Abnormal LFTs in Adults

Abnormal LFTs

Liver disease is often asymptomatic

Deranged LFTs may be the only sign of a serious underlying liver disease

Or they may be nothing wrong!

HyperbilirubinaemiaSlight increases in bilirubin (17-30 µmol/L) common &

usually not clinically significant.Checking conj/unconj (direct/indirect) bilirubin is seldom

required in adults, unless isolated raised bilirubin (i.e. normal liver enzymes)

Causes of isolated hyperbilirubinaemiaUnconjugated Conjugated

Gilbert’s syndrome (usually < 70 µmol/L)

Drugs e.g. phenothiazines, sulfonamides and carbimazole

Stress/fasting Dubin-Johnson syndrome

Drugs e.g. rifampicin, sulfonamides

Rotor syndrome

Haemolytic disease

Hyperbilirubinaemia

Transaminases (ALT, AST) ALT: mostly liver specific AST: expressed in liver cells, skeletal muscle, kidneys, brain,

RBCs

ALT <120iu/L: generally considered mild; >120iu/L: severe AST:ALT ratio > 2.1 may be suggestive alcohol related liver

disease AST:ALT ratio < 2.1 may suggest hepatic steatosis or chronic viral

hepatitis

Causes of raised transaminases:

Common Rarer Non-hepatic

Alcohol Autoimmune hepatitis Coeliac disease

Steatosis Haemachromatosis Strenuous exercise

Viral Hepatitis Alpha-1-antitrypsin defic

Muscle disease

Medications/toxins Wilson’s disease Endocrine (e.g. hypo/hyperthyroid

Raised ALT

Alkaline PhosphataseThe two main sources of ALP are liver and bone, although

there are also intestinal and placental isoforms.Causes of raised ALP:

Physiological Pathological

Third trimester of pregnancy Bile duct obstruction

Adolescents, due to bone growth

Primary biliary cirrhosis

Benign, familial Primary sclerosing cholangitis

Drug induced cholestasis, e.g. anabolic steroids, COCP

Metastatic liver disease

Bone disease, e.g. Pagets

Heart failure

Gamma Glutamyl Transferase (gGT)γGT : v sensitive marker for hepatobiliary disease,

but its use is limited by poor specificity.(Causes include hepatobiliary disease (often with other liver enzyme abnormalities), pancreatic disease, alcohol, COPD, Renal failure, Diabetes, IHD, Drugs, e.g. carbamazepine, phenytoin and barbiturates and oral contraceptive pill)

Main role of gGT is to support a hepatobiliary source for other liver enzymes

If isolated raised γGT: rpt bloods after 3m if <5x ULN; consider USS if >5x ULN;

Raised ALP

Deranged LFTs - historyPMH: diabetes, hyperlipidaemia, obesity, autoimmune

conditionsMedicationsAlcohol ConsumptionOccupational exposure to toxinsFamily history of liver disease, autoimmune conditionsRisk factors for viral hepatitis:

intravenous drug usetravel historynon-sterile ear or body piercingtattooshealth care intervention in developing nationscountry of birth

Liver screenLiver Ultrasound ASTγGTImmunoglobulins CKFerritinTFTsFasting LipidsGlucose / HbA1cCoeliac Serology Hepatitis serology (HBsAg, anti-HCV Abs) Liver Autoantibodies Alpha-1-antitrypsinCaeruloplasmin (if < 50y)