Low gamma-glutamyl transpeptidase levels at presentation are associated with severity of liver illness and poor outcome in biliary atresia

ObjectiveTo investigate the clinical features and prognosis of biliary atresia (BA) with normal or minimally elevated gamma-glutamyl transpeptidase (GGT). MethodsThe clinical data of patients with BA in our hospital between 2012 and 2017 were retrospectively studied. The patients were divided into a low-GGT group (GGT <= 300 IU/L) and a high-GGT group (GGT > 300 IU/L) according to the preoperative GGT level. The perioperative clinical parameters, the postoperative jaundice clearance within 6 months, and the 2-year native liver survival were compared among the groups. ResultsA total of 1,998 children were included in this study, namely, 496 in the low-GGT group and 1,502 in the high-GGT group. The ages and weights at the surgery in the low-GGT group were significantly lower than those in the high-GGT group (64.71 +/- 21.35 vs. 68.64 +/- 22.42 days, P = 0.001; 4.67 +/- 1.03 vs. 4.89 +/- 0.98 kg, P < 0.001). The levels of serum ALP, ALT, and AST in the low-GGT group were significantly higher than those in the high-GGT group before and 2 weeks after the surgery (ALP: 647.52 +/- 244.10 vs. 594.14 +/- 228.33 U/L, P < 0.001; ALT: 119.62 +/- 97.14 vs. 96.01 +/- 66.28 U/L, P < 0.001; AST: 218.00 +/- 173.82 vs. 160.71 +/- 96.32 U/L; P < 0.001). The INR of the low-GGT group was higher than that of the high-GGT group (1.05 +/- 0.34 vs. 0.98 +/- 0.20, P < 0.001), while FIB was lower than the high-GGT group (2.54 +/- 0.67 vs. 2.73 +/- 1.44 g/L; P = 0.006). The decreasing amplitude of TB and DB within 2 weeks after surgery in the low-GGT group was smaller than those in the high-GGT group (TB: 51.62 +/- 71.22 vs. 61.67 +/- 53.99 mu mol/L, P = 0.003; DB: 33.22 +/- 35.57 vs. 40.20 +/- 35.93 mu mol/L, P < 0.001). The jaundice clearance rate in the low-GGT group was significantly lower than that in the high-GGT group at 1, 3, and 6 months after surgery (17.70 vs. 26.05%; 35.17 vs. 48.58%; 38.62 vs. 54.64%, P < 0.001). In addition, the 2-year native liver survival rate in the low-GGT group was significantly lower than that of the high-GGT group (52.5 vs. 66.3%, P < 0.001 HR 1.80, 95% CI 1.38-2.33). ConclusionCompared to patients with high GGT, patients with normal or minimally elevated pre-operative GGT in BA were found to have poorer pre-operative liver function parameters, and post-operatively had lower jaundice clearance rates and worse 2-year native liver survival. This suggests a lower GGT at presentation in biliary atresia could be a sign of more severe liver injury.