Automated quantification of choriogonadotropin: analytical correlation between serum and urine with creatinine...

We evaluated the Boehringer Mannheim Diagnostics ES 600 automated immunoassay system for measuring choriogonadotropin (hCG) in human serum, plasma, and urine. The ES 600, an automated sample-selective, multibatch analyzer, is based on immunoenzymometric coated-tube technology. Interassay CVs for assay of both serum and urine ranged from 2% to 16%. The analytical sensitivity was 0.5 int. unit/L. Results for serum correlated well with qualitative "Icon" and quantitative "Tandem" assays (Hybritech). In addition, results for serum and urinary hCG correlated well when the latter was expressed in terms of creatinine excretion. These results suggest that determination of hCG in urine can be correlated with those in serum for use as a marker for chorionic tumors or for screening abnormal pregnancies, where the rate of hCG production may be important.