Meniere's Disease in Congenital Nephrogenic Diabetes Insipidus: Report of Two Twins
| Title: | Meniere's Disease in Congenital Nephrogenic Diabetes Insipidus: Report of Two Twins |
|---|---|
| Authors: | Comacchio, Francesco; Boggian, Orazio; Poletto, Elisabetta; Beghi, Andrea; Martini, Alessandro; Rampazzo, Annalisa |
| Publisher: | American Journal of Otology |
| Date Published: | September 01, 1992 |
| Reference Number: | 300 |
Two cases, twins, affected by congenital nephrogenic diabetes insipidus (CNDI) with a high daily volume of dilute urine excretion and periods of compensatory high levels of antidiuretic hormone (ADH) simultaneously developed a fluctuating Meniere-type hearing loss. It is well known that the kidney and the cochlea are linked by structural and anatomic characteristics, as well as by the physiologic mechanism of electrolytes and fluid regulation. The patients herein described seem to be paradoxical, because they suffered from hydropic hearing loss despite the pathophysiologic mechanism of CNDI and the possible role played by ADH in water regulation in the inner ear. The consequences on Meniere's disease of the different therapeutic regimens followed by the two CNDI patients are discussed. To our knowledge these are the first cases of CNDI with Meniere's disease described in the literature.
This translation by the NDI Foundation is to assist the lay reader. To provide a clear, accessible interpretation of the original article, we eliminated or simplified some technical detail and complicated scientific language. We concentrated our translation on those aspects of the article dealing directly with NDI. The NDI Foundation thanks the researchers for their work toward understanding and more effectively treating this disorder.
© Copyright NDI Foundation 2007 (JC)
One of the twins began therapy to control his NDI: tolmetin ep b.i.d. and hydrochlorothiazide plus amiloride cp twice a week. This reduced his amount of urine voided by about half. The other twin refused a treatment plan.
Both twins assented to treatment for their Meniere's disease. The treatment proved beneficial, though temporary, for both twins. The twin who refused NDI therapy also did not participate in extensive pharmacologic treatment for his hearing disease, whereas his brother did.
The authors speculated as to whether their clients' Meniere's disease was attributable to their previous NDI condition, or disturbances of the water and hormonal control mechanisms of the ear, or whether the disease was inherited. Meniere's disease involves a disturbance of the control of both salt and water balance. And attacks of the disease (its symptoms seem to come and go) occur when the level of aldosterone secretion is low and the level of vasopressin (VP) activity is high.
The hormone, VP, is involved in regulating body water, and its signal to the kidney to do so is ignored in NDI. VP also has a direct influence on inner ear metabolism. Also, VP receptors are present in the inner ear. So perhaps VP is a link between the two diseases. However, it is not clear whether VP is associated with the mechanisms of sound transmission in the inner ear or with the regulation of fluid in the inner ear.
The VP receptor that VP binds with to regulate body water in the kidney is the vasopressin-2 receptor (V2R). At present, no one knows which VP receptor, V2R or V1R, is in the ear, or what the location and distribution of either of the VP receptors may be in the ear. It is possible that V2R and V1R are both present in the ear. Also, the fact that the twin whose NDI symptoms were modulated through treatment experienced an actual worsening of his Meniere's disease (as did his brother) suggests that VP does not have a specific role in the development of Meniere's disease. Also, since NDI is generally inherited as an X-linked trait, and Meniere's Disease shows an autosomal dominant pattern of inheritance, it may be that the two diseases are inherited independently.