Comparison of clinicopathological characteristics between pregnancy and non-pregnancy-related renal cortical necrosis

Objective To compare the clinicopathological characteristics between pregnancy-related and non-pregnancy-related renal cortical necrosis(RCN).Methods From January 2010 to May 2021, clinical data were reviewed retrospectively for 18 patients who were diagnosed as RCN at Peking University First Hospital.They were divided into two groups of pregnancy-related(n=14) and non-pregnancy-related(n=4).The inter-group differences in clinicopathalogical characteristics were compared.Results There were 14 cases in pregnancy-related group and 4 cases in non-pregnancy-related group.The most common causes of pregnancy-related RCN were postpartum hemorrhage(n=5) and eclampsia(n=5).Non-pregnancy-related causes included infection and thrombotic microangiopathy.Compared with that of non-pregnant group, diagnostic time of RCN was longer in pregnancy group(40.6 d vs 24.5 d), proportion of AKI was higher(100% vs 0), hemoglobin(78.2 g/L vs 142.3 g/L) and platelet(45.5×10⁹/L vs 195.5×10⁹/L) level were lower and lactic dehydrogenase level(2046.7 IU/L vs 219.3 IU/L) was higher.TMA features were found in 9 cases in pregnancy group and 1 case in non-pregnancy group.In pregnancy group, hemodialysis(n=13) and plasma exchange(n=12) were offered.However, none received these two treatments in non-pregnancy group.Three cases entered maintenance hemodialysis and 2 cases underwent kidney transplantation(KT) in pregnancy group.However, none received hemodialysis or KT in non-pregnancy group.Conclusion Compared to non-pregnancy-related RCN, pregnancy-related RCN has a more rapid onset and yet a delayed diagnosis and has more severe symptoms and significant renal ischemia.Its treatment often depends on blood purification technology and its prognosis remains poor.