the sensitivity , specificity , and positive and negative predictive values of a single serum antibody titre of 1/128 or more as an indicator of recent infection compared with isolation of the organism in cycloheximide treated mccoy cells or antigen detection by chlamydiazyme ( abbot laboratories ; north chicago , illinois , usa ) , or both , were each 67 % .
C0020898
illinois
C0041703
usa