Long-term shedding of viable SARS-CoV-2 in kidney transplant recipients with COVID-19

The exact duration of viable SARS-CoV-2 shedding in kidney transplant recipients (KTRs) remains unclear. Here, we retrospectively investigated this issue using cell cultures of SARS-CoV-2 RT-PCR-positive nasopharyngeal samples (n = 40) obtained from 16 KTRs with symptomatic COVID-19 up to 39 days from symptom onset. A length of viable SARS-CoV-2 shedding >3 weeks from the onset of symptoms was identified in four KTRs (25%). These results suggest that a significant proportion of KTRs can shed viable SARS-CoV-2 for at least 3 weeks, which may favor the emergence of new variants. Based on these data, we recommend prolonging the isolation of KTRs with COVID-19 until negative SARS-CoV-2 RT-PCR testing.     

COVID-19 in lung transplant recipients: A multicenter study

This study describes the clinical presentation, treatment, and outcomes of SARS-CoV-2 infection in lung transplant recipients (LTRs). This is a multicenter, retrospective study of all adult LTRs with confirmed SARS-CoV-2 infection from March 4 until April 28, 2020 in six Spanish reference hospitals for lung transplantation. Clinical and radiological data, treatment characteristics, and outcomes were reviewed. Forty-four cases were identified in that period. The median time from transplantation was 4.2 (interquartile range: 1.11–7.3) years. Chest radiography showed acute parenchymal abnormalities in 32 (73%) cases. Hydroxychloroquine was prescribed in 41 (93%), lopinavir/ritonavir (LPV/r) in 14 (32%), and tocilizumab in 19 (43%) patients. There was a strong interaction between tacrolimus and LPV/r in all cases. Thirty-seven (84%) patients required some degree of respiratory support and/or oxygen therapy, and 13 (30%) were admitted to intermediate or intensive critical care units. Seventeen (39%) patients had died and 20 (45%) had been discharged at the time of the last follow-up. Deceased patients had a worse respiratory status and chest X-ray on admission and presented with higher D-dimer, interleukin-6, and lactate dehydrogenase levels. In this multicenter LTR cohort, SARS-CoV-2 presented with high mortality. Additionally, the severity of disease on presentation predicted subsequent mortality.     

Early clinical experience of bacteriophage therapy in 3 lung transplant recipients

Bacteriophage therapy (BT) uses bacteriophages to treat pathogenic bacteria and is an emerging strategy against multidrug‐resistant (MDR) infections. Experience in solid organ transplant is limited. We describe BT in 3 lung transplant recipients (LTR) with life‐threatening MDR infections caused by Pseudomonas aeruginosa (n = 2) and Burkholderia dolosa (n = 1). For each patient, lytic bacteriophages were selected against their bacterial isolates. BT was administered for variable durations under emergency Investigational New Drug applications and with patient informed consent. Safety was assessed using clinical/laboratory parameters and observed clinical improvements described, as appropriate. All patients received concurrent antibiotics. Two ventilator‐dependent LTR with large airway complications and refractory MDR P. aeruginosa pneumonia received BT. Both responded clinically and were discharged from the hospital off ventilator support. A third patient had recurrent B. dolosa infection following transplant. Following BT initiation, consolidative opacities improved and ventilator weaning was begun. However, infection relapsed on BT and the patient died. No BT‐related adverse events were identified in the 3 cases. BT was well tolerated and associated with clinical improvement in LTRs with MDR bacterial infection not responsive to antibiotics alone. BT may be a viable adjunct to antibiotics for patients with MDR infections.     

Natural influenza infection produces a greater diversity of humoral responses than vaccination in immunosuppressed transplant recipients

The humoral immune response to influenza virus infection is complex and may be different compared to the antibody response elicited by vaccination. We analyzed the breadth of IgG and IgA responses in solid organ transplant (SOT) recipients to a diverse collection of 86 influenza antigens elicited by natural influenza A virus (IAV) infection or by vaccination. Antibody levels were quantified using a custom antigen microarray. A total of 120 patients were included: 80 IAV infected (40 A/H1N1 and 40 A/H3N2) and 40 vaccinated. Based on hierarchical clustering analysis, infection with either H1N1 or H3N2 virus showed a more diverse antibody response compared to vaccination. Similarly, H1N1-infected individuals showed a significant IgG response to 27.9% of array antigens and H3N2-infected patients to 43.0% of antigens, whereas vaccination elicited a less broad immune response (7.0% of antigens). Immune responses were not exclusively targeting influenza hemagglutinin (HA) proteins but were also directed against conserved influenza antigens. Serum IgA responses followed a similar profile. This study provides novel data on the breadth of antibody responses to influenza. We also found that the diversity of response is greater in influenza-infected rather than vaccinated patients, providing a potential mechanistic rationale for suboptimal vaccine efficacy in this population.     

