What is the approach to managing elevated Liver Function Tests (LFTs) before considering a FibroScan?

Management of Elevated Liver Function Tests Before FibroScan

Patients with elevated liver function tests (LFTs) should undergo a systematic evaluation to identify the underlying cause before proceeding with FibroScan, as persistent LFT abnormalities may indicate underlying liver disease requiring specific management approaches. 1

Initial Assessment of Elevated LFTs

Step 1: Confirm Persistent Elevation

• Repeat LFTs after 3-6 months to confirm persistence of abnormalities 1
• Perform testing during clinical stability (not during acute illness or antibiotic treatment) 1
• Use age and sex-normative values for interpretation 1

Step 2: Evaluate Pattern of LFT Abnormality

• Hepatocellular pattern: Predominant elevation of AST/ALT
• Cholestatic pattern: Predominant elevation of ALP/GGT
• Mixed pattern: Elevation of both transaminases and cholestatic enzymes 1

Step 3: Risk Stratification

• Calculate FIB-4 score: (Age × AST)/(Platelets × √ALT) 2
  • Low risk: <1.3 (<2.0 in those >65 years)
  • Indeterminate risk: 1.3-2.67
  • High risk: >2.67 2

Pre-FibroScan Evaluation

For Suspected NAFLD:

1. Assess metabolic risk factors (T2DM, BMI >25, dyslipidemia, hypertension) 1
2. First-line testing using FIB-4 or NAFLD Fibrosis Score 1
3. If FIB-4 >3.25, consider direct referral to specialist without FibroScan 1

For Suspected Alcohol-Related Liver Disease:

1. Assess alcohol consumption patterns using AUDIT-C screening tool 1
2. For women drinking >35 units/week or men drinking >50 units/week, proceed directly to FibroScan 1
3. For lower consumption but GGT >100 U/L, proceed to fibrosis assessment 1
4. Ensure at least 1 week of alcohol abstinence or reduced drinking before FibroScan if AST or GGT >2× upper limit of normal 1

Important Considerations Before FibroScan

Factors That May Affect FibroScan Results:

• Acute liver inflammation can falsely elevate readings 2
• Recent meals (fasting for 2-3 hours recommended) 2
• Severe steatosis may affect accuracy 2
• Obesity (BMI >28) is associated with higher failure rates of FibroScan measurement 3

Contraindications and Special Populations:

• Contrary to previous beliefs, cardiac pacemakers or implantable cardioverter-defibrillators are not contraindications for FibroScan 4
• For pediatric patients, assessment of fibrosis should be performed after referral to secondary care 1

When to Proceed with FibroScan

FibroScan should be performed after:

• Confirmation of persistent LFT elevation (>3-6 months) 1
• Completion of initial risk stratification with FIB-4 or other non-invasive tests 1
• Resolution of acute inflammation (if present) 1
• Period of alcohol abstinence (if applicable) 1

When to Refer to Specialist Before FibroScan

Consider direct referral to a hepatologist when:

• FIB-4 score >3.25 or NAFLD Fibrosis Score >0.675 1
• Evidence of advanced liver disease on imaging or blood tests 1
• Persistently elevated liver enzymes with negative extended liver aetiology screen and no risk factors for NAFLD 1
• BMI >28 (due to higher risk of FibroScan failure) 3

Common Pitfalls to Avoid

• Don't rely solely on LFTs: Normal liver blood tests do not rule out advanced fibrosis and cirrhosis 1
• Don't delay evaluation: Using high thresholds for abnormal LFTs can contribute to delayed diagnosis 1
• Don't perform FibroScan during acute inflammation: Wait for resolution of acute hepatic inflammation to avoid false elevations 1
• Don't ignore metabolic risk factors: Even with normal LFTs, patients with metabolic syndrome may have significant fibrosis 2
• Don't overlook alcohol consumption: There is a synergistic effect between alcohol intake and obesity on liver disease risk 1

By following this systematic approach to elevated LFTs before FibroScan, clinicians can ensure appropriate patient selection and timing for this non-invasive assessment of liver fibrosis, ultimately improving diagnostic accuracy and patient outcomes.