The cause of Crohn's disease is unknown, although alterations in intestinal permeability may play a primary role. Because we were interested in permeability changes that occur before the onset of intestinal inflammation, we took advantage of the known genetic predisposition to this disease and studied not only patients with Crohn's disease, but their clinically unaffected relatives as well. Intestinal permeability was assessed using the marker polyethylene glycol-400 ingested with a standard meal. We found that 17 normal volunteers absorbed 215 +/- 29.6 mg (mean +/- SE), whereas 11 patients with Crohn's disease absorbed 514 +/- 94.7 mg and their 32 healthy relatives absorbed 566 +/- 62.4 mg. The twofold increase in permeability of patients and their relatives (p less than 0.005 compared with controls) indicates that the intestinal defect in the ability to exclude larger sized molecules is not secondary to clinically recognized intestinal inflammation, but is a primary defect that may be an etiologic factor in this disease.

There are significantly elevated risks of febrile seizures on the day of receipt of DTP vaccine and 8 to 14 days after the receipt of MMR vaccine, but these risks do not appear to be associated with any long-term, adverse consequences.

Nondiabetic relatives of probands with IDDM who are in the first two decades of life, are members of multiplex pedigrees, and have increased titers of islet-cell antibodies are the most likely to contract IDDM themselves.

No abstract

Preliminary design, data collection, and analytic capability of the Vaccine Safety Datalink project has been validated by replication of previous known associations between seizures and DTP and MMR vaccines. The diversity in vaccine administration schedules permits potential disentangling of effects of simultaneous and combined vaccinations. The project provides a model of public health-managed care collaborations in addition to an excellent infrastructure for safety and other studies of vaccines.