Cellular and humoral response after MRNA-1273 SARS-CoV-2 vaccine in kidney transplant recipients

According to preliminary data, seroconversion after mRNA SARS-CoV-2 vaccination might be unsatisfactory in Kidney Transplant Recipients (KTRs). However, it is unknown if seronegative patients develop at least a cellular response that could offer a certain grade of protection against SARS-CoV-2. To answer this question, we prospectively studied 148 recipients of either kidney (133) or kidney-pancreas (15) grafts with assessment of IgM/IgG spike (S) antibodies and ELISpot against the nucleocapside (N) and the S protein at baseline and 2 weeks after receiving the second dose of the mRNA-1273 (Moderna) vaccine. At baseline, 31 patients (20.9%) had either IgM/IgG or ELISpot positivity and were considered to be SARS-CoV-2-pre-immunized, while 117 (79.1%) patients had no signs of either cellular or humoral response and were considered SARS-CoV-2-naïve. After vaccination, naïve patients who developed either humoral or cellular response were finally 65.0%, of which 29.9% developed either IgG or IgM and 35.0% S-ELISpot positivity. Factors associated with vaccine unresponsiveness were diabetes and treatment with antithymocytes globulins during the last year. Side effects were consistent with that of the pivotal trial and no DSAs developed after vaccination. In conclusion, mRNA-1273 SARS-CoV-2 vaccine elicits either cellular or humoral response in almost two thirds of KTRs.     

Humoral and cellular immune response and safety of two-dose SARS-CoV-2 mRNA-1273 vaccine in solid organ transplant recipients

Solid organ transplant recipients are at high risk of severe disease from COVID-19. We assessed the immunogenicity of mRNA-1273 vaccine using a combination of antibody testing, surrogate neutralization assays, and T cell assays. Patients were immunized with two doses of vaccine and immunogenicity assessed after each dose using the above tests. CD4+ and CD8+ T cell responses were assessed in a subset using flow-cytometry. A total of 127 patients were enrolled of which 110 provided serum at all time points. A positive anti-RBD antibody was seen in 5.0% after one dose and 34.5% after two doses. Neutralizing antibody was present in 26.9%. Of note, 28.5% of patients with anti-RBD did not have neutralizing antibody. T cell responses in a sub-cohort of 48 patients showed a positive CD4+ T cell response in 47.9%. Of note, in this sub-cohort, 46.2% of patients with a negative anti-RBD, still had a positive CD4+ T cell response. The vaccine was safe and well-tolerated. In summary, immunogenicity of mRNA-1273 COVID-19 vaccine was modest, but a subset of patients still develop neutralizing antibody and CD4+T- cell responses. Importantly polyfunctional CD4+T cell responses were observed in a significant portion who were antibody negative, further highlighting the importance of vaccination in this patient population. IRB Statement: This study was approved by the University Health Network Research Ethics Board (CAPCR ID 20–6069).     

Letermovir in lung transplant recipients with cytomegalovirus infection: A retrospective observational study

Letermovir is a new antiviral drug approved for the prophylaxis of CMV infection in allogeneic stem cell transplants. The aim of the study was to assess the therapeutic efficacy of letermovir in difficult to treat CMV infections in lung transplant recipients. All lung transplant recipients between March 2018 and August 2020, who have been treated with letermovir for ganciclovir-resistant or refractory CMV infection were included in the study and analysed retrospectively. In total, 28 patients were identified. CMV disease was present in 15 patients (53.6%). In 23 patients (82.1%), rapid response was noticed, and CMV-viral load could be significantly decreased (>1 log₁₀) after a median of 17 [14–27] days and cleared subsequently in all of these patients. Five patients (17.9%) were classified as non-responder. Thereof, development of a mutation of the CMV UL56 terminase (UL-56-Gen: C325Y) conferring letermovir resistance could be observed in three patients (60%). Common side effects were mild and mostly of gastrointestinal nature. Mild adjustments of the immunosuppressive drugs were mandatory upon treatment initiation with letermovir. In addition to other interventions, letermovir was effective in difficult to treat CMV infections in lung transplant recipients. However, in patients with treatment failure mutation conferring letermovir, resistance should be taken into account.     

