Two Cases of Possible Exacerbation of Chronic Rejection After Anti-SARS-CoV-2 Messenger RNA Vaccination: A Case Report.

In post-liver transplant recipients, SARS-CoV-2 infection is a health threat, and novel messenger RNA vaccines such as Pfizer BioNTech BNT162b2 and Moderna mRNA-1273 are aggressively recommended. However, there are few reports on their adverse effects, some of which may be potentially fatal. We have experienced 2 post-liver transplant recipients with exacerbated chronic rejection after vaccination, one of whom had to undergo retransplant and the other who is still in the process of liver function without improvement. These alarming cases will be presented as case reports.

First use of imlifidase desensitization in a highly sensitized lung transplant candidate: a case report.

Lung transplant candidates who are highly sensitized against human leucocyte antigen present an ongoing challenge with regards to finding immunologically acceptable donors. Desensitization strategies aimed at reducing preformed donor-specific antibodies have a number of limitations. Imlifidase, an IgG-degrading enzyme derived from Streptococcus pyogenes, is a novel agent that has been used to convert positive crossmatches to negative in kidney transplant candidates, allowing transplantation to occur. We present the first case of imlifidase use for antibody depletion in a highly sensitized lung transplant candidate who went on to undergo a successful bilateral lung transplant.

Optimal dose of rituximab in ABO-incompatible kidney transplantation in patients with low anti-A/B antibody titers: A single-center retrospective cohort study.

BACKGROUND: The clinical outcomes of ABO-incompatible (ABOi) kidney transplantation have improved with the introduction of desensitization therapy with rituximab. However, rituximab prevents not only antibody-mediated rejection (AMR) but also increases the risk of adverse events, such as infection. For ABOi kidney transplantation in patients with low anti-A/B antibody titers, we previously used a rituximab-free desensitization protocol and then initiated a single dose of 100 mg rituximab in 2016. We retrospectively compared the outcomes of ABOi kidney transplantation in patients with low anti-A/B antibody titers before and after the introduction of rituximab. METHODS: ABOi kidney transplantations (n = 142) in patients with low anti-A/B antibody titers between 2007 and 2021 were included. Patients were divided into two groups (with and without rituximab) for desensitization. The primary outcomes were the incidence of acute AMR and infection. RESULTS: Sixty-six patients were desensitized without rituximab (rituximab-free group), and 76 were pretreated with 100 mg rituximab (rituximab group) before transplantation. The incidence of acute AMR was significantly lower in the rituximab group than in the rituximab-free group (.0% [0/76] vs. 7.6% [5/66], respectively; p = .047). Post-transplantation anti-A/B antibody titers were also lower in the rituximab group than in the rituximab-free group. There was no significant difference in the incidence of adverse events, including infections, between the two groups. CONCLUSION: In ABOi kidney transplantation patients with low anti-A/B antibody titers, the desensitization protocol with a single dose of 100 mg rituximab was effective in preventing acute AMR without increasing the risk of other adverse events.

Late antibody-mediated rejection in a kidney transplant recipient: COVID 19 induced?

BACKGROUND: Antibody-mediated rejection (AMR) was described in kidney transplant patients after viral infections, such as the cytomegalovirus. Very few cases were recently reported after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, probably in the context of lowering of immunosuppressive therapy. To date, no direct immunological link was proved to explain a connection between the coronavirus disease 19 (COVID-19) infection and antibody-mediated rejection (AMR) if it exists. CASE PRESENTATION: Here we try to find this association by presenting the case of a low immunological risk patient who presented, six years post-transplant, with c4d negative antibody mediated rejection due to an anti-HLA-C17 de novo donor specific antibody (DSA) after contracting the coronavirus disease 19. The HLA-Cw17 activated the antibody-dependent cell-mediated cytotoxicity via the KIR2DS1 positive NK cells. DISCUSSION AND CONCLUSIONS: This case report may prove a direct role for COVID-19 infection in AMRs in the kidney transplant recipients, leading us to closely monitor kidney transplant recipients, especially if they have "at-risk" donor antigens.

COVID-19 Vaccination May Not Increase Rates of Corneal Graft Rejection.

