Inflammatory processes in the cornea can be caused by endogenous and exogenous keratitis. In the first case, internal processes lead to their development. Exogenous keratitis is provoked by external factors. An ophthalmologist should identify the causes that led to the development of the disease, and establish an accurate diagnosis.
Problem description
Herpetic keratitis is an infectious disease that affects the cornea of the eye. It can be caused by one of 5 types of herpes viruses. The most common is HSV-1. This is the herpes simplex virus type 1, antibodies to it are found in 90% of the population. It usually affects the upper body. The face suffers the most.
But the cause of herpes keratitis can also be:
- herpes simplex virus type 2;
- herpes zoster (it causes shingles and chickenpox);
- Epstein-Barr virus;
- cytomegalovirus.
But most often it is HSV-1 that affects the eyes.
Herpetic keratitischaracterized by the fact that the shell of the eye becomes cloudy. As a result of such a lesion, a person's vision deteriorates significantly, he may even go blind.
Symptoms of disease
The virus can affect both adults and children who are under 5 years old. The primary symptoms of its appearance are:
- lacrimation;
- blepharospasm (a condition in which the eyelids involuntarily close spasmodically);
- photophobia.
But this is not yet a complete list of signs by which herpetic keratitis can be identified. Symptoms of the disease can be:
- redness of the eye shell;
- feeling of being hit by a foreign body;
- burning;
- pain in the eye.
In a primary infection, blisters may appear on the eyelid and conjunctiva. It heals without scarring. The cornea in the primary lesion remains intact in most cases.
Reactivation of the virus causes periodic herpetic keratitis. The history of the disease, the forms of the disease are important for further diagnosis and determination of treatment tactics. In a latent form, the virus is stored in the sensory ganglion. When reactivated, it is transported to the nerve endings, after which the infection of the eyeball occurs.
Disease forms
Depending on the clinical picture, there are several types of lesions. The classic herpes disease is manifested by branching ulcers on the cornea. This is truecalled epithelial herpetic keratitis. It affects only the outer layer of the cornea, which consists of flat epithelial cells.
Specialists identify a tree-like and geographical type of the disease. The diagnosis is based on how widespread the inflammatory reaction is. It is also important how much corneal tissue is destroyed.
Doctors diagnose arborescent herpetic keratitis when corneal ulcers look like tree branches. The situation is a little worse if the doctor speaks of a geographical lesion. This means that the cornea is damaged more seriously. The areas of destroyed epithelium are significant, and their outlines resemble the schematic representation of continents on maps.
Stromal keratitis is also called discoid. In this disease, it is not the outer layer of the cornea that is affected, but its inner surface - the stroma. The most dangerous type is stromal necrotizing keratitis. In this type of disease, inflammation develops rapidly. It can cause destruction of corneal tissue. This can eventually lead to blindness.
The first two forms of herpetic keratitis (tree and geographic) with adequate treatment end in complete recovery.
Diagnosis
To prevent the development of complications, it is necessary to contact an ophthalmologist when the first signs of the disease appear. He can diagnose and choose the most appropriate treatment.
The doctor assesses the patient's condition, looks at the manifestationsdiseases. It also measures intraocular pressure. To determine the degree of damage, it is necessary to drip fluorescein into the eyes. This is a special reagent that is visible under ultraviolet light. It can be used to assess how herpetic keratitis has damaged the surface of the cornea.
Also, diagnostics allows you to identify exactly which layers the virus has infected. Depending on this, the tactics of treatment will be determined.
Laboratory studies
In most cases, the clinical picture of keratitis is pronounced. But there are situations when even with the help of special tests it is not possible to accurately diagnose. Then a laboratory test may be required. It is also necessary for the defeat of the herpes simplex virus in newborns.
For its implementation, swabs can be taken from the cornea. But such a study is insensitive. DNA testing will be more informative. However, this is a rather expensive examination, so it is used extremely rarely. Serological tests are informative in the primary lesion: they show the growth of antibodies. But when the virus reactivates, they become useless.
Causes of disease
Herpetic keratitis of the eye is an infectious disease. With the primary lesion with the herpes simplex virus in most cases, no symptoms appear. Sometimes there may be characteristic blisters around the lips.
Once in the body, the virus remains forever in the cells of the trigeminal nerve. He is in a dormant state. Butreactivation is possible from time to time. In this case, the pathogen begins to actively multiply. Viruses can travel to the tissues of the face and eyes.
Herpetic keratitis, as a rule, appears precisely after the reactivation of this virus. Once on the cornea of the eye, the virus continues to multiply.
But the destruction of tissues begins due to the reaction of the immune system. After all, it is responsible for the development of the inflammatory response. Immune cells can recognize viruses and destroy tissues that are infected with them. Sometimes the damage from the immune response is much stronger than from the action of the virus itself.
What causes the virus to reactivate?
Almost 90% of people are carriers of the herpes simplex virus. But not everyone gets herpetic keratitis. Researchers believe that the infection may develop under the influence of certain factors and conditions that affect the body.
For a long time, doctors believed that the virus is activated on the background of stress. But a study of a group of people refuted this assumption. Therefore, doctors cannot say for sure what causes this type of keratitis.
But it has been established that those people who have undergone various eye surgeries are more susceptible to this disease. It can be laser vision correction, cataract removal, glaucoma treatment, corneal transplant.
Treatment tactics
Necessary therapy can be prescribed only after examination by an ophthalmologist. He must confirm the diagnosis of "herpetic keratitis of the eye." Treatment alsoselects a specialist.
If herpes affected only the eyelids, then it will be enough just to use the tablets "Acyclovir" or "Valacyclovir". You need to drink them for 5 days. For the treatment of epithelial keratitis, you will need to purchase an eye gel that contains 0.15% gancilovir or drops with 1% trifluridine. Acyclovir ointment may also be prescribed. It must be laid behind the lower eyelid at least 5 times a day.
Treatment continues until complete healing. In some cases, it is enough to take only Acyclovir tablets. If such treatment is ineffective, then interferon drops are used.
Stromal keratitis is more difficult to treat. In the first two days, tablets "Acyclovir" (2 g per day) or "Valacyclovir" (1 g per day) are prescribed. In this dosage, they must be drunk for up to 2 weeks. If the disease does not progress in the first two days of the course, then in the future it is recommended to use drops with dexamethasone 0.1%. Initially, they are dripped up to 8 times a day, but gradually the frequency of use is reduced every 3-6 days by 1 drop. This treatment should continue for several months.
