Abnormal LFTs inc Fib4 score

Information

This guidance has been developed specifically for use in primary care within NHS Borders. General practitioners may choose to use it when mildly abnormal LFTs results have been found in asymptomatic patients. It is hoped this will increase the efficiency of investigations for liver disease whilst avoiding unnecessary tests and referrals.

There are no meta-analyses or randomised controlled trials concerning the management of abnormal liver function tests in asymptomatic people. This guidance is therefore based on a combination of prospective, retrospective or cross-sectional clinical studies and expert opinion. It has been developed partly based on Forth Valley guidelines but through extensive collaboration with hepatologists, general practitioners and laboratory staff from NHS Lothian. It is not intended to serve as a rigid protocol or to replace clinical judgement.

 

INTRODUCTION

Abnormal liver function tests (LFTs) are very common in primary care. They are often found co-incidentally in patients without hepatobiliary symptoms. Such patients should be investigated if the abnormalities are significant and persistent because most liver disease is silent until advanced. Investigations should determine the aetiology and therefore the treatment to arrest or reverse the disease. Investigations should also stage the disease to detect those with advanced fibrosis or cirrhosis – still often clinically silent – who require further management in secondary care.

Most persistently abnormal LFTs will be due to alcohol, non-alcoholic fatty liver disease (NAFLD) or viral hepatitis. Other causes, although rare, are equally important to diagnose because nearly all are treatable.

 

CONTENTS

Please see below for further information:

• Isolated Rise in ALT
• Isolated Rise in GGT
• Isolated Rise in ALP
• Isolated Rise in Bilirubin
• Statins and Abnormal LFTs
• Drugs which may cause Abnormal LFTs
• Table of Abnormal LFTs and Clinical Clues

This guideline relates to investigating adults with asymptomatic abnormal liver blood tests.

Liver blood tests are frequently checked in primary care, and abnormal results are increasingly commonly encountered. Top causes include non-alcoholic fatty liver disease and alcohol. The purpose of investigating persistently abnormal liver blood tests is to diagnose any liver disease and to assess severity in terms of fibrosis stage. This is important to be able to offer disease-specific interventions and identify liver cirrhosis, or those at risk of progression to cirrhosis.

Investigation should be offered to all those likely to benefit from diagnosis and management. Progression of liver disease to cirrhosis occurs over years, and investigation of asymptomatic laboratory abnormalities may be less relevant in frail individuals with multiple comorbidities. A personalised approach with shared decision-making is therefore appropriate.

Asymptomatic ALT, GGT or ALP

Suggested thresholds for investigation where samples are checked on at least 2 occasions >4 weeks apart

• ALT > 50
• GGT > 100
• ALP > 175 (with raised GGT- consider bone disease if GGT not elevated) (Note ULN in Borders is 150)

Patient assessment

• History including alcohol intake and medications review
• Examination- palpate liver & spleen, spider nevi, palmar erythema, BMI
• Investigation

History

If alcohol intake is high consider advising abstinence and repeating LFTs

Hepatitis risks- Person who injects drugs, sexual history, travel history

Metabolic syndrome- T2DM, Obesity, BP

Autoimmune- T1DM, Rheumatoid arthritis, Thyroid disease

Family history

 

Medications review

Drugs known to be associated with drug induced liver injury usually cause a hepatitic picture with an increased ALT/AST or a cholestatic picture with an elevated ALP. Identifying the offending drug and stopping it is key to the management.

 

Type of reaction	Associated drugs
Hepatocellular pattern of DILI ALT (or AST) alone is increased ≥5-fold above ULN or a ratio of ≥5	Paracetamol, diclofenac, disulfiram, efavirenz, fenofibrate, isoniazid, lamotrigine, minocycline, nevirapine, nitrofurantoin, pyrazinamide, rifampicin and sulfonamide
Cholestatic pattern of DILI ALP alone is increased ≥2-fold above ULN or ratio ≤2	Co-amoxiclav, androgens, cephalosporins, chlorpromazine, erythromycin, flucloxacillin, oral contraceptives, penicillins, sulfonamide and terbinafine
Mixed pattern of DILI Ratio of >2 to <5	Carbamazepine, lamotrigine, phenytoin and sulfonamides
Autoimmune-like hepatitis Presenting features of acute or chronic DILI with serological and/or histological markers of idiopathic autoimmune hepatitis	Adalimumab, α-methyldopa, diclofenac, herbal supplements, infliximab, minocycline, nitrofurantoin and statins

 

Investigations

All patients should have full LFTs checked as well as a liver screen which includes:

FBC, U&E, LFTs, AST, Calcium/albumin, GGT, Glucose (of HbA1c if known diabetic), INR, Cholesterol, Immunoglobulins

Ferritin- if elevated then add iron studies

Serum ceruloplasmin- if patient <55

Hepatitis serology- Hepatitis B and C

Autoimmune liver screen- Anti-smooth muscle antibody, Anti-nuclear antibody, Anti-LKM1, Anti-mitochondrial antibody

 

Fib4 score

Should be used to aid referral decision and is calculated from the patient's blood tests and examination findings. There are multiple online tools to help calculate the Fib4 score.