COMPARISON OF 2 MARCESCINOTYPING METHODS PERFORMED ON 290 EPIDEMIC SERRATIA-MARCESCENS STRAINS

Two marcescinotyping methods, the mitomycin-C induction and the cross streaking, are compared using S. marcescens strains isolated in differ ent epidemiological situations. We found the induction method more rep roducible, showing less variations and giving more limited number of m arcescinotype patterns than the cross streaking method for the study o f nosocomial infections. Strains in each epidemiological situation sho wed the same dominant pattern by the induction method but the cross st reaking method often showed patterns very different thus making uneasy the classification. We have chosen the induction method for further i nvestigation of hospital infections.