Diagnosis and treatment of fungal keratitis. Part I

Abstract

Fungal keratitis (FK) is a difficult diagnostic challenge for ophthalmologists.
 The aim is to familiarize practicing physicians with the diagnostic algorithm worked out in the Ophthalmological Center of SPB City hospital No. 2 using modern research methods, and to assess the epidemiology of fungal keratitis in the North-West Region.
 Materials and methods. Patients underwent laboratory diagnostics (fluorescence microscopy of corneal scrapings from the cornea, сulture on Sabouraud agar and broth), confocal in vivo microscopy, optical coherence tomography.
 Results. During the period from 2007 to 2017, 41 cases of FK were identified in the City hospital No. 2, of which filamentous fungi were the causative agent in 32 cases (78%), yeast fungi — in 9 cases (22%). Our analysis included patients with fungal keratitis over the past three years, all of them underwent a full diagnostic cycle. Filamentous fungi were found among 12 of them (63%), yeast — in 7 (37%). Our data, considering the statistics of fungal keratitis in the North-West of Russia — a region with a high level of urbanization and industrialization, and located in the temperate zone — showed a predominance of filamentous fungi as pathogens (prevalence 1.3 times higher). Our scheme of keratitis diagnostics — confocal in vivo microscopy, OCT, fungal culture — is a reliable way to identify fungal pathogens in the cornea, and can be recommended for use in practical ophthalmology.

From Clinical Suspicion to Diagnosis: A Review of Diagnostic Approaches and Challenges in Fungal Keratitis

“…Optical coherence tomography (OCT) utilizes low-coherence interferometry to create cross-sectional images of the cornea, allowing ophthalmologists to assess its thickness and detect the presence of infiltrates [ 48 ]. In cases of fungal keratitis, OCT can detect changes in the cornea typical for the mycotic process [ 49 ]. In the initial phases of microbial keratitis, the cornea exhibits thickening in the infiltrated region.…”

Ethosomal Nanoformulations for Combinational Photothermal Therapy of Fungal Keratitis

“…Some of the standard treatment options include anti-fungal drugs, such as Amphotericin B, Fluconazole, or Natamycin for example, for several months, either orally or in topical application form and occasionally require surgical interventions for corneal transplantation. [4][5][6][7][8][9] Amphotericin B is known to be the first of its kind broad spectrum anti-fungal isolated from Streptomyces sp. and is reported to be highly efficient against Candida and Aspergillus infections.…”

“…Some of the standard treatment options include anti‐fungal drugs, such as Amphotericin B, Fluconazole, or Natamycin for example, for several months, either orally or in topical application form and occasionally require surgical interventions for corneal transplantation. [ 4–9 ]…”

Features of antifungal therapy during long-lasting infectious process: a clinical case of fungal keratitis and profile of antifungal sensitivity based on assessing biofilm formation

“…[10,11,14,15,16]. Грибковые кератиты, обусловленные данными микромицетами, регистрировались в основном в тропических и субтропичес-ких странах, преимущественно в агропромышленных регионах, но в последнее время в связи с активным использованием контактных линз часто выявляются и в регионах с умеренным климатом, в том числе и в России [1,2,4,17,36]. Основным предрасполагающим фактором для кератитов данной этиологии является механическая травма глаза, чаще всего обусловленная длительным использованием мягких контактных линз [33,35].…”

“…Грибы рода Fusarium имеют выраженную устойчивость к большинству противогрибковых препаратов. По своей природе они устойчивы к эхинокандинам, у некоторых видов выявлены высокие значения минимально ингибирующей концентрации (МИК) для противогрибковых препаратов группы азолов [1,36]. Необходимо учитывать тот факт, что грибы, колонизируя слизистые, могут существовать не только в виде планктонных форм, но и, прикрепляясь к поверхности, образовывать биопленки [3,5].…”