Anti retroviral therapy: CD4 reference range for Indians to help in better treatment modalities

Syed Akbar
Hyderabad: Anti retroviral therapy for HIV positive people in
the country will get a boost and doctors can now effectively monitor
the progression or otherwise of HIV in an individual, thanks to the
National AIDS Research Institute coming out with the reference range
for CD4 or immune cells for Indians.

CD4 cells provide immunity against diseases and a drastic drop in
their number points to an immunodeficiency problem in the body. They
also tell doctors how healthy an individual is, and whether or not a
person is HIV positive, and if so, has it progressed to AIDS. Once a
person is diagnosed as HIV positive, doctors will decide on anti
retroviral therapy (ART) based on the CD4 count.

There is no reference range for CD4 cells for the Indian population so
far and doctors have been initiating ART when the CD4 count drops
below 250 per microlitre. In the US and other developed nations, ART
begins when the CD4 count drops below 350 per microlitre.

The CD4 count differs from population to population and a reference
range for Indians will help in proper monitoring of the progression or
otherwise of HIV. The reference range also gains significance in the
backdrop of the Central government planning to begin ART regimen when
the CD4 count drops below 350, instead of the present 250. HIV
progresses into AIDS when the CD4 count falls below 200 per microlitre.

The National AIDS Research Institute in association with several other
research institutions across the country took up a study to arrive at
the reference range for CD4 count for Indians. According to the
research team, the reference range for absolute CD4 count for Indian
male population is 381-1565 cells per microlitre and for female
population 447-1846 cells per microlitre. The reference range for CD4
percentage is 25-49 for male and 27-54 for female population. Thus
far, doctors have been following the reference range of general
population (world average) of 500 to 2000 per microlitre.

The new reference range will help in diagnosis of immunodeficiency
disorders, evaluation of immune-mediated diseases, and assessment of
immune reconstitution following stem cell transplantation, besides
monitoring of disease progression or success of ART in HIV infection.
The Indian values of CD4 counts are comparable to the values reported
from Caucasian, British, Dutch populations and Thai populations.