Lysozyme in Chronic Ulcerative Colitis. ∗

It has been previously shown in experimental animals that there is a low lysozyme content of the colonic mucosa in contrast to that of the stomach and in assays of apparently normal segments of 3 human large intestines, surgically removed for carcinoma, the lysozyme concentration was similarly low (mean = 3.5 units/g tissue). However, following the observation that lysozyme was able to remove the surface mucus from the dog stomach, 1 the present investigation was undertaken to determine whether abnormal concentrations of this mucolytic enzyme were present in the feces of patients with chronic nonspecific ulcerative colitis.

Table I summarizes the results of the stool lysozyme determinations. It is to be noted that the concentration of the enzyme in the feces of the control individuals was low whether the determinations were made on specimens obtained following a normal bowel movement or after purging with magnesium sulfate or castor oil. Similarly, in 3 chronic ulcerative colitis patients whose disease necessitated ileostomy and colectomy, the lysozyme concentration of the ileal stools was uniformly low. Also, in the single patient with idiopathic diarrhea who failed to show any organic change in the mucosa of the gastro-intestinal tract, there was little lysozyme present in the stool. In marked contrast to the above noted findings was the elevated lysozyme concentrations in the fecal excretions of 12 patients in whom the diagnosis of nonspecific chronic ulcerative colitis was established by roentgen and proctoscopic examination and in whom exhaustive search for pathogenic bacteria and/or parasites was negative. Even more striking was the high titer of lysozyme found in specimens of mucus obtained from the rectosigmoid region of patients with this disease.