Nephrogenic Diabetes Insipidus	

Acquired nephrogenic diabetes insipidus is probably the most common cause of polyuria, particularly in association with the osmotic  diuresis of diabetes mellitus. The hereditary, sex-linked form of nephrogenic diabetes insipidus is extremely rare. In all instances, there is resistance to the renal action of vasopressin and, consequently, plasma vasopressin is inappropriately high with respect to urine osmolality. 
Renal infection, post obstructive uropathy, vascular lesions, electrolyte disturbances (hypokalaemia and hypercalcaemia), amyloid, and sickle-cell anaemia are among the most common causes of nephrogenic diabetes insipidus.