Fungal keratitis

Fungal keratitis develops rarely and is caused by mold, radiant and yeast fungi.

Infection occurs after minor damage to the cornea, more often in rural areas. Fungi can be transferred from skin lesions to the eye. The first symptoms appear quickly - already on the 2nd-3rd day after the injury. The inflammatory focus is often localized in the superficial layers.

Fungi can penetrate into the deep layers together with the wounding object. If a foreign body remains in the cornea for a long period of time, a creeping ulcer with all its characteristic symptoms and consequences can develop.

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Symptoms of Fungal Keratitis

Symptoms of fungal corneal lesions have characteristic features. The appearance of the infiltrate alone can suggest a fungal nature of the disease. Subjective symptoms and pericorneal injection of vessels are weakly expressed in the presence of a fairly large lesion in the cornea. The inflammation focus is typically white or yellowish in color and has clear boundaries. Its surface is dry, the infiltration zone resembles a salt incrustation, sometimes it is bumpy or cheesy, as if it consists of grains and slightly protrudes above the surface of the cornea. The focus is usually surrounded by a limiting ridge of infiltration. The clinical picture may seem to have frozen for several days or even 1-2 weeks. However, the changes gradually increase. The ridge of infiltration around the focus begins to collapse, the corneal tissue becomes necrotic. At this time, the entire white, dry-looking focus can separate on its own or be easily removed with a scraper. A depression opens under it, which slowly epithelializes and is subsequently replaced by a leukoma. Fungal keratitis is characterized by the absence of neovascularization. Creeping ulcers of fungal origin are usually combined with hypopyon. Perforations of the cornea with the formation of a rough leukoma fused with the iris are also possible, although this is not typical for fungal keratitis. In the material obtained from the inflammation focus, a dense interweaving of mold threads or druses of the radiant fungus is found during microscopic examination.

Diagnosis of fungal keratitis

Despite the fact that in typical cases the clinical picture of fungal keratitis has quite noticeable features, reliable etiologic diagnostics is not always simple, since along with the characteristic ones, other manifestations of fungal keratitis are also observed. In addition, fungi can complicate the course of bacterial keratitis in the necrotic stage of inflammation. They multiply well in tissues in which oxidative processes are weakly expressed. In this regard, in all cases of torpid keratitis, it is necessary to conduct a study of necrotic material for the presence of fungi. If fungal keratitis is suspected, steroids are not used, since they activate the growth of fungi. The curdy central area in the inflammation focus is removed with a scraper, the bottom and edges are cleaned with a sharp spoon, then stewed with a 5% alcohol solution of iodine. The removed material is subjected to examination.

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Treatment of fungal keratitis

In the treatment of fungal keratitis, intraconazole or ketoconazole, nystatin or other drugs to which a specific type of fungi is sensitive are prescribed orally. Instillations of amphotericin, nystatin, sulfadimizin and actinolysate (for actinomycosis) are used locally. Intraconazole is prescribed 200 mg orally once a day for 21 days. In order to prevent the development of secondary infection, sulfonamides in drops, eye ointments with antibiotics are used. In case of long-term persistent fungal keratitis with the location of the inflammation focus in the central part of the cornea, therapeutic layered keratoplasty is indicated.