Therapy | Schwartz-Bartter Syndrome

Therapy

The therapy of the triggering underlying disease is in the foreground. After successful therapy, there is usually a spontaneous healing (spontaneous remission) of Schwartz-Bartter syndrome. The symptomatic therapy of Schwartz-Bartter syndrome consists of a restriction of drinking (water restriction), which alone usually leads to an improvement of the symptoms.

In addition, a slow infusion of isotonic (0.9%) or hypertonic (10%) saline solution (sodium chloride solution) can be given to compensate for hyponatremia. If the saline solution is infused too quickly, this can lead to disturbances of consciousness, seizures or central pontine myelinolysis, in which damage to the sheath (myelin sheath) of nerve fibers, especially in the brainstem (pons), occurs. It should also be noted that hyponatremia is usually accompanied by hypokalemia, i.e. a lack of potassium in the blood.

For this reason, potassium should be given in addition, which releases sodium from the cells and thus helps to compensate for hyponatremia in the extracellular space. In the case of water intoxication, in addition to hypertonic saline solution, furosemide (Lasix®), a loop diuretic, can also be given to flush water out of the body. Schwartz-Bartter syndrome can be treated with direct ADH antagonists, known as vaptans. Vaptans attach themselves to the ADH receptors in the kidney, thus blocking the action of ADH and promoting the excretion of electrolyte-free water. In August 2009, Tolvaptan became the first and so far only oral ADH antagonist available in Germany.

Prognosis

Successful therapy of the underlying disease usually leads to spontaneous healing of Schwartz-Bartter syndrome. Thus, the prognosis depends strongly on the cause of the syndrome.

Summary

Schwartz-Bartter syndrome is caused by inadequately increased ADH secretion with water retention and hyponatremia. It usually occurs as a paraneoplastic syndrome in small cell bronchial carcinomas, but can also occur in central nervous disorders, infections or as a side effect of certain drugs. Symptoms include reduced urine excretion, weight gain, dizziness, nausea, loss of consciousness and seizures.

Laboratory diagnostics show a highly concentrated urine (high urinosmolality) and an unreasonably high sodium concentration in the urine. On the other hand, there is a dilution in the blood (low plasma osmolality) with hyponatremia. The therapy of the underlying disease is the main focus. Symptomatically, Schwartz-Bartter syndrome is treated with fluid restriction and compensation of hyponatremia with saline solution.