March 2008

 

OPHTHALMOLOGY NEWS

 

Chronic pediatric BKC


by Maxine Lipner Senior EyeWorld Contributing Editor

 

 

New study urges more stringent treatment for chronic BKC

Children with chronic blepharokeratoconjunctivitis (BKC) face significant visual loss with delays in treatment often resulting in a decrease of best-corrected visual acuity, results from a new study suggest. The retrospective case series published in the December 2007 issue of Ophthalmology looked at the effect of BKC on 27 children with the condition, according to Joel M. Weinstein, M.D., associate professor of ophthalmology and pediatrics, Penn State University and Milton S. Hershey Medical Center, Hershey, Pa.

The condition usually starts benignly enough. “It usually manifests with light sensitivity, red eyes, and rubbing,” Dr. Weinstein said. “Unfortunately, it’s not treated vigorously enough in more cases.”

Controlling BKC

Often he finds practitioners treat the condition using just some topical antibiotics or a topical antibiotic and steroid. “What is often really needed is a prolonged course of oral antibiotics,” he said. “We usually use erythromycin in children and that seems to cover the major pathogens around the lid, along with some topical antibiotic steroid combination.” In the United States, typically this calls for a combination of either tobramycin and prednisolone or tobramycin plus dexamethasone.

While this doesn’t rid the child of BKC, it does control the condition. “This problem tends to persist for a minimum of six months, but may be active for as long as two to three years,” Dr. Weinstein said. The root of the problem is likely linked to abnormal meibomian gland secretions. These lead to bacterial overgrowth with bacterial toxins which produce an immune response on the surface of the cornea and conjunctiva, he believes. “We don’t really cure it,” he said. “However, we can control it, and then it eventually goes away by itself.”

The difficulty can be controlling the condition well enough in children to prevent vision loss, to which children can be predisposed. There are two factors at work here, Dr. Weinstein points out. “Number one, it’s much more frequent in children than in adults to have central corneal involvement,” he said. “Central corneal involvement causes visual loss both by virtue of the central opacity itself as well as by causing secondary amblyopia.” In adults BKC usually results in peripheral corneal ulcers; about 40% of children have central corneal involvement.

“The second important factor in children is induced refractive errors,” Dr. Weinstein said. “Many of these children develop astigmatism. Even without central corneal involvement, their peripheral involvement leads to some deformation of the cornea.” This difference in refraction between the two eyes can lead to amblyopia.

Case series

At Great Ormond Street Hospital for Children, a London referral center, investigators found that they were seeing a large number of these BKC cases. “Despite several well-written reports in the literature, the word really hadn’t filtered out to the general ophthalmologist that this can be a significant cause of visual loss in children,” Dr. Weinstein said. “We felt that we really needed to disseminate this information more widely.”

In this retrospective case series of 27 children ranging in age from 7 months to 15.9 years, investigators found that corneal involvement occurred in 81% of eyes. In addition, 67% of eyes had a history of recurrent chalazia. In 52% of patients, photophobia was also present. Patients were treated using a combination of modified lid hygiene, topical antibiotics, and steroids. Systemically they were put on oral antibiotics, and beginning in 2003, some were given flaxseed oil as an alternative to long-term oral antibiotics as part of their tapering regimen.

Investigators found that with treatment, patients’ best-corrected visual acuity improved in 70% of affected eyes and remained unchanged in 30%. In addition to such changes in visual acuity, 48% of patients had to be treated for amblyopia. Investigators determined that in cases where there was a two-year lag between symptom onset and treatment, there was, on average, a reduction of 0.06 logMAR units of visual acuity. Those who fared the worst visually showed bilateral corneal involvement at the start. “The results showed that the blepharokeratoconjunctivitis and the non-visual symptoms of light sensitivity and discomfort can be adequately controlled, vision can be stabilized and, in some cases, improved with vigorous treatment,” Dr. Weinstein said. “We also found that treatment needs to be prolonged. None of these children was treated for less than six months.”

One particularly intriguing result was the finding that flaxseed oil could be helpful in controlling the inflammation, Dr. Weinstein believes. This is thought to possibly affect the polar lipid profiles of the meibomium gland secretions. “That requires a little more intensive study by some people with biochemical expertise who can try to characterize differences in composition and in bacterial flora in the meibomium secretions of kids who are predisposed to BKC,” he said.

He sees the study as having three important messages. “Number one, recognize this early,” Dr. Weinstein said. “Number two, prolonged treatment is necessary. Doctors can’t send these kids home with a prescription for some antibiotic drops and tell them to come back if it bothers them.” It is important to see the children relatively frequently to be sure that the condition is controlled because the medication must be individually tailored. “The third take-home message is to be mindful of the presence of amblyopia, either with or without, you should live it up at the corneal opacification,” he said. “Amblyopia can result either from astigmatism that’s uncorrected or from opacification. Both result in prolonged suppression of the cerebral input from the affected eye.” He recommends watching for this by doing a thorough refraction and if vision is compromised, treating the refractive error and using appropriate amblyopia therapy as necessary.

Overall, Dr. Weinstein recommends treating children with BKC with erythromycin with a topical antibiotic and a topical steroid. He also urges practitioners to consider flaxseed oil as a dietary supplement after the oral antibiotic is discontinued. In the future, he hopes better treatment will be available. “I think the wave of the future is going to be unraveling the immunologic process that mediates this and using some specific immune mediators to interrupt the process,” he said.

Editors’ note: Dr. Weinstein has no financial interests related to his comments.

Contact Information

Weinstein: jweinstein@hmc.psu.edu

Chronic pediatric BKC Chronic pediatric BKC
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