title: Factors for predicting positive results for anti-HAV IgM retesting among initially seronegative patients.
abstract: OBJECTIVE
  The standard diagnostic tool for acute hepatitis A is detection of anti-hepatitis A virus (HAV) immunoglobulin M (IgM). However, a negative result for anti-HAV IgM can be obtained in the early phase of infection. Among clinically suspicious seronegative patients, diagnosis of hepatitis A is sometimes recorded on retesting.
  
  
  METHODS
  This study included patients who had attended the Kyung Hee University East-West Neo Medical Center from November 2006 to October 2008. We evaluated 27 patients (15 men, 12 women) who had undergone repeated anti-HAV IgM testing.
  
  
  RESULTS
  Thirteen patients were diagnosed with hepatitis A after retesting, and 14 with non-hepatitis A (non-HA). High initial cutoff index (COI) for anti-HAV IgM (≥0.5), low serum total bilirubin (<1.4 mg/dl), and low platelet count (<165 × 10(3)/μl) were related to a positive result for anti-HAV IgM retesting, although this association was not statistically significant on multivariate analysis. In the HA group, 7 of 13 patients had an initial COI for anti-HAV IgM of >0.5 compared with none of 14 patients in the non-HA group.
  
  
  CONCLUSIONS
  Initial COI for anti-HAV IgM, serum total bilirubin, and platelet count were helpful for predicting positive results for retesting among initially seronegative patients.
authors.affiliation: Department of Internal Medicine, East-West Neo Medical Center, Kyung Hee University College of Medicine, Gangdong-gu, Seoul 134-090, Korea.
authors.forename: Hyun Phil
authors.initials: HP
authors.lastname: Shin
authors.forename: Joung Il
authors.initials: JI
authors.lastname: Lee
authors.forename: Sung Won
authors.initials: SW
authors.lastname: Jung
authors.forename: Jae Myung
authors.initials: JM
authors.lastname: Cha
authors.forename: Kwang Ro
authors.initials: KR
authors.lastname: Joo
authors.forename: So Young
authors.initials: SY
authors.lastname: Kang
mesh_terms: D000328:Adult; D000410:Alanine Transaminase / Q000097:blood; D001219:Aspartate Aminotransferases / Q000097:blood; D001663:Bilirubin / Q000097:blood; D005260:Female; D006506:Hepatitis A / Q000175:diagnosis* / Q000821:virology; D035922:Hepatitis A Antibodies / Q000097:blood; D006801:Humans; D007075:Immunoglobulin M / Q000097:blood; D008297:Male; D015999:Multivariate Analysis; D010976:Platelet Count; D012367:RNA, Viral / Q000097:blood
chemical_list: D035922:Hepatitis A Antibodies; D007075:Immunoglobulin M; D012367:RNA, Viral; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase; D001663:Bilirubin