Diagnostic inflammatory markers of acute cholangitis in liver transplant recipients.

Background: Acute cholangitis (AC) after liver transplantation occurs in 8-12% patients and remains a significant cause of patients' morbidity and mortality. The 2018 Tokyo guidelines use white blood cell count and C-reactive protein (CRP) as diagnostic criteria in AC. However, these and other common inflammatory markers have not been assessed in immunosuppressed liver transplant (LT) recipients with AC. The aims of this study were to compare the discriminative powers of common inflammatory markers, define the best inflammatory marker and determine the diagnostic cut-off values for the inflammatory markers in LT recipients with AC.

Methods: This was a retrospective cohort study. Over 16 years 212 LT recipients who underwent endoscopic biliary decompression were identified from hospital records. Thirty LT recipients with AC and 30 LT recipients without AC were randomly drawn in a 1:1 ratio.

Results: Among inflammatory markers, CRP had the highest discriminative power for diagnosing AC. The areas under the receiver operating characteristics curves for CRP, white blood cell count, lymphocyte count and neutrophil-to-lymphocyte ratio were 95% (95% confidence interval (CI): 91-98), 59% (95% CI: 50-68), 65% (95% CI: 53-77) and 70% (95% CI: 59-80), respectively. The cut-off value of CRP for diagnosing AC was equal to or above 9.5 mg/L.

Conclusion: CRP has the best discriminative power compared with other commonly used inflammatory markers for diagnosing AC in LT recipients. The optimal cut-off value for CRP concentration in diagnosing AC is equal to or above 9.5 mg/L.