868 Impact of Neonatal Prophylaxis on Early HIV Diagnosis in Newborns
M. Burgard*1, S. Blanche1, M. J. Mayaux2, N. Ciraru3, C. Floch4, E. Lachassine5, J. M. Retbi6, C. Rouzioux1, the French Perinatal HIV Transmission Study Group7 1CHU Necker, Paris, France; 2CHU Bicetre, Paris, France; 3CHU Lariboisiere, Paris, France; 4Hosp Louis Mourier, Colombes, France; 5Hosp Jean Verdier, Bondy, France; 6Hosp de Saint Denis, France; and 7Agence Natl de Res sur le SIDA, Paris, France
Background: HIV DNA and HIV RNA have been reported by many groups as reliable methods for diagnosis of HIV infection in the neonatal period with 100% sensitivity after 1-2 months (mos) of age in absence of any preventive treatment. Here, we report our experience of HIV diagnosis in 63 infected neonates born from 1994 to 2002, in the context of mono or dual therapy for prevention of mother to child transmission (2,900 diagnosis were performed during the same period of time).
Methods: PBMC HIV DNA PCR and plasma HIV RNA PCR were tested on 40 samples taken at birth (day 0-7) and on 56 samples taken at one month of age (±2 wks). Mothers of infants tested at birth received ZDV (n = 26) or dual or triple therapy (n = 14). Infants tested at 1 month of age received at the time of sampling ZDV (n = 49), dual or triple therapy (n = 7). HIV DNA PCR was performed on PBMC, using either in house technique in the LTR gene or the HIV DNA Roche method. Plasma HIV RNA (RNA) was quantified by Monitor 1.5 Roche with limit of detection 50 copies/ml when possible (80%).
Results: Sixty percent (60%) of samples taken at birth were positive (pos) by HIV DNA and/or HIV RNA (independently of mother therapy). Results were concordant between both methods for 37 neonates and discordant for 3 (mother receiving ZDV or dual therapy) with pos HIV DNA alone (n = 1), or pos HIV RNA alone (n = 2). 4 of the 24 samples pos HIV RNA were < 400 copies/ml. On samples taken at 1 mo of age (e.g., during the treatment period of the neonates) HIV DNA was positive in 89% and HIV RNA in 86%; 84% were pos and 9% were neg by both tests. Discrepant results were obtained in 4 cases with pos HIV DNA, neg HIV RNA (n = 3) or neg HIV DNA, pos HIV RNA (n = 1). Plasma HIV RNA was lower in infants receiving dual or triple therapy (median 2,9 log/ml) than in infants receiving ZDV (median 4,8 log, MannWhitney, p = 0,02). Nine (9) of 9 infants with neg or discordant results had samples taken out of treatment period (2-3 mos of age). All had pos HIV DNA and a high HIV RNA (median 5,5 log).
Conclusions: At birth, diagnosis of HIV infection can be made for 60% of infected neonates. At 1 mo of age, during the period of prophylactic therapy, diagnosis is difficult for 16% of infected infants. HIV can replicate at low levels especially in case of dual therapy. The association of HIV DNA and HIV RNA tests is more confident. Lastly,100% diagnosis can only be obtained on samples taken after the treatment period.
