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- Fri Jun 11, 2010 10:03 pm
Up until a month ago I have never had any health issues. Then one day I woke up with an extreme thrist, then a few days later I started experiencing strong headaches. I went to the doctor and had my blood drawn. They concluded that I didn't have Diabetes. I then saw a Nephrologist and, after tests, he diagnosted my with Diabetes Insipidus. I have been taking the nasal spray treatment of DDAVP and it seemed to help with the thirst, but my headaches never went away. I also had an MRI that didn't show any brain tumors or anything abnormal with my pituitary gland. I was later seen by a Endocrinologist and he told me that he doesn't believe I have Diabetes Insipidus and gave me the pill of DDAVP to use instead of the nasal spray. He also had me get more blood drawn and saw that my blood sugar was low as well as my potassium. A week ago my muscles and joints started to ache terribly bad. What could have caused this sudden outbreak of symptoms and chronic headaches (which still affect me everyday)? Could it be the low potassium, and if so, what could cause the low levels of potassium (todays level was 3.2)?
| Dr.M.Aroon kamath
- Tue Jun 29, 2010 2:01 pm
Diabetes insipidus(DI) may be caused by
1. a defect in Anti-diuretic hormone production, or
2. a defect in the kidneys' response to ADH.
Usually the patients with Diabetes insipidus pass >3litres/24 hours of low osmolality (<300 mOsmol/kg) urine.
Defects in Anti-diuretic hormone production may arise from conditions affecting the hypothalamus/posterior pitutary (cranial or central DI).
Defect in the kidneys' response to ADH is called as Nephrogenic DI.
Causes of Diabetes insipidus may be
- Acquired or
The causes of the aquired DI are..
Tumours: germinomas, craniopharyngiomas, hypothalamic metastases, hypothalamic gliomas, lymphomas, & large pituitary tumours with suprasellar involvement.
Trauma: Head injury, Intracranial surgery.
Granulomata: tuberculosis, sarcoidosis, Wegener's,& histiocytosis.
Infections: meningitis, encephalitis, brain abscess
Vascular disorders: Sheehan's syndrome (post-partum pituitary necrosis),aneurysms, haemorrhage/thrombosis & sickle-cell disease.
Radiotherapy induced damage.
Inherited disorders: Autosomal recessive [ex; a combination of diabetes insipidus, diabetes mellitus, optic atrophy, deafness (DIDMOAD) - Wolfram syndrome] &
Autosomal dominant(Mutations of vasopressin gene).
Causes of Nephrogenic diabetes insipidus: chronic renal insufficiency, hypercalcemia, hypokalemia, lithium toxicity, and tubulo-interstitial disease & rarely, diabetes mellitus.
- Osmotic diuresis (Diuretic abuse, Diabetes mellitus, hypercalcemia, Hypokalemia, and high-output renal failure) and
- Psychogenic polydipsia (PP).
You have indicated that your MRI was normal. In this situation, one needs to consider the following possibilities.
- chronically low potassium levels leading to a DI-like state,
- conditions that sometimes may not show up readily on MRIs of the brain, such as Histiocytosis, &
- the rare inherited causes of DI.
Langerhans cell hisitocytosis (adult onset) deserves special mention in this context.
Not all patients with Langerhans cell hisitocytosis develop Diabetes Insipidus. Estimates vary from 5% to 50%, with an average of 30% of cases. Whole body MRI used for diagnosis(bony lesions). Presentation can be a single site or multi site involvement. Single site involvement of the posterior pitutary is known to occur.Multi site presentations are generally easier to diagnose.
I hope this information is useful to try and understand the difficulties in arriving at a specific etiology of Diabetes Insipidus in some cases.Please continue to be in touch with your endocrinologist who will be able to guide you better.