Comparison of 17-hydroxyprogesterone Levels in Infants with ELISA and LC-MS/MS Measurement Methods

Objective: Although enzyme-linked immunosorbent assay (ELISA) is frequently used in the routine measurement of the steroid hormone 17-hydroxyprogesterone (17-OHP) level, there are studies on other methods.In our study, we compared the discordance of 17-OHP level in ELISA with liquid chromatography-tandem mass spectrometry (LC-MS/MS).Methods: 17-OHP level was measured in the serums of infants up to 5 months of age at University of Health Sciences Trkiye, Baakehir am and Sakura Hospital between May 1, 2022 and September 10, 2022.One hundred and thirty four sera had 17-OHP level above the reference range measured by ELISA, and 17-OHP level was measured with LC-MS/MS.After examining 17-OHP level in these sera with 2 different measurement methods, the obtained data were statistically analyzed using the SPSS 20.0 software package.Results: 17-OHP level was detected above the reference range in 134 out of 134 sera (100%) by ELISA.17-OHP level in 106 (79.1%) of the sera was detected within the reference range by LC-MS/MS.In statistical analysis, comparison of 17-OHP level with 2 different measurement methods was performed by chi-square test.A significant difference (p<0.0001) was observed in the 2x2 table in the chi-square test. Conclusion:ELISA is widely used as a cost-effective method in measuring 17-OHP level, a steroid hormone.Differences that may occur due to the metabolism of 17-OHP in infants may lead to a false increase in ELISA.Due to this increase in routine, a more expensive and sensitive method, LC-MS/MS can also be used.In our study, we emphasized the importance of confirming falsely increased 17-OHP levels measured by ELISA with LC-MS/MS in infants younger than 3 months.