PURPOSE: The aim of the study was to present the rates of rejection from 2018 to 2021 and evaluate the purported association between COVID-19 vaccination and corneal graft rejection. METHODS: Cases of corneal graft rejection diagnosed between January 2018 and December 2021 were reviewed. The conditional Poisson regression model of the self-controlled case series method was used to estimate the incidence risk ratio of graft rejection after COVID-19 vaccination risk period compared with the control period. Based on outcomes of eyes that underwent keratoplasty from January 2018 to December 2020, Cox proportional hazard models were fitted with previous COVID-19 vaccination as a time-varying covariate. RESULTS: Over the past 4 years, the annual tally of diagnosed cases of graft rejection (19 cases in year 2018, 19 cases in year 2019, 21 cases in year 2020, and 18 cases in year 2021) has remained relatively stable. Using the conditional Poisson regression analysis, no significant increase in the incidence rate of rejection in the risk period after COVID-19 vaccination was found (incidence risk ratio = 0.56, 95% confidence interval [CI] = 0.13-2.28, P = 0.70). Fitted as a time-varying covariate, previous COVID-19 vaccination was not associated with graft rejection in both unadjusted (hazard ratio =0.77, 95% CI = 0.29-5.46, P = 0.77) and adjusted Cox models (hazard ratio = 0.75, 95% CI = 0.10-5.52, P = 0.78). CONCLUSIONS: No notable increase in rates of corneal graft rejection was noted in year 2021 when COVID-19 vaccination was broadly implemented. The apparent temporal relationship between COVID vaccination and corneal graft rejection may not represent a causative association.

A pilot randomized controlled trial of de novo belatacept-based immunosuppression following anti-thymocyte globulin induction in lung transplantation.

The development of donor-specific antibodies (DSA) after lung transplantation is common and results in adverse outcomes. In kidney transplantation, Belatacept has been associated with a lower incidence of DSA, but experience with Belatacept in lung transplantation is limited. We conducted a two-center pilot randomized controlled trial of de novo immunosuppression with Belatacept after lung transplantation to assess the feasibility of conducting a pivotal trial. Twenty-seven participants were randomized to Control (Tacrolimus, Mycophenolate Mofetil, and prednisone, n = 14) or Belatacept-based immunosuppression (Tacrolimus, Belatacept, and prednisone until day 89 followed by Belatacept, Mycophenolate Mofetil, and prednisone, n = 13). All participants were treated with rabbit anti-thymocyte globulin for induction immunosuppression. We permanently stopped randomization and treatment with Belatacept after three participants in the Belatacept arm died compared to none in the Control arm. Subsequently, two additional participants in the Belatacept arm died for a total of five deaths compared to none in the Control arm (log rank p = .016). We did not detect a significant difference in DSA development, acute cellular rejection, or infection between the two groups. We conclude that the investigational regimen used in this study is associated with increased mortality after lung transplantation.

Heart transplant recipient 1-year outcomes during the COVID-19 pandemic.

The COVID-19 pandemic initially brought forth considerable challenges to the field of heart transplantation. To prevent the spread of the virus and protect immunocompromised recipients, our center made the following modifications to post-transplant outpatient management: eliminating early coronary angiograms, video visits for postoperative months 7, 9, and 11, and home blood draws for immunosuppression adjustments. To assess if these changes have impacted patient outcomes, the current study examines 1-year outcomes for patients transplanted during the pandemic. Between March and September 2020, we assessed 50 heart transplant patients transplanted during the pandemic. These patients were compared to patients who were transplanted during the same months between 2011 and 2019 (n = 482). Endpoints included subsequent 1-year survival, freedom from cardiac allograft vasculopathy, any-treated rejection, acute cellular rejection, antibody-mediated rejection, nonfatal major adverse cardiac events (NF-MACE), and hospital and ICU length of stay. Patients transplanted during the pandemic had similar 1-year endpoints compared to those of patients transplanted from years prior apart from 1-year freedom from NF-MACE which was significantly higher for patients transplanted during the pandemic. Despite necessary changes being made to outpatient management of heart transplant recipients, heart transplantation continues to be safe and effective with similar 1-year outcomes to years prior.

"Smoldering" Rejection of Keratolimbal Allograft.

PURPOSE: The purpose of this study was to report a case of "smoldering" keratolimbal allograft (KLAL) rejection in a patient with subtherapeutic levels of systemic immunosuppression in temporal association with BNT162b2 messenger RNA vaccination for severe acute respiratory syndrome coronavirus 2. METHODS: This was a case report. OBSERVATIONS: A 72-year-old man presented with circumferential perilimbal engorgement, stagnation, and tortuosity of vessels with mild chemosis in his right eye KLAL segments 1 month after receiving the BNT162b2 messenger RNA vaccine while his tacrolimus trough blood levels were subtherapeutic measuring <2 ng/mL. He had undergone KLAL 6.5 years before for total limbal stem cell deficiency from a chemical injury and had been stable without any history of rejection. The donor was blood type O, and the patient had no systemic comorbidities. The patient was treated with hourly difluprednate 0.05% and increasing of his oral tacrolimus dose to 2 mg twice a day with improvement of rejection signs. CONCLUSIONS: There may be a temporal association between KLAL rejection after immunization against severe acute respiratory syndrome coronavirus 2 in patients with subtherapeutic levels of systemic immunosuppression. Patients should be on alert for any ocular signs or symptoms postimmunization and present for treatment immediately.

