Problems in Diagnosis of HIV Infection in Babies

Serological diagnosis of human immunodeficiency virus (HIV) infection in babies born to HIV infected mothers is difficult because of presence of maternal anti-HIV antibody up to 18 months. Conventional enzyme-linked immunosorbent assay (ELISA) and western blot may be positive in un-infected cases. Various other modalities which have been adopted include detection of HIV specific IgA, IgM, IgE, detection of p24 antigen, viral culture and detection of HIV nucleic acid by polymerase chain reaction (PCR). Viral culture or PCR positivity within first 48 hours of life indicates intrauterine infection. An early diagnosis of HIV infection in babies born to HIV infected mothers is essential as definite antiretroviral therapy (ART) can be instituted and unnecessary toxicity of drug therapy avoided if found negative. Though viral culture and DNA-PCR has sensitivity of >95% after one month of age, some cases can not be diagnosed during this period. Other tests like viral RNA detection by reverse transcription polymerase chain reaction (RT-PCR) and combination of tests will be required.