Nonalcoholic fatty liver disease is having excessive fat (in the form of triglycerides) accumulation not due to excessive alcohol consumption or other secondary causes.

It is considered as a hepatic manifestation of metabolic syndrome.

Progression of nonalcoholic fatty liver disease is variable.


  • Patient with persistent abnormal liver enzymes, with insulin resistance &/or metabolic syndrome risk factors should be screened for nonalcoholic fatty liver disease (NAFLD)
  • Criteria for diagnosing non-alcoholic fatty liver disease:
    • Presence of steatosis in either imaging or histology studies
    • Alcoholic liver disease has been ruled out (daily alcohol consumption did not exceed 30 g for men & 20 g for women)
    • Other liver diseases (eg chronic hepatitis B/C, autoimmune liver disease) & metabolic or hereditary liver diseases have been ruled out


 Clinical Entities

  • Nonalcoholic Fatty Liver (NAFL)
    • Benign, nonprogressive entity
  • Nonalcoholic steatohepatitis (NASH)
    • Can progress to cirrhosis or even hepatocellular carcinoma


  • Patients are usually asymptomatic until the condition progresses to liver cirrhosis
  • Sometimes have vague symptoms of fatigue, malaise, & abdominal discomfort
  • Detailed patient history of alcohol consumption should be sought
  • Dietary & physical activity habits should be assessed because these influence the development & progression of nonalcoholic fatty liver disease (NAFLD)

Physical Examination

  • Physical findings to (rule out other causes of liver disease) assess progressive liver disease are presence of spider angiomas, acites, hepatomegaly, splenomegaly, palmar erythema, jaundice, hepatic encephalopathy

Laboratory Tests

  • Shows mild elevation of transaminases (ALT, AST)
  • Levels of serum transaminases are helpful in screening for nonalcoholic fatty liver disease (NAFLD) but these do not identify severity of NAFLD
  • Hepatitis B surface antigen, hepatitis C virus antibody or HCV-RNA should be done to exclude viral hepatitis as the cause of the fatty liver findings without chronic alcohol intake
  • Other findings include elevated hyaluronic acid that indicates fibrosis & low platelet counts with evidence of liver dysfunction such as elevated serum bilirubin & ammonia indicative of cirrhosis
Liver Biopsy
  • Diagnostic procedure considered in patients who are at increased risk to have nonalcoholic steatohepatitis (NASH) & advanced fibrosis or are suspected of having coexisting chronic liver diseases where there is a need to distinguish NASH from other chronic liver diseases
  • Essential in diagnosing & staging NASH


  • Nonalcoholic fatty liver disease (NAFLD) is characterized by macrovesicular steatosis in 5% of hepatocytes
  • Histologically NAFL is characterized by hepatic steatosis with no evidence of hepatocellular injury or no ballooning degeneration
  • Nonalcoholic steatohepatitis (NASH) is characterized histologically by hepatic steatosis associated with evidence of liver cell injury (ballooning degeneration) & lobular inflammation


  • Used to detect fatty changes
  • Abdominal ultrasound is the most common method of assessing hepatic steatosis
    • Preferred diagnostic procedure for nonalcoholic fatty liver disease (NAFLD) as it provides additional hepatobiliary information aside from presence of steatosis
  • Computed tomography & magnetic resonance imaging (MRI) seem to be more objective & more sensitive techniques for the quantification of steatosis, but MRI is still less widely available & much more expensive

Screening For Alcohol Abuse or Dependency

  • Patient’s alcohol consumption should be established to diagnose nonalcoholic fatty liver disease
    • Threshold is <20g/day in women, <30g/day in men
  • To evaluate the alcohol consumption of the patient, appropriate specialized questionnaires or scoring systems should be used
  • Tool most often used to assess alcohol dependency is “CAGE” questionnaire which refers to lifetime occurrence of the following:
    • Cutting down on drinking
    • Annoyance at others’ concerns about drinking
    • Feeling Guilty about drinking
    • Use of alcohol as an Eye opener in the morning
  • CAGE confirms clinically relevant alcohol consumption if at least one of the above questions is answered positively & if the Alcohol Use Disorders Identification Test (AUDIT) score is higher than 8
  • Other screening tools include the Michigan Alcoholism Screening Test (MAST) & the Lifetime Drinking History

Evaluation of Steatosis

Validated Steatosis Scores
  • Used in large scale screening for presence of steatosis
  • Nonalcoholic fatty liver disease fibrosis score is a widely validated scoring system for predicting the severity of fibrosis
    • It is based on 6 readily assessable clinical variables that include age, body mass index (BMI), hyperglycemia, platelet count, albumin & the aspartate transaminase/alanine transaminase ratio that is calculated using a published formula
  • Enhanced liver fibrosis (ELF) test is used to determine the presence of liver fibrosis
    • ELF score of ≥10.51 with nonalcoholic fatty liver disease indicates advanced liver fibrosis
    • Can also be used to test if pharmacological therapy is effective
  • Other scoring systems are Fatty Liver Index (FLI), SteatoTest & nonalcoholic fatty liver disease liver fat score
Digital Edition
Asia's trusted medical magazine for healthcare professionals. Get your MIMS Gastroenterology - Malaysia digital copy today!
Editor's Recommendations
Most Read Articles
Elvira Manzano, 5 days ago
Bisphosphonates have proven antifracture efficacy and remain to be the cornerstone of osteoporosis treatment. However, a drug holiday is of particular importance with bisphosphonates due to some signals with long-term use of the drug, including rare incidence of atypical femoral fracture (AFF) and osteonecrosis of the jaw (ONJ), says a leading endocrinologist at AFOS 2017.
Breast cancer patients have notably different microbiomes in the local breast tissue and urinary tract, a recent study reveals. Particularly, species in the Methylobacterium genus are reduced in the local breast tissue while the urinary tract is enriched in gram-positive bacteria.
Tristan Manalac, 2 days ago
Statin use, particularly in smokers, obese patients and nondiabetics, has a strong and dose-dependent association with decreasing risk of pancreatic ductal adenocarcinoma (PDAC), according to a new study.
15 Oct 2017
Second eye cataract surgery provides greater improvement in visual function and quality of life compared with first eye cataract surgery alone, a recent study claims.