M. Jadoul et al., INCIDENCE AND RISK-FACTORS FOR HEPATITIS-C SEROCONVERSION IN HEMODIALYSIS - A PROSPECTIVE-STUDY, Kidney international, 44(6), 1993, pp. 1322-1326
To delineate the incidence and risk factors for seroconversion (SC) fo
r HCV, from May 1991 to November 1992 we followed all 401 patients (no
i.v. drug abusers) dialyzed in 15 Belgian hemodialysis (HD) units, no
ne of which isolates anti-HCV (+) patients. The sensitive ELISA II tes
t was performed in the same laboratory for all patients. ELISA II (+)
sera were considered truly positive if specific antibodies were detect
ed by RIBA II against at least one HCV antigen. Blood transfusions giv
en from 12 months prior to inclusion in the study, dialyzer reuse and
frequency of dialysis monitor sterilization were recorded. In May 1991
, prevalence of truly positive ELISA II tests averaged 13.5% (54/399).
During the three consecutive six-month periods, ELISA II became truly
positive in 3 of 305 (1%), 4 of 314 (1.3%) and 1 of 313 (0.3%) patien
ts, respectively, which was an average yearly incidence of 1.7%. SC wa
s preceded (1 to 6 months) in all cases by an unexplained, unprecedent
ed increase in the alanine aminotransferase level. The mean monthly ra
te of transfusions was significantly higher (P < 0.001) in eight patie
nts with SC (0.7 +/- 0.6 U) than in 393 patients without SC (0.1 +/- 0
.01 U). However, three of eight patients with SC had not been transfus
ed at all. SC was observed in only 3 of 13 units (1, 3 and 4 cases, re
spectively) dialyzing ELISA (+) patients. In the unit with three SC, p
atients were always assigned a fixed station: SC was observed only in
patients dialyzed next to an ELISA II (+) patient (3 of 8 vs. 0 of 30,
P < 0.02). These facts suggest nosocomial transmission. SC was not as
sociated with dialyzer reuse or the lack of sterilization of the dialy
sis monitor after each session. In conclusion, the yearly incidence of
SC (ELISA II) averaged 1.7% in our group of hemodialyzed patients. Co
ntamination appeared to be both transfusional and nosocomial. The abse
nce of SC in 10 of 13 units dialyzing ELISA (+) patients suggests that
isolation of such patients is not yet warranted. Strict adhesion to t
he ''universal precautions'' (CDC, Atlanta) is probably sufficient to
prevent nosocomial transmission. Further long-term studies are needed
to confirm these conclusions.