Occult hepatitis B virus infection in dialysis patients: a multicentre survey.
BACKGROUND
The epidemiology and clinical significance of occult hepatitis B virus infection (serum hepatitis B surface antigen-negative patients with detectable hepatitis B virus viraemia in serum) remains controversial with only limited information about its prevalence in patients on long-term dialysis.


OBJECTIVE
To address the epidemiology of occult HBV infection in a large cohort of dialysis patients.


METHODS
We screened a large cohort (n = 585) of Italian chronic dialysis patients; from this population, a group of hepatitis B virus surface antigen seronegative patients (n = 213) was tested by Amplicor hepatitis B virus Monitor Test to detect hepatitis B virus viraemia (hepatitis B virus-DNA) in serum.


RESULTS
Occult hepatitis B virus infection was absent (zero of 213 = 0%). Persistent hepatitis B virus surface antigen carriage was less frequent than anti-hepatitis B virus core antibody (anti-hepatitis B core antigen) seropositive status in this study group [1.88% (11 of 585) vs. 36% (216 of 585), P = 0.0001]. No dialysis patients seropositive for anti-hepatitis B core antibody in serum (zero of 123 = 0%) had detectable hepatitis B virus-DNA by polymerase chain reaction technology. No significant association between abnormal biochemical liver tests and serum anti-hepatitis B core antibody was noted in our population. Nominal logistic regression analysis demonstrated an independent and significant relationship between anti-HCV antibody and anti-hepatitis B virus core antibody in serum (Wald chi-square 16.06, P = 0.0001). The rate of seropositive patients for anti-hepatitis B virus core antibody was higher among study patients than controls with normal renal function [36.9% (216 of 585) vs. 21.4% (59 of 275), P = 0.0001]; this difference partially persisted after correction for demographic parameters, and viral markers.


CONCLUSIONS
In conclusion, occult hepatitis B virus was absent in our study group. Anti-hepatitis B core antibody was significantly related to presence of anti-HCV antibody supporting shared modes of transmission. Clinical studies based on molecular biology techniques provided with higher sensitivity are planned.
Fabrizi
F
F
Division of Nephrology and Dialysis, Maggiore Hospital, IRCCS, Milano, Italy. fabrizi@policlinico.mi.it
Messa
P G
PG
Lunghi
G
G
Aucella
F
F
Bisegna
S
S
Mangano
S
S
Villa
M
M
Barbisoni
F
F
Rusconi
E
E
Martin
P
P
D016022:Case-Control Studies; D015331:Cohort Studies; D005260:Female; D006510:Hepatitis B Antibodies / Q000097:blood; D006512:Hepatitis B Core Antigens / Q000097:blood; D019694:Hepatitis B, Chronic / Q000097:blood / Q000453:epidemiology*; D006801:Humans; D007558:Italy / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D012044:Regression Analysis; D006435:Renal Dialysis / Q000706:statistics & numerical data*
D006510:Hepatitis B Antibodies; D006512:Hepatitis B Core Antigens