What are the first pass labs for a patient suspected of having cirrhosis?

First Pass Laboratory Tests for Suspected Cirrhosis

The first pass laboratory tests for a patient suspected of having cirrhosis should include a complete blood count, comprehensive metabolic panel, coagulation studies (PT/INR), viral hepatitis serologies, iron studies, and serum albumin. 1, 2, 3, 4

Core Laboratory Tests

Essential Initial Tests

• Complete blood count (CBC)

  • Evaluates for thrombocytopenia (marker of portal hypertension)
  • Assesses for anemia and leukocytosis/leukopenia 2

• Comprehensive metabolic panel

  • Liver function tests (AST, ALT, alkaline phosphatase)
  • Bilirubin (total and direct)
  • Albumin (synthetic liver function)
  • Electrolytes and renal function 2, 4

• Coagulation studies

  • PT/INR (reflects synthetic liver function) 2
  • Important for assessing severity and prognosis

Etiology-Specific Tests

• Viral hepatitis serologies

  • HBsAg, HBsAb, HBcAb (hepatitis B)
  • HCV antibody (hepatitis C) 3

• Iron studies

  • Ferritin
  • Transferrin saturation (to evaluate for hemochromatosis) 3

• Serum-ascites albumin gradient (SAAG)

  • If ascites is present, diagnostic paracentesis should be performed
  • SAAG ≥1.1 g/dL indicates portal hypertension with 97% accuracy 1
  • Total ascitic fluid protein should be measured (levels <15 g/L increase risk of spontaneous bacterial peritonitis) 1

Additional Tests Based on Clinical Context

• For suspected autoimmune etiology:

  • Immunoglobulin levels (especially IgG)
  • Autoantibodies (ANA, ASMA, anti-LKM) 1

• For suspected metabolic causes:

  • Alpha-1 antitrypsin level
  • Ceruloplasmin (Wilson's disease)

• For suspected NAFLD/NASH:

  • Lipid panel
  • Hemoglobin A1c
  • HOMA-IR (insulin resistance assessment) 1

Non-Invasive Fibrosis Assessment

• Fibrosis scoring systems:
  • AST to Platelet Ratio Index (APRI)
  • Fibrosis-4 (FIB-4) score
  • NAFLD fibrosis score (if NAFLD suspected) 3, 4

Imaging

While not laboratory tests, imaging should be considered part of first-pass evaluation:

• Abdominal ultrasound
  • Evaluates liver morphology, nodularity, and splenomegaly
  • Screens for ascites and portal hypertension 3

Monitoring Recommendations

Once cirrhosis is diagnosed, the American Association for the Study of Liver Diseases recommends:

• Laboratory monitoring every 3-6 months (CBC, comprehensive metabolic panel, PT/INR)
• Ultrasound surveillance for hepatocellular carcinoma every 6 months 2, 4

Common Pitfalls to Avoid

• Relying solely on liver enzymes - Normal liver enzymes do not exclude cirrhosis 2
• Overreliance on PT/INR for bleeding risk - These tests do not accurately predict bleeding risk in cirrhosis 2
• Failure to assess for portal hypertension - A key determinant of prognosis and complications 2
• Inadequate surveillance - Only 29.7% of patients with cirrhosis receive appropriate laboratory monitoring and only 8.8% receive proper HCC surveillance 5

Remember that early cirrhosis may be reversible with appropriate management of the underlying cause, making prompt and thorough evaluation crucial 3.