Hacke, Katrin

ABSTRACT HLA‐C*07:1268 differs from HLA‐C*07:02:01:01 by one nucleotide substitution in exon 3.

ABSTRACT HLA‐B*08:345Q differs from HLA‐B*08:238 by one nucleotide substitution, introducing a premature stop codon in exon 5.

ABSTRACT HLA‐A*32:202 differs from HLA‐A*32:01:01:01 by two nucleotide substitutions in exons 1 and 2.

ABSTRACT HLA‐DQB1*06:144N differs from HLA‐DQB1*06:03:01:01 by one nucleotide substitution, introducing a premature stop codon in exon 2.

ABSTRACT HLA‐B*57:205 differs from HLA‐B*57:01:01:01 by one nucleotide substitution in Exon 1.

ABSTRACT HLA‐A*24:675 differs from HLA‐A*24:02:01:01 by one nucleotide substitution in exon 3.

ABSTRACT HLA‐DQB1*06:549 differs from HLA‐DQB1*06:02:01:01 by one nucleotide substitution in exon 2.

ABSTRACT HLA‐C*03:737 differs from HLA‐C*03:05:01:01 by one nucleotide substitution in exon 3.

ABSTRACTThis single‐center retrospective study investigated subclinical rejection prevalence and significance in simultaneous pancreas and kidney transplant (SPKT) recipients. We analyzed 352 SPKT recipients from July 2003 to April 2022. Our protocol included pancreas allograft surveillance biopsies at 1, 4, and 12months post‐transplant. After excluding 153 patients unable to undergo pancreas biopsy, our study cohort comprised 199 recipients. Among the 199 patients with protocol pancreas biopsies, 107 had multiple protocol pancreas biopsies in the first year, totaling 323. Subclinical rejection was identified in 132 episodes (41%). Of these, 72% were Grade 1, 20% were indeterminate, and 8% were Banff Grade 2 or higher. All episodes of subclinical rejection were treated. Rates of pancreas graft loss (10% vs. 7%) and clinical rejection (21% vs. 20%) at 3 years were similar between those with and without subclinical rejection. Subclinical rejection Banff Grade 2 or more was associated with poor pancreas graft survival HR of 5.5 (95% CI: 1.24–24.37, p = 0.025). Of 236 simultaneous protocol kidney and pancreas biopsies, 102 (43%) showed pancreas subclinical rejection, while only 17% had concurrent kidney subclinical rejection. Our findings suggest limited predictive value of pancreatic enzymes and euglycemia in detecting pancreas rejection. Furthermore, poor concordance existed between pancreas and kidney subclinical rejection.

The value of the crossmatch test in assessing pretransplant immunological risk is vital for clinical decisions, ranging from the indication of the transplant to the guidance of induction protocols and treatment with immunosuppressants. The crossmatch tests in transplantation can be physical or virtual, each with its advantages and limitations. Currently, the virtual crossmatch stands out for its sensitivity and specificity compared to the physical tests. Additionally, the virtual crossmatch can be performed in less time, allowing for a reduction in cold ischemia time. It shows a good correlation with the results of physical tests and does not negatively impact graft survival. Proper communication between clinicians and the transplant immunology laboratory will lead to a deeper understanding of each patient’s immunological profile, better donor–recipient selection, and improved graft survival.