Renowned regional eye experts discussed a mysterious mass, an off-label use for tacrolimus, and characteristics of hereditary corneal dystrophy during a riveting session on cornea at the 5th meeting of the ASEAN Ophthalmology Society (AOS) on Saturday, March 26, 2022.
On Off-label Usage
Tacrolimus is a safe and effective treatment for vernal keratoconjunctivitis (VKC) and may be used as a substitute for steroid treatments to control disease activity, said Dr. Varintorn Chuckpaiwong, director of the cornea and refractive surgery service, Department of Ophthalmology, Ramathibodi Hospital, Mahidol University, Thailand.
She shared her experience about the off-label usage of tacrolimus skin ointment to treat the atopic condition of the external ocular surface. “A total of 70% of cases have a good response, longer symptom-free periods, less signs of inflammation and less steroid dependence,” she said.
Some 90% of cases can be well-tolerated to the mild side effect of stinging, which is more severe in adults than in young children. None showed severe ocular toxicity or systemic side effects.
“The application of 0.03% tacrolimus skin ointment is effective in the treatment of VKC when topical ocular preparation is not available,” she said. However, combined treatment with other VKC medications such as antihistamine, mast cell stabilizer, cyclosporine and pulse topical steroid are still needed for additional control in most of the cases, she noted.
All patients were informed about the possibility of other treatment options. The characteristics of VKC include chronic allergic conjunctivitis, most often seen in young males with onset before 10-years-of-age and lasts 2-10 years. It is recurring, bilateral and self-limiting inflammation of conjunctiva and cornea.
It is typically seasonal but year-round symptoms can be seen, especially in tropical regions. Specific activity may aggravate symptoms, such as outdoor sports and a dusty environment.
VKC is seen more often in patients with a family history of atopy. It can cause superficial punctate keratitis, corneal erosion and plaque. Corneal damage is unusual but can result in vision loss.
Non-pharmacological treatment involves identification and avoidance of allergens, stopping eye rubbing, hand washing, and ensuring one’s room is clean. Causative agents must be removed. Normal saline irrigation may be used, along with protective eyeglasses, cold compress and air conditioning.
Pharmacological treatments include artificial tears, antihistamines, vasoconstrictors, mast cell stabilizers, steroids, NSAIDs and immunomodulators. Associated conditions are treated such as dry eye, blepharitis, keratopathy and atopy.
The use of immunomodulators like cyclosporine A (CsA) and tacrolimus reduce conjunctival inflammation, steroid sparing. There is less anti-inflammatory effect than steroids. There is also a slow onset, therefore it requires long-term usage. There are also side effects including stinging, burning and blurred vision.
When TB Bacteria Attacks the Eye
Dr. Wiwan Sasanayudh, from Phramongkutklao Hospital, spoke about The Mysterious Mass. A 45-year-old Thai female office worker presented with a left conjunctival mass. Her chief complaint was an enlargement of the left eye mass for two weeks. “She had eye irritation for one month and had gone to a private eye clinic. She was treated with topical steroids and 1% pred forte and oral ibuprofen. Unfortunately, there was no improvement after the treatment,” said Dr. Sasanayudh.
Two weeks prior to visiting a hospital, she had noticed a progressive enlargement of the mass in her left eye. She had mild irritation, no pain or discharge and had normal vision. She had no underlying disease, no history of ocular trauma or ocular surgery, and no history of contact with tuberculosis.
In the left eye, there was a conjunctival mass. The mass was non-moveable, and there were no feeding vessels seen. The initial diagnosis was subconjunctival mass, which included infection, inflammation, neoplasm and nodular scleritis. A routine investigation was carried out, a complete blood count was within normal limits. An HIV test was also negative and there was no evidence of pulmonary tuberculosis.
“We did a conjunctival biopsy and sample pathology for cytometry, culture for mycobacterium, bacteria and fungus,” she said. The culture for mycobacterium tuberculosis was positive. Conjunctival tuberculosis is an infectious disease caused by mycobacterium tuberculosis. It is rare in non-endemic areas and is usually seen in healthy individuals.
The association with pulmonary tuberculosis is rare, and in this case, the chest X-ray was normal. It is generally accompanied by regional lymphadenopathy. Doctors should do a conjunctival biopsy to identify the organism. The patient was treated with tubercular drugs and showed improvement of symptoms and signs. After six months, there was complete resolution with no recurrence found.
Hereditary Corneal Dystrophy in Vietnam
Dr. Le Xuan Cung, from the National Institute of Ophthalmology, Vietnam, talked about the clinical and subclinical characteristics of hereditary corneal dystrophy in Vietnam. Dystrophies have typically referred to a group of inherited disorders that are usually bilateral, systemic, slowly progressive, and not related to environmental and systemic factors. The majority of corneal dystrophies are inherited dominantly and manifest in the first or second decade of life.
More than 20 corneal dystrophies have been found and these are categorized into four groups. In a retrospective study, data from the medical records of 109 patients with corneal dystrophy were recorded. “The study’s findings revealed that the majority of patients were diagnosed late,” he said. Some patients were not properly diagnosed during previous visits with doctors who were not cornea specialists. The study found only one person with Reis-Buckler corneal dystrophy. The patient had confluent geographic-like opacities in the Bowman’s layer and superficial stroma, and recurrent corneal erosions.
Granular corneal dystrophy type I was revealed in one patient, while granular corneal dystrophy type II was observed in 24 patients from seven families. Lesions were superficial white granules with clear delineations, and deeper branching refractile lines mainly located in the anterior and middle stroma. Lattice corneal dystrophy was discovered in 23 patients, with 19 eyes experiencing thin branching refractile lines in the anterior stroma, and 7 eyes with deep stroma and periphery. Thirteen eyes had stromal haze.
One patient had lattice corneal dystrophy Type IIIb, and was asymptomatic. Macular corneal dystrophy was discovered in 22 patients from 16 families. There was diffuse corneal opacity, and poorly delineated fleck-like opacities in stroma. Seven eyes had severe corneal opacity.
Twenty-three patients had Fuchs’ endothelial corneal dystrophy, with 25 of the eyes having clear cornea with cornea guttata. Congenital hereditary endothelial dystrophy was found in three patients. They had corneal clouding and thickening, and nystagmus.
Editor’s Note: The 5th AOS Congress was held virtually on March 26-27, 2022. Reporting for this story took place during the event.
