningeal enhancement, predominantly linear, involving the basal cisterns, the brainstem, and spinal cord. Cerebrospinal fluid analysis showed lymphocytic pleocytosis. Discussion. CNS histoplasmosis is usually seen in patients with disseminated histoplasmosis. Isolated CNS histoplasmosis is rarely seen, especially in immunocompetent patients. Conclusions. Histoplasmosis should be considered in the differential diagnosis of patients experiencing slowly progressive neurological deficit.

Cryptococcosis in Patients With Cirrhosis of the Liver and Posttransplant Outcomes.

BACKGROUND: The outcomes and optimal management of cirrhotic patients who develop cryptococcosis before transplantation are not fully known. METHODS: We conducted a multicenter study involving consecutive patients with cirrhosis and cryptococcosis between January 2000 and March 2014. Data collected were generated as standard of care. RESULTS: In all, 112 patients were followed until death or up to 9 years. Disseminated disease and fungemia were present in 76.8% (86/112) and 90-day mortality was 57.1% (64/112). Of the 39 patients listed for transplant, 20.5% (8) underwent liver transplantation, including 2 with active but unrecognized disease before transplantation. Median duration of pretransplant antifungal therapy and posttransplant therapy was 43 days (interquartile range, 8-130 days) and 272 days (interquartile range, 180-630 days), respectively. Transplantation was associated with lower mortality (P = 0.002). None of the transplant recipients developed disease progression during the median follow-up of 3.5 years with a survival rate of 87.5%. CONCLUSIONS: Cryptococcosis in patients with cirrhosis has grave prognosis. Our findings suggest that transplantation after recent cryptococcal disease may not be a categorical exclusion and may be cautiously undertaken in liver transplant candidates who are otherwise deemed clinically stable.

Incidence and clinical predictors of ocular candidiasis in patients with Candida fungemia.

Purpose. The aim of this study is to determine the incidence and the predictors of ocular candidiasis among patient with Candida fungemia. Methods. We retrospectively reviewed the charts of all patients diagnosed with candidemia at the University of Kansas Medical Center during February 2000-March 2010. Data regarding patients' demographics, clinical characteristics, laboratory results, and ophthalmology examination findings were collected. Results. A total of 283 patients with candidemia were enrolled. The mean age (± standard deviation) was 55 ± 18 years; 66% were male. The most commonly isolated Candida species were C. albicans (54%), C. parapsilosis (20%), C. glabrata (13%), and C. tropicalis (8%). Only 144 (51%) patients were evaluated by ophthalmology; however, the proportion of patients who were formally evaluated by an ophthalmologist increased during the study period (9%in 2000 up to 73%in 2010; P < 0.0001). Evidence of ocular candidiasis was present in 18 (12.5%) patients. Visual symptoms were reported by 5 of 18 (28%) patients. In multivariable analysis, no predictors of ocular candidiasis were identified. Conclusions. The incidence of ocular candidiasis among patients with fungemia remains elevated. Most patients are asymptomatic and therefore all patients with candidemia should undergo fundoscopic examination to rule out ocular involvement.

Inflammatory response following neutrophil recovery postchemotherapy in acute myeloid leukemia cases without evidence of infection: role of homing of neutrophils.

Neutropenic sepsis is a common clinical entity occurring in postchemotherapy patients. Infection may not be the cause of fever in such patients after neutrophil-count recovery. Herein, we present two patients who developed fever during the neutropenic phase of induction chemotherapy and were treated with broad-spectrum antibiotics until they were no longer febrile and had recovered their neutrophil count. Being off antibiotics, they redeveloped fever within 48-72 hours. These fevers seemed to be secondary to postinfectious inflammatory response and not infection, supported by the fact that adequate antibiotic treatment was given and the collected fluid contained neutrophils but the cultures were negative. We hypothesize an explanation for this phenomenon based on the "homing of neutrophils" to bone marrow, which involves chemoattraction of CXC chemokine receptor (CXCR)-4 expressed on neutrophils towards the chemokine stromal cell-derived factor (SDF)-1 (CXCL12) expressed constitutively by bone marrow. Literature has shown that elevation of SDF-1 levels at injured/inflamed sites might create a similar gradient. This gradient results in the migration of neutrophils to the sites of previous injury/inflammation, leading to the formation of sterile abscesses. Based on our cases, we also conclude that antibiotics do not prevent the formation or treat such sterile "abscesses"; however, the drainage of these "abscesses" and treatment with anti-inflammatory agents are useful in such cases.

Osteomyelitis: review of pathophysiology, diagnostic modalities and therapeutic options.

