The Dienes effect as an epidemiological tool in a paraplegic unit.

The authors study the Dienes effect in 136 P.mirabilis and 2 P.vulgaris strains, isolated from different infection or colonization sites, in 27 spinal cord injured patients, admitted to a Paraplegic Unit, during a 9 month period. It is shown that 7 cross-infection and 18 cross-contamination episodes occurred, affecting 13 of 27 patients, which indicates the great spreading capacity of these microorganisms; 97% of the results obtained were observed once again after 6 months' storage of strains. In addition, in 7 of these strains their resistance to several antibiotics was cured by treating them with acriflavine salts, demonstrating that the Dienes effect persists even when resistance to antibiotics is modified; the authors conclude that the Dienes effect is an accurate stable epidemiological tool to identify cross-infections and its origins, and to facilitate the interruption of the chain of infection.