Serum creatine kinase in ectopic pregnancy and its association with tubal rupture: a hospital-based case control study

Abstract

Background: Ectopic pregnancy (EP) remains an important cause of morbidity in pregnancy and diagnosis may be difficult when clinical findings and ultrasonography are inconclusive. This study evaluated serum creatine kinase (CK) in EP and its relationship with tubal rupture.

Methods: This hospital-based case-control study included 50 women with EP and 50 women with confirmed intrauterine pregnancy (IUP), all at ≤14 weeks of gestation, at Pannadhaya Rajkiya Mahila Chikitsalaya, RNT Medical College, Udaipur. Clinical, risk-factor and ultrasonographic data were recorded and serum CK and β-hCG were measured. Continuous variables were compared using the independent-samples t-test and categorical variables using chi-square/Fisher's exact test, as appropriate.

Results: Mean serum CK was significantly higher in EP than in IUP (112.4±24.6 vs 54.8±16.2 IU/l; p<0.001). CK >100 IU/L occurred in 76% of cases versus 12% of controls. Among EP cases, 32 (64%) were ruptured and 18 (36%) were unruptured. Mean CK was higher in ruptured than unruptured EP (130±18 vs 95±15 IU/l; p<0.001). Mean β-hCG was lower in ruptured than unruptured EP (2800±700 vs 3500±900 mIU/ml; p<0.01). Pelvic inflammatory disease was associated with EP (OR 3.63; p=0.03).

Conclusions: Serum CK was significantly elevated in EP and was higher in ruptured disease. CK may provide adjunctive information regarding ectopic pregnancy and tubal injury, but should be interpreted with clinical assessment, ultrasonography and β-hCG rather than used as a standalone diagnostic test.