[Invasive acute sinusitis by Exserohilum rostratum in a patient with medullary relapse of acute lymphoblastic leukemia].

Invasive fungal infection has increased in frequency over the last decade, with fungal sinusitis becoming more frequent. The fungi of the genus Exserohilum (family Pleosporaceae, order Pleosporales) are filamentous and dematiaceous of ubiquitous location. It is an emerging pathogen, which in most cases produces a systemic infection that mainly affects the paranasal sinuses and lungs.