Absolute CD4+ T-lymphocyte count as a surrogate marker of pediatric human immunodeficiency virus disease progression.
BACKGROUND
Traditionally in pediatric HIV, the CD4+ T-lymphocyte percent is used to monitor disease progression because of the variability in absolute CD4+ T-lymphocyte numbers. Because of the high cost of equipment, sophisticated and delicate technology, most laboratories in resource-limited settings use simple protocols that enumerate only the absolute CD4+ T-lymphocyte counts. We assessed the use of absolute CD4+ T-lymphocyte count as a surrogate marker of pediatric HIV disease progression.


METHODS
We analyzed the CD4+ T-lymphocytes and HIV viral load over a 10-year period (1996-2006) of 97 HIV-infected children enrolled in the Yale Prospective Longitudinal Pediatric HIV Cohort using generalized linear mixed models. Both CD4+ T-lymphocytes and HIV viral load were assessed at baseline and every 2-3 months. The modeling approach used in this study allows the intercept and the rate at which outcome variables change over time to vary across participants.


RESULTS
We determined that absolute CD4+ T-lymphocytes count was just as reliable at monitoring pediatric HIV as CD4+ T-lymphocyte percentage. Antiretroviral treatment, regardless of the regimen used, was associated with higher CD+ T-lymphocytes count (P < 0.01). Race was significantly associated with CD4+ T-lymphocytes counts (with lower values for blacks compared with nonblacks; P < 0.01). The presence of other infections was associated with lower CD4+ T-lymphocyte count (P = 0.01) and higher viral load (P < 0.01), respectively.


CONCLUSIONS
In situations where determination of CD4+ T-lymphocyte percentages is not readily available, the absolute count may provide an affordable and accessible laboratory surrogate marker of HIV disease progression in children.
Paintsil
Elijah
E
Department of Pediatrics, Yale University School of Medicine, New Haven, CT 06520, USA. elijah.paintsil@yale.edu
Ghebremichael
Musie
M
Romano
Sostena
S
Andiman
Warren A
WA
D000293:Adolescent; D015415:Biomarkers; D018791:CD4 Lymphocyte Count; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D002648:Child; D002675:Child, Preschool; D018450:Disease Progression; D005260:Female; D006678:HIV; D015658:HIV Infections / Q000175:diagnosis* / Q000276:immunology*; D006801:Humans; D008137:Longitudinal Studies; D018655:Lymphocyte Count; D008297:Male; D019562:Viral Load
D015415:Biomarkers