Corneal Graft Rejection After Inactivated SARS-CoV-2 Vaccine: Case Report.

PURPOSE: Our aim was to report the case of endothelial corneal allograft rejection after inactivated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine with an atypical presentation. METHODS: This was a case report. RESULTS: A 63-year-old woman with previous penetrating keratoplasty and laser in situ keratomileusis presented with clinical signs of endothelial corneal graft rejection 24 hours after CoronaVac (SinoVac Biotech, Beijing/China) vaccine. Slitlamp examination showed corneal edema and interface fluid accumulation. It was partially resolved after treatment with topical corticosteroids and polydimethylsiloxane. CONCLUSIONS: Corneal allograft rejection was already reported after another SARS-CoV-2 vaccine. This is the first report in the literature describing a possible association with inactivated SARS-CoV-2 vaccine and corneal allograft rejection, especially with laser in situ keratomileusis interface fluid accumulation presentation. Ophthalmologists should be aware of this potential complication.

Acute Corneal Epithelial Rejection of LR-CLAL After SARS-CoV-2 Vaccination.

PURPOSE: The purpose of this study was to report a case of acute corneal epithelial rejection of living-related conjunctival limbal allograft (LR-CLAL) after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination. OBSERVATIONS: A 27-year-old woman developed acute epithelial rejection of LR-CLAL 2 weeks after receiving the SARS-CoV-2 vaccine. She received the LR-CLAL transplant 4 years and 7 months previously and had a stable clinical course with no history of rejection. She had an ABO blood group and human leukocyte antigen compatible donor, no systemic comorbidities, and no rejection risk factors. CONCLUSIONS: The novel SARS-CoV-2 vaccine upregulates the immune system to produce an adaptive immune response. The SARS-CoV-2 vaccine may potentially be associated with increased risk of rejection in those with ocular surface transplants.

Missing Self-Induced Activation of NK Cells Combines with Non-Complement-Fixing Donor-Specific Antibodies to Accelerate Kidney Transplant Loss in Chronic Antibody-Mediated Rejection.

BACKGROUND: Binding of donor-specific antibodies (DSAs) to kidney allograft endothelial cells that does not activate the classic complement cascade can trigger the recruitment of innate immune effectors, including NK cells. Activated NK cells contribute to microvascular inflammation leading to chronic antibody-mediated rejection (AMR). Recipient NK cells can also trigger antibody-independent microvascular inflammation by sensing the absence of self HLA class I molecules ("missing self") on allograft endothelial cells. This translational study investigated whether the condition of missing self amplifies DSA-dependent NK cell activation to worsen chronic AMR. METHODS AND RESULTS: Among 1682 kidney transplant recipients who underwent an allograft biopsy at Lyon University Hospital between 2004 and 2017, 135 fulfilled the diagnostic criteria for AMR and were enrolled in the study. Patients with complement-fixing DSAs identified by a positive C3d binding assay (n=73, 54%) had a higher risk of transplant failure (P=0.002). Among the remaining patients with complement-independent chronic AMR (n=62, 46%), those in whom missing self was identified through donor and recipient genotyping exhibited worse allograft survival (P=0.02). In multivariable analysis, only proteinuria (HR: 7.24; P=0.01) and the presence of missing self (HR: 3.57; P=0.04) were independent predictors for transplant failure following diagnosis of chronic AMR. Cocultures of human NK cells and endothelial cells confirmed that addition of missing self to DSA-induced NK cell activation increased endothelial damage. CONCLUSIONS: The assessment of missing self at the time of diagnosis of chronic AMR identifies patients at higher risk for kidney transplant failure.

Acute Corneal Transplant Rejection After Severe Acute Respiratory Syndrome Coronavirus 2 mRNA-1273 Vaccination.

