Utility of total lymphocyte count as a surrogate marker for cd4 cell count in HIV infected children
Abstract
With the HIV pandemic and highly active antiretroviral therapy (HAART) expanding,there
is need to evaluate less expensive, more available and accessible bio- methods for
detecting level of immunosuppression. WHO guidelines recommend use of total lymphocyte
unt (TLC). CD4 and CD4% to depict level of immunosuppression. We therefore evaluated the
utilityof TLC as surrogate marker for CD4+ T cell count in HIV infected children in three
omprehensive Care Centres (CCCs) in Kenya; New Nyanza Provincial Hospital (NNPGH) in Kisumu Kenyatta
national Hospital (KNH) and Mbagathi District Hospital (MDH) in Nairobi
We carried out a hospital based retrospective study. Paired data on CD4+ T cell count
and TLC were collected from hospital records from HAART naive HIV infected children.
Data were categorized into < 12 months, 12 - 35 months. 36-59 months and >59 months age
strata.Spearman rho coefficient was used to establish correlation between TLC and CD4 and
TLC and CD4% pairs. The sensitivity, specificity. positive and negative predictive values of
various TLC cut offs was determined using the WHO CD4+ T cell cut-off values as the gold
standard.
Results
Four hundred and eighty seven HAART naive HIV infected children with a median
age of36 months (1-144 months) were enrolled into the study. 46% were females and 54%
were males. One hundred and twenty five children were enrolled from NNPGR 186 from
MDH and 176 from KNH.
Positive correlation was found between TLC and CD4+. Overall correlatiori for whole study
population was 0.66 (p<O.OO 1). This correlation varied by geographical region with highest
correlation in KNH (r=0.76, p<O.OOl), followed by MDH (r= 0.55. p<O.OOl), then NNPGH
(r= 0.54, p<O.OO1). It also varied by age with highest correlation coefficient in children above
59 months of age (r= 0.68, p<O.OO1), lowest in children less than 12 months of age (r=0.45.
p<O.OOI).The correlation also varied with severity of immuno suppression; higher in severely
immuno suppressed category (r= 0.72. p<O.OO1). lower in the non-severely immunosuppressed
(r-0.63, p<O.OOl).
Citation
Masters of medicine in Paediatrics,Sponsorhip
University of NairobiPublisher
Department of Paediatrics, College of Health Sciences, University of Nairobi, Kenya.