Can vomiting cause transaminitis (elevated liver enzymes)?

Can Vomiting Cause Transaminitis?

Yes, vomiting can cause transaminitis, particularly in the context of hyperemesis gravidarum where abnormal liver enzymes occur in approximately 50% of cases, though elevations are rarely greater than 1,000 IU/L and typically resolve with hydration and cessation of vomiting. 1

Mechanism and Clinical Context

The most well-documented association between vomiting and transaminitis occurs in hyperemesis gravidarum, which affects 0.35% to 2.0% of pregnancies. 1 This condition is characterized by:

• Persistent vomiting with weight loss ≥5% of prepregnancy body weight 1
• Dehydration and ketonuria as key diagnostic features 1
• Elevated transaminases in ~50% of cases, with ALT typically greater than AST 1
• Rare elevations above 1,000 U/L 1
• Jaundice rarely occurs 1

Resolution Pattern and Management

The biochemical abnormalities typically resolve with hydration and resolution of vomiting, which is the critical diagnostic and therapeutic feature. 1 This reversibility distinguishes vomiting-induced transaminitis from other causes of liver injury.

Treatment approach includes:

• Rehydration and correction of electrolyte abnormalities 1
• Thiamine supplementation to prevent Wernicke's encephalopathy 1
• Anti-emetic therapy with ondansetron, metoclopramide, or promethazine 1
• Nutritional support 1

Critical Diagnostic Caveat

Persistent liver chemistry abnormalities despite symptom resolution should prompt investigation for another etiology. 1 This is the most important clinical pitfall to avoid—assuming all transaminitis in the setting of vomiting is benign and self-limited.

When liver biopsy is performed (rarely indicated), findings typically reveal:

• Normal parenchyma 1
• Mild fatty change 1
• Bland cholestasis 1

Differential Considerations in Pregnancy

When evaluating transaminitis with vomiting in pregnant patients, consider other pregnancy-specific liver diseases that can present with nausea/vomiting: 1

• HELLP syndrome: AST/ALT elevations with thrombocytopenia and hemolysis 1
• Acute fatty liver of pregnancy (AFLP): AST/ALT 300-1,000 U/L with jaundice and hypoglycemia 1
• Intrahepatic cholestasis of pregnancy (ICP): AST/ALT 2-30 times ULN with pruritus and elevated bile acids 1

Non-Pregnancy Context

While the evidence base is strongest for hyperemesis gravidarum, the principle that severe vomiting with dehydration can cause mild-to-moderate transaminitis applies more broadly. The mechanism likely involves:

• Hepatic hypoperfusion from dehydration and volume depletion
• Metabolic stress from starvation ketosis
• Electrolyte disturbances affecting hepatocyte function

Monitoring Recommendations

For patients with vomiting and transaminitis:

• Expect improvement within days of adequate hydration and anti-emetic therapy 1
• Recheck liver enzymes after symptom resolution to confirm normalization 1
• Pursue alternative diagnoses if transaminases remain elevated or worsen despite clinical improvement 1
• Avoid hepatotoxic medications during the acute phase, including acetaminophen at standard doses 2