What are the next steps for a patient with a positive Hepatitis A (Hep A) antibody test?

From the Guidelines

If you have tested positive for Hepatitis A antibodies, the next steps depend on which type of antibody was detected, with IgM indicating current or recent infection and IgG showing past infection or vaccination, meaning you have immunity and no further action is needed. The presence of Hepatitis A antibodies, specifically IgG, indicates that the individual has developed immunity to the virus, either through past infection or vaccination 1. This is because IgG anti-HAV, which appears early in the course of infection, remains detectable for the person's lifetime and provides lifelong protection against the disease.

Key Considerations

• If IgM antibodies were found, this indicates a current or recent infection, and the individual should rest, stay hydrated, avoid alcohol, and follow up with their healthcare provider for monitoring liver function.
• If IgG antibodies were detected, this shows past infection or vaccination, meaning the individual has immunity and no further action is needed.
• No specific medication is required for Hepatitis A as it typically resolves on its own within a few weeks to months.
• However, if symptoms are severe (extreme fatigue, dark urine, jaundice, abdominal pain), the individual should seek medical attention.

Prevention of Transmission

• Those with positive IgM should avoid preparing food for others and practice good hand hygiene to prevent transmission.
• The virus spreads through contaminated food/water or close contact with infected individuals, and once recovered, the individual will have lifelong immunity against future Hepatitis A infections.

It's also important to note that individuals with chronic liver disease, such as those coinfected with HIV and HCV, should be vaccinated against hepatitis A to prevent fulminant hepatitis 1. However, in the case of a positive Hepatitis A antibody test, vaccination is not necessary if the individual already has immunity.

From the Research

Hepatitis A Antibody Positive: Next Steps

• A positive result for hepatitis A virus (HAV) immunoglobulin M (IgM) antibody indicates recent or current infection with HAV 2.
• However, most positive test results are associated with outpatient visits and are ordered in the assessment of patients with liver disease, but not clinical acute hepatitis 2.
• The presence of HAV antibodies can also indicate past infection or vaccination, and the level of antibodies can vary depending on the individual and the type of test used 3, 4.

Interpretation of Test Results

• The interpretation of serological testing for the diagnosis of acute hepatitis A infection can be challenging, especially in cases with low-level positive anti-HAV IgM results 4.
• A study found that all confirmed cases of acute HAV infection had anti-HAV IgM > 4.0, and a diagnosis other than acute HA was identified in 7/11 (63.6%) of low-level reactive anti-HAV IgM results 4.
• An interpretive algorithm is proposed, including a clinically significant cut-off value for anti-HAV IgM, to improve the accuracy of reports sent to clinicians 4.

Vaccination and Immunization

• Hepatitis A vaccination is recommended for all HIV-positive/HAV seronegative persons, with 2 standard doses given 6 to 12 months apart 5.
• The combined hepatitis A and B vaccine has been shown to be immunogenic, effective, and safe, with anti-HAV seropositivity rates ranging from 96.2% to 100% and anti-HBs seroprotection rates from 82% to 100% 6.
• The vaccine offers satisfactory long-term immunogenicity rates, expected duration of protection, and a safety profile similar to the monovalent hepatitis A or B vaccines 6.