Bartter Syndrome with Normal Aldosterone Level: An Unusual Presentation

Area of Science:

• Nephrology
• Genetics
• Pediatric Medicine

Background:

• Bartter syndrome is a group of inherited renal tubulopathies characterized by salt wasting, hypokalemia, and metabolic alkalosis.
• The primary defect in Bartter syndrome is typically located in the thick ascending limb of the loop of Henle.
• It is often associated with secondary hyperaldosteronism and normal blood pressure.

Observation:

• This report details a pediatric case exhibiting classic Bartter syndrome manifestations, including severe dehydration, profound hypokalemia, metabolic alkalosis, and failure to thrive.
• A key distinguishing feature in this patient was a normal aldosterone level, which is highly atypical for Bartter syndrome.
• The patient's presentation mimicked Bartter syndrome despite the absence of hyperaldosteronism.

Findings:

• The case highlights a potential phenotypic variant of Bartter syndrome.
• The findings suggest that not all cases of Bartter syndrome present with elevated aldosterone levels.
• This observation broadens the diagnostic spectrum for hereditary salt-losing tubulopathies.

Implications:

• This case necessitates a re-evaluation of diagnostic criteria and understanding of the pathophysiology of Bartter syndrome.
• Further research is required to elucidate the genetic and molecular basis of Bartter syndrome variants with normal aldosterone.
• Clinicians should consider a broader differential diagnosis for hypokalemic metabolic alkalosis, even in the presence of normal aldosterone levels.