New guidelines to improve the use of liver blood tests
New recommendations, led by experts at the University of Birmingham, have been published to improve the use of liver blood tests.
The recommendations, published in Gut, are aimed at helping healthcare workers diagnose patients with liver disease as well as preventing unnecessary repeat tests for people unlikely to have the significant liver disease.
Major Recommendations :
- Initial investigation in patients with potential liver disease should include bilirubin, albumin, ALT, alkaline phosphatase (ALP) and gamma-glutamyltransferase (GGT) plus a complete blood count.
- Abnormal liver blood test results should only be interpreted after review of the previous results, past medical history and current medical condition. (level 5, grade D)
- The extent of liver blood test abnormality is not necessarily a guide to clinical significance. This is determined by the specific analyte which is abnormal (outside the reference range) and the clinical context. (level 5, grade D)
- Patients with abnormal liver blood tests should be considered for investigation with a liver aetiology screen irrespective of level and duration of abnormality. Abnormal refers to an analyte which is outside the laboratory reference range (level 2b, grade B)
- In adults a standard liver aetiology screen should include abdominal ultrasound scan (USS), hepatitis B surface antigen, hepatitis C antibody (with follow-on polymerase chain reaction (PCR) if positive), anti-mitochondrial antibody, anti-smooth muscle antibody, antinuclear antibody, serum immunoglobulins, simultaneous serum ferritin and transferrin saturation. (level 2b, grade C)
- In children, ferritin and transferrin saturation may not be indicated, but autoantibody panel should include anti-liver kidney microsomal antibody and coeliac antibodies. Alpha-1-antitrypsin level and caeruloplasmin (age >3 years) should be included, and abnormalities discussed with an appropriate inherited metabolic disease specialist. (level 2b, grade C)
- Adults with NAFLD should undergo risk stratification to determine the extent of their liver fibrosis.
First-line testing should use either fibrosis-4 (FIB-4) or NAFLD Fibrosis Score (NFS) – see table 3 (level 2b, grade B). Calculation facilities for FIB-4 and NFS should be incorporated in all primary care computer systems. (level 5, grade D)
Second-line testing requires a quantitative assessment of fibrosis with tests such as serum enhanced liver fibrosis (ELF) measurements or Fibroscan/acoustic radiation force impulse (ARFI) elastography. (level 2b, grade B)
We recommend that hepatologists at a local level champion this idea and discuss it with commissioners of health to deal with the burden of liver disease in their area.
- Consider referral to alcohol services for all adults with alcohol-related liver disease (ARLD) with evidence of alcohol dependency as defined by an AUDIT score of >19. (level 3b, grade C)
Harmful drinkers should undergo risk stratification with clinical assessment and Fibroscan/ARFI elastography. Adults should be referred to secondary care if there is evidence of advanced liver disease (features of cirrhosis or portal hypertension on imaging or from blood tests) and/or Fibroscan reading is >16 kPa (if available). (level 2b, grade B)
Adults with abnormal liver blood tests, even with a negative extended liver aetiology screen and no risk factors for NAFLD, should be referred/discussed to a gastroenterologist with an interest in liver disease/hepatologist for further evaluation . (level 4, grade C)
The recommendations now supersede earlier guidelines in 2000 and were commissioned by the Clinical Services and Standards Committee of the British Society of Gastroenterology.