LTR real‐time PCR for HIV‐1 DNA quantitation in blood cells for early diagnosis in infants born to seropositive mothers treated in HAART area (ANRS CO 01)

HIV‐1 diagnosis in babies born to seropositive mothers is one of the challenges of HIV epidemics in children. A simple, rapid protocol was developed for quantifying HIV‐1 DNA in whole blood samples and was used in the ANRS French pediatric cohort in conditions of prevention of mother‐to‐child transmission. A quantitative HIV‐1 DNA protocol (LTR real‐time PCR) requiring small blood volumes was developed. First, analytical reproducibility was evaluated on 172 samples. Results obtained on blood cell pellets and Ficoll‐Hypaque separated mononuclear cells were compared in 48 adult HIV‐1 samples. Second, the protocol was applied to HIV‐1 diagnosis in infants in parallel with plasma HIV‐RNA quantitation. This prospective study was performed in children born between May 2005 and April 2007 included in the ANRS cohort. The assay showed good reproducibility. The 95% detection cut‐off value was 6 copies/PCR, that is, 40 copies/10⁶ leukocytes. HIV‐DNA levels in whole blood were highly correlated with those obtained after Ficoll‐Hypaque separation (r = 0.900, P < 0.0001). A total of 3,002 specimens from 1,135 infants were tested. The specificity of HIV‐DNA and HIV‐RNA assays was 100%. HIV‐1 infection was diagnosed in nine infants before age 60 days. HIV‐DNA levels were low, underlining the need for sensitive assays when highly active antiretroviral therapy (HAART) has been given. The performances of this HIV‐DNA assay showed that it is adapted to early diagnosis in children. The results were equivalent to those of HIV‐RNA assay. HIV‐DNA may be used even in masked primary infection in newborns whose mothers have received HAART. J. Med. Virol. 81:217–223, 2009. © 2008 Wiley‐Liss, Inc.