Bartter syndrome overview: Difference between revisions
TayyabaAli (talk | contribs) |
TayyabaAli (talk | contribs) |
||
| Line 9: | Line 9: | ||
==Classification== | ==Classification== | ||
[[Bartter syndrome|Bartter Syndrome]] can be classified into five different types based on [[genotype]]. [[Bartter syndrome]] can result from [[homozygous]] or [[Heterozygous|mixed heterozygous]] [[Mutation|mutations]] in any of the genes. Thus, affecting the function of genes responsible for synthesis or membrane insertion of the transporters in the [[Loop of Henle|ascending limb of the loop of Henle]]. | |||
*[[Bartter syndrome]] type 1: Mutation in NKCC2 gene results in impairment of [[Na-K-2Cl symporter|sodium-potassium-chloride. cotransporter (Na-K-2Cl)]] in the [[apical membrane]]. | |||
*[[Bartter syndrome]] type 2: Mutation in [[ROMK|ROMK gene]] results in defective functioning of the luminal [[potassium channel]]. | |||
*[[Bartter syndrome]] type 3: Mutation in the ClC-Kb gene results in the impairment of the [[Chloride channel|basolateral chloride channel]]. | |||
*[[Bartter syndrome]] type 4: Defects that reduce the activity of both ClC-Ka and ClC-Kb cause [[Bartter syndrome]] associated with [[Sensorineural hearing loss|sensorineural deafness]] (types IV and IVb). | |||
*[[Bartter syndrome]] type 5: It results from a [[Mutation|gain-of-function mutation]] in the [[Receptor|Ca-sensing receptor (CaSR)]]. A [[Mutation|gain-of-function mutation]] in CaSR in the [[basolateral membrane]] of the [[Thick ascending limb of loop of Henle|thick ascending limb]] enhances the function of this receptor. This results in [[hypocalcemia]] and impairs [[Sodium chloride|sodium chloride transport]]. | |||
[[Bartter syndrome]] types 1, 2, and 4 present at a younger age. They present with symptoms, often quite severe in the neonatal period. [[Bartter syndrome]] type 3 also called classic [[Bartter syndrome]] present later in life and maybe sporadically asymptomatic or mildly symptomatic. | |||
==Pathophysiology== | ==Pathophysiology== | ||
Revision as of 11:10, 7 August 2020
|
Bartter syndrome Microchapters |
|
Diagnosis |
|---|
|
Treatment |
|
Case Studies |
|
Bartter syndrome overview On the Web |
|
American Roentgen Ray Society Images of Bartter syndrome overview |
|
Risk calculators and risk factors for Bartter syndrome overview |
Main article:Bartter syndrome
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]Associate Editor(s)-in-Chief: Tayyaba Ali, M.D.[2]
Overview
Historical Perspective
Bartter syndrome was first discovered by Bartter et al.and introduced in a seminal paper in the December issue of the American Journal of Medicine in 1962. Authors in the paper reported two pediatric patients with growth and developmental delay associated with hypokalemic alkalosis and normal blood pressure despite high aldosterone production. The syndrome named after Bartter. This disease was observed in children as well as in adults, females as well as males.Authors described in the paper that this disease is characterized by hypokalemia, metabolic alkalosis, hyperreninemia, secondary hyperaldosteronism, and normal blood pressure.
Classification
Bartter Syndrome can be classified into five different types based on genotype. Bartter syndrome can result from homozygous or mixed heterozygous mutations in any of the genes. Thus, affecting the function of genes responsible for synthesis or membrane insertion of the transporters in the ascending limb of the loop of Henle.
- Bartter syndrome type 1: Mutation in NKCC2 gene results in impairment of sodium-potassium-chloride. cotransporter (Na-K-2Cl) in the apical membrane.
- Bartter syndrome type 2: Mutation in ROMK gene results in defective functioning of the luminal potassium channel.
- Bartter syndrome type 3: Mutation in the ClC-Kb gene results in the impairment of the basolateral chloride channel.
- Bartter syndrome type 4: Defects that reduce the activity of both ClC-Ka and ClC-Kb cause Bartter syndrome associated with sensorineural deafness (types IV and IVb).
- Bartter syndrome type 5: It results from a gain-of-function mutation in the Ca-sensing receptor (CaSR). A gain-of-function mutation in CaSR in the basolateral membrane of the thick ascending limb enhances the function of this receptor. This results in hypocalcemia and impairs sodium chloride transport.
Bartter syndrome types 1, 2, and 4 present at a younger age. They present with symptoms, often quite severe in the neonatal period. Bartter syndrome type 3 also called classic Bartter syndrome present later in life and maybe sporadically asymptomatic or mildly symptomatic.