Scedosporium apiospermum seroprevalence study in a large cohort of - - PowerPoint PPT Presentation

Scedosporium apiospermum seroprevalence study in a large cohort of patients with cystic fibrosis in France

Perrine Parize, Sandrine Billaud, Raymond Robert, Stéphane Picot, Florence Persat, Anne Lise Bienvenu, Olivier Lortholary, Gabriel Bellon and Isabelle Durieu.

Centres de Ressources et de Compétences de la Mucoviscidose, Lyon; Groupe d’Etude des Interactions Hôte-Pathogène, UPRES-EA 3142, Angers; Laboratoire paludisme, parasites du sang et mycologie médicale, Lyon; Centre National de Référence des Mycoses et des Antifongiques, CNRS URA3012, Institut Pasteur, Paris, France. CNRMA

Scedosporium apiospermum

 initially considered as the anamorph of

Pseudallescheria boydii

 ubiquitous saprophytic filamentous fungus  culture : floccose colonies initially white,

becoming dark gray

 microscopic features of the anamorph state

• hyaline and septate vegetative hyphae
• anellidic conidiogenesis producing oval,

brown, unicellular conidia

Clinical manifestations

 emerging fungal pathogen  large spectrum of clinical manifestations :

• mycetoma
• sinopulmonary infections (necrotizing

pneumonia, sinusitis)

• osteomyelitis, septic arthritis
• brain abscess
• ocular infections
• disseminated infections in

immunocompromised hosts

• S. apiospermum and Cystic Fibrosis

Clinical manifestations in cystic fibrosis patients :

 colonization Cimon et al, Eur J Clin Microbiol Infect Dis 2000  allergic bronchopulmonary mycosis  endobronchitis Vazquez-Tsuji et al, Rev Iberoam Micol 2006  spondylitis Guignard et al, J Cyst Fibros 2008  disseminated infection Symoens et al, J Heart Lung Transplant 2006 Sahi et al, J Heart Lung Transplant 2007 Cooley et al, Emerg Infect Dis 2007

Problematics

 emerging pathogen  severity of the infection with frequently a fatal outcome

in patients with lung transplantation

 few epidemiological data  many questions about colonization by S. apiospermum :

• prognostic factor for unfavorable outcome ?
• frequency of invasive infections ?
• management of colonized patients ?
• preemptive strategy ?

Study Objectives

Main Objective :

 estimate S. apiospermum seroprevalence in a group of

pediatric and adult patients with cystic fibrosis Secondary Objectives :

 study the age-prevalence profiles  compare clinical and paraclinical data of S. apiospermum

seronegative and seropositive patients

 evaluate the correlation between S. apiospermum

serology and mycological findings of sputum samples

Patients

 Group of 499 pediatric and adult patients with cystic

fibrosis in Lyon, France

 256 children - median age 9 [0,17]  177 adults - median age 25 [18,53]  sex ratio =1.1  Inclusion criteria

• patient is a pediatric or adult CF patient
• patient has a serum sample collected during 2008 and

stored in the hospital mycological laboratory serum bank

 Exclusion criteria

• patient did not give his consent to the use of his serum

sample for the study

Materials and methods

Clinical and paraclinical data extracted from electronic file of each patient

 age, gender, age at CF diagnosis, CFTR genotype  in 2008 :

• weight, size
• respiratory functional parameters
• number of acute respiratory exacerbations
• duration of hospital stay
• courses of antibiotic and antifungal agents
• findings of sputum expectorations
• results of Aspergillus spp. serology

Materials and methods

Serum collection

 serums selected from a serum bank located in the

laboratory of mycology of Lyon University hospital

 serum used to determine Aspergillus spp. serology for

serological follow up of patients

 all samples collected during the same period (2008) and

• nly one per patient

 anonymisation of serums and transportation to Angers

Materials and methods

• S. apiospermum serology

Two serological techniques :

 ELISA using a mix of polysaccharide and protein

antigens extracted by mechanical disuruption using glass beads, and corresponding mainly to cytosolic antigens ELISA before and after adsorption with Aspergillus fumigatus antigen

 confirmatory technique by counterimmunoelectrophoresis

and/or western blot to identify specific bands

Perspectives

 present work : transversal epidemiological study of S.

apiospermum colonization in CF patients

 futur study : prospective cohort study of cystic fibrosis

patients with colonization of the respiratory tract and/or positive S. apiospermum serology

 study of the pathogenicity of S. apiospermum  guidelines for the management of patients with cystic

fibrosis colonized by S. apiospermum.

Acknowledgment

Contribution to the project



Centres de Ressources et de Compétences de la Mucoviscidose, Lyon



Groupe d’Etude des Interactions Hôte-Parasite, UPRES-EA 3142, Angers



Laboratoire paludisme, parasites du sang et mycologie médicale, Lyon



Pôle Information Médicale Evaluation Recherche - Lyon



Centre National de Référence des Mycoses et des Antifongiques, CNRS URA3012, Institut Pasteur, Paris, France.