1. Nephrogenic DI (NDI) -
Mechanism: Insensitivity (Resistance) of the kidney to antidiuretic hormone (ADH).
Causes: Lithium toxicity, Hypercalcaemia, Hypokalaemia, Hypoproteinaemia, Post-obstructive Diuresis, Renal Transplantation, Amyloidosis, Multiple Myeloma, Sickle Cell Disease, Pyelonephritis, Congenital.
Other Drugs (Amiodarone, Amphotericin B, Clozapine, Colchicine, Demeclocycline, Foscarnet, Gentamicin, Loop Diuretics, Rifampicin)
2. Cranial/central/hypothalamic/neurogenic DI (CDI) –
Mechanism: Reduced or absent production of ADH.
Causes: Brain Tumour, Head Injury, Neurosurgical, Hypoxic Brain Injury, CNS Infection
3. Gestational DI – Increased placental vasopressinase production or as a variant of central or NDI developing during pregnancy.
