Fungal Keratitis. Part 2. Diagnosis and Treatment

Abstract

The problem of diagnosis and treatment of fungal keratitis (FK) is very acute. Due to the slow development of clinical features and the absence of clear pathognomonic signs, this disease is characterized by a late start of the introduction of adequate etiotropic therapy. Often this leads to the development of large corneal defects requiring surgical intervention. Diagnostic methods are divided into invasive and non-invasive. Invasive methods include the study of scrapings from the surface of the cornea from the site of ulceration, biopsy of the corneal stroma or moisture of the anterior chamber using microscopic, cultural methods or polymerase chain reaction (PCR). Non-invasive techniques include confocal microscopy and optical coherence tomography of the anterior segment. They allow you to dynamically monitor the course of the pathological process and the response to ongoing therapy. Promising methods are also the detection of (1,3)-β-D-glucans in tears, the detection of the pathogen using MALDI-TOF MS. The gold standard for the treatment of FK in the world is the topical application of 5 % Natamycin (approved by the FDA, but not available in Russia). Fluconazole, Voriconazole and Amphotericin B, available in Russia, are also widely used, but their topical use is possible only in off label format. In the presence of hypopyon or an increase in the size and depth of the infiltrate, despite ongoing treatment, immediate surgical treatment is required in order to preserve the integrity of the eyeball. Such treatments include penetrating keratoplasty, anterior lamellar keratoplasty, amniotic membrane transplantation, conjunctival flaps, corneal collagen cross-linking (with unproven efficacy), and argon laser. A promising method for the treatment of FK can be the use of Ag(10 %):InP/ZnS MPA quantum dots as monotherapy or as a bioconjugate with known antifungal drugs.