The Ursodeoxycholic Acid Response Score predicts pathological features in primary biliary cholangitis.

AIM: The ursodeoxycholic acid response score (URS) can predict the biochemical response to 12 months of ursodeoxycholic acid (UDCA) treatment in patients with primary biliary cholangitis (PBC). We investigated the relationship between the URS and the histopathological features before and after UDCA treatment.

METHODS: Patients with PBC (n=126) were examined for the association between the probability of response (POR) to UDCA based on the URS formulas and the clinicopathological features. Furthermore, 30 patients were examined for the association between the POR and pathological changes.

RESULTS: The POR area under the receiver operating characteristic curve (AUROC) for predicting the biochemical response to UDCA was 0.861. The PORs of stage 1 in the Nakanuma system and grade 0 in the CK7 grading in hepatocytes were significantly higher than those of stage 3 and grade 3, respectively. The AUROCs for the prediction of ≥stage 2, ≥stage 3, and stage 4 in the Nakanuma system at pretreatment were 0.592, 0.710, and 0.817, respectively. The AUROCs for the prediction of ≥grade 1, ≥grade 2, and grade 3 in the CK7 hepatocyte grading were 0.741, 0.824, and 0.970, respectively. Furthermore, the AUROC for predicting the histological stage progression after UDCA treatment in the Scheuer classification and the Nakanuma system were 0.712 and 0.799, respectively.

CONCLUSIONS: The URS not only predicts the biochemical response, but also reflects the Nakanuma system and the CK7 hepatocyte grading at pretreatment. This scoring system can identify an inadequate histological response to UDCA treatment in the Scheuer classification and the Nakanuma system.