Age and Serum Creatinine Can Differentiate Wilson Disease Patients with Pseudonormal Ceruloplasmin

Abstract

Background and Aim. Significantly reduced serum ceruloplasmin (Cp) is the most important clue in the diagnosis of Wilson’s disease (WD) and is well known to clinicians. The false increase in Cp in some WD patients, which overlaps with that in non-WD liver disease patients, decreases the diagnostic accuracy. The aims of our study were to understand the factors associated with Cp normalisation in WD patients and identify these WD patients using usual predictors. Methods. We retrospectively screened individuals with serum Cp ≥ 140 mg/L from 1032 WD patients who were hospitalised for the first time. Logistic regression analyses were performed in a case-control study between the WD cohort and another liver disease cohort to explore the independent risk factors for WD diagnosis and establish a regression model to identify them. The follow-up medical records of the WD cohort were subjected to mixed-effects model analysis in a longitudinal study to discover factors associated with Cp normalisation. Results. Eighty-six WD patients and their 353 medical records and another 98 non-WD liver disease patients were included in the present study. Cp normalisation was significantly associated with the copper burden and liver function indexes, such as urinary copper, γ-glutamyltransferase, and albumin ( $p\le 0.001$ ). Logistic regression analysis showed that age and serum creatinine ( $p\le 0.001$ ) were independent risk factors associated with WD. The AUC value of the regression model in the total cohort was 0.926 ( $p\le 0.001$ ). At a cutoff value of ≥0.617 and ≥−1, the positive and negative predictive values were both 90.8% for WD. Conclusion. Increased serum Cp in WD patients is related to excessive copper burden and hepatic injury, and common tests can effectively distinguish WD patients from other liver injury patients.