Cytokeratin-19 as a biomarker in urine and in serum for the diagnosis of endometriosis – a prospective study

Abstract

Endometriosis compromises the quality of life of countless women worldwide and is a leading cause of disability. Clinical symptoms of endometriosis can be very heterogeneous leading to a long interval between onset of symptoms and surgical diagnosis. A noninvasive, rapid diagnostic test is urgently needed. In this prospective study, we evaluated the usefulness of Cytokeratin-19 (CK19) as a biomarker for the diagnosis of endometriosis through urine and serum ELISA. 76 reproductive-aged women undergoing laparoscopy for benign conditions were included to this study and divided into two groups by the presence (n = 44) or absence (n = 32) of endometriosis. There was no statistically significant correlation between the concentration of CK19 in urine (p = 0.51) or in serum (p = 0.77) and the diagnosis of endometriosis. Assigning the samples to the proliferative or secretory cycle stage did not sufficiently lower the p values. In this study, the promising data reported in the recent literature about CK19 serving as a sufficient biomarker for endometriosis could not be verified when tested in a larger sample size. Further studies are warranted to explore the usefulness of CK19 in the diagnosis of endometriosis.

Urine and serum concentrations of Cytokeratin 19 in preeclampsia

“…Thus, CK19 seems not to be a valuable urinary biomarker of PE, which might be attributed to the lack of understanding of the pathophysiology of excretion of cytokeratins in urine. This is also outlined by the fact that promising data indicating CK 19 as a valuable urinary biomarker for endometriosis could recently not be verified in a larger patient population by our group [22]. It could well be that CK 19 fragment is not primarily eliminated by renal clearance and thus is not suitable as a urinary biomarker at all.…”

Biomarkers for the Noninvasive Diagnosis of Endometriosis: State of the Art and Future Perspectives

“…Cytokeratin-19 (CK19) is another molecule that could be used in the detection of endometriosis. Kuessel et al [141] measured urinary levels of CK19 by ELISA on a cohort of 76 women. The study concluded that there was no significant correlation between urinary levels of CK19 and endometriosis.…”

Update on Biomarkers for the Detection of Endometriosis

“…Using an immunoblot technique, Tokushige et al demonstrated cytokeratin-19 (CK19) to be uniquely expressed in 11 urine samples from women with histologically proven endometriosis relative to samples from 6 women free of disease [ 102 ]. A larger prospective study was subsequently unable to confirm the diagnostic potential for urinary CK19 [ 103 ], possibly due to different specimen collection techniques or different subject characteristics. As in serum, matrix metalloproteinases (MMPs) have been investigated for association with endometriosis.…”