Guidelines on the management of abnormal liver blood tests

Abstract

These updated guidelines on the management of abnormal liver blood tests have been commissioned by the Clinical Services and Standards Committee (CSSC) of the British Society of Gastroenterology (BSG) under the auspices of the liver section of the BSG. The original guidelines, which this document supersedes, were written in 2000 and have undergone extensive revision by members of the Guidelines Development Group (GDG). The GDG comprises representatives from patient/carer groups (British Liver Trust, Liver4life, PBC Foundation and PSC Support), elected members of the BSG liver section (including representatives from Scotland and Wales), British Association for the Study of the Liver (BASL), Specialist Advisory Committee in Clinical Biochemistry/Royal College of Pathology and Association for Clinical Biochemistry, British Society of Paediatric Gastroenterology, Hepatology and Nutrition (BSPGHAN), Public Health England (implementation and screening), Royal College of General Practice, British Society of Gastrointestinal and Abdominal Radiologists (BSGAR) and Society of Acute Medicine. The quality of evidence and grading of recommendations was appraised using the AGREE II tool. These guidelines deal specifically with the management of abnormal liver blood tests in children and adults in both primary and secondary care under the following subheadings: (1) What constitutes an abnormal liver blood test? (2) What constitutes a standard liver blood test panel? (3) When should liver blood tests be checked? (4) Does the extent and duration of abnormal liver blood tests determine subsequent investigation? (5) Response to abnormal liver blood tests. They are not designed to deal with the management of the underlying liver disease.

Keywords: alcoholic liver disease; fibrosis; liver; nonalcoholic steatohepatitis.

Figure 1

Response to abnormal liver blood tests. This figure details the initial response to abnormal liver blood tests. Boxes in yellow indicate the initial evaluation of the clinical presentation. Patients with marked derangement of liver blood tests, synthetic failure and/or suspicious clinical symptoms/signs should be considered for urgent referral to secondary care (red box). For the remainder, a clinical history alongside evaluation of the pattern of liver blood test derangement will determine choice of pathway and is shown in the grey boxes. A grey box indicates all the tests that should be requested at that stage rather than a hierarchy within it. The presence of metabolic syndrome criteria should be sought to support a diagnosis of NAFLD. For children, the text should be consulted for modification of recommendation. Areas of diagnostic uncertainty are indicated in orange boxes and the decision for repeat testing or referral to secondary care will be influenced by the magnitude of enzyme elevation and clinical context. Green boxes indicate final/definitive outcomes for users of the pathway. *Abnormal USS may well include extrahepatic biliary obstruction due to malignancy, which should result in urgent referral. ALP, alkaline phosphatase; ALT, alanine aminotransferase; ARLD, alcohol-related liver disease; AST, aspartate aminotransferase; BMI, body mass index; FBC, full blood count; GGT, γ-glutamyltransferase; INR, international normalised ratio; LDH, lactate dehydrogenase; NAFLD, non-alcoholic fatty liver disease; T2DM, type 2 diabetes mellitus; USS, ultrasound scan.

Figure 2

Non-alcoholic fatty liver fibrosis algorithm. For those patients with NAFLD or liver disease of unknown aetiology, the next step is to determine the likelihood of liver fibrosis. Initial assessment includes calculation of a FIB4 or NAFLD fibrosis score with values <1.3 and ≤1.455, respectively, signifying a low risk of advanced fibrosis. Higher cut-off points, <2.0 and <0.12, should be used for patients aged over 65 years. Second-line tests that should be considered include serum markers such as ELF and imaging modalities such as ARFI elastography/FibroScan. For children, the text should be consulted for modification of recommendation. Cut-off points for ARFI vary according to manufacturer and thus should be tailored to the device used. ARFI, acoustic radiation force impulse; ELF, enhanced liver fibrosis; FIB-4, fibrosis-4; HCC, hepatocellular carcinoma; NAFLD, non-alcoholic fatty liver disease; NFS, NAFLD Fibrosis Score.

Figure 3

Alcohol-related liver disease algorithm. In patients in whom alcohol is suspected to be the main injurious factor, the extent of consumption influences early decision-making. For those drinking at harmful levels, ≥35 units/week women and ≥50 units/week men, an assessment of liver fibrosis is the critical next step. For other patients, administration of the AUDIT C questionnaire alongside brief intervention is recommended initially. For patients who continue to drink at hazardous levels consideration should be given to assessment as for the higher-risk category according to liver fibrosis evaluation. This is particularly important for those with a GGT of >100 U/L. Cut-off points for ARFI vary according to manufacturer and thus should be tailored to the device used. ARFI, acoustic radiation force impulse; ELF, enhanced liver fibrosis; GGT, γ-glutamyltransferase; HCC, hepatocellular carcinoma.