Determination of Prevalence, Sensitivity and Specificity of Clinical Signs and Symptoms of Adenoviral Keratoconjunctivitis

Abstract

Background: Adenoviral keratoconjunctivitis is a prevalent form of eye infection which involves the conjunctiva and less commonly the cornea. The signs and symptoms of the disease are more often overlapped with other causes of conjunctivitis. In this study, we applied polymerase chain reaction (PCR) as a sensitive test for diagnosis of adenovirus to determine the prevalence, sensitivity, and specificity of each sign and symptom of adenoviral keratoconjunctivitis. Methods: This descriptive, analytic, cross-sectional study was conducted from September 2011 to September 2012 at Feiz Hospital of Ophthalmology and laboratory of virology, affiliated to Isfahan University of Medical Sciences, Iran. After obtaining ocular specimens from 195 patients with general signs and symptoms of conjunctivitis, their signs and symptoms were recorded. The specimens were tested by PCR to evaluate adenoviral etiology. Prevalence, sensitivity, and specificity of each sign or symptom was measured based on the findings of PCR. Findings: The ocular specimens were collected from 106 (55%) males and 87(45%) females with the mean age of 27.3 ± 7.1 years old. The prevalence of adenoviral keratoconjunctivitis was 11.4 %. There was no significant difference in signs and symptoms between patients with positive and negative adenoviral PCR test. The most sensitive (100%) sign and symptom were conjunctival hyperemia and sudden onset, respectively. The least sensitive (0%) sign and symptom were blepharospasm and membrane/pseudomembrane formation, respectively. The most specific (98.84%) and the least specific (1.16%) were blepharospasm and conjunctival hyperemia, respectively. Conclusion: Although many signs and symptoms accounted for adenoviral conjunctivitis, there was no hallmark for disease diagnosis. Conjunctival hyperemia is a sensitive criterion to diagnose adenoviral keratoconjunctivitis and there was no prevalent specific criterion for this purpose. Keywords: Keratoconjunctivitis, Adenovirus, Sensitivity and specificity, Polymerase chain reaction