A systematic review and meta-analysis of COVID-19 in kidney transplant recipients: Lessons to be learned

Kidney transplant recipients (KTR) may be at increased risk of adverse COVID-19 outcomes, due to prevalent comorbidities and immunosuppressed status. Given the global differences in COVID-19 policies and treatments, a robust assessment of all evidence is necessary to evaluate the clinical course of COVID-19 in KTR. Studies on mortality and acute kidney injury (AKI) in KTR in the World Health Organization COVID-19 database were systematically reviewed. We selected studies published between March 2020 and January 18th 2021, including at least five KTR with COVID-19. Random-effects meta-analyses were performed to calculate overall proportions, including 95% confidence intervals (95% CI). Subgroup analyses were performed on time of submission, geographical region, sex, age, time after transplantation, comorbidities, and treatments. We included 74 studies with 5559 KTR with COVID-19 (64.0% males, mean age 58.2 years, mean 73 months after transplantation) in total. The risk of mortality, 23% (95% CI: 21%–27%), and AKI, 50% (95% CI: 44%–56%), is high among KTR with COVID-19, regardless of sex, age and comorbidities, underlining the call to accelerate vaccination programs for KTR. Given the suboptimal reporting across the identified studies, we urge researchers to consistently report anthropometrics, kidney function at baseline and discharge, (changes in) immunosuppressive therapy, AKI, and renal outcome among KTR.     

COVID‐19 pneumonia in lung transplant recipients: Report of 2 cases

Coronavirus disease 2019 (COVID‐19) has been declared pandemic since March 2020. In Europe, Italy was the first nation affected by this infection. We report anamnestic data, clinical features, and therapeutic management of 2 lung transplant recipients with confirmed COVID‐19 pneumonia. Both patients were in good clinical condition before the infection and were receiving immunosuppression with calcineurin inhibitors (CNI), mycophenolate mofetil, and corticosteroids. Whereas mycophenolate mofetil was withdrawn in both cases, CNI were suspended only in the second patient. The first patient always maintained excellent oxygen saturation throughout hospitalization with no need for additional oxygen therapy. He was discharged with a satisfactory pulmonary function and a complete resolution of radiological and clinical findings. However, at discharge SARS‐CoV‐2 RNA could still be detected in the nasopharyngeal swab and in the stools. The second patient required mechanical ventilation, had a progressive deterioration of his clinical conditions, and had a fatal outcome. Further insight into SARS‐CoV‐2 infection is eagerly awaited to improve the outcome of transplant recipients affected by COVID‐19 pneumonia.     

Inpatient COVID-19 outcomes in solid organ transplant recipients compared to non-solid organ transplant patients: A retrospective cohort

Immunosuppression and comorbidities might place solid organ transplant (SOT) recipients at higher risk from COVID-19, as suggested by recent case series. We compared 45 SOT vs. 2427 non-SOT patients who were admitted with COVID-19 to our health-care system (March 1, 2020 - August 21, 2020), evaluating hospital length-of-stay and inpatient mortality using competing-risks regression. We compared trajectories of WHO COVID-19 severity scale using mixed-effects ordinal logistic regression, adjusting for severity score at admission. SOT and non-SOT patients had comparable age, sex, and race, but SOT recipients were more likely to have diabetes (60% vs. 34%, p < .001), hypertension (69% vs. 44%, p = .001), HIV (7% vs. 1.4%, p = .024), and peripheral vascular disorders (19% vs. 8%, p = .018). There were no statistically significant differences between SOT and non-SOT in maximum illness severity score (p = .13), length-of-stay (sHR: _0.91.1_1.4, p = .5), or mortality (sHR: _0.10.4_1.6, p = .19), although the severity score on admission was slightly lower for SOT (median [IQR] 3 [3, 4]) than for non-SOT (median [IQR] 4 [3–4]) (p = .042) Despite a higher risk profile, SOT recipients had a faster decline in disease severity over time (OR = _0.760.81_0.86, p < .001) compared with non-SOT patients. These findings have implications for transplant decision-making during the COVID-19 pandemic, and insights about the impact of SARS-CoV-2 on immunosuppressed patients.

