human immunodeficiency virus-1 (HIV1) western blot

Indications

• HIV1

Clinical significance

a positive western blot is defined as the presence of bands for the following HIV proteins:

• p24
• gp41
• gp120
• gp160

CDC criteria:

• gp41 & (gp120 or gp160)
• p24 & (gp41 or gp120 or gp160)

MKSAP15 criteria: gp120 & (gp41 or p24)

An indeterminate western blot partially fulfills CDC criteria. 10-20% of HIV1 EIA positive specimens are indeterminate by western blot.

In the special case of infants who may carry maternal antibody, IgM antigen tests have been developed but lack sensitivity.

Methods

• Western blot.
• HIV proteins are run on a polyacrylamide gel.
• the patient's serum is used as a source of antibodies to HIV proteins; that is the test detects antibodies to specific HIV proteins
• the antibodies fix protein to the gel if present in the serum
• positive & negative controls are run with patient specimens

Specimen

• serum, plasma

More general terms

• HIV laboratory testing
• western blot

Additional terms

• electrophoresis
• human immunodeficiency virus-1 (HIV-1)

Component of

• HIV panel