PURPOSE: The purpose of this article was to report a case of full-thickness corneal transplant rejection 3 days after immunization with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Moderna mRNA-1273 vaccine. METHODS: Case Report. RESULTS: A 51-year-old man with a history of keratoconus and penetrating keratoplasty underwent repeat penetrating keratoplasty for graft failure. The patient had an uncomplicated intraoperative and postoperative course with improved vision and a healthy graft. The patient received the SARS-CoV-2 Moderna vaccine on postoperative week 3, and within 3 days, the patient began developing eye pain, photophobia, and blurred vision. The patient was found to have graft rejection with corneal edema and endothelial keratic precipitates. The rejection did not improve despite a trial of increased topical steroids and ultimately evolved into graft failure. CONCLUSIONS: To the best of our knowledge, this case of full-thickness graft rejection after the Moderna SARS-CoV-2 mRNA vaccination is the first to be reported worldwide. The temporal relationship between vaccination and subsequent rejection is highly suggestive of causation due to the short interval (3 days) between vaccination and rejection and the lack of other inciting factors in an otherwise healthy graft. Patients with corneal transplants who plan to take the COVID-19 vaccinations should be counseled on symptoms and closely monitored, and an individualized plan should be made in discussion with the ophthalmologist.

Acute Corneal Transplant Rejection After COVID-19 Vaccination.

PURPOSE: The purpose of this report was to describe 4 cases of acute corneal transplant rejection occurring in association with coronavirus disease 2019 (COVID-19) mRNA vaccination. METHODS: Four patients with prior keratoplasty developed presumed immunologic rejection after the mRNA-1273 vaccination for coronavirus 2 (SARS-CoV-2). Case 1 had received Descemet membrane endothelial keratoplasty 6 months ago and presented with endothelial graft rejection 3 weeks after the first vaccine dose. Case 2 had undergone penetrating keratoplasty 3 years previously and presented with acute endothelial rejection 9 days after the second vaccine dose. Case 3 had prior Descemet stripping automated endothelial keratoplasty (DSAEK) and began experiencing symptoms of endothelial graft rejection 2 weeks after the second vaccine dose. Case 4 presented with endothelial rejection of the penetrating keratoplasty graft 2 weeks after the second vaccine dose. RESULTS: Frequent topical corticosteroids alone were initiated in all 4 cases. In case 1, the endothelial rejection line appeared fainter with improvement in visual acuity and corneal edema 5 weeks after diagnosis. Case 2 experienced complete resolution of corneal stromal edema and rejection line 6 weeks after diagnosis. Cases 3 and 4 have both experienced initial improvement with steroid treatment as well. CONCLUSIONS: These cases suggest acute corneal endothelial rejection may occur soon after either dose of the COVID-19 mRNA vaccine. Prompt initiation of aggressive topical steroid therapy may result in complete resolution of clinical signs and symptoms. Further studies are needed to elucidate the causal mechanism of corneal graft rejection after COVID-19 vaccination.

Histopathologic findings on indication renal allograft biopsies after recovery from acute COVID-19.

Current knowledge on histopathological changes occurring after COVID-19 in transplanted kidneys is limited. Herein, we present renal allograft pathology findings in patients recovered from COVID-19. Six patients underwent indication biopsy, and one required allograft nephrectomy after acute COVID-19. Demographic data, clinical characteristics, and laboratory findings were recorded. The histopathological analysis included light microscopy, immunostaining, and electron microscopy. Five patients were hospitalized for acute COVID-19, and all were diagnosed with imaging-confirmed pneumonia, one requiring mechanical ventilation, and two requiring dialysis. Two patients had mild form. Histopathologic examination of renal allograft specimens revealed collapsing, perihilar, tip-lesion and secondary FSGS in one patient each. One patient had borderline acute cellular rejection, and two had chronic antibody-mediated rejection. Histopathologic changes of glomerular tufts were accompanied by acute tubular injury in four patients. None of our patients had signs of viral inclusions in kidney cells. One patient died and one remained dialysis-dependent after the good initial response to treatment. Patients with collapsing and perihilar FSGS had further progression of their chronic allograft nephropathy still without need for dialysis. In conclusion, diverse kidney pathology may be found in SARS-CoV-2-infected renal transplant patients. It seems that viral infection may affect the immune system with triggering of glomerular diseases, while the acute tubular injury is of multifactorial etiology. Direct viral effect is less likely.

Kidney allograft biopsy findings after COVID-19.

