If repeated ALT < 80 IU/L

Repeat LFTS after a further 3 months

• if normal then no further action is indicated
• if ALT > 120 IU/L then refer
  
  
• if ALT not resolving
  • repeat LFTs after further 3 months with further blood tests and liver ultrasound:

First line blood tests (2):

• serology for hepatitis B and C
• serum iron and total iron binding capacity: increased iron load suggests haemochromatosis
• serum caeruloplasmin levels: decreased levels suggest Wilson's disease
• serum protein electrophoresis:
  • increase polyclonal immunoglobulin suggests autoimmune hepatitis
  • decreased alpha-globulin suggests alpha-1 antitrypsin deficiency
• liver autoimmune serology (especially if female)
  
  

Consider second line blood tests (2):

• the following investigations should be performed in a patient with asymptomatic elevation of aminotransferase levels who remains undiagnosed despite first-line investigations:
  • alpha-1 antitrypsin phenotyping: a ZZ phenotype is diagnostic of a deficiency state
  • antigliadin and antiendomysial serology: presence indicates coeliac disease
  • creatine kinase and aldolase: elevation indicates muscle disease

• if blood tests normal then no further action is required
  • if ALT > 80 refer
  • if ALT raised but < 80 IU/L then repeat LFTs at 12 months to ensure that not rising

Reference:

1. Pulse (2004); 64 (30):34-6.
2. Pratt DS, Kaplan MM. Evaluation of abnormal liver-enzyme results in asymptomatic patients. NEJM 2000;342:1266-71