[Significance of hepatitis B core antibody as the only marker of hepatitis B infection].
BACKGROUND
Little is known about the clinical significance of the "anti-HBc alone" serological profile (absence of HBsAg and anti-HBs) in HBV infections. The objective of the present study was to estimate the prevalence of the anti-HBc alone immunological profile and the clinical-epidemiological characteristics of patients with this profile.


METHODS
Prospective, cross-sectional, descriptive study performed in 2002 and including patients with anti-HBc alone (HBsAg-negative, anti-HBs-negative and anti-HBc-positive). All the cases identified underwent the following microbiological tests: IgM anti-HBc, HBeAg, anti-HBe, anti-HDV, anti-HCV, anti-HIV, as well as HBV-DNA testing by qualitative nested-PCR. Furthermore, studies of serum biochemical parameters, blood counts and coagulation, as well as a clinical-epidemiological interview were performed in all patients.


RESULTS
Among 3900 patients studied, 195 (5%) presented the anti-HBc alone profile (48% were > 65 years old). Residual anti-HBs (< 10 mUI/mL) was found in 44% of cases and 33% were anti-HBe positive. HCV or HIV coinfection were seen in 38% and 8%, respectively. HBV-DNA was detected in 4.2% (5/120) of cases. Epidemiologically, detection of anti-HBc alone was casual in 60% of patients, whereas the remaining cases had a history of chronic liver disease (82% of these were anti-HCV positive). In a high percentage (63%) the transmission mechanism of HBV infection was unknown (11% intravenous drug abuser, 10% surgery, 6% transfusions).


CONCLUSIONS
The anti-HBc alone pattern is a frequent finding, particularly in patients > 65 years old and in HCV or HIV coinfected patients. Although HBV-DNA was detected in a small percentage of cases, this test could be indicated in certain clinical situations (liver disease, coinfection, donors). Furthermore, this profile seems to be related with HCV infection; hence, we consider anti-HCV detection necessary in all patients with anti-HBc alone.
Colomina-Rodríguez
Javier
J
Servicio de Microbiología y Unidad de Investigación en Patología Infecciosa, Hospital de La Ribera, Ctra. Alcira-Corbera, km. 1, 46600 Alcira, Valencia, Spain. jcolomina@hospital-ribera.com
González-García
David
D
Burgos-Teruel
Antonio
A
Fernández-Lorenz
Natalia
N
Guerrero-Espejo
Antonio
A
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000437:Alcoholism / Q000453:epidemiology; D015415:Biomarkers; D002648:Child; D002675:Child, Preschool; D015897:Comorbidity; D003430:Cross-Sectional Studies; D004279:DNA, Viral / Q000097:blood; D003920:Diabetes Mellitus / Q000453:epidemiology; D005260:Female; D015658:HIV Infections / Q000453:epidemiology; D006509:Hepatitis B / Q000097:blood / Q000175:diagnosis* / Q000453:epidemiology / Q000276:immunology / Q000635:transmission; D006510:Hepatitis B Antibodies / Q000097:blood*; D006511:Hepatitis B Antigens / Q000097:blood; D006512:Hepatitis B Core Antigens / Q000276:immunology*; D006515:Hepatitis B virus / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification; D006526:Hepatitis C / Q000453:epidemiology; D003699:Hepatitis D / Q000453:epidemiology; D006801:Humans; D007075:Immunoglobulin M / Q000097:blood / Q000276:immunology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012307:Risk Factors; D016036:Seroepidemiologic Studies; D013030:Spain / Q000453:epidemiology; D015819:Substance Abuse, Intravenous / Q000453:epidemiology
D015415:Biomarkers; D004279:DNA, Viral; D006510:Hepatitis B Antibodies; D006511:Hepatitis B Antigens; D006512:Hepatitis B Core Antigens; D007075:Immunoglobulin M