Objective

Thyroid hormone is necessary for normal development of the auditory system. The aim of this study was to investigate the rate of hearing impairment in congenitally hypothyroid (CH) patients, and its relation with factors such as CH severity and age at starting treatment, during CH screening program in Isfahan.

Methods

Hearing acuity was assessed in two groups of children with (94 patients aged 4 months – 3 years) and without CH (450), between 2000-2006. Otoacostic emission (OAE) was performed by a two step method. After two tests without OAE signals bilaterally, they were referred for auditory brainstem response (ABR) test. Subjects with both OAE and ABR abnormal test results were considered to have hearing problem. Obtained data was compared in case and control group and also CH patients with and without hearing impairment.

Findings

Three (3.2%) of patients and 1 of control group (0.2%) were diagnosed with sensorineural hearing loss. The rate of hearing loss was not different significantly in two studied groups (P>0.05). There was no difference between age of starting treatment and first T4 and TSH level in CH patients with and without hearing loss (P>0.05). CH neonates with hearing impairment had thyroid dyshormonogenesis according to the follow up results.

Conclusion

The rate of hearing loss was low among our studied CH patients. It may be due to proper management of CH patients. In view of the fact that all CH neonates were dyshormonogentic and considering the relation between certain gene mutations and hearing impairment in CH patients, further studies with larger sample size, with regard to different etiologies of CH should be investigated to indicate the possible gene mutations related to hearing loss in CH.

BACKGROUND:

The Hepatitis B (HB) vaccine response in hemodialysis patients is less than healthy individuals. Different strategies have been taken into account to improve the response rate. This study aimed to evaluate the effect of tetanus and diphtheria (Td) vaccine as an adjuvant therapy to HB vaccination.

METHODS:

Sixty three end-stage renal disease patients were recruited on dialysis that were older than 18 years and had passed at least 3 doses of HB vaccination schedule, and had HBS antibody (Ab) with titer less than 10 IU/L. The patients were divided into two groups; A (30 patients) and B (33 patients). Both of the groups received a 3-dose HB vaccination schedule of 40 μ g intramuscularly in the left deltoid muscle at 0, 1 and 6 months. Group A also received Td vaccine intramuscularly simultaneous with the first dose of HB vaccine. HBS Ab was measured in periods of 1 and 6 months after completion of the vaccination.

RESULTS:

One month after completion of the vaccination, group A had better but not significant response rate (96%) than group B (83.9%) (p > 0.05); in addition, after 6 month there was no difference between the two groups (87.5% vs. 83.3%) (p > 0.05). Patients with HCV infection had lower response rate than patients who did not have HCV infection (33.3% vs. 92.5%) (p < 0.05). Age had negative effect on immune response to HB vaccination (r = -0.339; p = 0.005).

CONCLUSIONS:

The use of Td vaccine concurrent with HB vaccination may increase the response rate in non-responder individuals; however, it seems it does not have any role in the persistence of immune response. Age and HCV infection negatively affected the response to HB vaccination in dialysis patients.