Herpes Eye Infections
Herpes Eye Infections
The most common cause of herpes eye infection is herpes simplex virus. Also it can be caused by varicella zoster virus.
Types of Herpes Simplex Virus
1- HSV type 1 which commonly will cause infection above the waist especially in area supplied by cranial nerve V which is called Trigeminal nerve but can also cause infection below waist.
2- HSV type 2 which commonly cause infection below waist( genital area) but also can cause infection above waist.
Primary Herpetic Eye Infections
Most of the people had primary infection with this virus but most of them without clinical significant. The virus after the primary infection will lie in a special neurons collection called ganglia. Almost 100% of population above 65 will have positive laboratory test for herpes virus. Most of the time the primary infection will be manifested as mild upper respiratory tract infection which is self limited and will heal by itself.
Blepharoconjunctivitis is also another form of primary infection of herpes virus. It is characteristic by vesicles on eyelid or skin around it and also by conjunctivitis with red eye and discharge.
Sometimes corneal epithelial defects can occur but it will be uncommon to have infection of corneal stroma. This form of primary infection is self limited in most of the cases but sometimes especially in severe cases antiviral medications can be applied.
Recurrent Herpetic Eye Infection
After primary infection, the virus will transfer through the neuron to ganglia and settle there silently with no symptoms or signs until they reactivated again, causing recurrent infections which are clinically signification. Recurrent herpes infection can affect any part of the eye such as eyelid, conjunctiva, cornea, iris and retina.
There are many reasons for this reactivation but the most common are immunodeficiency diseases such as HIV and chemotherapy. Other factors that may cause reactivation are stress, malnutrition, UV light exposure and infection.
Forms of Recurrent Herpes Eye Infection
2- Herpetic keratitis
Herpetic keratitis is a form of recurrent herpes infection and can be divided into two main categories epithelial keratitis and stromal keratitis. Read more about Herpetic keratitis.
It means inflammation of both iris and ciliary body. Read more about Iridocyclitis