With the development of the single antigen beads assay, the role of donor specific alloantibody (DSA) against human leukocyte antigens in kidney transplantation (KT) has been highlighted. This study aimed to investigate the clinical significance of DQ-DSA detected at renal allograft biopsy. We evaluated 263 KT recipients who underwent allograft biopsy and DSA detection at the same time. Among them, 155 patients who were nonsensitized before transplantation were selected to investigate the role of de-novo DQ-DSA. Both the total and nonsensitized subgroup was categorized into 4 groups each according to DSA results as: DQ only, DQ + non-DQ, non-DQ, and no DSA. In the total patient group, post-KT DSA was positive in 79 (30.0%) patients and DQ-DSA was most prevalent (64.6%). In the nonsensitized subgroup, de-novo DSAs were detected in 45 (29.0%) patients and DQ-DSA was also most prevalent (73.3%). The DQ only group showed a significantly longer post-KT duration compared to the other groups (P < 0.05). The overall incidence of antibody-mediated rejection (AMR) was 17.9%. B-DSA, DR-DSA, and DQ-DSA were associated with AMR (P < 0.05), but in the analysis for chronic AMR, only DQ-DSA showed significance in both the total and the nonsensitized subgroup (P < 0.05). On comparison of Banff scores among groups, those representing humoral immunity were significantly dominant in all DSA positive groups compared to the no DSA group (P < 0.05), and higher scores of markers representing chronic tissue injury were more frequently detected in the groups with DQ-DSA. The worst postbiopsy survival was seen in the DQ + non-DQ group of the total patient group, and patients with de-novo DQ-DSA showed poorer graft survival in the nonsensitized subgroup compared to the no DSA group (P < 0.05). In the multivariate analysis, de-novo DQ-DSA was the only significant risk factor associated with late allograft failure (P < 0.05). Our study is the first to demonstrate the association of DQ-DSA with detailed histological findings representing chronic AMR. These findings suggest that the detection of DQ-DSA in nonsensitized patients is significantly associated with the development of chronic AMR and late allograft failure. Therefore monitoring of DQ-DSA not only in sensitized patients, but also nonsensitized patients may be necessary to improve long-term allograft outcomes.

We investigated whether HLA class II eplet mismatch was related to dnDSA development and analyzed its combined impact with tacrolimus levels for kidney transplantation outcomes. A total of 347 kidney transplants were included. HLA Matchmaker was used for the single molecular eplet, total eplet, antibody (Ab)-verified eplet mismatch analyses, and Ab-verified single molecular analysis to identify HLA-DR/DQ molecular thresholds for the risk of dnDSA development. A time-weighted tacrolimus trough level (TAC-C0) of 5 ng/mL and a TAC-C0 time-weighted coefficient variability (TWCV) of 20% were applied to find the combined effects on dnDSA development. A high level of mismatch for single molecular eplet (DQ ≥ 10), total eplet (DQ ≥ 12), Ab-verified eplet (DQ ≥ 4), and Ab-verified single molecular eplet (DQ ≥ 4) significantly correlated with HLA class II dnDSA development. Class II dnDSA developed mostly in patients with low TAC-C0 and high eplet mismatch. In the multivariable analyses, low TAC-C0 and high eplet mismatch showed the highest hazard ratio for the development of dnDSA. No significant combined effect was observed in dnDSA development according to TWCV. In conclusion, the determination of HLA class II eplet mismatch may improve the risk stratification for dnDSA development, especially in conjunction with tacrolimus trough levels.

Several studies reported the effect of obesity on the progression of IgA nephropathy (IgAN). However, the impact of obesity on the clinicopathologic presentation of IgAN remains uncertain. This is a retrospective cross-sectional study from eight university hospitals in South Korea. Patients were categorized into three groups using the Asia-Pacific obesity classification based on body mass index (BMI). Clinical and histopathologic data at the time of renal biopsy were analyzed. Among 537 patients with IgAN, the obese group was more hypertensive and had lower estimated glomerular filtration rate and more proteinuria than other groups. The histologic scores for mesangial matrix expansion (MME), interstitial fibrosis, tubular atrophy, and mesangial C3 deposition differed significantly between the three groups. Among these histopathologic parameters, BMI was independently positively associated with MME score on multivariable linear regression analysis (p = 0.028). Using multivariable logistic regression analysis, the obese group was independently associated with higher MME scores compared to the normal weight/overweight group (p = 0.020). However, BMI was not independently associated with estimated glomerular filtration rate or proteinuria on multivariable analysis. Obesity was independently associated with severe MME in patients with IgAN. Obesity may play an important pathogenetic role in mesangial lesions seen in IgAN.

Malnutrition is a common and serious complication in patients with chronic kidney disease (CKD), significantly impacting morbidity, mortality, and health-related quality of life. Recognizing the close association between nutritional status and clinical outcomes, recent clinical practice guidelines have emphasized proactive nutritional assessment and individualized intervention as key components of CKD management. Accurate nutritional assessment remains challenging in CKD patients due to fluid shifts, altered body composition, and laboratory variability. While various nutritional assessment tools are available, their interpretation requires careful consideration due to each tool’s characteristics and patient’s CKD stage. Nutritional interventions must be tailored to the patient’s CKD stage, dialysis status, and comorbidity profile. Strategies include individualized dietary counseling and oral nutritional supplements. Also, patient education and multidisciplinary collaboration—particularly involving nephrologists and renal dietitians—are essential to improving adherence and long-term outcomes. This review focuses on evaluating the nutritional status and intervention of CKD patients, highlighting key aspects based on the latest literature and clinical guidelines.

Haeun Lee, M.D., Hanbi Lee, M.D., Sang Hun Eum, M.D., Eun Jeong Ko, M.D., Ph.D., Ji-Won Min, M.D., Ph.D., Eun-Jee Oh, M.D., Ph.D., Chul Woo Yang, M.D., Ph.D., and Byung Ha Chung, M.D., Ph.D.. Ann Lab Med 2023;43:364-74. https://doi.org/10.3343/alm.2023.43.4.364

It is well known that pre-transplant B cell activating factor (BAFF) levels are associated with the development of de novo anti-HLA antibodies and antibody mediated rejection post-transplant. However, the clinical significance of BAFF values at allograft rejection has not been determined. In this study, we investigated the clinical significance of pre-transplant BAFF level as well as post-transplant BAFF levels measured when indication biopsy was done. We checked for anti-HLA antibodies in 115 kidney transplant recipients who required allograft biopsy due to an increase in serum creatinine. With the same serum specimen, we measured BAFF levels, and in 78 of these patients, pre-transplant BAFF and anti-HLA antibody levels were detected as well. Patients in each group were divided into tertiles according to BAFF levels. We investigated the relationship between BAFF levels and the occurrence of anti-HLA antibodies. Pre-transplant BAFF levels showed significant association with pre-transplant sensitization, and also with early rejection (Tertile 3, 26.9% vs. Tertile 1, 11.5%; P<0.05). Post-transplant BAFF levels showed significant association with pre-transplant sensitization, but did not show association with anti-HLA antibodies and positive donor-specific antibodies at the time of biopsy. We did not find any association between post-transplant BAFF levels and allograft biopsy results, Banff scores and microvascular inflammation scores. In conclusion, pre-transplant BAFF levels are associated with pre-transplant sensitization and are useful in predicting allograft rejection. But post-transplant BAFF levels measured at the time of indication biopsy are not associated with the appearance of de novo HLA-DSA, allograft rejection, biopsy findings and other allograft outcomes.