Effect of a soluble bacterial carbohydrate fraction on the viscosity of intestinal contents in healthy subjects and patients with Crohn's disease.

Supernatants of faecal suspensions from patients with Crohn's disease (CD) showed much lower viscosity than those from healthy subjects. Material responsible for the viscosity could be precipitated with ethanol. Gel filtration indicated that the viscosity was not due to the glycoprotein fraction but to a fraction with higher molecular weight and relatively high contents of muramic acid suggesting a bacterial origin.

The obligate anaerobic faecal flora of patients with Crohn's disease and their first-degree relatives.

The obligate anaerobic faecal floras of patients with Crohn's disease, their first-degree relatives, and healthy control subjects were compared. The flora of Crohn's patients contained more anaerobic gram-positive coccoid rods and gram-negative rods than that of healthy subjects; on this basis patients and healthy subjects formed two clusters with minor overlap. Nine of 26 children of Crohn's patients were also included within the Crohn's disease cluster.

[Serodiagnosis of Crohn's disease].

Three serological tests, recommended as being of diagnostic value for Crohn's disease, were evaluated in 39 patients with Crohn's disease and--as controls--in 27 patients with ulcerative colitis, 45 healthy persons and 65 patients with inflammatory diseases other than Crohn's disease or ulcerative colitis. The tests were the determination of (1) serum antibodies to pseudomonas-like organisms (PLO) by means of indirect immunofluorescence; (2) agglutinating serum antibodies to 4 strains of anaerobic gram-positive coccoid rods (species of Eubacterium, Peptostreptococcus and Coprococcus); and (3) serum antibodies to perinuclear antigens in buccal mucosa of Crohn's disease patients by immunofluorescence. The results indicate that the occurrence of high-titer antibodies to PLO is reasonably sensitive for Crohn's disease, but has a low specificity, and that antibodies to perinuclear antigens in buccal mucosa have both low sensitivity and specificity.

Selected bacterial antibodies in Crohn's disease and ulcerative colitis.

Agglutinins to four strains of anaerobic gram-positive coccoid rods (species of Eubacterium, Peptostreptococcus and Coprococcus) were found in significantly higher frequency in Crohn's disease (CD) than in ulcerative colitis (UC) and in other diseased control subjects and were virtually absent in apparently healthy subjects. When the posterior probability of having CD was calculated on the basis of these agglutination reactions, 64% of patients with CD and 34% of patients with UC but only 10% of diseased controls and none of the healthy controls were regarded as 'probable' or 'definite' cases of CD. However, the posterior probability of CD did not sharply differentiate between CD and UC but indicated chronic inflammatory bowel disease.