THE DISCRIMINATIVE ROLE OF CALPONIN-2 FOR ECTOPIC PREGNANCY

Abstract

Objectives

Since ectopic pregnancy is still the leading cause of mortality and morbidity, finding diagnostic markers have crucial role in this area (1,2). Calponin-2 (CNN2), found in tubal smooth muscle cells, increases with muscle tension (3). The aim of this study is to determine the role of CNN-2 in tubal ectopic pregnancies that leads to muscle tension in tuba.

Materials and Methods

A total of 195 patients between September 2022 and 2023 were included. Participants were divided into 3 groups as ectopic pregnancy (n=65), healthy first trimester pregnancy (n=80) and miscarriage (n=50). Demographic and laboratory findings were compared between groups.

Results

CNN2 levels were measured as 13.6(0.12-39.6) ng/ml in ectopic pregnancy, 0.18(0.12-5.34) ng/ml in miscarriage and 0.16 (0.12-1.4) ng/ml in healthy pregnancy which was statistically significant difference (p<0.001). In all patients, it was found that CNN2 above 0.49 ng/ml predicted ectopic pregnancy with 63.08% sensitivity and 98.52% specificity (AUC=0.793, p<0.001). Also, it was found that CNN2 above 0.41 ng/ml distinguished ectopic pregnancy from healthy pregnancy with 63.08% sensitivity and 98.82% specificity (AUC=0.807, p<0.001). In the logistic regression analysis, the rate of ectopic pregnancy was 8 times higher in cases with progesterone levels of 9.2 ng/ml and below compared to those without, and approximately 90 times higher in cases with CNN2 levels of 0.49 ng/ml and above compared to those without.

Conclusion

Serum CNN2 could be a valuable biomarker in distinguishing ectopic pregnancy from other pregnancies. We suggest that single measurement of CNN2 can be an alternative approach instead of serial beta hcg measurement.