Abstract: | Nephrogenic diabetes insipidus associated with high basal levels of plasma arginine vasopressin developed in a patient during lithium therapy. Fluid deprivation was accompanied by an increase in the concentration in peripheral venous plasma of vasopressin and angiotensin II, a rise in plasma osmolality and a modest rise in urine osmolality. Infusion of arginine vasopressin produced comparable levels of plasma vasopressin to those found during fluid deprivation, with no overall change in plasma angiotensin II and little change in urine volume or osmolality. It is suggested that angiotensin II may be responsible for the difference in ability to concentrate urine under these two conditions. Following death by self-poisoning, renal histology revealed distinct structural changes in the distal tubules: such lesions have not previously been described in man and it is suggested that the occurrence of nephrogenic diabetes insipidus while on lithium therapy may be related to tubular damage. |