To systematically analyze the expression of thrombospondin type 1 domain-containing 7A (THSD7A) and its diagnostic significance in membranous nephropathy (MN).

Both Chinese and English literatures were systematically searched included in Wanfang Med Online, China National Knowledge Infrastructure (CNKI), China Biomedical Literature Database, and PubMed. Meanwhile, references of the included literatures were also retrieved manually. Meta-analysis of the expression of THSD7A in MN patients was made with the R software and RevMan 5.3 software. The positive rates of THSD7A expression detected with serological and histological methods were compared. And the positive rates of THSD7A expression in MN, idiopathic MN (IMN), and secondary MN (SMN) patients were also compared. The prevalence of malignant tumors in the patients with THSD7A-associated MN was analyzed. Subgroup analysis was made according to the ethnicity of the patients with positive expression of THSD7A.

A total of 11 articles were included with a total of 4826 MN patients. The funnel plot was symmetrically distributed. The positive rates of THSD7A expression detected by both serological and histological methods in 5 of the 11 studies were compared, with the difference of positive rates being not statistically significant (OR=0.88, 95%CI: 0.62-1.25, P=0.48). The positive rate of THSD7A was 2.76% (95%CI: 2.33%-3.28%) in MN, 2.94% (95%CI: 2.19%-3.94%) in IMN, and 2.60% (95%CI: 1.29%-5.27%) in SMN. The subgroup analysis showed that the prevalence of THSD7A-associated MN was 2.49% (95%CI: 1.75%-3.54%) in the yellow race, and 2.85% (95%CI: 2.35%-3.47%) in the Caucasians, the difference of which was not statistically significant (I²=55.5%, P=0.13). The prevalence of malignant tumors in the patients with THSD7A-associated MN was 9.19% (95%CI: 4.68%-15.00%).

There was no significant difference in the positive rate of THSD7A expression between the serology and histology methods. THSD7A was an indicator of both IMN and SMN, and its positive rate was not significantly different between different races. The prevalence of malignant tumors in the patients with THSD7A-associated MN was 9.19%.