Abstract book 2011 - ISHAM

EXOPHIALA DERMATITIDIS AGENT OF COLONIZATION IN CYSTIC FIBROSIS INBELGIUM: PREVALENCE, SEROLOGY AND ANTIFUNGAL SUSCEPTIBILITYFrançoise Symoens 1 , Ann Packeu 1 , Anca Boeras 2 , Daniel Huang 2 , HectorRodriguez-Villalobos 2 , Anissa Léonard 3 and Patrick Lebecque 31 Scientific Institute of Public Health, Mycology-Aerobiology Service, Brussels, Belgium2 Department of Pediatrics, Cliniques Universitaires St Luc, Brussels, Belgium3 Department of Microbiology, Cliniques Universitaires St Luc, Brussels, BelgiumExophiala dermatitidis is a black yeast absent in the outdoor environment (soil, organicmatter) in temperate regions. Agent of cerebral mycoses in South East Asia inimmunosuppressed patients, this fungus in temperate region is mainly isolated from cysticfibrosis (CF) patients.At the first meeting of this Working Group, a prospective study of the prevalence of E.dermatitidis in CF Belgian patients was presented, and risk factors were evaluated. In thisstudy Ed was isolated from 5.8% (9 out of 154 patients); Aspergillus fumigatus (Af)colonization and genotype (F508del mutation) seems to be predisposing factors for E.dermatitidis colonization (Lebecque et al., 2010).The aim of this study was to evaluate the presence of precipitins for E. dermatitidis in thepatients with positive culture and to study the antifungal susceptibility of the E. dermatitidisisolates.Presence of precipitins. The serological study for presence of precipitins was realized blindlywith 20 sera (11 from patients with a positive culture for E. dermatitidis and 9 from patientswith a negative culture for E. dermatitidis) using in house protein extracts of E. dermatitidisand A. fumigatus. The table hereunder summarizes the results obtained.Concordance of the presence of precipitins for E. dermatitidis and positivity of the culture: 20 patients (11 withpositive and 9 with negative culture for E. dermatitidis)Concordance/ % Culture /Serology Remark(nb patient)Full (n = 13) 65% + culture / > 2 prec. lines, (n = 7)- culture / no prec. line (n = 6)Intermediate (n = 2) 10% + culture / 1 prec. line 1 patient with + culture Ed since 1 month1 patient with + culture Ed since 3 yearsNot concordant(n = 2)Not concordant(n = 2)10% - culture /1 prec. line10% + culture / no prec. line + culture for Ed since 3 years for bothpatients,+ culture for Af, no prec. line for Af for bothpatients5% - culture /2 prec. linesNot concordant(n = 1)Ed: Exophiala dermatitidis, Af: Aspergillus fumigatus+: positive culture, -: negative culture, prec. lines: precipitating linesA concordance of 75% between the presence of precipitins and positivity of the culture for E.dermatitidis was observed. Two patients with a positive culture for E. dermatitidis had noprecipitins for E. dermatitidis, although they are colonized since more than 3 year. One out ofthese two patients, after colonization by E. dermatitidis, became also colonized by the related