To illustrate by this case report that Acremonium must now be considered as a differential diagnosis in cases of maxillary fungus balls.

Seventy-seven-year-old woman consulted for persistent pain of the right maxillary sinus, with rhinorrhea and nocturnal coughing. Computed tomography (CT) of the sinuses showed a heterogeneous opacification of the right maxillary sinus with well-defined hyperdense foci suggesting aspergillosis. She underwent a middle meatus antrectomy by an endonasal approach. Six months after the surgery, her symptoms were gone and had not recurred. Mycological examination found Acremonium.

Acremonium is a genus of saprobic fungi that rarely cause disease in humans. Infection with Acremonium has recently been described in immunocompromised patients. We describe the first case of fungal maxillary sinusitis caused by Acremonium in an immunocompetent person. Clinically and radiologically, the initial diagnosis was aspergillosis. Acremonium must be considered together with aspergillosis in all situations of fungus ball chronic sinusitis.