     

COVID-19 in transplant recipients: The Spanish experience

We report the nationwide experience with solid organ transplant (SOT) and hematopoietic stem cell transplant (HSCT) recipients diagnosed with coronavirus disease 2019 (COVID-19) in Spain until 13 July 2020. We compiled information for 778 (423 kidney, 113 HSCT, 110 liver, 69 heart, 54 lung, 8 pancreas, 1 multivisceral) recipients. Median age at diagnosis was 61 years (interquartile range [IQR]: 52-70), and 66% were male. The incidence of COVID-19 in SOT recipients was two-fold higher compared to the Spanish general population. The median interval from transplantation was 59 months (IQR: 18-131). Infection was hospital-acquired in 13% of cases. No donor-derived COVID-19 was suspected. Most patients (89%) were admitted to the hospital. Therapies included hydroxychloroquine (84%), azithromycin (53%), protease inhibitors (37%), and interferon-β (5%), whereas immunomodulation was based on corticosteroids (41%) and tocilizumab (21%). Adjustment of immunosuppression was performed in 85% of patients. At the time of analysis, complete follow-up was available from 652 patients. Acute respiratory distress syndrome occurred in 35% of patients. Ultimately, 174 (27%) patients died. In univariate analysis, risk factors for death were lung transplantation (odds ratio [OR]: 2.5; 95% CI: 1.4-4.6), age >60 years (OR: 3.7; 95% CI: 2.5-5.5), and hospital-acquired COVID-19 (OR: 3.0; 95% CI: 1.9-4.9).     

Burden,epidemiology, and outcomes of microbiologically confirmed respiratory viral infections in solid organ transplant recipients: a nationwide,multi-season prospective cohort study

Solid organ transplant (SOT) recipients are exposed to respiratory viral infection (RVI) during seasonal epidemics; however, the associated burden of disease has not been fully characterized. We describe the epidemiology and outcomes of RVI in a cohort enrolling 3294 consecutive patients undergoing SOT from May 2008 to December 2015 in Switzerland. Patient and allograft outcomes, and RVI diagnosed during routine clinical practice were prospectively collected. Median follow-up was 3.4 years (interquartile range 1.61–5.56). Six hundred ninety-six RVIs were diagnosed in 151/334 (45%) lung and 265/2960 (9%) non-lung transplant recipients. Cumulative incidence was 60% (95% confidence interval [CI] 53%-69%) in lung and 12% (95% CI 11%-14%) in non-lung transplant recipients. RVI led to 17.9 (95% CI 15.7–20.5) hospital admissions per 1000 patient-years. Intensive care unit admission was required in 4% (27/691) of cases. Thirty-day all-cause case fatality rate was 0.9% (6/696). Using proportional hazard models we found that RVI (adjusted hazard ratio [aHR] 2.45; 95% CI 1.62–3.73), lower respiratory tract RVI (aHR 3.45; 95% CI 2.15–5.52), and influenza (aHR 3.57; 95% CI 1.75–7.26) were associated with graft failure or death. In this cohort of SOT recipients, RVI caused important morbidity and may affect long-term outcomes, underlying the need for improved preventive strategies.     

Salvage therapy with topical posaconazole in lung transplant recipients with invasive Scedosporium infection

Scedosporium is an important pathogen in cystic fibrosis (CF) and post‐transplantation, but it rarely causes invasive infection. Treatment remains challenging, particularly due to the inherent resistance to multiple antifungal agents. We present 3 complicated invasive tracheobronchial and lung Scedosporium apiospermum infections following lung transplantation. In 2 of 3 cases, the infection was clinically and radiologically cured with frequent cleansing bronchoscopies, combining triazole with terbinafine therapy and nebulized posaconazole. These cases highlight the importance of adjunctive nebulized therapy in addition to prolonged triazole treatment to manage complex invasive Scedosporium infections in immunosuppressed patients. Posaconazole (PSZ) was delivered during the bronchoscopy procedure through intrabronchial administration, whereas an eFlow rapid^® device was used for nebulized therapy. Topical posaconazole was well tolerated in 2 patients, with only a slight cough during administrations; the third patient had local irritation with poor tolerance, which led to its withdrawal. This is the first report on compassionate use of topical PSZ as salvage therapy for resistant mold infections in lung transplant recipients. These 3 cases represent the entire experience using this approach; no additional patients have received this therapy due to there not having been any additional cases of Scedosporium tracheobronchitis presented.     

Measles outbreak risk assessment for transplant candidates and recipients

Solid organ transplant (SOT) candidates and recipients are at risk of significant morbidity and mortality from infection, including those circulating in the community from unexpected outbreaks. In late 2018-summer of 2019, a measles outbreak occurred in the New York City area, with a total of 649 cases reported. We developed a systematic 3-part approach to address measles risk in our adult SOT program through: (a) identification of nonimmune adults living in outbreak ZIP codes, (b) education focused on risk reduction for patients from outbreak ZIP codes, and (c) risk reduction for nonimmune patients. All waitlisted or previously transplanted patients residing in outbreak areas received a measles patient education handout. The electronic medical record of patients born in or after 1957 was reviewed for serologic evidence of measles immunity. Measles immunity testing was performed in patients without documentation of immunity. Patients who tested nonimmune were offered MMR vaccination or intravenous immunoglobulin depending on their transplant phase and risk profile. Thus, we demonstrate successful implementation of a systematic risk assessment during a large measles outbreak to identify and protect at-risk SOT patients. As vaccine hesitancy persists, our strategies may be increasingly relevant to transplant centers and those caring for immunocompromised patients.     

