The New Indian Journal of OBGYN. Epub Ahead of Print

Interleukin 15 as serum biomarker for ectopic pregnancy and missed abortion

Cimona Lyn Saldanha, Shaheera Ajaz, Insha Khan, Khushbu Bashir, Qurteeba Qadri, Roohi Rasool, Tabassum Parvez

ABSTRACT

Background: When patients with biochemically diagnosed pregnancy, presents with pain and or vaginal bleeding, the differential diagnosis between intrauterine pregnancy, missed abortion and ectopic pregnancy is challenging. There is present lack of clinically useful tests for the accurate diagnosis of ectopic pregnancy, unless an early intrauterine pregnancy (IUP) is visible by ultrasound. Objectives: To assess whether serum measurement of IL-15 at 6–8 weeks could contribute to the differential diagnosis between failed pregnancies (i.e ectopic pregnancy or missed abortions) and healthy intrauterine pregnancies. Materials and methods: We performed a prospective observational case control study of 75 patients . Among these 75 patients, 50 patients presented with early pregnancy with abdominal pain or vaginal bleeding between 6- 8 weeks of gestation and were either diagnosed as ectopic pregnancy (EP) (25) and missed abortion (MA) (25). 25 women with healthy intrauterine pregnancy (IUP) between 6-8 weeks of gestation served as the control group. Serum samples were collected at the initial visit before treatment. All diagnosis were histologically confirmed. Serum beta HCG and IL-15 were measured in all 75 patients. Results: The mean serum IL-15 levels were significantly higher in failed (ectopic & missed) as compared to normal pregnancies (58.51± 8.95 vs 47.90 ±9.66 pg/ml respectively)(p=0.001). However there was no significant difference in IL-15 levels between missed (58.47 ±10.94 pg/ml) and ectopic (58.91± 7.94 pg/ml) pregnancies (p=0.87). The AUC for failed vs normal pregnancy was 0.810 (p=0.000). At the IL15 reading of 49.47pg/ml, the sensitivity was 86% and the test expects 34.6% false positivity rate in distinguishing failed pregnancy (EP, MP) from normal pregnancy. However the AUC was 0.53 when we compared ectopic pregnancy with missed abortion. Conclusion: High IL15 levels were associated with failed pregnancies, so these patients need to be closely followed. Larger randomized controlled trials are needed to further explore the role of IL15 to distinguish ectopic pregnancy and missed abortion.