Serum lysozyme, serum proteins, and immunoglobulin determinations in nonspecific inflammatory bowel disease.

The serum levels of lysozyme, serum electrophoresis, and serum immunoglobulins were determined prospectively in 101 patients with ulcerative colitis, ulcerative proctitis, Crohn's disease, or nonclassifiable nonspecific inflammatory bowel disease. Although the mean serum lysozyme concentration of patients with Crohn's disease (10.5 +/- 6.8 microgram/ml) and ulcerative colitis (9.6 +/- 4.1 microgram/ml) performed by a standardized lysoplate method was significantly greater than normal controls (6.0 +/- 1.5 microgram/ml), the results did not correlate with the diagnosis nor with the degree of disease activity. Individually separated protein fractions and serum immunoglobulins also did not correlate with the serum lysozyme levels. This study indicates that measurement of the level of serum lysozyme in individual patients is not helpful in determining the cause or degree of activity of nonspecific inflammatory bowel disease.