From the Guidelines
Acquired Bartter syndrome should be managed by addressing the underlying cause and providing potassium supplementation, potassium-sparing diuretics, and NSAIDs as needed, with regular monitoring of electrolytes, kidney function, and blood pressure, as recommended by the European Rare Kidney Disease Reference Network Working Group for Tubular Disorders 1.
Key Considerations
- Acquired Bartter syndrome is a rare kidney disorder characterized by electrolyte imbalances, particularly potassium loss, metabolic alkalosis, and normal to low blood pressure.
- Common causes include certain medications (loop diuretics like furosemide, aminoglycosides, cisplatin), autoimmune disorders, kidney diseases, and excessive licorice consumption.
- Treatment focuses on addressing the underlying cause while managing symptoms, with potassium supplementation (40-100 mEq daily) typically needed, along with potassium-sparing diuretics such as spironolactone (25-100 mg daily) or amiloride (5-10 mg daily) 1.
- NSAIDs like indomethacin (25-50 mg three times daily) may help reduce prostaglandin production, which contributes to potassium wasting, as supported by the European Rare Kidney Disease Reference Network Working Group for Tubular Disorders 1.
- Magnesium supplements are often required as magnesium deficiency frequently accompanies this condition, and regular monitoring of electrolytes, kidney function, and blood pressure is essential.
Pathophysiology and Genetics
- The pathophysiology of Bartter syndrome involves impaired salt reabsorption in the thick ascending limb, leading to a reduction of calcium reabsorption and hypercalciuria, as well as a progressive reduction or complete blunting of the osmotic gradient in the renal medulla, causing isosthenuria 1.
- Five different causative genes have been identified, encoding proteins directly involved in salt reabsorption in the thick ascending limb (BS1–4) or regulating their expression (BS5), with the mode of inheritance being autosomal recessive in BS1–4 and X-linked recessive in BS5 1.
Diagnosis and Management
- Genetic testing for Bartter syndrome should include genes such as SLC12A1, KCNJ1, CLCNKB, CLCNKA, BSND, and MAGED2, as recommended by the European Rare Kidney Disease Reference Network Working Group for Tubular Disorders 1.
- Maternal treatment with NSAIDs can be considered in cases of polyhydramnios secondary to Bartter syndrome, but close monitoring with fetal echocardiography is mandatory due to the risks of fetal ductus arteriosus constriction and other complications 1.
- Regular monitoring of electrolytes, kidney function, and blood pressure is essential, and the prognosis is generally favorable if the underlying cause can be identified and eliminated, allowing the kidneys to recover normal function, as supported by the European Rare Kidney Disease Reference Network Working Group for Tubular Disorders 1.
From the Research
Definition and Causes of Acquired Bartter Syndrome
- Acquired Bartter syndrome is a rare condition that can be caused by various factors, including autoimmune disorders, endocrine diseases, and connective tissue diseases 2.
- It can also be associated with other conditions such as sarcoidosis, which can lead to a Bartter-like syndrome 3.
- The syndrome is characterized by hypokalemia, metabolic alkalosis, and salt wasting, similar to the inherited form of Bartter syndrome 4, 5.
Clinical Presentation and Diagnosis
- The clinical presentation of acquired Bartter syndrome includes symptoms such as neuromuscular weakness, polyuria, dehydration, and hypokalemia 2, 5.
- Diagnosis is based on a detailed serum and urinary biochemistry analysis, as well as the exclusion of other causes of potassium wasting 2.
- Genetic testing may be necessary to rule out inherited forms of Bartter syndrome or other related conditions 3.
Treatment and Management
- Treatment of acquired Bartter syndrome focuses on correcting dehydration and electrolyte disturbances, as well as reducing polyuria 5.
- Medications such as nonsteroidal anti-inflammatory drugs, potassium supplements, and aldosterone antagonists may be used to manage the condition 2, 3.
- In some cases, steroid-based regimens may be effective in resolving symptoms and correcting electrolyte derangements 2.