Primary biliary cholangitis (PBC) is a chronic autoimmune disease characterized by progressive destruction of the small intrahepatic bile ducts, leading to cholestasis and potential progression to cirrhosis. Prognosis is favorable when diagnosed and treated early, while diagnostic delay is common. Diagnosis is based on elevated ALP and the presence of autoantibodies (AMA/ANA), but the disease is often asymptomatic and detected late.It predominantly affects women aged 40-60 years, and evidence suggests underdiagnosis, highlighting the need for screening strategies in at-risk populations.

Women will be consecutively enrolled during routine pre-hospitalization blood sampling for scheduled admissions at our University Hospital. In all participants, alkaline phosphatase (ALP) and gamma-glutamyl transpeptidase (GGT) will be measured on the same blood sample collected for standard clinical care.Patients with elevated ALP or GGT will undergo reflex testing for anti-mitochondrial antibodies (AMA) and anti-nuclear antibodies (ANA). Patients with positive AMA or ANA results will be informed and, if consenting, referred to a specialized gastroenterology and hepatology outpatient clinic for rare diseases.During this visit, based on reflex test results and clinical assessment, a diagnosis of primary biliary cholangitis (PBC) will be confirmed or further diagnostic evaluation will be performed if needed. Even if PBC is not confirmed, hepatology counseling and appropriate follow-up will be considered.

Inclusion Criteria:

• Female sex,
• age ≥ 40 years,
• patients attending the pre-hospitalization service for planned admission requiring the measurement of alkaline phosphatase (ALP) and gamma-glutamyl transpeptidase (GGT or gamma-GT) as part of routine clinical practice;
• the patient is able to understand the study information and provide informed consent.

Exclusion Criteria:

• Previous diagnosis of Primary Biliary Cholangitis (PBC) or other liver disease,
• patients unable to understand the study information and for whom informed consent cannot be obtained,
• patients with known conditions associated with elevated ALP: pregnancy, extrahepatic biliary obstruction (e.g., choledocholithiasis, biliary or pancreatic neoplasms), hepatic neoplasms or metastases, Paget's disease, bone neoplasms or metastases, hyperparathyroidism.