Recurrent symptomatic urolithiasis in a patient with cystic fibrosis

Area of Science:

• Pediatric Nephrology
• Medical Genetics
• Rare Diseases

Background:

• Cystic Fibrosis (CF) is a genetic disorder affecting multiple organs.
• Nephrolithiasis (kidney stones) can be a complication in CF patients.
• Consanguinity increases the risk of rare genetic conditions.

Observation:

• A 6-month-old girl with CF presented with recurrent nephrolithiasis and urinary tract infections.
• Despite treatment, stone burden persisted, prompting further investigation.
• Initial metabolic workup excluded cystinuria but indicated hyperoxaluria.

Findings:

• Genetic testing identified a homozygous variant in the AGXT gene, confirming Primary Hyperoxaluria type 1.
• The patient had two rare, life-threatening genetic diseases concurrently.
• High urinary oxalate excretion was noted, consistent with secondary hyperoxaluria in CF.

Implications:

• This case highlights the importance of genetic testing in consanguineous families with early-onset nephrolithiasis.
• Simultaneous diagnosis of two rare genetic disorders presents unique clinical challenges.
• Early identification of Primary Hyperoxaluria type 1 is crucial for timely management and preventing renal damage.