Fungal keratitis is a severe corneal infection that can lead to significant vision impairment and potential blindness if not properly diagnosed and treated. This condition occurs when fungi invade the cornea, causing inflammation and damage to corneal tissue. The infection commonly affects individuals in tropical and subtropical regions, particularly those involved in agricultural work. Common risk factors include:

• Trauma to the eye, especially from plant material
• Extended contact lens wear
• Pre-existing corneal conditions
• Compromised immune system

Symptoms of Fungal Keratitis

Common symptoms of fungal keratitis include:

• Severe eye pain and irritation
• Increased light sensitivity (photophobia)
• Blurred or decreased vision
• Excessive tearing and discharge
• Redness of the eye
• Foreign body sensation

The infection typically presents with a gray-white infiltrate that has feathery or irregular borders. As the condition progresses, patients may develop:

• Satellite lesions around the main infiltrate
• Corneal ulceration
• Hypopyon (accumulation of white blood cells in the anterior chamber)
• Endothelial plaque formation

Early symptoms can be subtle and may not be evident until an advanced stage, making diagnosis challenging. The infection can spread deep into the corneal stroma, causing significant inflammation and tissue damage. Without proper treatment, the condition can lead to corneal scarring, perforation, and permanent vision impairment.

In severe cases, patients may experience: Deep corneal infiltration, Corneal perforation, Secondary glaucoma, Anterior chamber inflammation and Severe visual loss.

Causes of Fungal Keratitis

The causes of fungal keratitis are diverse and often linked to specific environmental and individual risk factors. The primary causative organisms in fungal keratitis are: Candida species, Fusarium species and Aspergillus species

Early symptoms may include:

• Eye pain
• Reduced vision
• Light sensitivity
• Redness
• Tearing

Diagnosis can be challenging as the initial presentation may resemble other types of keratitis. Clinical examination typically reveals corneal ulceration with feathery borders and satellite lesions. Proper diagnosis requires corneal scraping for microscopy and culture to identify the specific fungal pathogen.

Without prompt and appropriate treatment, fungal keratitis can progress rapidly, leading to corneal scarring and permanent vision loss. An estimated 1,051,787 to 1,480,916 eyes are affected annually worldwide, with 8-11% of patients requiring removal of the eye. There can be multiple causesleading to infection:

Direct Corneal Trauma

Injury to the cornea from plant material or organic matter is a primary cause, particularly in agricultural workers and those in rural settings. Vegetative matter trauma accounts for approximately 45.3% of fungal keratitis cases.

Contact Lens-Related Issues

Improper contact lens use and maintenance can lead to fungal keratitis. Extended wear of contact lenses, poor hygiene practices, and incorrect cleaning methods increase infection risk.

Environmental Factors

Living in tropical and subtropical regions increases exposure to fungal organisms. Agricultural workers and construction workers face higher risks due to exposure to organic materials and soil containing fungal spores.

Medical Conditions

• Chronic ocular surface diseases
• Diabetes mellitus
• Systemic immune deficiency conditions
• Previous eye surgeries or corneal transplants

The improper use of broad-spectrum antibiotics and corticosteroids can increase susceptibility to fungal infections. Prolonged topical steroid use may suppress local immune responses and create favorable conditions for fungal growth.

Occupational Hazards

Certain professions carry higher risks of developing fungal keratitis: Agricultural workers, Construction workers, Gardeners and Individuals working with organic materials.

Treatment of Fungal Keratitis

Treatment of fungal keratitis requires a comprehensive approach, combining antifungal medications with careful monitoring. The success of treatment depends on early diagnosis and appropriate intervention.

Medical Treatment

• Topical antifungal medications (natamycin 5% or amphotericin B)
• Systemic antifungal drugs for deep infections
• Regular debridement of necrotic tissue
• Supportive therapy to manage inflammation and pain

Surgical Interventions

In severe cases where medical treatment is insufficient, surgical procedures may be necessary:

• Therapeutic penetrating keratoplasty
• Corneal transplantation
• Conjunctival flap surgery

Prevention Strategies

Prevention is essential, particularly for high-risk individuals such as agricultural workers, construction workers, and gardeners who are frequently exposed to organic materials and soil containing fungal spores.

• Proper eye protection when working with organic materials
• Regular contact lens hygiene and proper maintenance
• Immediate medical attention following eye trauma
• Regular eye examinations for individuals with compromised immune systems

Monitoring and Follow-up

Treatment progress requires careful monitoring through:

• Regular slit-lamp examinations
• Assessment of corneal healing
• Evaluation of visual acuity
• Monitoring for potential complications

Treatment Duration

The duration of treatment varies depending on:

• Severity of infection
• Type of fungal organism
• Patient response to therapy
• Presence of complications

Treatment typically continues for several weeks to months, and regular follow-up is essential to ensure complete resolution of the infection and prevent recurrence.

Conclusion

Fungal keratitis remains a serious eye condition that requires immediate medical attention and proper treatment to prevent vision loss. Understanding the risk factors, recognizing early symptoms, and seeking prompt medical care are essential for better outcomes. With appropriate antifungal therapy, careful monitoring, and preventive measures, most patients can recover successfully. However, the condition’s severity underscores the importance of protective eyewear in high-risk environments and maintaining good eye hygiene practices. Through continued awareness, proper eye care, and timely intervention, we can reduce the incidence and impact of fungal keratitis on global eye health.