Indeterminate human immunodeficiency virus type 1 western blots: seroconversion risk, specificity of supplemental tests, and an algorithm for evaluation.
The human immunodeficiency virus type 1 (HIV-1) Western blot is indeterminate in 10%-20% of sera reactive by EIA. Eighty-nine individuals with prior repeatedly reactive EIA and indeterminate Western blots were followed prospectively to study the risk of seroconversion and specificity of supplemental tests. Four high-risk cases seroconverted within 10 months after enrollment (seroconversion risk, 4.5%, 95% confidence interval, 1.2%-11.1%). Among cases with p24 bands initially, 4 (18.2%) of 22 high-risk individuals seroconverted compared with 0 of 33 low-risk cases (P = .03). Specificities of HIV-1 culture, serum p24 antigen, polymerase chain reaction, and recombinant ENV 9 EIA were 100%, 100%, 98.6%, and 94.4%, respectively. An expedited evaluation protocol is proposed. Low-risk individuals with nonreactive EIAs upon repeat testing do not need further follow-up; high-risk individuals should be followed serologically for at least 6 months, especially those with p24 bands on Western blot.
Celum
C L
CL
Department of Medicine, University of Washington, Seattle.
Coombs
R W
RW
Lafferty
W
W
Inui
T S
TS
Louie
P H
PH
Gates
C A
CA
McCreedy
B J
BJ
Egan
R
R
Grove
T
T
Alexander
S
S
D015492:AIDS Serodiagnosis; D000293:Adolescent; D000328:Adult; D000368:Aged; D001727:Bisexuality; D015153:Blotting, Western; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D015483:HIV Antibodies / Q000097:blood*; D006679:HIV Seropositivity; D015497:HIV-1 / Q000276:immunology*; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D011237:Predictive Value of Tests; D011446:Prospective Studies; D015531:Radioimmunoprecipitation Assay; D012307:Risk Factors; D012747:Sexual Partners
D015483:HIV Antibodies