Osteomyelitis can affect every bone and is heterogeneous in its pathophysiology and presentation. When the diagnosis is clinically suspected, further studies such as serum inflammatory markers and imaging studies should be performed. Magnetic resonance imaging can be very useful in establishing the diagnosis and determining the extent of infection. When possible, bone specimens should be obtained and cultured prior to the initiation of antimicrobial therapy. Surgical debridement is often required for chronic or contiguous osteomyelitis for successful eradication of the infection. The ultimate test-of-cure is the lack of clinical relapse after the discontinuation of antimicrobials.

Chromosomally integrated human herpesvirus-6 in kidney transplant recipients.

BACKGROUND: During primary infection, human herpesvirus-6 (HHV-6) may become integrated into the chromosome. This entity, termed chromosomally integrated HHV-6 (CIHHV-6), is often mistaken as active infection and treated unnecessarily. The prevalence of CIHHV-6 in kidney transplant recipients is not known. METHODS: We performed quantitative HHV-6 polymerase chain reaction assay on whole blood samples collected from 47 kidney recipients. CIHHV-6 was defined as HHV-6 DNA levels >1 × 10(6) genomes/mL. RESULTS: One of 47 kidney recipients was found to have CIHHV-6. The prevalence of CIHHV-6 was calculated at 2.1% (95% confidence interval, <0.01-12.1%). Despite an increase in HHV-6 DNA level after transplant, the patient did not develop clinical HHV-6 disease. CONCLUSIONS: CIHHV-6 may be observed in kidney transplant recipients. Clinicians should be aware of this entity so as not to provide unnecessary treatment to asymptomatic patients with CIHHV-6.

New developments in the management of cytomegalovirus infection after solid organ transplantation.

Despite remarkable advances in the diagnostic and therapeutic modalities for its management, cytomegalovirus (CMV) remains one of the most important pathogens impacting on the outcome of transplantation. Not only does CMV directly cause morbidity and occasional mortality, it also influences many short-term and long-term indirect effects that collectively contribute to reduced allograft and patient survival. Prevention of CMV infection and disease is therefore key in ensuring the successful outcome of solid organ transplantation (SOT). In this regard, antiviral prophylaxis and pre-emptive therapy are similarly effective in preventing CMV disease after transplantation. However, current guidelines prefer antiviral prophylaxis over pre-emptive therapy in preventing CMV disease in high-risk SOT recipients, such as CMV-seronegative recipients of organs from CMV-seropositive donors (CMV D+/R-), and lung, intestinal and pancreas transplant recipients. Antiviral prophylaxis has the benefits of reducing not only the incidence of CMV disease, but also the indirect effects of CMV on allograft and patient survival. The major drawback of antiviral prophylaxis is delayed-onset CMV disease, which occurs in 15-38% of CMV D+/R- SOT recipients who received 3 months of prophylaxis. Allograft rejection, over-immunosuppression and lack of CMV-specific immunity are factors that predispose patients to delayed-onset CMV disease. A recent randomized trial in CMV D+/R- kidney recipients demonstrates a significant reduction in the incidence of CMV disease when valganciclovir prophylaxis is extended to 200 days (compared with the standard 100 days) after transplantation; however, the safety and cost of this prolonged approach has yet to be assessed. In some studies, delayed-onset CMV disease has been significantly associated with allograft loss and mortality. In the vast majority of patients, CMV disease responds to treatment with intravenous ganciclovir. Recently, oral valganciclovir was demonstrated to have an efficacy that is comparable to intravenous ganciclovir in treating mild to moderate cases of CMV disease in SOT recipients. Reduction in the degree of immunosuppression should complement antiviral treatment of CMV disease. Although it remains rare, ganciclovir-resistant CMV disease is increasingly seen in clinical practice, potentially fostered by the prolonged use of antivirals in high-risk over-immunosuppressed transplant recipients. Treatment of drug-resistant CMV is currently non-standardized and may include foscarnet, cidofovir, CMV hyperimmune globulins or leflunomide. The investigational drug marivabir had the potential to treat ganciclovir-resistant CMV disease as it acts through a different mechanism. However, the recent phase III clinical trial in allogeneic bone marrow transplant recipients showed that maribavir was not significantly better than placebo for the prevention of CMV disease. Similarly, the preliminary data in a liver transplant population suggests that maribavir was inferior to oral ganciclovir for the prevention of CMV disease. This article reviews the recent data and other developments in the management of CMV infection after SOT.

