What are the recommended laboratory tests and imaging studies for a patient with suspected cirrhosis?

Laboratory Tests and Imaging for Suspected Cirrhosis

For patients with suspected cirrhosis, obtain a comprehensive hepatic function panel including bilirubin, AST, ALT, alkaline phosphatase, albumin, PT/INR, platelet count, complete blood count, and renal function tests, followed by abdominal ultrasound as the initial imaging modality. 1

Initial Laboratory Evaluation

Core Hepatic Function Panel

• Bilirubin (total and conjugated): Elevated conjugated bilirubin indicates advanced disease or biliary obstruction 1
• AST and ALT: Typically elevated in active liver injury, with AST/ALT ratio often >1 in cirrhosis 1
• Alkaline phosphatase: May be elevated, particularly in cholestatic liver disease 1
• GGT: Useful for detecting hepatobiliary involvement and calculating fibrosis indices 1
• Albumin: Decreased levels indicate impaired synthetic function and are part of Child-Pugh scoring 1
• PT/INR: Prolonged values indicate impaired hepatic synthetic function and are critical for Child-Pugh and MELD scoring 1

Additional Essential Tests

• Complete blood count with platelet count: Thrombocytopenia suggests portal hypertension and is a surrogate marker for advanced disease; platelet count is specifically important for calculating fibrosis indices like APRI and FIB-4 1
• Creatinine and BUN: Essential for MELD score calculation and detecting hepatorenal syndrome 1

Etiologic Workup

Once cirrhosis is suspected, determine the underlying cause with targeted testing:

• Hepatitis B panel and hepatitis C antibody: Confirm viral load in all positive cases to guide antiviral therapy 1
• Ferritin and transferrin saturation: Screen for hemochromatosis 1, 2
• Autoimmune markers: Consider if etiology is unclear 1
• Alpha-1 antitrypsin level: Screen for alpha-1 antitrypsin deficiency 1
• Ceruloplasmin: Consider for Wilson disease, particularly in younger patients 1

Initial Imaging Studies

Ultrasound as First-Line Imaging

Abdominal ultrasound is the recommended initial imaging modality for suspected cirrhosis. 3, 2

• Ultrasound has 65% to 95% sensitivity and 98% positive predictive value for detecting cirrhosis 3
• The most accurate sonographic finding is a nodular liver surface, which is more sensitive on the undersurface of the liver than the superior surface (86% versus 53%) 3
• Ultrasound confirms the absence of mechanical biliary obstruction with specificities ranging between 71% to 97% 3
• Standard ultrasonography should be performed as part of the initial workup 2

Advanced Imaging When Indicated

• Multiphasic CT or multiphasic MRI: Recommended when hepatocellular carcinoma is suspected, as both have similar diagnostic performance characteristics 3
• MRI with MRCP: May provide additional value if ultrasound is negative and clinical workup is inconclusive, particularly if there is concern for primary sclerosing cholangitis or primary biliary cirrhosis 3
• MR elastography: Can show changes of early fibrosis when there is questionable hepatic parenchymal disease based on laboratory findings 3

Non-Invasive Fibrosis Assessment

Calculate fibrosis indices using laboratory values already obtained:

• APRI (AST to platelet ratio index) 1, 2
• FIB-4 score 1, 2
• Transient elastography: Can rule out advanced fibrosis if liver stiffness is <6.4 kPa; cirrhosis is typically confirmed at levels ≥15 kPa 3, 4

These non-invasive tests are most useful in identifying patients with no to minimal fibrosis or advanced fibrosis 2

Ascites-Specific Testing (If Present)

When ascites is detected on imaging or physical examination:

• Diagnostic paracentesis should be performed immediately upon hospital admission in all cirrhotic patients with ascites, even without symptoms of infection 5
• Ascitic fluid cell count with differential: Diagnosis of spontaneous bacterial peritonitis requires PMN count >250/mm³ 5
• Ascitic fluid total protein 1
• Serum-ascites albumin gradient (SAAG) 1
• Ascitic fluid culture: Obtain at least 10 mL and inoculate blood culture bottles at bedside 5
• Additional tests based on clinical suspicion: Cytology, amylase, BNP, and adenosine deaminase 1

Critical Clinical Pitfalls to Avoid

• Do not wait for liver enzymes to reach >1.5-2× upper limit of normal before investigating; use age and sex-normative values, as delayed diagnosis can occur with high thresholds 1
• Persistent abnormalities over 3-6 months warrant further evaluation even if mildly elevated 1
• Perform screening during clinical stability to avoid misinterpreting transient elevations 1
• Never delay diagnostic paracentesis to rule out spontaneous bacterial peritonitis in patients with ascites on hospital admission 1
• Liver biopsy is not required for diagnosis when noninvasive testing is conclusive, but should be considered when results are indeterminate, etiology remains unknown, or when results may alter management 6, 7

Ongoing Monitoring Schedule

For patients with established cirrhosis:

• Perform Child-Pugh score components, MELD score components, and albumin-bilirubin grade every 6 months 1
• Patients with decompensated cirrhosis or active complications require liver function tests every 1-3 months 1
• Hepatocellular carcinoma screening with ultrasound every 6 months for all patients with cirrhosis 3, 2