Objectives:

Since being first described in the late 1970s relapsing pseudomebranous colitis occurs in 10–20% of patients after being treated with oral metronidazole, vancomycin or bacitracin. Previous studies in children with relapsing C. difficile colitis have shown low or absent levels of toxin A antibodies. We studied eight adult patients with relapsing C. difficile colitis who were hospitalised with profound diarrhoea and dehydration.

Methods:

Eight adult patients were studied ranging in age from 55 to 78 years. All had at least 1 positive stool for C. difficile Toxin A or B by ELISA assay. Toxin A specific-immunoglobulin was also assayed by ELISA using flat-bottom microtitre plates and were incubated overnight with toxin A in carbonate buffer. Horseradish peroxidase conjugated affinity-purifed goat anti-human IgG was added. The OD was measured at 405 nm on a microELISA plate reader. Patients received oral vancomycin at a dose of 500 mg thrice daily together with IVIG, 30 g twice within 48 h. Five patients also received Saccharomyces boulardii orally twice daily.

Results:

All eight patients failed to produce detectable C. difficile antibody. Treatment with oral vancomycin and IVIG resulted in disappearance of diarrhoea and normalisation of leucocytosis within 4 days of initiating treatment. C. difficile toxin was no longer demonstrable in the stool by day 5 of treatment, although rectal bleeding persisted in two patients with severe pseudomembranous colitis. None of these eight patients had recurrent disease after treatment.

Conclusion:

A combination of oral vancomycin together with IVIG appears to be successful treatment in patients with relapsing C. difficile colitis. All eight patients in this small study were defective in their ability to produce specific antibody to toxin A. Further studies evaluating the nature of the defect in specific antibody formation that likely is responsible for this syndrome are currently underway.