Pathophysiology

===Diabetes Insipidus is caused by a decreased amount of antidiuretic hormone (ADH). The two main symptoms of this are polydipsia and polyuria. Because there are small amounts of ADH released, the body is not able to retain any fluid, and therefore excretes large amounts of urine. This leads to dehydration, which causes excessive thirst (polydipsia). There are three major types of diabetes insipidus: neurogenic/central form, nephrogenic form, and psychogenic form.=== ===1. Neurogenic/central form- No ADH is released, made, or transported due to any of the following: brain tumors, surgical removal of the pituitary gland, aneurysms, thrombosis, infections, or immunologic disorders (Huether, S., & McCance, K., 2008).=== ===2. Nephrogenic form- ADH is not recognized by the kidneys. This is often cause by diseases that cause irreparable kidney damage, such as pyelonephritis, polycystic disease, or destructive uropathies (Huether, S., & McCance, K., 2008).=== ===3. Psychogenic form- Small amounts of ADH are present, but not enough for the body to function as normal. This is caused by an excessive intake of fluids on a regular basis, which causes the renal medullary concentration gradient to malfunction and causes the body to become immune to the effects of ADH (Huether, S., & McCance, K., 2008).===