Role of the Adenoplus test in refractory, recurrent and clinically undiagnosed conjunctivitis

In diagnosing adenoviral conjunctivitis, polymerase chain reaction (PCR) is widely adopted as a diagnostic tool. A new antigen-based immunoassay test (AdenoPlus; Rapid Pathogen Screening Inc, Sarasota, Fla.) is commercially available as an alternative diagnostic test. To date, evidence around the role of this test in the clinical setting has been limited and contradictory.

To determine the sensitivity and specificity of the AdenoPlus test relative to PCR in detecting the presence of adenovirus in patients with conjunctivitis that is recurrent, refractory to treatment, or clinically of unknown etiology.

A prospective study of 27 patients presenting to an acute eye clinic with conjunctivitis that is recurrent (Group A), refractory to treatment (Group B), or clinically of unknown etiology (Group C). All patients underwent the AdenoPlus test and PCR analysis. Sensitivity and specificity were calculated for AdenoPlus using PCR as a reference standard.

Of 27 patients, 7% were in Group A, 19% in Group B, and 74% in Group C. Relative to PCR, the AdenoPlus test demonstrated a sensitivity of 33.3% (95% CI 4% to 78%) and specificity was 95.2% (95% CI 76% to 100%). Positive predictive value was 66.7% (95% CI 9% to 99%); negative predictive value was 83.3% (95% CI 63% to 95%).

Due to its high specificity, AdenoPlus may be a good diagnostic test, although further study is indicated. Due to its low sensitivity, however, the test should not be used as a screening tool in patients presenting with these features of conjunctivitis.