M032: INCREASED ISOLATION OF UNCOMMON MULTIRESISTANT NON-FERMENTING
ORGANISMS IN CYSTIC FIBROSIS
M.L.Belli . G.Manno, E.Ugolotti, M.L.Fenu, B.Tubino* and C.Jannuzzi.(II
Dept. of Infectious Diseases ,* Dept. of Paediatrics University
of Genoa "G.Gaslini" Institute - Genoa, Italy.)
Some non fermenting organisms (NFO) other than P.aeruginosa and B.cepacia are rarely reported as pathogenic as they are not isolated very often from the sputum of Cystic Fibrosis patients (pts): usually they are present in a low number and their isolation is difficult .
The isolation of uncommon NFO from clinical specimens can depend upon the use of selective media .In our center ,in 1992 , we introduced in the routine laboratory practice ,in addition to McConkey agar, a medium ( Eosin Metilen Blue agar - Difco ) made selective by the supplementation with antibiotics (aminoglycosides, vancomycin and amphotericin B ) ,with the aim to increase the isolation of uncommon NFO . We reviewed microbiological data collected between 1992 and 1994 and we found an increased isolation of NFO as shown in the following table ( n = number of strains; % = percentage related to total isolated strains )
X.malthophilis A.sylososidans other*
n % n % n %
1992 15 1.8 27 3.2 14 1.3
1993 29 3.7 29 3.7 11 1.8
1994 49 3.8 62 4.8 20 2
Alcaligens spp, Alcaligenes denitrdicans, Commamonas acidovorans, Ocrobactum anthropi, Flavobacteriurn spp., CDC IV-C2, Acinetobacter calcoaceticus ,P.fluorescens /putida.
These NFO are in general multiresistant, particularly to aminoglycosides The following table shows the % of resistance:
n°strain tobra cipro azthr unipen ceftaz cefope cefbro pipera s XM 78 100 67,5 93,5 90.9 53 64 100 53,2 AX 91 100 77 95,6 7.7 44 37.4 95,6 19,8 other 74.2 32,2 74,2 6,4 38,7 45.1 87 35,5 31