Fecal calprotectin (FC) is a highly sensitive disease activity biomarker in inflammatory bowel disease. However, there are conflicting reports on whether the diagnostic accuracy in Crohn's disease is influenced by disease location. The aim of this study was to undertake a systematic review of the published literature. Relevant databases were searched from inception to November 8, 2016 for cohort and case control studies which had data on FC in patients with isolated small bowel (SB) and large bowel (LB) Crohn's disease. Reference standards for disease activity were endoscopy, magnetic resonance imaging, computed tomography or a combination of these. The QUADAS-2 research tool was used to assess the risk of bias. There were 5,619 records identified at initial search. The 2,098 duplicates were removed and 3,521 records screened. Sixty-one full text articles were assessed for eligibility and 16 studies were included in the final review with sensitivities and specificities per disease location available from 8 studies. Sensitivities of FC at SB and LB locations ranged from 42.9% to 100% and 66.7% to 100% respectively while corresponding specificities were 50% to 100% and 28.6% to 100% respectively. The sensitivities and specificities of FC to accurately measure disease activity in Crohn's disease at different disease locations are diverse and no firm conclusion can be made. Better studies need to be undertaken to categorically answer the effect of disease location on the diagnostic accuracy of FC.
Bias (Epidemiology) ; Case-Control Studies ; Cohort Studies ; Crohn Disease ; Endoscopy ; Humans ; Inflammatory Bowel Diseases ; Leukocyte L1 Antigen Complex ; Magnetic Resonance Imaging

Purpose: Determination of oxygen concentration in tissues affected by chronic venous insufficiency (CVI) has shown inconsistent results over the years and has confounded the pathophysiology of venous diseases. This study measured transcutaneous partial oxygen pressure (TcPO2 ) levels in patients with CVI to assess oxygenation and variation in oxygenation according to CVI stage. Materials and Methods: A prospective study was performed on consecutive patients with unilateral CVI. TcPO2 of diseased and unaffected limbs was measured in the supine and dependent positions. A single TcPO2 value was measured at the site of greatest skin change or at the edge of the ulcer. The TcPO2 values were analyzed and compared according to stage. Results: A total of 96 patients were included in the study with C4 (24.0%), C5 (19.8%), and C6 (56.3%) disease. The mean age was 44.7 years, and 85 (88.5%) were male. There was a statistically significant (P<0.01) difference in mean TcPO2 levels between the unaffected limb (supine, 32.1 mmHg; dependent, 50.7 mmHg), C5 diseased limb (supine, 16.6 mmHg; dependent, 35.5 mmHg), and C6 diseased limb (supine, 24.2 mmHg; dependent, 40.4 mmHg). In the supine and dependent positions, the mean TcPO2 in the affected limb was significantly lower (P<0.01) than that in the unaffected limb. Conclusion TcPO2 in advanced CVI can be used as a marker of oxygenation status. This is the first study in an Indian population looking at the relevance of TcPO2in the prognostication of advanced CVI.

Purpose: Determination of oxygen concentration in tissues affected by chronic venous insufficiency (CVI) has shown inconsistent results over the years and has confounded the pathophysiology of venous diseases. This study measured transcutaneous partial oxygen pressure (TcPO2 ) levels in patients with CVI to assess oxygenation and variation in oxygenation according to CVI stage. Materials and Methods: A prospective study was performed on consecutive patients with unilateral CVI. TcPO2 of diseased and unaffected limbs was measured in the supine and dependent positions. A single TcPO2 value was measured at the site of greatest skin change or at the edge of the ulcer. The TcPO2 values were analyzed and compared according to stage. Results: A total of 96 patients were included in the study with C4 (24.0%), C5 (19.8%), and C6 (56.3%) disease. The mean age was 44.7 years, and 85 (88.5%) were male. There was a statistically significant (P<0.01) difference in mean TcPO2 levels between the unaffected limb (supine, 32.1 mmHg; dependent, 50.7 mmHg), C5 diseased limb (supine, 16.6 mmHg; dependent, 35.5 mmHg), and C6 diseased limb (supine, 24.2 mmHg; dependent, 40.4 mmHg). In the supine and dependent positions, the mean TcPO2 in the affected limb was significantly lower (P<0.01) than that in the unaffected limb. Conclusion TcPO2 in advanced CVI can be used as a marker of oxygenation status. This is the first study in an Indian population looking at the relevance of TcPO2in the prognostication of advanced CVI.