Bartter syndrome presenting as poor weight gain and abdominal mass in an infant

Area of Science:

• Nephrology
• Genetics
• Pediatric Medicine

Background:

• Bartter syndrome comprises genetic defects leading to similar clinical presentations, classified into six genotypes and three phenotypes.
• Key laboratory findings include hypochloremia, hypokalemia, metabolic alkalosis, and excessive chloride/potassium excretion.
• The main clinical variants are Classic Bartter syndrome, Neonatal Bartter syndrome, and Gitelman syndrome, differing in gene defects and affected kidney tubules.

Observation:

• Classic and Neonatal Bartter syndromes involve defects in the ascending loop of Henle's transport channels.
• Gitelman syndrome, a milder variant, stems from defects in the distal convoluted tubule's transport channels.
• Gitelman syndrome is distinguished by hypomagnesemia and normal/low calcium excretion, unlike the other variants.

Findings:

• This case presents a 6-month-old boy with Bartter syndrome, exhibiting poor weight gain and an abdominal mass.
• The patient's presentation highlights the varied clinical manifestations of Bartter syndrome in infants.
• Diagnostic challenges in pediatric Bartter syndrome underscore the need for comprehensive evaluation.

Implications:

• Early identification and management of Bartter syndrome are vital for favorable patient outcomes.
• Untreated Bartter syndrome can progress to tubulointerstitial nephritis and end-stage renal disease.
• Understanding the distinct genetic and clinical features of Bartter syndrome variants aids in targeted therapeutic strategies.