Bartter's syndrome

Bartter's syndrome is AR inherited tubulopathy with a combination of disorders of water and electrolyte metabolism.

The syndrome arises as a result of a complex disorder of tubular transport and ion excretion.

Etiology: The disease is caused by abnormalities of three different transport systems : Na + / K + / 2Cl - cotransporter, potassium channel and chloride channel.

Pathogenesis: A defect in the Na + / K + / 2Cl - transporter (NKCC2, ATP-independent ion channel) [2] in the ascending part of the Henle loop of the nephron leads to insufficient sodium absorption and its reduced level in the macula densa increases RAAS activity, which leads to increased levels aldosterone and secondary hyperaldosteronism with all clinical signs (blood pressure is normal).

The clinical picture
The main symptoms include:

Hypokalaemia (severe muscle weakness)

Alkalosis

Hypercalciuria

Growth disorders.

According to the type of defective transport system, we distinguish 5 types of Bartter's syndrome.


 * Type I - Na + / K + / 2Cl - cotransporter defect (NKCC2); manifest already in infancy, mostly premature babies to mothers with polyhydramnios [3]
 * Type II - ATP-dependent apical potassium channel defect (ROMK1); phenotypically the same as type I.
 * Type III - basolateral chloride channel defect; Hypomagnesaemia is observed in 30% of patients (types I and II do not have it) [3]
 * Type IV - β-subunit defect of the basolateral chloride channel; Characteristics: Bartter's syndrome, renal insufficiency, hearing impairment [3].


 * Type V - calcium receptor defect [1] ; Hypocalcaemia occurs with decreased PTH [3].

Therapy: The therapy is only symptomatic.

Prognosis: The prognosis of the disease is uncertain, with some patients experiencing mental retardation or kidney failure.