Interpreting a single antistreptolysin O test: a comparison of the "upper limit of normal" and likelihood ratio methods.


Journal Article

Single serologic tests may occasionally influence clinicians in making diagnoses. The antistreptolysin O (ASO) test is a frequently used tool for detecting recent Streptococcus pyogenes infection and is helpful in the diagnosis of diseases like rheumatic fever. Using data from a 1989 prospective study of 600 healthy male military recruits, in which 43% experienced S. pyogenes upper respiratory tract infection (2-dilution rise in ASO), this report compared two methods of interpreting a single ASO titer. Using the "upper limit of normal" (80 percentile) method, recruits with an ASO titer of greater than 400 showed evidence of recent S. pyogenes infection. This method had a sensitivity and specificity of only 65.9 and 81.9% respectively. In contrast to the "yes-no" dichotomy of the "upper limit of normal" method, the likelihood ratio method statistics were ASO value specific, more consistent with clinical judgment, and better emphasized the caution clinicians must use in interpreting a single ASO test.

Full Text

Duke Authors

Cited Authors

  • Gray, GC; Struewing, JP; Hyams, KC; Escamilla, J; Tupponce, AK; Kaplan, EL

Published Date

  • October 1993

Published In

Volume / Issue

  • 46 / 10

Start / End Page

  • 1181 - 1185

PubMed ID

  • 8410102

Pubmed Central ID

  • 8410102

International Standard Serial Number (ISSN)

  • 0895-4356

Digital Object Identifier (DOI)

  • 10.1016/0895-4356(93)90117-j


  • eng

Conference Location

  • United States