From the Guidelines
Elevated liver enzymes in infectious mononucleosis are typically self-limiting and resolve spontaneously as the infection clears, usually within 3-6 weeks, and do not require specific treatment beyond supportive care. The elevation of liver enzymes, particularly transaminases (ALT and AST), is a common finding in infectious mononucleosis, occurring in approximately 80-90% of patients 1. This elevation may rise to 2-3 times the normal range, though occasionally can reach 5-10 times normal values. According to the acr appropriateness criteria® abnormal liver function tests, hepatocellular predominant abnormal liver function tests are reflected as an increase in aminotransferases, ALT, and AST, which is consistent with the liver enzyme abnormalities seen in infectious mononucleosis 1.
The severity of abnormal aminotransferase can be classified as mild, moderate, or severe, with moderate and severe being discussed collectively due to significant clinical overlap 1. In the context of infectious mononucleosis, the elevation of liver enzymes is usually mild to moderate. The liver enzyme elevation occurs because the Epstein-Barr virus (EBV) that causes mononucleosis directly infects liver cells and triggers an immune response, leading to mild hepatitis.
Management of infectious mononucleosis focuses on supportive care, including:
- Adequate hydration
- Rest
- Acetaminophen for fever and discomfort (using the lowest effective dose, typically 500-1000mg every 6 hours, not exceeding 4000mg daily)
- Avoidance of alcohol during the illness and recovery period as it may further stress the liver
- Caution with NSAIDs due to their potential hepatotoxicity. Regular monitoring of liver enzymes is generally unnecessary unless symptoms of severe hepatitis develop, such as jaundice, severe right upper quadrant pain, or significantly elevated bilirubin levels.
From the Research
Significance of Elevated Liver Enzymes in Infectious Mononucleosis
Elevated liver enzymes are a common finding in infectious mononucleosis, with studies indicating that:
- Alanine aminotransferase (ALT), aspartate aminotransferase (AST), and γ-glutamyl transferase (GGT) levels are significantly higher in patients with infectious mononucleosis compared to healthy controls 2
- The presence of elevated liver enzymes increases clinical suspicion for infectious mononucleosis, particularly in the setting of a negative heterophile antibody test result 3
- Elevated liver enzymes can be an atypical presentation of Epstein-Barr virus infectious mononucleosis, as seen in a case report of a 24-year-old male with cholestatic hepatitis and hyperbilirubinemia 4
Association between Liver Enzymes and Infectious Mononucleosis
Research suggests that there is a positive association between transferase levels and infectious mononucleosis, particularly in males, and a negative association between total bilirubin (TB) and infectious mononucleosis, particularly in females 2
- The risk of infectious mononucleosis is significantly increased in patients with high levels of transferases, with crude odds ratios (ORs) of 21.667 and 10.111 for males and females, respectively 2
- Low bilirubin levels are also suggestive of infectious mononucleosis, particularly in females, with crude ORs of 8.229 and 8.257 for males and females, respectively 2
Clinical Implications
The presence of elevated liver enzymes in infectious mononucleosis can have significant clinical implications, including:
- The need for comprehensive serological testing to confirm the diagnosis of Epstein-Barr virus infection 4, 3
- The importance of considering infectious mononucleosis in the differential diagnosis for young adults presenting with both infectious symptoms and abnormal liver function tests 4, 3
- The potential for rare renal and hematological complications, such as gross hematuria and hemolytic anemia, particularly in children 5