Acute Transplant Failure Research Articles

COVID-19 associated acute transplant failure after AB0-incompatible living donor kidney transplantation – a case report

IntroductionImmunosuppressive therapy is associated with an increased risk of severe courses of SARS-CoV-2 infection, with frequently delayed viral clearance. We report a case of an acute kidney transplant failure in persistent SARS-CoV-2 infection in a patient with absolute B-cell depletion after administration of rituximab for AB0-incompatible living donor kidney transplantation.Case presentationA 34-year-old unvaccinated patient is diagnosed with SARS-CoV-2 infection four months after kidney transplantation. With only mild symptoms and an estimated glomerular filtration rate (eGFR) of 44 ml/min/1.73 m2, therapy with molnupiravir was initially given. Within the next eight weeks, transplant biopsies were performed for acute graft failure. These showed acute T-cell rejection with severe acute tubular epithelial damage with only mild interstitial fibrosis and tubular atrophy (BANFF cat. 4 IB), and borderline rejection (BANFF cat. 3). A therapy with prednisolone and intravenous immunoglobulins was performed twice. With unchanged graft failure, the third biopsy also formally showed BANFF cat. 4 IB. However, fluorescence in situ hybridization detected SARS-CoV-2 viruses in large portions of the distal tubules. After nine weeks of persistent COVID-19 disease neither anti-SARS-CoV-2 IgG nor a SARS-CoV-2-specific cellular immune response could be detected, leading to the administration of sotrovimab and remdesivir. Among them, SARS-CoV-2 clearance, detection of IgG, and improvement of graft function were achieved.ConclusionLack of viral clearance can lead to complications of SARS-CoV-2 infection with atypical manifestations. In kidney transplant patients, before initiating therapy, the differential diagnoses of “rejection” and “virus infection” should be weighed against each other in an interdisciplinary team of nephrologists, infectious diseases specialists and pathologists.

Clinical outcome of norovirus infection in renal transplant patients.

Transplant patients are at increased risk for developing severe norovirus (NoV) infections with secondary complications such as rejection episodes and acute transplant failure. This single-center retrospective study included all kidney transplant patients tested positive for NoV RNA between January 2007 and December 2011. Data were compared to a control group of 528 kidney transplant patients without NoV infection. Sixty-five kidney transplant patients were recorded NoV RNA positive. Of these, 26 patients (40%) presented with acute transplant failure (AKI). In 43 patients (66.2%), dose reduction in immunosuppression was performed, and of 22 patients receiving tacrolimus, four patients (18.2%) showed toxic trough levels above 15ng/mL at time of diagnosis. In three patients (4.6%), indicated therapeutic procedures had to be postponed due to prolonged severe diarrhea. Ten patients (15.4%) developed chronic NoV infection. One-year patient and graft survival in NoV patients and controls was 92.3% and 96.4%, respectively (n.s.). Compared to controls, eGFR was already significantly lower before NoV infection and loss of eGFR relative to baseline over 12 and 36months was significantly higher in NoV-infected patients. In particular, patients initially presenting with AKI experienced a long-term loss of transplant function. Risk factors for NoV infection were immunosuppression containing steroids and antirejection therapy.

Usefulness of combined continuous suture and interrupted tie technique in hindlimb composite tissue allotransplantation in rats

According to our experience of over 100 hindlimb transplantations, in rats, catching the posterior wall with an anterior wall suture is the most common cause of thrombosis and acute transplant failure. It is generally due to inadequate visibility of the lumen and consequent blind suture placement. With an intention to find a superior suture technique, a comparative study between standard end-to-end interrupted and combined continuous sutures and interrupted tie techniques was performed. Twenty hindlimb transplantations to rats' femoral vessels were performed in each group. Anastomosis time, patency, complications, and animal and transplant survivals were compared. In the interrupted suture group (group I), anastomosis failure was encountered in one vein, with 95% of immediate patency rate. A redo of the venous anastomosis was performed and successful. The combined suture technique (group II) had 100% patency rates without complications. The average time for arterial anastomosis in groups I and II was 8.5 and 8.9 min, and for venous anastomosis, 10.7 and 9.6 min, respectively. At 2 weeks, no differences were found between groups as related to transplant and animal survival.

Doppler and color Doppler imaging in acute transplant failure.

Most renal transplants are lost by rejection. A method is required to identify and discriminate between this and acute tubular necrosis and cyclosporin toxicity. The sonogram of the normal renal transplant is characteristic. Early Doppler studies measuring a rise in vascular impedance in acute rejection showed a high sensitivity and specificity. This appears, at least in part, to have been due to patient selection. We conclude that Doppler studies cannot be used to differentiate between the main parenchymal causes of renal transplant failure, although it can be helpful, with other clinical information, in supporting a diagnosis and in monitoring the effects of treatment.

Relationship between dialyzer reuse and the presence of anti-N-like antibodies in chronic hemodialysis patients

One hundred eleven chronic hemodialysis patients from five dialysis units were tested for the presence of antibodies reactive with red blood cell N substance; 77 patients were available for follow-up study after 18 to 24 months. Initially, 18 patients (16%) had serum anti-N-like antibodies. Thirteen of these patients were in a home dialysis program and were reusing hollow fiber dialyzers. The other five had practiced hollow fiber dialyzer reuse in the past. None of 37 patients using coil dialyzers had anti-N-like antibody. On follow-up testing, anti-N-like antibody persisted in all patients restudied except for one who had a successful renal transplant. Anti-N-like antibodies developed in four additional patients: three were reusing hollow fiber dialyzers at the time, but one had not reused dialyzers for 24 months. Statistical analyses indicated that dialyzer reuse, hollow fiber dialyzers, and home dialysis were significantly related to the presence of anti-N-like antibodies. We interpret the clinical and statistical data to indicate that dialyzer reuse is the major clinical factor in the development of anti-N-like antibody. The likely mechanism involves the prolonged exposure of red cells trapped in the dialyzer to formaldehyde used in preparing dialyzers for reuse. No adverse clinical effects of anti-N-like antibodies were evident in our patients, but hemolysis and acute transplant failure have been reported by others.