Symptoms and Signs Associated with Infection by Different Adenoviral Serotypes in the Eye

1. Robert Blum¹
2. Shyamanga Borooah¹
3. Roly Megaw¹
4. Ashraf Khan¹
5. Kate Templeton²
6. Bal Dhillon¹

¹Princess Alexandra Eye Pavilion, Edinburgh, Scotland
²Specialist Virology Department, Edinburgh, Scotland.

Purpose
To correlate symptoms and signs and severity of disease associated with different serotypes in adenoviral conjunctivitis. Serotyping of adenoviruses causing conjunctivitis is limited in recent times and there is a lack of understanding of the clinical impact of different adenovirus types in conjunctivitis

Methods
All patients presenting to the Princess Alexandra Eye Pavilion with symptoms and signs consistent with adenoviral conjunctivitis had viral swabs sent to the specialist Virology unit. Swabs positive for adenovirus on PCR testing were then typed by sequencing of hexon gene. Symptoms and signs were recorded in a standardized manner. Severity of disease was then correlated to adenoviral serotype.

Results
50 consecutive cases of PCR proven adenoviral conjunctivitis were included in the study. 85% of samples were successfully typed. A correlation was found between serotype and disease severity; the most severe disease was seen in serotype 8 while the mildest cases were associated with serotype 4 infection. There was also recombinant subtype, adenovirus 53 identified.

Conclusions
Adenoviral serotype is predictive of disease severity in adenoviral conjunctivitis. While most cases of adenoviral conjunctivitis resolve rapidly and completely using only supportive measures, identifying those serotypes more likely to cause severe disease may aid in the decision to commence topical steroid, antiviral therapy as well as further clinical management. Identification of adenovirus subtypes should be included in cases of adenovirus conjunctivitis to understand the impact of adenovirus conjunctivitis.