What investigation is most likely to establish the liver diagnosis?

A 56-year-old woman with hypertension was found to have abnormal liver function tests when she attended for routine review. She was taking bendroflumethiazide, ramipril and simvastatin.
On examination, her body mass index was 30 kg/m2 (18–25).
Investigations:
serum total bilirubin 15 µmol/L (1–22)
serum alanine aminotransferase 65 U/L (5–35)
serum aspartate aminotransferase 75 U/L (1–31)
serum alkaline phosphatase 305 U/L (45–105)
serum gamma glutamyl transferase 150 U/L (4–35)
What investigation is most likely to establish the liver diagnosis?

A: antimitochondrial antibodies
B: CT scan of abdomen
C: ferritin
D: MRCP
E: ultrasound scan of abdomen

Correct answer: A Explanation Antimitochondrial antibodies are present in over 90% of patients with primary biliary cirrhosis (PBC). The pattern of deranged liver function tests is cholestatic and likely indicates PBC. CT scan and MRCP are both unhelpful in diagnosing PBC as it mainly affects small bile ducts. Ferritin will be unhelpful as she is unlikely to have haemochromatosis. Ultrasound scan is indicated and helpful to exclude other associated abnormalities such as fatty liver. However, it is nonspecific and will not establish a diagnosis.