A clinico-virological study on identification of viral aetiological agents in conjunctivitis

Abstract

Purpose: To identify and isolate various viral aetiological agents that cause conjunctivitis among patients with suspected viral conjunctivitis or keratoconjunctivitis who attended the outpatient department (OPD) at a tertiary eye care hospital in Chennai during June 2018 to October 2019 and to correlate the clinical symptomatology with the respective isolated virus. Methods: The study population consisted of 75 patients (age ranging from 6 to 82 years; mean age: 37.3 years) with conjunctivitis of suspected viral aetiology. Samples were obtained using a swab from the inferior palpebral conjunctiva of the affected individual using Dacron swabs placed immediately in a viral transport medium (VTM) and transported to a tertiary virology lab in Chennai, Tamil Nadu in cold chain for screening. All of the above samples were subjected to virus isolation using virus-susceptible cell lines as well as by molecular diagnosis of viruses such as herpes simplex virus, adenovirus, and enterovirus by real-time polymerase chain reaction (PCR). Results: Among the samples obtained, viral aetiology was identified in 58.67% of conjunctivitis samples either by PCR or virus isolation. Among the virus-positive samples, adenovirus, enterovirus, and herpes simplex virus accounted for 40.91%, 31.81%, and 27.27%, respectively. Coexistence of viruses was observed in 18.18% of virus-positive patients. Conclusion: This study identifies adenovirus as the most common viral pathogen that caused conjunctivitis among the study patients followed by enterovirus and herpes simplex virus. More than one viral pathogen was identified in some of the conjunctivitis patients and this showed that the conjunctivitis in the study group was caused by coexistence of various viruses.