[the early diagnosis of the vertical transmission of the human immunodeficiency virus type 1. The evaluation of diagnostic tests]. / Diagnóstico precoz de la transmisión vertical del virus de la inmunodeficiencia humana tipo 1. Valoración de las pruebas diagnósticas.

BACKGROUND: The early diagnosis of vertically transmitted human immunodeficiency virus infection cannot be based on the presence of specific serum antibodies since those of the maternal IgG class pass the placenta and may be detected in children for up to 18 months. Based on this fact, the aim of this study was to evaluate other techniques for early diagnosis of the infection applicable from birth in 306 children of infected mothers. METHODS: The production of in vitro antibodies, virus culture and polymerase chain reaction (PCR) were used. The sensitivity of the techniques was estimated in the 40 children diagnosed with human immunodeficiency virus infection and specificity was determined in the 266 uninfected children. RESULTS: The sensitivity for the production of in vitro antibodies was 62.0% at 3 months and 94.7% at 6 months; 90.4% and 88.2%, respectively, for the viral culture and 92.3% and 94.1%, respectively, for the PCR. The specificity of all the cases was higher than 89.4% although varied in relation to age. CONCLUSIONS: The combination of several diagnostic techniques provides better performance for the early diagnosis of vertical transmission of the human immunodeficiency virus. Given that viral culture takes longer to provide results and is more expensive, it is less recommendable for routine use, although the form of viral replication may be useful to establish the prognosis.

Prognostic value of immunological data, in vitro antibody production, and virus culture in vertical infection with HIV-1.

The prognostic value of immunological indices, in vitro antibody production, and virus culture pattern at 3 months of age was estimated in 35 infants infected by HIV-1 from a cohort of 298 babies born to HIV-1 seropositive mothers and followed up from birth. At 1 year old, 15 of these infants were classified as stage P-1 (according to the Centers for Disease Control classification) seven were P-2A, and seven had AIDS. Significantly higher CD8 percentages, lower percentages and absolute value of CD4, and lower CD4/CD8 ratios at 3 months were observed in infants with severe symptoms at 1 year of age when compared with those who were asymptomatic at this age. Seventy seven per cent of infants with a 'rapid' virus culture when 3 months old had developed AIDS or had died by 1 year of age and only 8% of those with 'slow' virus culture had AIDS when 1 year old. Moreover, 100% of those who were asymptomatic at 1 year had a slow virus culture at 3 months. Significant statistical association was found between the virus replication pattern at 3 months and the clinical stage at 1 year of age.

Immunological follow-up in children born to HIV-1 infected mothers.

From November 1985 to January 1990 we examined 156 children born to 154 HIV-1 seropositive mothers every 3 months. Eighty-seven infants were over 18 months by January 1990. Six of them met the CDC criteria of HIV-1 infection or died from AIDS; a transmission rate of 7%. Six of the children aged less than 18 months also met the CDC criteria of HIV-1 infection. These 12 infected children were compared with the 81 presumably unifected children. The perinatal findings were similar in both groups. Most of the HIV-1 infected babies showed early abnormalities in humoral and cellular immunity, hypergammaglobulinemia, low percentage of CD4 circulating lymphocytes and increased spontaneous in vitro immunoglobulin production. These changes were persistent in the HIV-1 infected children, but sporadic in those uninfected. Immunological abnormalities were frequently found before clinical symptoms appeared. We conclude that repeated immunological abnormalities in babies born to HIV-1 seropositive mothers are suggestive of HIV-1 infection.