Keratitis: symptoms, treatment and prevention

Introduction

Keratitis is a general inflammation of the cornea. Although often infectious in nature, keratitis can also be caused by surgical trauma or favored by the penetration of an object into the eye.

Although it may ideally affect anyone, infectious keratitis occurs more often in severely immunocompromised patients (eg those affected by the HIV virus) and weakened; the

Symptoms

The keratitis is always symptomatic: in fact, most of the time the observable signs and the symptoms perceived at the ocular level manifest themselves in a rather glaring way.

In most cases, keratitis begins with a strong rapid-onset ocular pain, accompanied by light intolerance (photophobia), hyperemia (red eyes) and abundant watery eyes. Alongside these symptoms, the patient suffering from keratitis often complains of an alteration of vision (blurred vision) and the perception of a foreign body inside the eye. Sometimes, keratitis can cause pain that prevents the patient from opening his eyes.

The severity of signs and symptoms of keratitis depends on the cause, the depth of the damage, the structural conditions of the cornea and the immune status of the host.

The characteristic signs of corneal infections make differential diagnosis difficult because most infectious keratitis manifests itself with almost the same symptoms.

Diagnosis

The diagnosis of a presumed keratitis begins with the anamnesis, that is with the collection of the symptoms reported by the patient.

Next, we proceed with an external ocular diagnosis (eye test), in which the ophthalmologist observes the appearance of the patient's eyes, the conjunctiva, the eyelids, the corneal sensitivity and the lacrimal apparatus. The analysis of the different ocular structures is often performed with an instrument called a slit lamp, consisting of a light source and a magnifying glass. This instrument uses intense light to illuminate the iris, cornea, crystalline and the space between the cornea and the lens.

But what can be evaluated with the use of the slit lamp? The table shows the ocular characteristics that can be evaluated with this tool.

The confirmation of a presumed infectious origin of keratitis and the identification of the causative organism can be obtained exclusively through specific microbiological tests, which include cultures and GRAM staining. By sending the analyzes to the laboratory a tear sample or some corneal cells it is possible to go back to the triggering cause, thus establishing a specific cure relatively quickly.

Care

The cure for keratitis must be carefully evaluated based on the causative agent that caused it. Although the drugs used to treat the different forms of keratitis are different, the objectives to be pursued are almost the same:

1. Remove the causative agent
2. Check the inflammation
3. Promote re-epithelialization (regrowth of the damaged corneal epithelium)

NON-INFECTIOUS KERATITIS

To treat traumatic keratitis dependent on the clumsy use of contact lenses, it is necessary to administer antibiotic ophthalmic ointments, essential to prevent any - if possible - bacterial ocular infection.

The treatment of non-infectious keratitis related to prolonged exposure to UV light involves the use of short-acting cycloplegic drugs (capable of inducing a temporary block of the parasympathetic nerves to favor dilation of the pupil and release the ciliary muscle). Sometimes, antibiotic ophthalmic ointments (to prevent possible infections) and eye bandaging may be prescribed for 24 hours.

If the inflammation of the cornea is related to an abuse of ophthalmic corticosteroid drugs, it is generally sufficient to interrupt the therapy to restore the state of health of the eye; however, medical supervision is recommended.

The instillation of artificial tears in the form of eye drops is indicated to promote ocular lubrication in the context of keratitis related to dry eye.

Keratitis caused by an autoimmune disease is generally treated with corticosteroid eye drops; treatment of the underlying disease reduces the risk of recurrent keratitis.

INFECTIOUS CHERATITES

Infectious keratitis tends to progress rapidly; therefore, a timely intervention is essential to prevent any complications.

Based on the causative agent, treatment for infectious keratitis involves topical application and / or systemic administration (by mouth or intravenously) of:

• Antibiotic drugs: ex. Levofloxacin, Gatifloxacin, Ofloxacin
• Antiviral drugs: ex. acyclovir (drug of choice for the treatment of viral herpes virus keratitis)
• Antifungal drugs: ex. Voriconazole (indicated for the treatment of Candida and Fusarium keratitis)

In general, to speed up healing and reduce corneal inflammation in a short time, the doctor prescribes a cure with corticosteroid drugs to be applied directly to the eye. However, it is recommended not to undertake a do-it-yourself treatment with this type of drugs: in the context of a viral keratitis, for example, the abuse of the aforementioned topical medicaments can favor the appearance of very dangerous corneal ulcers.

deepening

Acanthamoeba-supported keratitis is the most dangerous corneal inflammation ever. When the diagnosis and therapy are not immediate, there is a risk of encountering devastating side effects, such as loss of vision in particular.

If the vision is severely impaired, the doctor may recommend a corneal transplant.

Prevention

Considering that the habit of wearing contact lenses every day is an important risk factor for keratitis, we understand how the proper use and cleaning of the lenses are essential to avoid inflammation due to traumatic corneal origin.

To prevent traumatic keratitis due to inappropriate use of contact lenses, we recommend:

• Prefer disposable contact lenses, to change from day to day
• Remove the lenses before sleeping
• Wash and dry your hands thoroughly before inserting or removing contact lenses
• Handle contact lenses carefully, avoiding scratching or damaging them
• Always use good quality products for washing and maintaining contact lenses
• Do not wear contact lenses before swimming

The best way to prevent traumatic keratitis is to wear glasses and sunglasses

Patients with dry eye syndrome should frequently use lubricating eye drops to minimize the risk of corneal injury or trauma.

For the prevention of viral keratitis (and recurrent forms), we recommend:

• Do not bring your hands to the eyes in case of viral Herpes simplex infection (eg Herpes labialis)
• Do not use cortisone eye drops without first consulting your doctor: this type of eye drops can increase the risk of keratitis and, in the case of a viral infection, even aggravate the problem
• Avoid using contact lenses in case of recurrent keratitis