CD4 count testing

Clinical description

• About 30% of PLHIV have a CD4 count <200 cells/ml at the time of starting ART and are

therefore at high risk of TB, CM and other HIV-related diseases.

• Do routine CD4 count for all adults and children 5+ years before/when staring ART if CD4

testing is available at the site. However, do not delay ART initiation if CD4 machine is down / results are delayed or testing is currently not available.

• Do Targeted CD4 count for patients with suspected clinical and/or confirmed treatment failure

(VL).

o CD4 <200 cells/ml: Do routine urine LAM and serum CrAg for all adults and children 5 years and above (see section 8.1 on page 22).

o CD4 200+ cells/ml: no specific action

• Use point-of-care (POC) machines or semi-quantitative rapid CD4 count test kits.
• CD4 counts are the most direct routine measure for HIV immune suppression, but can be

influenced by several factors:

o Gender, time of day, physical exercise, pregnancy, smoking, etc.

• Types of CD4 testing recommended in Malawi are:

o PIMA CD4 analyser: POC test from a finger prick or venous whole-blood sample.

o VISITECT CD4 semi-quantitative test: lateral flow rapid test that shows if the CD4 count is above or below 200 cells/ml; will be prioritised for sites that do not have PIMA CD4 analyser.

• CD4 counts using PIMA CD4 analyser may fail or give wrong results unless the following

protocol is used:

o Collect a minimum of 2ml venous blood in tube with EDTA anticoagulant.

o Immediately turn the tube upside down to mix the blood with EDTA. Do not shake vigorously o The sample must be processed in the lab within 6 hours or 48 hours, depending on the type of machine used.

o Storing the tube at 2-8° C in the dark will extend the lifespan by a few hours o Protect the tube from hard vibrations during transport.