Diabetes Insipidus

Khiria El-Feghi

Student at Kennedy Collegiate Institute, Windsor, Ontario, Canada

DMI Gazette, August 18, 2005

 

What is Diabetes Insipidus?

·        an atypical increase in urine production, fluid intake, and frequent thirst

·        a person with diabetes insipidus (DI) experiences an average urine output of 18 litres per day (the average urine output in a normal person is about 1.5 litres per day )

What gland is involved?

      Pituitary gland:

·        stores and secretes ADH

·        situated below the hypothalamus

     Hypothalmus:

·        produces ADH

o       ADH directs the kidneys to decrease urine production by restoring supplementary water to the bloodstream

 

What are the types of Diabetes Insipidus?

Central Diabetes Insipidus:

  • caused by impairment to the hypothalamus or the posterior pituitary gland

  • regularly after neurosurgery, infection, tumor, head injury, or a genetic disorder

  • the pituitary gland is not capable of producing adequate ADH (antidiuretic hormone)

         Treatment:

  • only the symptoms can be predominantly or entirely eradicated by various drugs including the modified form of vasopressin known as desmopressin or DDAVP

Nephrogenic Diabetes Insipidus:

  • caused by drugs such as Lithium and chronic disorders such as sickle cell disease or kidney failure
  • kidneys become unresponsive to ADH

         Treatment:

  • maybe be curable by eradicating the drug triggering the disease
  • heritable form; cannot be cured but symptoms can be somewhat relived

Dipsogenic Diabetes Insipidus:

  • caused by a defect in the hypothalamus relating to the thirst mechanism
  • excessive intake of fluids suppresses ADH

          Treatment:

  • cannot be cured presently
  • symptoms can be relived

Gestational Diabetes Insipidus:

  • develops during pregnancy
  • occurs if the pituitary gland is to some extent damaged
  • occurs if the placenta destroys the ADH too quickly
  • the placenta is a structure of blood vessels and innumerable other tissues that mature with the fetus. The placenta also allows exchange of nutrients and waste products between the fetus and the mother.
  • perishes frequently 4-6 weeks post- pregnancy

          Treatment:

  • treated with DDAVP but treatment stops 4-6 weeks post-pregnancy

 

Reference:

1. “Diabetes Insipidus,” Microsoft® Encarta Encyclopaedia 2000. © 1993-2000 Microsoft Corporation. All Rights Reserved.

2.  Robertson GL: Diagnosis of diabetes insipidus. Frontiers of Hormone Research 1985; 13: 176-189.