Fungal diseases and infections can be divided into two categories: superficial and invasive. Superficial infections are associated with colonization of the external auditory meatus and middle ear. Superficial non-invasive infections are manifested with minimal symptoms such as ear itching, discharge, unexpressed pain, this condition is often found in patients with impaired immunity after local or systemic antibacterial therapy with a decrease in the normal microflora of the middle ear and the skin of the external auditory meatus.    

The external auditory meatus and the tympanic membrane are most susceptible to the non-invasive fungal process , and the tympanic cavity may also be involved. Candida and Aspergillus are the most common pathogens of the fungal process. Otoscopy reveals pathological contents of black or white. Treatment includes ear toilet followed by topical antifungal medications such as drops of 1% clotrimazole or lotrimin / triamcinolone ointment.  

Invasive fungal infection usually occurs in immunocompromised patients. Cryptococcosis is usually manifested by neurological symptoms: headache, confusion, depression, and agitation during germination in the temporal bone in the terminal stage. 

Aspergillosis most often begins as a pulmonary infection with the direct entry of fungi through the auditory tube into the middle ear. Mucormycosis affects the paranasal sinuses and orbit and proceeds with lightning speed. All three types of fungus invasive infections of the external auditory canal, middle ear or mastoid process are quite rare in immunocompromised patients. 

The clinical picture includes severe acute pain with discharge from the ear, bleeding from the ear, sensorineural or conductive hearing loss. Dizziness and paresis of the facial nerve may be present. With invasive fungal otitis media, the most common pathogen are fungi of the genus Mucor, then Aspergillus and Cryptococcus. Treatment includes surgical treatment and the use of systemic antifungal drugs such as amphotericin-B. Invasive fungal infections are associated with severe complications and high mortality.  

Histopathologically, fungal infections can be identified by their characteristic appearance. Candida is dimorphic, that is, the fungus exists in two forms, unicellular and filamentous forms are more common, but candida can exist in the form of a pseudohyphus. 

Cryptococcus is a unicellular, filamentous and spherical fungus. Aspergillus is a septum hyphae with partitions. Mucor also forms island hyphae, but without partitions. Fungal infections can induce the development of granulomas. A feature of fungal infections is vascular thrombosis and widespread tissue necrosis, never manifested in superficial infections. 

Invasive fungal infections of the temporal bone involve the middle ear, submucosal layer and eardrum, and also lead to nerve infiltration in the internal auditory canal, membranous labyrinth, Rosenthal canal with loss of neurons and occlusion of the labyrinth arteries.

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