ABO blood type is associated with renal outcomes in patients with IgA nephropathy

// Meng Yang 1 , Jingyuan Xie 1 , Yan Ouyang 1 , Xiaoyan Zhang 1 , Manman Shi 1 , Xiao Li 1 , Zhaohui Wang 1 , Pingyan Shen 1 , Hong Ren 1 , Wen Zhang 1 , Weiming Wang 1 and Nan Chen 1 1 Department of Nephrology, Institute of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China Correspondence to: Nan Chen, email: // Jingyuan Xie, email: // Keywords : IgA nephropathy, ABO blood group, renal progression, end-stage renal disease, clinical follow-up, Immunology and Microbiology Section, Immune response, Immunity Received : July 18, 2017 Accepted : August 06, 2017 Published : September 07, 2017 Abstract ABO blood group antigens have been reported to be associated with inflammation and infections which have been largely implicated in the onset and progression of immune-mediated diseases. This study aimed to evaluate the association between ABO blood group and progression of IgA nephropathy (IgAN). We retrospectively enrolled 919 biopsy-proven IgAN patients with a minimum follow-up of 1 year and eGFR≥15ml/min/1.73m 2 at the time of renal biopsy. Patients in non-B antigen group (type O/A) had lower baseline eGFR, higher systolic blood pressure (SBP), uric acid, lactate dehydrogenase, high-sensitive C-reactive protein and tumor necrosis factor-α compared to patients in B antigen group(type B/AB). After a median follow-up of 57.46 months, 124(13.5%) patients progressed to end-stage renal disease (ESRD) including 98(17.7%) in non-B antigen group and 26(7.1%) in B antigen group. Kaplan-Meier analysis showed the median ESRD-free survival time of patients in non-B antigen group was significantly shorter than patients in B antigen group [143.09±6.38 vs 159.05±4.94months, p < 0.001]. Furthermore, non-B antigen blood group was associated with an independently increased risk of ESRD (HR=2.21, 95%CI 1.35-3.62, p = 0.002) after fully adjusted by age, sex, SBP, eGFR, blood urea nitrogen, hypoalbuminemia, uric acid, triglycerides, hemoglobin, serum C3, urine protein, Oxford classification and glucocorticoid treatment. In conclusion, our study suggests that ABO blood type is a new risk factor for IgAN progression. IgAN patients with blood type O or A have an independent increased risk for renal function deterioration which might be explained by an increased level of inflammatory status.