Investigation of fungal keratitis using mycological and molecular methods

Subject Areas : biology

Mojgan Saghazadeh ¹ (Assistant Professor, Department of Microbiology, Faculty of Science, Qom Branch, Islamic Azad University, Qom, Iran )
Neda Shirinabadi ² (MSc student, Department of Microbiology, Qom Branch, Islamic Azad University, Qom, Iran. )

Received: 2024-05-13 Accepted : 2024-07-08 Published : 2024-01-31

Keywords: fungal keratitis, mycological method, confocal microscopy, culture, PCR, cornea, eye diseases.,

Abstract :

Purpose: Fungal keratitis is a general term for a fungal disease of the cornea and can be caused by a wide variety of fungi. Keratitis is one of the causes of blindness worldwide. In this regard, the aim of the present research is to achieve an accurate and correct method in the diagnosis of fungal keratitis.

Materials and methods: From all patients with keratitis who referred to the Central Eye Bank of Iran from May 1394 to June 1395, in addition to direct examination and culture of a corneal chip sample, the diagnosis was first made by confocal scanning of the cornea, and the sensitivity and specificity of the diagnosis obtained from confocal scanning with Direct experiment and cultivation were compared. Then, using the colonyPCR method, PCR was performed from the colonies of Aspergillus and Fusarium fungi without DNA extraction, with the general primers of fungi (ITS1,4) and the specific primer of Aspergillus genus (ASPf1).

Findings: Out of 366 patients clinically suspected of having infectious keratitis, direct test and confocal scan results were positive in 17 patients and culture was
positive in 13 cases. 47.06% of the patients were workers. Fusarium genus was the most isolated (47.06%). The rest included Aspergillus (17.65%), Microsporum (5.88%) and Penicillium (5.88%).

Conclusion: Since the delay in the treatment of fungal keratitis causes corneal opacity, reduced vision and absolute blindness, timely diagnosis and rapid treatment of fungal keratitis is necessary.

 

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