Scedosporium species in soils from various biomes in Northwestern Morocco.

Abdelmounaim Mouhajir,Marie-Elisabeth Bougnoux,Rachid Zouhair,Rachid Bouabid,Jean-Philippe Bouchara,Abdessamad Kobi,Wilfried Poirier,Elkahkahi Rahal,Sandrine Giraud,Cécile Angebault

doi:10.1371/journal.pone.0228897

Abstract

Scedosporium species are opportunistic pathogens causing various infections, including disseminated infections in severely immunocompromised patients. Preventive measures aiming to reduce the risk of exposure to these fungi require a better knowledge on their ecology and on the sources of contamination of the patients. In this context, 99 soil samples from the Rabat-Sale-Kenitra and Fez-Meknes regions in Morocco were analyzed. Samples were inoculated on the highly selective Scedo-Select III culture medium, and seven chemical parameters of the soils were measured. Scedosporium species were detected in 48 of the samples, with the highest density in soils from wastewater treatment plants and landfills, followed by those from roadsides and polluted riverbanks, thus confirming the impact of human activities on their ecology. Scedosporium apiospermum was the most common species, followed by S. boydii and S. aurantiacum. Analysis of the chemical parameters of the soils revealed the presence of Scedosporium species was mainly associated with a moderate electrical conductivity, a pH range of 7.0 to 7.6, a nutrient-rich content and a moderate phosphorus amount. Thereby, these results demonstrated the relatively high occurrence of Scedosporium in Morocco and highlighted the impact of phosphorus content on their ecology.

Highlights

Living as saprotrophic organisms, members of the ascomycete genus Scedosporium may cause in human a wide variety of infections affecting both the immunocompetent and immunocompromised individuals [1,2]
The chronic colonization of the airways by Scedosporium species should not be disregarded since it may lead to bronchitis and allergic bronchopulmonary mycoses, and to severe and often fatal disseminated infections in case of immunodeficiency, after lung transplantation which remains the ultimate treatment of these patients [4,5,6,7]
The impact of human activities on the detection of Scedosporium species was evidenced by determination of the number of Scedosporium-culture positive samples in the different biomes studied (Fig 1A and 1B). 90% and 75% of the samples from banks of polluted rivers and from wastewater treatment plants (WWTP) and landfills respectively, were culture-positive for these fungi

Summary

Introduction

Living as saprotrophic organisms, members of the ascomycete genus Scedosporium may cause in human a wide variety of infections affecting both the immunocompetent and immunocompromised individuals [1,2]. Ecology of Scedosporium species in Morocco immunosuppressive therapy for solid organ or bone marrow transplantation [3]. Some filamentous fungi may be encountered, including species of the genus Scedosporium which ranks the second among the filamentous fungi colonizing the CF lungs after Aspergillus fumigatus. The chronic colonization of the airways by Scedosporium species should not be disregarded since it may lead to bronchitis and allergic bronchopulmonary mycoses, and to severe and often fatal disseminated infections in case of immunodeficiency, after lung transplantation which remains the ultimate treatment of these patients [4,5,6,7]. A better knowledge on the ecology of these fungi is required in order to identify the potential sources of contamination and to define preventive measures aiming to reduce the risk of contamination of the patients

Methods

Results

Conclusion