HCV RNA in blood donors with isolated reactivities by third-generation RIBA.
BACKGROUND
The objective of this collaborative study was to learn the proportion of HCV RNA-positive samples obtained from a population of donors with isolated anti-HCV reactivities by third-generation RIBA (RIBA-3) (indeterminate results).


METHODS
During a 2-year period, 11 blood transfusion centers kept all samples with indeterminate RIBA-3 results to test them by PCR, using both local and commercial techniques.


RESULTS
Of the 758 RIBA-3 indeterminate samples, 10 (1.3%) were positive for HCV RNA: 3. 3 percent (6/180) and 1.3 percent (4/317) of samples with anti-core or anti-NS3 reactivity, respectively, and none of the 52 and 209 samples with anti-NS4 or anti-NS5 reactivity, respectively. HCV RNA-positive donors with anti-core reactivity were infected with different subtypes (1 with HCV subtype 1b, 1 with 2, 1 with 2a/2c, 2 with 3a, and 1 with 5a), and a follow-up indicated a chronic-carrier state in two of the six donors. Acute hepatitis was diagnosed in three of the four donors with anti-NS3 reactivity alone. Two of these three were IV drug users and were infected with subtype 1a.


CONCLUSIONS
HCV RNA-positive donors with indeterminate results in RIBA-3 are extremely rare, but they do exist. They were observed only when either anti-core or anti-NS3 was present. With such a RIBA-3 profile, PCR testing remains necessary to reveal an eventual acute or chronic HCV infection.
Lemaire
J M
JM
Establishments of Blood Transfusion of Languedoc-Roussillon, Montpellier, France. lab.-imv@etslr.com
Courouce
A M
AM
Defer
C
C
Bouchardeau
F
F
Coste
J
J
Agulles
O
O
Cantaloube
J F
JF
Barlet
V
V
Barin
F
F
D000293:Adolescent; D000328:Adult; D001782:Blood Donors; D005260:Female; D016174:Hepacivirus / Q000276:immunology / Q000302:isolation & purification*; D006801:Humans; D015151:Immunoblotting / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012367:RNA, Viral / Q000032:analysis; D012680:Sensitivity and Specificity
D012367:RNA, Viral