Deficiency of ADH (vasopressin) leading to failure of urinary concentration with fluid deprivation.
Clinical features:
polyuria (>4 l/day, specific weight <1005); always nocturia compensatory polydipsia astenuria
Fluid deprivation - hypertonic dehydratadion
Differential diagnosis:
Diabetes mellitus Nephrogenic diabetes insipidus „Psychogenic” polidipsia