Detection of human cytomegalovirus DNA in perilymph of patients with sensorineural hearing loss using real-time PCR

Although cytomegalovirus (CMV) has been detected in the inner ear fluid of patients who succumbed to the complications of symptomatic congenital CMV infection, it has not been detected in the inner ear fluid of living patients. In this study, real-time polymerase chain reaction (PCR) was used to measure CMV DNA in clinical samples (including perilymph) collected from five patients with deafness. In case 1, diagnosed as a symptomatic congenital CMV infection, 3 copies/μl of CMV DNA were detected in perilymph, although no viral DNA was detected in peripheral blood mononuclear cells (PBMCs) or urine samples. In case 4, a suspected asymptomatic congenital CMV infection, 36 copies/μg of CMV DNA were detected in PBMCs, but neither perilymph nor urine contained viral DNA. Likewise, in case 5, a case of deafness of unknown origin, 48 copies/μg of CMV DNA were detected in the PBMCs, but none in the perilymph or urine. CMV DNA was not detected in the samples obtained from the remaining two cases with deafness of unknown etiology. To our knowledge, this is the first report to detect CMV DNA in an inner ear sample obtained from a living human subject.