Journal of Neuroinfectious Diseases
Open Access

Keratitis is an inflammatory condition of the cornea, the transparent front part of the eye that covers the iris and pupil. This condition can lead to pain, redness, blurred vision, excessive tearing, and, in severe cases, vision loss if not treated promptly. Keratitis can be caused by infections (bacterial, viral, fungal, or parasitic), non-infectious factors such as eye trauma, dry eyes, or prolonged contact lens wear. Understanding the causes, symptoms, diagnosis, treatment, and prevention of keratitis is crucial for maintaining good ocular health and preventing complications. Infectious keratitis can result from bacterial, viral, fungal, or parasitic infections, often exacerbated by improper contact lens use, corneal injuries, or weakened immune function. Non-infectious keratitis may arise due to dry eye syndrome, prolonged contact lens wear, excessive exposure to UV light, chemical irritants, or physical trauma. Symptoms of keratitis include eye redness, pain, blurred vision, light sensitivity, excessive tearing, and a sensation of a foreign body in the eye. Severe cases can lead to corneal ulcers and permanent scarring, necessitating immediate medical intervention. Early diagnosis through a comprehensive eye examination, including slit-lamp microscopy and microbial cultures, is crucial for determining the appropriate treatment. Treatment depends on the underlying cause and may include antibiotic, antiviral, antifungal, or anti-inflammatory eye drops, along with supportive measures like artificial tears or bandage contact lenses [1,2]. Preventive measures such as proper contact lens hygiene, wearing protective eyewear, and seeking prompt medical attention for eye infections can significantly reduce the risk of keratitis. With timely intervention and adherence to preventive strategies, most cases of keratitis can be effectively managed, preserving long-term vision health [3,4].

Discussion

Keratitis is a multifaceted ocular condition that presents with various etiologies, clinical manifestations, and treatment modalities. Understanding the pathophysiology and risk factors associated with keratitis is crucial for effective management.

One of the most common risk factors is contact lens wear. Poor hygiene practices, such as wearing lenses overnight or not disinfecting them properly, significantly increase the risk of bacterial or fungal infections. Similarly, individuals exposed to contaminated water, such as swimming pools or hot tubs, are at a heightened risk of developing Acanthamoeba keratitis, a severe and challenging-to-treat parasitic infection.

The clinical presentation of keratitis varies depending on the causative agent. Bacterial keratitis typically presents with rapid onset pain, purulent discharge, and corneal infiltrates. Viral keratitis, often caused by the herpes simplex virus, leads to recurrent episodes of dendritic ulcers and corneal inflammation. Fungal keratitis, on the other hand, has a more insidious onset with feathery-edged infiltrates and satellite lesions, making diagnosis and treatment more challenging [5].

Treatment strategies depend on the etiology. Bacterial keratitis often requires aggressive antibiotic therapy, with fortified eye drops administered hourly. Viral keratitis necessitates antiviral agents like acyclovir, while fungal infections demand prolonged antifungal treatment, sometimes requiring surgical intervention in severe cases. Non-infectious keratitis, such as exposure keratitis due to incomplete eyelid closure, may be managed with lubricating eye drops and protective eyewear [6,7].

The prognosis for keratitis largely depends on early detection and timely intervention. Delayed treatment can result in complications such as corneal scarring, perforation, or endophthalmitis, ultimately affecting vision. Awareness, preventive measures, and adherence to proper ocular hygiene play a vital role in minimizing the incidence and severity of keratitis [8].

Causes of keratitis

Keratitis can be classified into two broad categories: infectious and non-infectious.

Infectious keratitis

Bacterial keratitis: Typically caused by Staphylococcus aureus, Pseudomonas aeruginosa, or Streptococcus pneumoniae, bacterial keratitis is commonly linked to contact lens use, corneal injuries, or compromised immune function.

Viral keratitis: The most common viral cause is the herpes simplex virus (HSV), which can cause recurrent infections. Varicella-zoster virus (which causes shingles) can also affect the cornea [9].

Fungal keratitis: Caused by fungi like Fusarium, Aspergillus, or Candida species, this type is often associated with trauma involving plant material or contaminated water exposure.

Parasitic Keratitis: Acanthamoeba keratitis, though rare, is a serious condition often linked to improper contact lens hygiene or exposure to contaminated water sources.

Non-Infectious Keratitis

Exposure keratitis: Occurs due to incomplete eyelid closure, leading to corneal drying and damage.

Allergic keratitis: Can result from allergic reactions to environmental allergens or contact lens solutions.

Traumatic keratitis: Mechanical injuries, chemical burns, or foreign body entry can cause corneal inflammation.

Dry eye-associated keratitis: Severe dry eye syndrome can lead to corneal irritation and damage over time.

Treatment of keratitis

Treatment depends on the underlying cause:

Infectious keratitis treatment

Bacterial keratitis: Treated with broad-spectrum or targeted antibiotic eye drops, often administered frequently to control infection.

Viral keratitis: Antiviral medications such as acyclovir or ganciclovir are used for herpes simplex or varicella-zoster infections.

Fungal keratitis: Requires antifungal eye drops like natamycin or oral antifungal medications for severe cases.

Parasitic keratitis: Acanthamoeba keratitis is treated with antiseptic eye drops, but it requires prolonged therapy due to the parasite's resistance [10].

Non-infectious keratitis treatment

Artificial tears and lubricants: Used for dry eye-associated keratitis.

Steroid eye drops: May be prescribed for inflammation but should be used cautiously to avoid worsening infections.

Bandage contact lenses: Help protect the cornea in cases of exposure keratitis or persistent epithelial defects.

Surgical interventions: Corneal debridement or, in severe cases, corneal transplants may be necessary for irreversible damage.

Conclusion

Keratitis is a potentially serious condition that can lead to vision impairment if not diagnosed and treated promptly. It can arise from various infectious and non-infectious causes, making accurate diagnosis essential for effective management. While treatments range from topical medications to surgical interventions, prevention remains key through proper eye care and hygiene. Increased awareness, early detection, and prompt medical intervention can help minimize complications and preserve vision health. Advancements in medical technology, including improved diagnostic tools and innovative treatment modalities, continue to enhance the prognosis of keratitis. Confocal microscopy and molecular testing allow for quicker and more accurate pathogen identification, enabling targeted therapy. The development of new antimicrobial agents and anti-inflammatory treatments offers hope for better outcomes, particularly in resistant or severe cases. Ultimately, a multidisciplinary approach involving ophthalmologists, optometrists, and primary care providers is essential to ensuring effective prevention, timely diagnosis, and appropriate treatment of keratitis.

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