Clinical presentation of 13 children with alkaptonuria

Area of Science:

• Pediatric rare diseases
• Metabolic disorders
• Genetics

Background:

• Alkaptonuria (AKU) is a rare genetic disorder.
• Few studies have focused on early AKU symptoms in children.
• Comprehensive assessment of pediatric AKU is needed.

Purpose of the Study:

• To comprehensively assess early-onset alkaptonuria (AKU) in children.
• To evaluate clinical, imaging, cognitive, and genetic aspects of pediatric AKU.
• To identify common symptoms and genetic variants in young AKU patients.

Main Methods:

• Prospective, longitudinal study of 13 pediatric AKU patients (4-17 years).
• Clinical evaluation including pigmentation, musculoskeletal, cognitive, and adaptive abilities.
• Magnetic resonance imaging (MRI), ultrasound (US), and molecular genetic analyses.

Main Results:

• Dark urine (100%), joint pain (46%), and dark ear wax (46%) were most common.
• Cognitive deficits/adaptive ability issues found in 38% of patients.
• No degenerative knee changes on MRI/US; one case of nephrolithiasis.

Conclusions:

• Pediatric AKU presents with characteristic symptoms and potential cognitive impacts.
• Early AKU assessment should include clinical, imaging, and cognitive evaluations.
• Common HGD variants and a novel potentially pathogenic allele were identified.