Frequency of Herpes Simplex Virus Types 1 and 2 and Cytomegalovirus in Perilymph and Peripheral Blood Samples of Cochlear-Implanted Children Using the Polymerase Chain Reaction Method

Background and Aim: Inner ear infection with some viruses may be one of the possible causes of Sensorineural Hearing Loss (SNHL). This study aims to determine the frequency of Herpes Simplex Virus 1 and 2 (HSV-1, HSV-2) and Cytomegalovirus (CMV) in perilymph and peripheral blood samples of cochlear-implanted children. Methods: In this cross-sectional study, 30 children with severe-to-profound SNHL (aged 1.1–5 years) underwent cochlear implantation surgery. During surgery, their perilymph  and peripheral blood samples were collected. The samples were analyzed separately for the presence of herpes HSV-1, HSV-2, and CMV by real-time Polymerase Chain Reaction (PCR) method. The load of IgG and IgM antibodies against these viruses was determined using the Enzyme-Linked Immunosorbent Assay (ELISA) method. Results: The frequency of CMV in perilymph samples was 16.7% (5 patients) and in peripheral blood samples was 3.3% (1 patient). The IgG antibody against CMV and HSV- 1 was positive in 80% and 46.7% of the patients, respectively. The IgM antibody against CMV was positive in 10%. The mean IgM serum antibody load against HSV-1, HSV-2, and CMV was 2.70, 1.70, and 5.47, respectively, and the mean IgG antibody load against these viruses was 56.07, 2.50, and 23.67, respectively. Conclusion: The IgG test is positive in cochlear-implanted children with CMV in their perilymph samples, and the CMV genome is not present in their peripheral blood. This may indicate the previous presence of this virus in the ear and its role in hearing loss.   Keywords: Sensorineural hearing loss; perilymph fluid; cytomegalovirus; herpes simplex