August 2019

CORNEA

Presentation Spotlight
Infectious keratitis in Russia


by Stefanie Petrou Binder, MD EyeWorld Contributing Writer


Ulcer caused by Pseudomonas aeruginosa, third day from the onset of the disease; untreated condition


Pseudomembrane in a case of adenoviral conjunctivitis, eighth day of the disease

Severe fibrosis after adenoviral conjunctivitis

Removal of pseudomembrane from the upper eyelid in case of acute adenoviral conjunctivitis
Source (all): Dmitry Maychuk, MD

 

Many different organisms can cause infectious keratitis, and it is of paramount importance for ophthalmologists to recognize the telltale signs in the cornea and follow procedure accordingly. During a keynote lecture at the 23rd European Society of Cataract and Refractive Surgeons Winter Meeting, Russian specialist Dmitry Maychuk, MD, reviewed the incidence and etiologies of infectious keratitis in Russia, discussing treatment protocols followed by Russian physicians.

Bacterial keratitis

Russian studies show the etiology of infectious keratitis as related to a number of origins. Acanthamoeba and Pseudomonas are implicated among bacterial infections of the cornea. Evidence suggests that the yearly number of cases of keratitis from Acanthamoeba is about 400 (population 146 million). The average time of development is 3 months and it is bilateral in 10% of cases. Studies have shown no association with 1-day lens use, orthokeratology, or appropriate cleaning or wearing procedure. The treatment regimen includes the instillation of lens cleaning solutions, topical use of voriconazole and fluconazole, as well as aggressive treatment with phototherapeutic keratectomy. Lens use is associated with Pseudomonas infections, which tend to develop corneal ulcers, as the causative agent is often not immediately recognized. Routinely the infections are treated with chloramphenicol and ofloxacin four times per day for 3 weeks, which is being changed by the new Russians protocols and standards.
“Acanthamoeba is not a big issue in Russia, however, the problem is that doctors don’t recognize Acanthamoeba or Pseudomonas infections, as we in the hospitals receive infected patients in different clinical stages. We are trying to push doctors away from long-term treatments and encourage them to do keratectomy in cases when they suspect Acanthamoeba,” Dr. Maychuk said.

Viral keratitis

Changes in the clinical picture of adenoviral keratoconjunctivitis occur every 3–4 years, seemingly affected by tourism in and out of Russia. Dr. Maychuk noted a large increase in infections after the 2014 Winter Olympics and more recently after the FIFA World Cup, both of which brought people from all over the world to Russia.
“Russia is a closed ecological system, and we do not travel very much. Small, minor changes in the people coming into the country affect how adenoviral keratoconjunctivitis occurs,” he explained.
According to Dr. Maychuk, a national survey that included 24 ophthalmological centers and 2,400 patients showed pseudomembranes in adenoviral keratoconjunctivitis occur in 1/30 individuals; of these about 2% lead to severe fibrosis.
“Russian ophthalmologists do not recognize pseudomembranes. Some feel challenged to remove them or think they might go away spontaneously. We included the removal of pseudomembranes in our national treatment protocol and are trying to push doctors to use surgical techniques on these pseudomembranes, especially for recurrences,” he said.
Data reveal that 1/17 patients with acute adenoviral infiltrates develop them again after a few weeks, even after treatment with cyclosporine 0.05%. Evidence suggests that PCR diagnostics do not show adenoviral DNA in conjunctival smears. A cytokine gene expression study in cultured cells of conjunctival scrapings suggests an ongoing immune inflammatory process. Therapy includes anti-inflammatory and immunosuppressive treatment for 6 months to increase the percentage of relapse-free flow.
“National survey data reveal that Russian ophthalmologists diagnose a lot of dry eye in glaucoma patients. They will often switch patients to regimens using preservative-free anti-glaucoma medications, however, they underestimate the role of allergy with anti-glaucoma agents and the fact that the allergic reaction does not subside upon ending treatment with that drug,” Dr. Maychuk said.
The study performed at Fyodorov Eye Microsurgery Institution suggests that a large majority of patients with Thygeson’s keratitis are positive for either cytomegalovirus or Epstein-Barr virus. Dr. Maychuk’s treatment protocol includes long-term, high-dosage, systemic antiviral drugs, like valacyclovir 1,500 mg/day for 3 months with topical cyclosporine 0.05%.
Diseases associated with filamentary keratitis include thyroid gland dysfunction, rheumatoid arthritis, Sjögren’s syndrome, and diabetes mellitus.
“We found that many patients with severe dry eye did not develop filamentary keratitis, and we focus on concomitant diseases in these patients,” he said.
The causes of recurrences in cases of herpetic keratitis are often misunderstood. These include: dry eye, the lack of long-term reparative topical treatments, lack of standard tree branching pattern, and patients quitting treatment with artificial tears. According to Dr. Maychuk, recurrent erosions occur in 32% of all cases after primary herpes eye infection.
“A problem in our country is to get patients to come back to the clinic with recurrences of herpetic keratitis,” he said.
Ulcerative keratitis in children results from chronic blepharitis, allergic conjunctivitis, and herpes infections. The problem in Russia is the limited access to ophthalmic care and the non-controlled use of antibiotics and antihistamines. Some data reveal that the average time between infection and an ophthalmologist visit is 19 months. Treatment protocols now include antiviral systemic treatment, topical steroids, and topical cyclosporine.
The incidence of cytomegalovirus infection in chronical recurrent keratitis was shown to be up to 83%, according to Russian investigations. Dr. Maychuk suggested that based on his data, cytomegalovirus could often be a cause of stromal keratitis.

About the doctor

Dmitry Maychuk, MD
Head of the Therapeutic
Ophthalmology Department
Fyodorov Eye Microsurgery Institution
Moscow, Russia

Financial interests

Maychuk
: None

Contact information

Maychuk: maychuk@mail.ru

About the doctor

Dmitry Maychuk, MD
Head of the Therapeutic
Ophthalmology Department
Fyodorov Eye Microsurgery Institution
Moscow, Russia

Financial interests

Maychuk: None

Infectious keratitis in Russia Infectious keratitis in Russia
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