COVID-19 has been associated with acute kidney injury and published reports of native kidney biopsies have reported diverse pathologies. Case series directed specifically to kidney allograft biopsy findings in the setting of COVID-19 are lacking. We evaluated 18 kidney transplant recipients who were infected with SARS-CoV-2 and underwent allograft biopsy. Patients had a median age of 55 years, six were female, and five were Black. Fifteen patients developed COVID-19 pneumonia, of which five required mechanical ventilation. Notably, five of 11 (45%) biopsies obtained within 1 month of positive SARS-CoV-2 PCR showed acute rejection (four with arteritis, three of which were not associated with reduced immunosuppression). The remaining six biopsies revealed podocytopathy (n = 2, collapsing glomerulopathy and lupus podocytopathy), acute tubular injury (n = 2), infarction (n = 1), and transplant glomerulopathy (n = 1). Biopsies performed >1 month after positive SARS-CoV-2 PCR revealed collapsing glomerulopathy (n = 1), acute tubular injury (n = 1), and nonspecific histologic findings (n = 5). No direct viral infection of the kidney allograft was detected by immunohistochemistry, in situ hybridization, or electron microscopy. On follow-up, two patients died and most patients showed persistent allograft dysfunction. In conclusion, we demonstrate diverse causes of kidney allograft dysfunction after COVID-19, the most common being acute rejection with arteritis.

Diffuse C4d staining of peritubular capillaries in renal allograft following bamlanivimab therapy.

Neutralizing monoclonal antibodies such as bamlanivimab emerged as promising agents in treating kidney transplant recipients with COVID-19. However, the impact of bamlanivimab on kidney allograft histology remains unknown. We report a case of a kidney transplant recipient who received bamlanivimab for COVID-19 with subsequent histologic findings of diffuse peritubular capillary C4d staining. A 33-year-old man with end-stage kidney disease secondary to hypertension who received an ABO compatible kidney from a living donor, presented for his 4-month protocol visit. He was diagnosed with COVID-19 44 days prior to his visit and had received bamlanivimab with an uneventful recovery. His 4-month surveillance biopsy showed diffuse C4d staining of the peritubular capillaries without other features of antibody-mediated rejection (ABMR). Donor-specific antibodies were negative on repeat evaluations. ABMR gene expression panel was negative. His creatinine was stable at 1.3 mg/dl, without albuminuria. Given the temporal relationship between bamlanivimab and our observations of diffuse C4d staining of the peritubular capillaries, we hypothesize that bamlanivimab might bind to angiotensin-converting enzyme 2, resulting in classical complement pathway and C4d deposition. We elected to closely monitor kidney function which has been stable at 6 months after the biopsy. In conclusion, diffuse C4d may present following bamlanivimab administration without any evidence of ABMR.

Keratoplasty Rejection After the BNT162b2 messenger RNA Vaccine.

PURPOSE: The aim of this report was to report 2 patients who presented with acute corneal graft rejection 2 weeks after receiving the BNT162b2 messenger RNA (mRNA) vaccine for severe acute respiratory syndrome coronavirus 2. METHODS: Case report. RESULTS: Two men, aged 73 and 56 years, with a history of penetrating keratoplasty due to keratoconus were noted to have acute corneal graft rejection 2 weeks after receiving a first dose of the BNT162b2 mRNA vaccine. Both patients were treated with hourly dexamethasone 0.1% and oral prednisone 60 mg per day with prompt resolution of keratoplasty rejection. CONCLUSIONS: The BNT162b2 mRNA vaccine may be have been associated with a low-risk corneal graft rejection that responded well to topical and systemic steroids. Treating physicians should be aware of this potential complication and patients should be advised to report any visual changes after vaccination.

Characteristics of endothelial corneal transplant rejection following immunisation with SARS-CoV-2 messenger RNA vaccine.

AIM: We report two cases of endothelial corneal allograft rejection following immunisation with SARS-CoV-2 messenger RNA (mRNA) vaccine BNT162b2 and describe the implications for management of transplant recipients postvaccination for COVID-19. METHODS: A 66-year-old woman with Fuchs endothelial corneal dystrophy (FECD) and a unilateral Descemet's membrane endothelial keratoplasty (DMEK) transplant received COVID-19 mRNA vaccine BNT162b2 14 days post-transplant. Seven days later, she presented with symptoms and signs of endothelial graft rejection. An 83-year-old woman with bilateral DMEK transplants for FECD 3 and 6 years earlier developed simultaneous acute endothelial rejection in both eyes, 3 weeks post second dose of COVID-19 mRNA vaccine BNT162b2. Rejection in both cases was treated successfully with topical corticosteroids. CONCLUSIONS: We believe this is the first report of temporal association between corneal transplant rejection following immunisation against COVID-19 and the first report of DMEK rejection following any immunisation. We hypothesise that the allogeneic response may have been initiated by the host antibody response following vaccination. Clinicians and patients should be aware of the potential of corneal graft rejection associated with vaccine administration and may wish to consider vaccination in advance of planned non-urgent keratoplasties. Patients should be counselled on the symptoms and signs that require urgent review to allow early treatment of any confirmed rejection episode.