A high sensitivity assay is more accurate than a classical assay for the measurement of plasma CRP levels in endometriosis.

Leuven University Fertility Centre, Department of Obstetrics & Gynaecology, University Hospital Gasthuisberg, Leuven, Belgium.
Reproductive Biology and Endocrinology (Impact Factor: 2.14). 08/2011; 9:113. DOI: 10.1186/1477-7827-9-113
Source: PubMed

ABSTRACT Endometriosis is associated with chronic subclinical inflammation. C-reactive protein (CRP), a marker of inflammation, could serve as a biomarker of endometriosis. We tested the hypothesis that a high sensitivity CRP assay (hsCRP) is more accurate than a classical CRP assay in the detection of subclinical inflammation in plasma of women with endometriosis.
CRP levels were measured by hsCRP and classical CRP assays in plasma of 204 women with endometriosis and 91 women without endometriosis. Both assays were compared with respect to their value for the diagnosis of endometriosis.
The number of plasma samples with detectable CRP was significantly higher (100%) using the hsCRP assay when compared to the classical CRP assay (42.7%) (p < 0.0001). Significantly increased CRP plasma levels were found in women with endometriosis when compared with controls when the hsCRP assay was used in samples obtained during the luteal phase (p = 0.008). The highest discriminative ability for the diagnosis of endometriosis was also obtained using the hsCRP assay during the luteal phase, especially for moderate -severe endometriosis. At a cut-off level of hsCRP > 0.71 mg/L, moderate-severe stages were diagnosed with 80.7% sensitivity and 63.9% specificity during the luteal phase. Using a similar cut-off value for CRP analyzed by the classical method, moderate-severe endometriosis was diagnosed with lower sensitivity (67.7%, p = 0.06) and comparable specificity (63.9%).
The hsCRP assay was superior to the classical CRP assay for the detection of low CRP levels and for revealing subclinical inflammation in plasma of women with endometriosis.

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: At present, the only way to conclusively diagnose endometriosis is laparoscopic inspection, preferably with histological confirmation. This contributes to the delay in the diagnosis of endometriosis which is 6-11 years. So far non-invasive diagnostic approaches such as ultrasound (US), MRI or blood tests do not have sufficient diagnostic power. Our aim was to develop and validate a non-invasive diagnostic test with a high sensitivity (80% or more) for symptomatic endometriosis patients, without US evidence of endometriosis, since this is the group most in need of a non-invasive test. A total of 28 inflammatory and non-inflammatory plasma biomarkers were measured in 353 EDTA plasma samples collected at surgery from 121 controls without endometriosis at laparoscopy and from 232 women with endometriosis (minimal-mild n = 148; moderate-severe n = 84), including 175 women without preoperative US evidence of endometriosis. Surgery was done during menstrual (n = 83), follicular (n = 135) and luteal (n = 135) phases of the menstrual cycle. For analysis, the data were randomly divided into an independent training (n = 235) and a test (n = 118) data set. Statistical analysis was done using univariate and multivariate (logistic regression and least squares support vector machines (LS-SVM) approaches in training- and test data set separately to validate our findings. In the training set, two models of four biomarkers (Model 1: annexin V, VEGF, CA-125 and glycodelin; Model 2: annexin V, VEGF, CA-125 and sICAM-1) analysed in plasma, obtained during the menstrual phase, could predict US-negative endometriosis with a high sensitivity (81-90%) and an acceptable specificity (68-81%). The same two models predicted US-negative endometriosis in the independent validation test set with a high sensitivity (82%) and an acceptable specificity (63-75%). In plasma samples obtained during menstruation, multivariate analysis of four biomarkers (annexin V, VEGF, CA-125 and sICAM-1/or glycodelin) enabled the diagnosis of endometriosis undetectable by US with a sensitivity of 81-90% and a specificity of 63-81% in independent training- and test data set. The next step is to apply these models for preoperative prediction of endometriosis in an independent set of patients with infertility and/or pain without US evidence of endometriosis, scheduled for laparoscopy.
    Human Reproduction 06/2012; 27(9):2698-711. · 4.67 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Endometriosis affects 10% of premenopausal women and 35-50% of women with infertility, pelvic pain, or both. At present, endometriosis can only be diagnosed with surgery, where laparoscopy is considered a gold standard. Noninvasive biomarkers are thus urgently needed. In 2010, the peripheral biomarkers of endometriosis were systematically reviewed by May et al. However, with the introduction of '-omics' technologies, we have witnessed immense progress in biomarker discovery, which now calls for an overview of recent studies. This report looks at potential blood and urine biomarkers of endometriosis published in the last 3 years. The current status of noninvasive diagnostic biomarkers of endometriosis is discussed, with the limitations of these studies identified and recommendations for future biomarker discovery provided.
    Expert Review of Molecular Diagnostics 04/2014; 14(3):365-85. · 4.09 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The pathogenesis of endometriosis is associated with an inflammatory process. Here, we assessed if the levels of high-sensitivity C-reactive protein (hs-CRP) in serum could constitute an effective method for detecting systemic inflammation during endometriosis. This was a prospective, laboratory-based study, which was carried out in a tertiary-care university hospital. Patients with histologically proven endometriosis (n=370) and unaffected women (n=464) were enrolled between January 2005 and December 2009. We performed complete surgical excision of endometriotic lesions with pathological analysis. In addition, hs-CRP levels were determined through a particle-enhanced immunoturbidimetric method. Hs-CRP levels were measured in both controls and women with endometriosis according to the established surgical classifications of endometriosis: superficial (SUP), endometrioma (OMA), and deep infiltrating endometriosis (DIE). Also, hs-CRP levels were evaluated according to hormonal treatment and menstrual cycle. Hs-CRP serum levels did not statistically differ between women with endometriosis and controls (median in ng/mL [range]: 0.82 [0.04-42.89] vs. 0.9 [0.03-43.73], respectively; p=0.599). Moreover, subgroup analysis revealed no difference between SUP, OMA, DIE, and controls: 0.8 (0.15-13.35), 0.81 (0.04-38.82), 0.83 (0.09-42.89), and 0.9 (0.03-43.73), respectively (p=0.872). Furthermore, no effect was observed regarding hormonal treatment or menstrual cycle. Although endometriosis is an inflammatory disease, we failed to identify any systemic changes in hs-CRP serum levels. Therefore, hs-CRP analysis appears to be irrelevant to the diagnosis and staging of endometriosis.
    American journal of obstetrics and gynecology 01/2014; · 3.28 Impact Factor

Full-text (2 Sources)

Available from
Jun 2, 2014