R753Q single-nucleotide polymorphism impairs toll-like receptor 2 recognition of hepatitis C virus core and nonstructural 3 proteins.

BACKGROUND: Hepatitis C virus (HCV) core and nonstructural (NS) 3 proteins induce inflammation and immunity through a toll-like receptor (TLR) 2-dependent pathway. Individuals with the R753Q single-nucleotide polymorphism (SNP) in the TLR2 gene have increased the risk of allograft failure after liver transplantation for chronic hepatitis C. METHODS: To test the hypothesis that R753Q SNP impairs TLR2 recognition of HCV proteins, a series of in vitro experiments were performed wherein stable clones of wild-type TLR2-deficient human embryonic kidney (HEK) 293 cells and HEK293 cells transfected with wild-type (HEK293-TLR2) or variant TLR2 genes (HEK293-TLR2-R753Q) were stimulated with HCV core and NS3 proteins. Cellular activation was assessed by nuclear factor-kappa B-driven luciferase activity, cytokine secretion, and gene upregulation. RESULTS: Compared with TLR2-deficient HEK293 cells, HEK293-TLR2 cells had marked nuclear factor-kappa B-driven luciferase activity, had modest to marked upregulation in TLR2 signaling-associated genes, and secreted large quantities of interleukin-8 during exposure to HCV core and NS3 proteins. In contrast, HEK293-TLR2-R753Q cells did not respond to stimulation with HCV and behaved similarly like TLR2-deficient HEK293 cells. CONCLUSION: R753Q SNP impairs TLR2-mediated immune recognition of HCV core and NS3 proteins. This biologic defect may account for the predisposition of patients to develop allograft failure after liver transplantation for chronic hepatitis C.

The impact of invasive fungal diseases on survival after lung transplantation.

BACKGROUND: Recipients of lung transplants are at high risk of infectious complications. We investigated the epidemiology of infections after lung transplantation and determined their impact on survival. METHODS: We retrospectively reviewed the medical records of patients who underwent lung transplantation at Mayo Clinic (Rochester) during 1990-2005. Survival analyses were performed using Kaplan-Meier estimation and Cox proportional hazard modeling. RESULTS: Sixty-nine lung transplants were performed during the 16-yr study period. The mean (+/-SD) patient age was 50.5 +/- 9.7 yr; 45% were male. During the mean (+/-SD) follow-up period of 1188 (+/-1288) d, the cumulative percentage of patients with infections were: bacteria (52%), cytomegalovirus (CMV) (49%), other viruses (32%), fungi (19%), mycobacteria (7%), and Pneumocystis jiroveci (1%). The median survival time after lung transplantation was 5.02 yr. Kaplan-Meier estimation of one-, three-, and five-yr survival was 80%, 61%, and 50%, respectively. Overall, 37 (54%) patients died due to graft rejection and failure (35%), invasive fungal diseases (16%), post-transplant lymphoproliferative disorder and other malignancies (14%), cardiovascular diseases (5%), CMV disease (3%), bacterial infection (3%), or other causes (24%). Survival analysis using Kaplan-Meier estimation showed that invasive fungal disease (Aspergillus sp., n = 9, Candida sp., n = 2, Alternaria sp., n = 1, Rhizopus sp., n = 1, and/or Mucor sp., n = 1) was significantly associated with mortality (p = 0.0104). After adjusting for age and graft rejection, invasive fungal disease remains a significant predictor of mortality (p = 0.0262). CONCLUSION: Invasive fungal disease is significantly associated with all-cause mortality after lung transplantation. An aggressive antifungal preventive strategy may lead to improved survival after lung transplantation.

A prospective longitudinal analysis of cytomegalovirus (CMV)-specific CD4+ and CD8+ T cells in kidney allograft recipients at risk of CMV infection.

Cytomegalovirus (CMV)-specific cellular immunity is essential in controlling CMV infection after transplantation. We investigated whether CMV-specific T cell levels predict CMV DNAemia after kidney transplantation. Using cytokine-flow cytometry, we enumerated interferon-gamma producing CMV-specific CD4+ and CD8+ T cells at serial time points among CMV-mismatched (D+/R-) and seropositive (R+) kidney recipients who received 3 months of valganciclovir prophylaxis. Among 44 patients, eight (18%) developed CMV DNAemia at a mean (+ or - SD) time of 151 (+ or - 33) days after transplantation, including two (5%) with CMV syndrome and three (7%) with tissue-invasive CMV disease. Cox proportional hazards regression analysis showed that CMV mismatch (D+/R-) status (HR: 13, 95% CI: 1.6-106.4; P = 0.02) and diabetes mellitus (HR: 5.6; 95%CI: 1.1-27.9; P = 0.03) were significantly associated with CMV DNAemia. In contrast, the percentage or change-over-time in CMV-specific CD4+ [pp65 (P = 0.45), or CMV lysate (P = 0.22)] and CD8+ [pp65 (P = 0.43), or IE-1 (P = 0.37)] T cells were not significantly associated with CMV DNAemia. CMV-specific T cell assays have limited clinical utility among CMV R+ kidney recipients who received valganciclovir prophylaxis. On the other hand, the clinical utility of CMV-specific T cell assays will need to be assessed in a larger cohort of CMV D+/R- kidney recipients who remain at high-risk of delayed-onset CMV disease.

