Yohko Baba

Etiology of Severe Sensorineural Hearing Loss in Children: Independent Impact of Congenital Cytomegalovirus Infection and GJB2 Mutations

BACKGROUND Sensorineural hearing loss (SNHL) is the most common congenital disease. Longitudinal studies of infants with congenital cytomegalovirus (CMV) infection have demonstrated an association between CMV and SNHL. However, because of the lack of suitable neonatally collected specimens, the proportion of CMV-associated SNHL has not been defined, nor has the relationship between CMV and the major genetic causes of SNHL, such as mutations in the GJB2 gene. METHODS Sixty-seven children with severe SNHL were analyzed for CMV and human herpesvirus 6 (HHV-6) infections and for GJB2 mutations. DNA specimens were prepared from dried umbilical cords, which are available for everyone born in Japan. Four children with typical symptomatic infection at birth served as positive control subjects. RESULTS Congenital CMV infection and GJB2 mutations were identified in 15% and 24% of the patients, respectively. HHV-6 was not detected. All children with CMV-associated cases developed SNHL before they were 2 years old. Most children with CMV-associated SNHL had no obvious clinical abnormality at birth, and their viral loads were lower than those of symptomatic children. CONCLUSIONS Congenital CMV infection is an important cause of severe SNHL, and it has an incidence comparable to that of GJB2-associated SNHL.

Why is otosclerosis of low prevalence in Japanese

Objective This study aimed to clarify the reasons why clinical otosclerosis, a very common disease among Caucasians, is not prevalent among Japanese. Study Design The incidence, site, activity, and volume of otosclerotic foci were examined in 1011 temporal bone sections from 507 Japanese individuals. Setting This study was prepared at the temporal bone laboratory, Fukushima Medical University, Fukushima. Results Otosclerotic foci were observed in 2.56% of individuals and in 1.48% of the ears. The most common site of involvement was anterior to the oval window region, but this was only in 38.9% of the ears with otosclerotic foci. The otosclerotic foci were not involved in the stapediovestibular articulation or the endosteal layer of the otic capsule in any ears. An active change of the otosclerotic focus was seen in 33.3% of ears with otosclerosis. The volume of otosclerotic foci at the site anterior to the oval window region was less than 0.8 mm3 in 5 out of 7 ears. Conclusion The incidence of histologic otosclerosis among Japanese seemed to be almost the same as that among Caucasians. Three reasons why clinical otosclerosis was not as prevalent among Japanese as among Caucasians are suggested: low incidence of involvement of foci anterior to the oval window, low activity, and small lesion without involvement of the footplate and/or membranous labyrinth of the inner ear.

Castleman's Lymphoma in the Neck; A Case Report

We encountered a case of Castlemans lymphoma in the right side of the neck of an 18-year-old male patient. The present case involved a mixed-type lymphoma which comprises only a few percent of Castlemans lymphoma in the head and neck region in Japan. Although Castlemans lymphoma occurs most frequently in the mediastinum, it can occur in the head and neck. The usual treatment is excision and the prognosis is usually good. We must take Castlemans lymphoma into consideration when we diagnose head and neck masses.