Preventive effect of an E. coli-filtrate (Colibiogen) in polymorphous light eruption.

During the administration of Colibiogen, a commercially available E. coli-filtrate, there was a significant (P less than 0.01) increase of the test dose of UVA necessary to elicit skin lesions in nine patients with polymorphous light eruptions. Control tests performed in the same manner without the drug indicate that this was due to treatment. Colibiogen appears to be of value in the treatment of polymorphous light eruption (PLE).