Crohn's disease: small bowel motility impairment correlates with inflammatory-related markers C-reactive protein and calprotectin.

BACKGROUND: To evaluate the correlation between the levels of C-reactive protein (CRP), calprotectin, and small bowel motility in patients with Crohn's disease assessed with MRI. METHODS: This prospective institutional review board approved study included magnetic resonance imaging enterography (MRE) and analyses of inflammatory markers in blood (C-reactive protein) and feces (calprotectin). For cine MRE, a coronal 2D-T2w sequence was used on a 1.5 T MRI system. Small bowel motility was analyzed in 13 patients using dedicated magnetic resonance MR-motility assessment software (Motasso). Contraction frequency, amplitude, amplitude diameter ratio, and luminal diameter were determined as well as the blood levels of CRP (mg L(-1) ) and fecal levels of calprotectin (ug g(-1) ). Statistics were calculated using Pearson's correlation coefficient. KEY RESULTS: A significant inverse linear correlation was found between the contraction frequency and both the level of CRP (r = -0.701, P = 0.008) and calprotectin (r = -0.805, P = 0.001). Dilatation of small bowel diameter significantly correlated with calprotectin levels (r = 0.857, P =< 0.001) but not with CRP (r = 0.447, P = 0.126). The absolute amplitude of the contractions did not correlate neither with the level of CRP (r = -0.527, P = 0.064) nor with calprotectin (r = -0.612, P = 0.026). The ratio describing the contraction amplitude relatively to the individual luminal diameter significantly correlated with calprotectin (r = 0.736, P = 0.004) and with CRP (r = 0.577, P = 0.039). CONCLUSIONS & INFERENCES: Alterations of small bowel motility during CD flares significantly correlate with the level of calprotectin and CRP indicating that they represent inflammatory activity.

Studies on the absorption of sodium and chloride from the rumen of sheep.

The net absorption of Na and Cl from the temporarily isolated rumen of sheep was studied using an artificial ruminal fluid with different Na and K and constant Cl concentrations. The net absorption of Na and Cl was linearly correlated. The net absorption of Cl was abolished and a small net secretion was observed when no sodium was in the artificial rumen fluid. The net absorption of Na was significantly reduced under chloride free conditions. It is concluded that the active transport of Na and Cl is coupled. The mechanism of an Na-Cl cotransport can not be deduced from these studies.

Effect of intraruminal sodium and potassium concentrations and of the transmural potential difference on magnesium absorption from the temporarily isolated rumen of sheep.

The net absorption of magnesium from the temporarily isolated and washed reticulo-rumen of sheep has been studied using buffer solutions with different sodium, potassium and chloride concentrations. An increased potassium concentration led to an increased potential difference (p.d.) and a decreased magnesium absorption. The exchange of chloride in the buffer solutions with sulphate (at constant sodium and potassium concentrations) caused a significant increase of the p.d. and again a reduced net magnesium absorption indicating that the p.d. is an important factor associated with decreased net magnesium absorption. The replacement of sodium with lithium (at constant potassium concentrations) did not influence the net magnesium absorption. It is concluded that the low apparent availability of magnesium after an oral load of potassium is mainly caused by the high transmural potential difference across the rumen wall under such feeding conditions. However, the presented data cannot rule out an effect of potassium per se independent of the effect of the p.d.