HIV seronegativity in an infant with the acquired immunodeficiency syndrome.

We report the case of an infant with progressive human immunodeficiency virus (HIV) infection and persistent seronegativity. The child had Pneumocystis carinii pneumonia at 4 months of age and was documented to be HIV-infected by HIV-1 deoxyribonucleic acid (DNA) polymerase chain reaction (PCR), but enzyme-linked immunosorbent assay (ELISA) and Western blot tests for HIV-1 and HIV-2 specific antibodies remained negative until the infant was 10 months old. This case should increase awareness about the possibility of seronegative HIV infection in infants and stress the fact that in questionable cases, even if the screening serology is negative, additional methods of diagnosis (ie, PCR, viral culture, and p24 antigen) should be considered.