What are the next steps for a mother who reports having Human Immunodeficiency Virus (HIV) and a daughter being treated for HIV, but the mother's laboratory results show she is HIV negative, despite never having been treated for HIV?

Immediate Next Steps for Discordant HIV Status

The mother should be counseled that she is HIV-negative based on her laboratory results, and you must immediately investigate the daughter's HIV diagnosis to clarify this discrepancy, as a truly HIV-positive child born to an HIV-negative mother represents either a testing error, misunderstood results, or non-maternal transmission. 1

Critical First Actions

1. Verify the Mother's HIV Test Results

• Confirm that proper HIV testing algorithm was followed: screening EIA with confirmatory Western blot or IFA, as women with negative EIAs should be considered uninfected 2
• Consider repeat HIV antibody testing to exclude any laboratory error, particularly specimen-handling or mislabeling errors, which are the most common causes of incorrect HIV results 3
• If the mother has no identifiable HIV risk factors and negative confirmatory testing, she should be considered uninfected 1

2. Investigate the Daughter's HIV Diagnosis Urgently

• Obtain detailed documentation of the daughter's HIV testing, including:
  • Type of tests performed (antibody vs. nucleic acid amplification tests)
  • Age at testing (critical because maternal antibodies persist up to 18 months) 2
  • Confirmatory test results 2
• Contact the infectious disease specialist treating the daughter to review her diagnostic workup 2
• Request copies of all HIV test results for the daughter, as patients may misunderstand or misreport previous test results 2

Possible Explanations for This Discrepancy

Most Likely Scenarios:

Misunderstood or Incorrect Test Results:

• The mother may have misperceived that she is infected or misunderstood previous test results, which occurs uncommonly but is documented 2
• The daughter's diagnosis may be based on maternal antibody testing before 18 months of age rather than definitive HIV nucleic acid testing (PCR or viral culture), which is required for diagnosis in infants 2

Testing Errors:

• Specimen-handling errors, laboratory errors, or failure to follow recommended testing algorithms are the primary causes of incorrect HIV results 3
• Mislabeled samples must always be considered, especially when clinical presentation doesn't match results 3

Non-Maternal Transmission (if daughter truly infected):

• If the daughter is genuinely HIV-positive and mother is genuinely negative, consider alternative transmission routes (sexual abuse, contaminated blood products, or other exposures)

Rare but Important Consideration

Elite Controllers or Seroreversion:

• Extremely rarely, HIV-infected persons can have persistently negative EIA results even with AIDS and detectable viral loads, though this occurs with HIV-1 subtype B infection 4
• If clinical suspicion remains high despite negative antibody testing, consider HIV RNA viral load testing or p24 antigen testing 4
• However, the mother reports never being treated, making spontaneous viral clearance or elite controller status highly unlikely

Clinical Pitfalls to Avoid

• Never diagnose HIV based on screening tests alone—all positive results require confirmatory testing 3
• Do not assume the mother is lying or in denial—approach with empathy while systematically investigating the discrepancy 2
• Remember that a positive HIV test in a child under 18 months indicates infection in the mother only if proper diagnostic testing (not just antibody testing) was performed 2
• False-positive results when both screening AND confirmatory tests are reactive are extremely rare (approximately 1 in 135,000 in low-prevalence populations) 3

Documentation and Follow-Up

• Document the mother's negative HIV test results clearly in the medical record 2
• Schedule urgent follow-up after obtaining the daughter's complete HIV testing documentation 2
• If the daughter's HIV diagnosis is confirmed with appropriate testing and the mother remains negative, mandatory reporting to child protective services may be required to investigate potential non-maternal transmission routes
• Provide the mother with clear counseling about her negative status while explaining the need to investigate the discrepancy 1