Sensorineural Hearing Loss in Infants with Mild Symptoms of Congenital Cytomegalovirus Infection

Abstract

We report two infants of inapparent congenital cytomegalovirus (CMV) infection accompanied by sensorineural hearing loss. In both patients, this impairment was bilateral and of significant magnitude.
Patient 1. A female infant was born at 35 weeks of gestation and weighed 1516 g at birth. She was in good condition. On admission, the serum IgM level was 31 mg/dl in the laboratory examination. Virological studies revealed significantly elevated anti-CMV IgM antibody titers and CMV was isolated from the urine. Maternal serological investigation revealed positivity for anti-CMV IgM antibody.
Patient 2. A male infant was born at 36 weeks of gestation and weighed 1800 g at birth. He was in good condition. Hepatosplenomegaly was noticed at 35 days after birth and anti-CMV IgM antibody was detected in the serum. CMV was isolated from the urine at 50 days after birth. Maternal serological investigation revealed negative anti-CMV IgM antibody. However, the serum of the mother was seropositive to anti-CMV IgG antibody at 32 weeks of gestation.
Recently, it was reported that the maternal seropositive rate of C MV antibody had decreased significantly in Japan, which may be responsible for the high incidence of congenital cytomegalovirus infection.
Therefore, we should establish a diagnostic procedure for congenital CMV infection to enable the discovery of congenital sensorineural hearing loss.