Emergence of drug-resistant cytomegalovirus in the era of valganciclovir prophylaxis: therapeutic implications and outcomes.

BACKGROUND: Valganciclovir prophylaxis is reportedly associated with a low incidence of ganciclovir-resistant cytomegalovirus (CMV). We assessed the incidence, clinical features, and outcome of drug-resistant CMV among solid organ transplant patients who received valganciclovir prophylaxis. METHODS: The medical records of all CMV D+/R- kidney, pancreas, liver, and heart recipients were screened for CMV disease, and the clinical course and outcomes of patients with drug-resistant CMV were reviewed. RESULTS: During a four-yr-study period, a total of 225 CMV D+/R- transplant patients received valganciclovir prophylaxis for a median of 92 d. Sixty-five (29%) of the 225 patients developed delayed-onset primary CMV disease, including nine (14%) suspected to have drug-resistant virus. Four (6.2%) had confirmed UL97 or UL54 mutations. All except one patient manifested gastrointestinal tissue-invasive disease. Together with reduction in immunosuppression, intravenous foscarnet with or without CMV hyperimmunoglobulin was the most common treatment. Drug-associated nephrotoxicity was commonly observed and resulted in allograft loss in two patients. During the mean follow-up of 2.2 yr, allograft loss and mortality occurred in two of four patients with proven and in three of five patients with clinically suspected drug-resistant CMV. CONCLUSIONS: Cytomegalovirus disease because of clinically suspected or genotypically confirmed drug-resistant CMV is not uncommon in CMV D+/R- solid organ transplant patients who received valganciclovir prophylaxis. Because of its significant morbidity and mortality, an optimized strategy of CMV prevention is warranted to reduce the negative impact of drug-resistant CMV on the successful outcome of organ transplantation.

Delayed-onset primary cytomegalovirus disease and the risk of allograft failure and mortality after kidney transplantation.

BACKGROUND: During the contemporary era of antiviral prophylaxis, the impact of delayed-onset primary cytomegalovirus (CMV) disease on the outcome of kidney transplantation is not known. We evaluated the incidence, clinical features, risk factors, and outcomes of CMV disease among high-risk kidney transplant recipients. METHODS: The medical records of CMV-seronegative recipients of kidney transplants from CMV-seropositive donors were reviewed. Cox proportional hazards regression was used to identify factors associated with CMV disease and to assess its impact on allograft loss and mortality. RESULTS: None of the 176 CMV-seronegative recipients of kidney transplants from CMV-seropositive donors developed breakthrough CMV disease during a median of 92 days (interquartile range, 90-92 days) of oral ganciclovir or valganciclovir prophylaxis. Thereafter, 51 patients (29%) developed CMV disease at a median of 61 days (interquartile range, 40-143 days) after stopping antiviral prophylaxis. Early-onset bacterial and fungal infection (hazard ratio, 3.61; 95% confidence interval, 1.78-7.33; p < .001) and a Charlson comorbidity index > or =3 (hazard ratio, 2.21; 95% confidence interval, 1.15-4.22; p = .011) were associated with a higher risk of delayed-onset primary CMV disease, and postrejection antiviral prophylaxis (hazard ratio, 0.29; 95% confidence interval, 0.09-0.94; P = .039) was associated with a lower risk of such CMV disease. A time-dependent Cox regression analysis revealed a statistically significant association between tissue-invasive CMV disease and allograft loss or mortality (hazard ratio, 2.85; 95% confidence interval, 1.22-6.67; P = .016). CONCLUSION: This study of a large cohort of CMV-seronegative recipients of kidney transplants from CMV-seropositive donors illustrates the ongoing challenge of delayed-onset primary CMV disease and its impact on transplantation outcomes despite antiviral prophylaxis. Better strategies for CMV disease prevention after kidney transplantation are warranted.