Serum bactericidal resistance of faecal Escherichia coli and bactericidal competence of serum from patients with ulcerative colitis.
A microtitre method was developed to screen Escherichia coli from 48 patients with ulcerative colitis and 25 controls for serum resistance. Bactericidal resistance was indicated by a change in colour of indicator due to acid production by viable organisms and quantitated by a change in absorbance. The method clearly differentiated between organisms confirmed as resistant or sensitive by conventional techniques. Twenty four (50%) disease and 14 (56%) control E coli specimens showed serum resistance. Bactericidal competence of sera from patients with ulcerative colitis was assessed by incubating sensitive E coli with sera from 10 patients with ulcerative colitis and pooled normal serum. All sera effectively reduced viable counts to less than 6% of original inoculum. This study shows that serum samples from patients with ulcerative colitis are bactericidally competent and that there is no increase in the number of serum resistant E coli in patients with ulcerative colitis.
Gastroenterology Unit, General Infirmary, Leeds.
D A
DA
Burke
S A
SA
Clayden
A T
AT
Axon
D001431:Bacteriological Techniques; D001770:Blood Bactericidal Activity / Q000276:immunology*; D003093:Colitis, Ulcerative / Q000276:immunology*; D015169:Colony Count, Microbial; D004926:Escherichia coli / Q000276:immunology*; D005243:Feces / Q000382:microbiology; D005260:Female; D006801:Humans; D008297:Male