Clinical Characteristics and Prognosis of Biliary Atresia with Low Serum Matrix Metalloproteinase-7 Levels

Serum matrix metalloproteinase-7 (MMP-7) levels can precisely differentiate biliary atresia (BA) from non-BA cholestasis. However, serum MMP-7 levels of some BA patients were within normal range or slightly elevated. This study aimed to investigate the clinical characteristics and prognosis of biliary atresia with low serum MMP-7 levels. This is a retrospective cohort study. Cases of BA from July 2020 to December 2022 were consecutively enrolled. They were divided into low-MMP-7 group (MMP-7 ≤ 25 ng/ml) and high-MMP-7 group (MMP-7 > 25 ng/ml) according to serum MMP-7 levels preoperatively. The perioperative clinical characteristics, the 3-month and 6-month jaundice clearance rate post-Kasai procedure, and the native liver survival were compared between the two groups. A total of 329 cases were included in this study, 40 of which were divided into the low-MMP-7 group. Preoperative GGT and direct bilirubin levels in the low-MMP-7 group were significantly lower than those in the high-MMP-7 group (258.6 U/L, interquartile range [IQR]: 160.4411.6 vs. 406.8 IU/L, IQR: 215,655.0, P = 0.0076; 103.8 μmol/L, IQR: 79.0,121.4 vs. 115.3 μmol/L, IQR: 94,138.8, P = 0.0071), while the gender, the day at surgery and preoperative ALT, AST, TBA, total bilirubin levels showed no significant differences (P > 0.05). The 3-month and 6-month jaundice clearance rate post-Kasai procedure in the low-MMP-7 group were lower than those in the high-MMP-7 group (29.73% vs. 53.09%, P = 0.049; 32.14% vs. 54.73%, P = 0.023). The 1-year native liver survival rate was 29.63% for the low-MMP-7 group and 53.02% for the high-MMP-7 group (P = 0.022). Preoperative clinical characteristics were similar between low-MMP-7 group and high-MMP-7 group, while patients with low serum MMP-7 levels showed worse prognosis, indicating that this might be listed as a new clinical subtype of BA which could contribute to designing new treatment strategies for BA in the future. Cohort Study. Level II.