Herpes Simplex Keratitis

Herpes simplex keratitis (HSK) is a viral infection of the cornea caused by the herpes simplex virus (HSV). It is a common cause of ocular morbidity and can lead to significant visual impairment if left untreated or poorly managed.

Causes and Risk Factors

Herpes simplex keratitis is caused by the herpes simplex virus, which is highly contagious and can be spread through direct contact with an infected person's secretions, such as tears, saliva, or skin lesions. The risk factors for developing HSK include:

• Previous history of HSV infection
• Immunocompromised state, such as HIV/AIDS or taking immunosuppressive medications
• History of ocular trauma or surgery
• Contact lens wear

Symptoms and Signs

The symptoms and signs of herpes simplex keratitis may include:

• Redness and inflammation of the eye
• Pain or discomfort in the eye
• Blurred vision
• Sensitivity to light
• Excessive tearing or discharge
• A characteristic dendritic ulcer on the cornea, which can be seen with fluorescein staining

Diagnosis

The diagnosis of herpes simplex keratitis is typically made based on a combination of clinical presentation and diagnostic tests, including:

• Slit-lamp examination to visualize the cornea and anterior segment
• Fluorescein staining to detect corneal ulcers or epithelial defects
• Culture or PCR (polymerase chain reaction) testing to confirm the presence of HSV

Treatment

The treatment of herpes simplex keratitis typically involves a combination of antiviral medications, such as:

• Topical antiviral agents, such as trifluridine or ganciclovir
• Oral antiviral agents, such as acyclovir or valacyclovir

In addition to antiviral medications, supportive care may include:

• Pain management with topical anesthetics or oral analgesics
• Anti-inflammatory medications to reduce inflammation and prevent scarring
• Lubricating eye drops to promote healing and comfort

Complications and Prognosis

If left untreated or poorly managed, herpes simplex keratitis can lead to significant complications, including:

• Corneal scarring and vision loss
• Recurrent episodes of HSK
• Increased risk of secondary bacterial or fungal infections

The prognosis for herpes simplex keratitis is generally good with prompt and effective treatment, but the condition can be recurrent and may require long-term management to prevent complications.