Acanthamoeba keratitis: Prevention, Diagnosis, and Treatment
Acanthamoeba keratitis is a rare but potentially serious eye infection if not detected and treated promptly. It affects the cornea, the transparent layer covering the eye, and can cause intense pain, blurred vision, and in severe cases, vision loss.
Although most cases occur in people who wear contact lenses, anyone can be affected if their eye comes into contact with contaminated water or suffers a corneal injury. In this article, with the help of Dr. Óscar Gris, a specialist from IMO Grupo Miranza, we explain in depth what Acanthamoeba keratitis is, its risk factors, symptoms, diagnostic methods, and treatment, as well as how to prevent it.
What is Acanthamoeba keratitis?
“It is an eye infection caused by a microorganism called Acanthamoeba, which is naturally present in water (tap water, swimming pools, rivers, or lakes), soil, and other surfaces. This amoeba can invade the cornea and cause inflammation that, without proper keratitis treatment, can lead to serious damage and permanent visual sequelae,” explains Dr. Gris
Causes and risk factors of Acanthamoeba keratitis
The main risk factor is the use of contact lenses without proper hygiene measures. Swimming, showering, or relaxing in hot tubs while wearing lenses also increases the risk, as does using tap water or homemade solutions to clean the lenses. Additionally, small corneal injuries or trauma can facilitate the entry of this microorganism. Exposure to contaminated water and contact with soil are other factors to consider.
Symptoms and diagnosis of Acanthamoeba keratitis
“The most striking symptom is intense eye pain. Other common signs include eye redness, foreign body sensation, constant tearing, photophobia, and blurred vision. In advanced stages, corneal ulcers may develop,” warns Dr. Gris.
In the presence of these symptoms, it is important to visit an ophthalmologist without delay to undergo the necessary tests: from a thorough examination in consultation with a slit lamp to corneal stains, cultures, and molecular biology techniques such as PCR.
Acanthamoeba keratitis can easily be mistaken for other types of infections—which are treated differently—if a thorough examination is not conducted by a specialist in corneal diseases. Given its particularly aggressive progression, obtaining a reliable diagnosis as soon as possible is the best strategy to improve prognosis and prevent complications that could lead to permanent eye damage.
Treatment of Acanthamoeba keratitis
The treatment for amebic keratitis is usually complex and prolonged, as this organism is resistant to many drugs. Depending on the case, different types of topical antimicrobials may be combined, with the specialist adjusting the prescription according to the evolution, under constant monitoring. In severe cases or those that do not respond to treatment, if the corneal tissue is severely damaged, a keratoplasty or corneal transplant may be necessary to restore vision impaired by the presence of scars or deep wounds.
How can Acanthamoeba keratitis be prevented?
Preventing this infection is possible in most cases if good habits are adopted. Eye hygiene is essential: always washing hands before handling contact lenses and ensuring they are inserted and removed in a clean environment significantly reduces the risk. It is also important not to use contact lenses for longer than the manufacturer recommends. To prevent infections, daily-use lenses are especially advisable. In the case of extended-use lenses (weekly, monthly, etc.), they should only be cleaned and stored using specifically designated products and solutions, never water.
In fact, avoiding contact between lenses and tap water, shower water, or any non-sterile water is one of the essential measures. According to Dr. Gris, “Wearing contact lenses at the beach, in the pool, or for water sports is a widespread practice that seriously compromises eye health, although many patients are unaware of it.”
Advice for patients with Acanthamoeba keratitis
For patients suffering from this infection, discipline and consistency with treatment are essential. Following the guidelines without interruptions is the foundation of a good recovery. Additionally, it is necessary to maintain strict eye hygiene, avoid using contact lenses until authorized by a specialist ophthalmologist, and remain attentive to any new symptoms or discomfort. Regular follow-up visits are crucial, and although the process can be long and sometimes frustrating, patience and adherence to medical instructions are key to minimizing damage and preserving vision. Preventing relapses and continuous care are fundamental to protecting long-term eye health.
