Gullner Syndrome

At a glance

An inherited medical condition similar to ☞Bartter Syndrome, presenting with normal juxtaglomerular apparatus and abnormalities in the proximal renal tubule. Hypokalemia and dehydration are present.

Synonym

Familial Hypokalemic Alkalosis with Specific Renal Tubulopathy Syndrome.

History

This medical condition was first described by H. G. Gullner in 1979.

Incidence

Fewer than 10 cases have been described.

Genetic inheritance

Autosomal recessive.

Pathophysiology

Unknown. Hypokalemia is corrected by magnesium repletion, suggesting an interrelationship of magnesium and potassium metabolism.

Diagnosis

Clinically evocated by signs of hypokalemia and confirmed by biologic studies.

Clinical aspects

Fatigue and muscle cramps are the main features; they are associated with nausea and intermittent vomiting. Laboratory findings include hypokalemic alkalosis, abnormal magnesium metabolism, resistance of blood vessels to angiotensin II, sodium wasting by proximal tubular defect, elevated plasma renin, and elevated prostaglandin E₂ levels.

Precautions before anesthesia

Evaluate hypokalemia and hydration (clinical, electrolytes, creatinine, and urea serum levels).

Anesthetic considerations

Hypokalemia and dehydration should be corrected before anesthesia is performed. Central venous catheterization may lead to cardiac rhythm disorder by direct endocavitary stimulation. Avoid advancement of the guidewire into the heart during central venous catheter insertion since endocavitary mechanical stimulation of the heart may easily trigger cardiac arrhythmias in these patients. Close perioperative monitoring of heart rhythm and hemodynamics is recommended.

Pharmacological implications

Care with use of bicarbonate, insulin, β₂-agonists or other drugs that could lower potassium serum levels. Try to avoid drugs that primarily rely on renal function for elimination or dose appropriately.

Other conditions to be considered

• ☞Bartter Syndrome: Characterized by failure to thrive, growth deficiency, dwarfism, muscle weakness and cramps, and hypokalemia as a result of a Renal Potassium Wasting Syndrome. Mental retardation has been observed in some patients. An acid-base imbalance associated with hypokalemic alkalosis is pathognomonic of the condition. Low potassium levels may result from hyperaldosteronism. The exact cause is not known, but inheritance as an autosomal recessive trait has been suggested.

• ☞Gitelman Syndrome: Inherited renal tubular defect resulting in urinary loss of magnesium, sodium, potassium, and chloride with otherwise normal kidneys.

References