Background. The hepatitis C virus infection is highly prevalent in. patient
s on chronic dialysis. There are more than 10 variants of the hepatitis C v
irus, with 55 to 72% of identity among them at the amino acid level. Howeve
r, we do not Know the specific genotype in dialysis patients in. Mexico. Th
us, the aim of the present study was to Know the specific genotypes of the
C virus in infected dialysis patients, to Know the distribution of genotype
s in the different dialysis techniques and to Know the relation between gen
otype and hepatic disease stage. Methods. We performed a prospective, trans
versal and comparative study in patients in dialysis in three hospital cent
ers in the south of Mexico City. The presence of C-type hepatitis infection
was assessed by ELISA II and qualitative RT-PCR in blood samples. The geno
type of the hepatitis C virus was determined by analysis of the restriction
pattern of the RT-PCR product using Mva I, Hinf I, BstU I and Serf I restr
iction enzymes. Variables analyzed were: age, gender, etiology of renal fai
lure, hind and time in substitutive therapy, transfusion and hepatitis hist
ory, liver function test, blood urea, serum creatinine and blood cell count
. Results. We studied 235 dialysis patients that were divided following the
ir dialysis modality into: 132 in continue ambulatory peritoneal dialysis (
CAPD), 17 in CAPD, but with history of hemodialysis (PD/HD) of at least one
month and 86 on hemodialysis (HD). The hepatitis infection was detected in
24 of the 235 patients (CAPD = 4.5%, PD/HD = 41.1% and HD = 12.7%; p < 0.0
01). The most com mon genotype was 1B (12/24), followed by 1A and 2A (4/24
each one), and finally by 2B and 2C (2/24 each one). We detected no patient
s with genotypes 3 to 6. The patients with 2A genotype were older than thos
e infected with 1A (p < 0.05). History of surgery, transfusions, and hepati
tis was similar in all genotypes. Finally the time in dialysis was longer i
n patients with 2A genotype than others (2A = 60.5 +/- 71.5 months, vs. 1A
= 11.5 +/- 11.3, 1B = 26 +/- 26.4 y 2B/C = 17.5 +/- 13.4), but the differen
ce did not reach statistical significance. The genotype distribution betwee
n dialysis techniques showed that 1B genotype was the most frequent in all
modalities. The IA genotype was present in similar proportions in patients
of the three dialysis groups, the 2C genotype was present only in patients
with CAPD. Finally, the 2B was only found in hemodialysis patients. Discuss
ion. The assessment of viral genotype revealed that IB is the most common g
enotype in patients on. chronic dialysis in Mexico City. The fact that the
1B and IA genotypes were the most common types in our dialysis population s
uggest that transmission was similar to the general population; that is, pr
obably by blood transfusions.