title: [Chronic hepatitis B virus (HBV) infection: usefulness of the combination of HBeAg and ALT determination to predict a high HBV-DNA level and therefore the necessity of referral to a specialist for possible antiviral treatment].
abstract: OBJECTIVE
  To assess the usefulness of a simple practical guideline based on hepatitis B e-antigen (HBeAg) status and a single alanine aminotransferase (ALT) determination to predict hepatitis B virus (HBV) load in chronic HBV patients as a criterion for referral to a specialist for possible antiviral therapy.
  
  
  METHODS
  Prospective observational study.
  
  
  METHODS
  420 patients with chronic HBV infection were seen at the Municipal Health Service (MHS) in Rotterdam between 2002 and 2005. The usefulness ofa guideline based on HBeAg positivity and/or elevated ALT levels to predict high HBV DNA levels (defined as more than 10(5) copies/ml) was determined. Patients with HBeAg or an elevated ALT level were referred to a specialist according to the practical guideline. Positive and negative predictive value, sensitivity, and specificity of the referral guideline for a high HBV-DNA level were calculated.
  
  
  RESULTS
  Less than half, 43% (181/420) of the patients, were eligible for referral to specialist care. The positive predictive value of the referral guideline was 45% (82/181, 95% CI: 38-53). The negative predictive value, i.e. the proportion of patients with low viral loads who were (rightly) not selected for referral, was 95% (227/239; 95% CI: 71-97). The sensitivity was 87% (95% CI: 80-93): the patients selected included 82 of 94 patients with a high HBV DNA level. Of the 12 patients with high viral loads not referred according to the guideline, 11 had a viral load of between 10(5)-10(6) copies/ml.
  
  
  CONCLUSIONS
  A referral guideline based on HBeAg status and a single ALT determination can successfully predict viral load in chronic HBV patients and can be used in primary care to select patients for referral to specialist care. This guideline may limit the number of unnecessarily referred patients, enhancing the efficiency of the care for patients with chronic HBV infection.
authors.affiliation: GGD Rotterdam-Rijnmond, Cluster Infectieziektebestrijding, Postbus 70.032, 3000 LP Rotterdam. veldhuijzeni@ggd.rotterdam.nl
authors.forename: I K
authors.initials: IK
authors.lastname: Veldhuijzen
authors.forename: M C
authors.initials: MC
authors.lastname: Mostert
authors.forename: H G M
authors.initials: HG
authors.lastname: Niesters
authors.forename: J H
authors.initials: JH
authors.lastname: Richardus
authors.forename: R A
authors.initials: RA
authors.lastname: de Man
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000410:Alanine Transaminase / Q000097:blood*; D000998:Antiviral Agents / Q000627:therapeutic use*; D015415:Biomarkers / Q000097:blood; D002648:Child; D004279:DNA, Viral / Q000032:analysis; D005260:Female; D006513:Hepatitis B e Antigens / Q000097:blood*; D019694:Hepatitis B, Chronic / Q000097:blood* / Q000188:drug therapy; D006801:Humans; D008297:Male; D008875:Middle Aged; D017410:Practice Guidelines as Topic; D011237:Predictive Value of Tests; D012017:Referral and Consultation; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D019562:Viral Load
chemical_list: D000998:Antiviral Agents; D015415:Biomarkers; D004279:DNA, Viral; D006513:Hepatitis B e Antigens; D000410:Alanine Transaminase