genitourinary disorders
Nephrogenic Diabetes Insipidus
Etiology of NDI
NDI can be Inherited Acquired The most common inherited NDI is an X-linked trait with variable penetrance in heterozygous females that affects theargininevasopressin(AVP) receptor 2 gene. Heterozygous females may have no symptoms or a variable degree of polyuria and polydipsia, or they may be as severely affected as males. In rare cases, NDI is caused by an autosomal recessive or autosomal dominant mutation that affects the aquaporin-2 gene and can affect both males and females. Acquired NDI can occur when disorders (many of which are Overview of Tubulointerstitial Diseases ) or drugs disrupt the medulla or distal nephrons and impair urine concentrating ability, making the kidneys appear insensitive to Autosomal Dominant Polycystic Kidney Disease (ADPKD) None Nephronophthisis and Autosomal Dominant Tubulointerstitial Kidney Disease (ADTKD) and medullary cystic kidney disease complex Sickle cell nephropathy Release of obstructing periureteral fibrosis Medullary Sponge Kidney None Chronic Pyelonephritis None Hypercalcemia None Amyloidosis None Sjögren Syndrome None Bardet-Biedl syndrome Certain cancers (eg, Myeloma-Related Kidney Disease , sarcoma) Many drugs, especiallylithium, but also others (eg,demeclocycline,amphotericin B,dexamethasone,dopamine,ifosfamide,ofloxacin,orlistat) Possibly chronic hypokalemic nephropathy Acquired NDI can also be idiopathic. A mild form of acquired NDI can occur in any patient who is older or sick or who has acute or chronic renal insufficiency. In addition, certain clinical syndromes can resemble NDI: The placenta can secrete vasopressinase during the 2nd half of pregnancy (a syndrome called gestational diabetes insipidus). After pituitary surgery, some patients secrete an ineffective ADH precursor rather thanvasopressin. 