Epidemic keratoconjunctivitis: A review of current concepts in management

Abstract

Epidemic keratoconjunctivitis (EKC) is an ocular surface infection caused by adenovirus. To date, there are no approved topical antiadenoviral therapeutics to treat EKC. Recent research reveals that treatment with topical corticosteroids for symptomatic relief of EKC enhances adenovirus replication and delays cell shedding from the ocular surface which delays adenovirus elimination. The current management of EKC largely revolves around accurate diagnosis of the condition and implementation of disinfection protocol to prevent its spread. Development of an effective antiviral treatment that addresses inflammation and does not prolong viral shedding would provide significant benefit. The literature reports on a variety of therapeutics that could potentially satisfy this deficiency. Topical ganciclovir and povidoneiodine combination drops have shown the most recent potential, but both therapeutics need to be investigated in larger scale studies. Until an antiadenoviral option is produced, the treatment of EKC should maintain a judicious case by case approach aiming to contain its dissemination and prevent visual consequences. Queratoconjuntivitis epidémica: revisión de los conceptos actuales de tratamientoResumen La queratoconjuntivitis epidémica (QCE) consiste en una infección de la superficie ocular causada por adenovirus. Hasta la fecha no existen terapias antiadenovíricas aprobadas para tratar la QCE. Las investigaciones recientes revelan que el tratamiento con corticoesteroides tópicos para un alivio sintomático de la QCE aumenta la replicación del adenovirus y retrasa la descamación de células en la superficie ocular, retardando la eliminación del virus. El tratamiento actual de la QCE gira alrededor del diagnóstico preciso sobre la condición clínica y la introducción de un protocolo de desinfección que impida su diseminación. El desarrollo de un tratamiento antivírico eficaz que trate la inflamación y no retrase la eliminación vírica supondría un beneficio considerable. La literatura reporta gran variedad de terapias que podrían satisfacer potencialmente esta deficiencia. La aplicación de gotas tópi-cas con una combinación de ganciclovir y iodina-povidona ha demostrado recientemente su potencial, aunque ambas terapias precisan investigarse mediante estudios a gran escala. Hasta A.M. Pihos que aparezca una opción antiadenovírica el tratamiento de la QCE debería realizarse utilizando un enfoque caso a caso, a fin de contener su diseminación y prevenir consecuencias visuales.

An Outbreak of Epidemic Keratoconjunctivitis Caused by Human Adenovirus Type 8 in Primary School, Southwest China

“…The clinical manifestations, frequency of symptoms and signs of EKC and course of the disease were different from those in other studies because of variations in the virulence, sample sizes, observation time points and influence of the observer [25, 32-34, 36, 37, 39]. The patients in our study had some common manifestations of viral conjunctivitis, as well as the common characteristics of EKC, including follicular hyperplasia, pseudomembrane formation, preauricular lymphadenopathy, corneal involvement and blurred vision [14,[39][40][41]. Conjunctival hyperaemia and increased secretion are common features of acute conjunctivitis, while watery secretions are more characteristic of viral conjunctivitis [4].…”

Adenoviruses

“…Adenoviral keratoconjunctivitis, which is a major cause of ocular morbidity, is most commonly caused by representatives of species D, including types 8, 19, and 37, but also by human adenoviruses -E4, -C5, -B3, -B7, -B11, and -B14 (Lynch et al, 2011). Gastrointestinal manifestations are mainly associated with HAdV-F40 and -F41, but HAdV-G52 and different members of species D, including some of the most recently identified types (types 65 and 67), have also been observed (Matsushima et al, 2012;2013). Respiratory tract involvement has been associated mainly with human adenoviruses -B3, -B7, -B16, -B21, and -E4 and various members of species C (Metzgar et al, 2010).…”

“…Pneumonia can last anywhere from 2 to 4 weeks and pinkeye can persist for another several days to a week. More severe keratoconjunctivitis can last for several weeks (Pihos, 2013)and entericadenoviruses can cause diarrhea that lasts up to 2 weeks which is longer than other viral diarrhea episodes (Uhnoo et al, 1984).…”

Inhibitory Effect of Abitylguanide on Adenovirus Replication

“…One of the most characteristic and severe (in its course) adenovirus infections is the epidemic keratoconjunctivitis (EKC), caused mainly by HAdV types 8,19, and 37 [4][5][6][7][8].…”

“…Promising results have also been noted with povidone-iodine (PVP-I), a microbicidal agent that also possesses virucidal properties [12]. Topical ganciclovir and PVP-I combination drops have shown the most recent potential, but both therapeutics need to be investigated in larger scale studies [8]. Cidofovir also manifested an effect against HAdV 5 infection both in vitro and in another in vivo ocular model, the New Zealand rabbit [13].…”