First experience of SARS‐CoV‐2 infections in solid organ transplant recipients in the Swiss Transplant Cohort Study

Immunocompromised patients may be at increased risk for complications of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) infection. However, comprehensive data of SARS‐CoV‐2 infection in solid organ transplant (SOT) recipients are still lacking. We performed a multicenter nationwide observational study within the Swiss Transplant Cohort Study (STCS) to describe the epidemiology, clinical presentation, treatment and outcomes of the first microbiologically documented SARS‐CoV‐2 infection among SOT recipients. Overall, 21 patients were included with a median age of 56 years (10 kidney, 5 liver, 1 pancreas, 1 lung, 1 heart and 3 combined transplantations). The most common presenting symptoms were fever (76%), dry cough (57%), nausea (33%), and diarrhea (33%). Ninety‐five percent and 24% of patients required hospital and ICU admission, respectively, and 19% were intubated. After a median of 33 days of follow‐up, 16 patients were discharged, 3 were still hospitalized and 2 patients died. These data suggest that clinical manifestations of SARS‐CoV‐2 infection in middle‐aged SOT recipients appear to be similar to the general population without an apparent higher rate of complications. These results need to be confirmed in larger cohorts.     

Immunity to varicella,measles, and mumps in patients evaluated for lung transplantation

Vaccine-preventable viral infections are associated with increased risk of morbidity and mortality in post-transplant patients on immunosuppression regimens. Therefore, we studied rates of immunity against vaccine-preventable viruses in lung transplantation (LTx) candidates and their associations with underlying lung disease and clinical characteristics. We retrospectively studied 1025 consecutive adult patients who underwent first-time evaluation for LTx at a single center between January 2016 and October 2018. Viruses studied included varicella zoster (VZV), measles, and mumps. Young age (17–48 years old) was negatively associated with immunity for VZV (OR 4.54, p < .001), measles (OR 15.45, p < .001) and mumps (OR 3.1, p < .001), as compared to those 65+. Many LTx candidates with cystic fibrosis (CF) had undetectable virus-specific antibody titers including: 13.5% for VZV, 19.1% for measles, and 15.7% for mumps with significant odds of undetectable titers for VZV (OR 4.54, p < .001) and measles (OR 2.32, p = .010) as compared to those without CF. Therefore, a substantial number of patients undergoing LTx evaluation had undetectable virus-specific antibody titers. Our results emphasize the importance of screening for immunity to vaccine-preventable infections in this population and the need for revaccination in selected patients to boost their humoral immunity prior to transplantation.

     

COVID-19 severity in kidney transplant recipients is similar to nontransplant patients with similar comorbidities

Higher rates of severe COVID-19 have been reported in kidney transplant recipients (KTRs) compared to nontransplant patients. We aimed to determine if poorer outcomes were specifically related to chronic immunosuppression or underlying comorbidities. We used a 1:1 propensity score-matching method to compare survival and severe disease-free survival (defined as death and/or need for intensive care unit [ICU]) incidence in hospitalized KTRs and nontransplant control patients between February 26 and May 22, 2020. Patients were matched for risk factors of severe COVID-19: age, sex, body mass index, diabetes mellitus, preexisting cardiopathy, chronic lung disease, and basal renal function. We included 100 KTRs (median age [interquartile range (IQR)]) 64.7 years (55.3–73.1) in three French transplant centers. After a median follow-up of 13 days (7–30), transfer to ICU was required for 34 patients (34%) and death occurred in 26 patients (26%). Overall, 43 patients (43%) developed a severe disease during a median follow-up of 8.5 days (2–14). Propensity score matching to a large French cohort of 2017 patients hospitalized in 24 centers, revealed that survival was similar between KTRs and matched nontransplant patients with respective 30-day survival of 62.9% and 71% (p = .38) and severe disease-free 30-day survival of 50.6% and 47.5% (p = .91). These findings suggest that severity of COVID-19 in KTRs is related to their associated comorbidities and not to chronic immunosuppression.