Medullary sponge kidney presenting with hypokalaemic paralysis

Area of Science:

• Nephrology
• Genetics
• Endocrinology

Background:

• Medullary sponge kidney (MSK) is a congenital renal malformation.
• It is often asymptomatic and discovered incidentally.
• Associated urinary acidification defects are rare and usually clinically insignificant.

Observation:

• A rare case of medullary sponge kidney was identified.
• The patient presented with hypokalaemic paralysis.
• This presentation was linked to congenital distal renal tubular acidosis.

Findings:

• Congenital distal renal tubular acidosis (dRTA) can manifest with severe electrolyte disturbances.
• Hypokalaemia, a key feature of dRTA, can lead to neuromuscular complications like paralysis.
• The co-occurrence of MSK and dRTA, though rare, underscores the complex pathophysiology of renal tubular disorders.

Implications:

• This case expands the clinical spectrum of medullary sponge kidney.
• It emphasizes the importance of considering metabolic derangements in patients with MSK.
• Early diagnosis and management of dRTA are crucial to prevent severe complications such as paralysis.