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Updated: Jul 20, 2025
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Utility of Dissociated Intrinsic Hand Muscle Atrophy in the Diagnosis of Amyotrophic Lateral Sclerosis
Published on: March 4, 2014
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Acute-Onset Multifocal Hand Dysfunction Due to Alkaptonuria.
Brahman Shankar Sivakumar1, Vincent Vin Gia An2, Nicholas Stewart3
1Department of Hand Surgery, Royal North Shore Hospital, St Leonards, New South Wales, Australia.
Journal of Hand Surgery Global Online
|July 31, 2023
Summary
Alkaptonuria can affect the peripheral nervous system, causing carpal and cubital tunnel symptoms. This rare metabolic disorder involves homogentisic acid buildup, impacting nerves rapidly in multiple locations.
Area of Science:
- Neurology
- Metabolic Disorders
- Genetics
Background:
- Alkaptonuria (AKU) is a rare autosomal recessive metabolic disorder.
- Characterized by deficiency of the enzyme homogentisate 1,2-dioxygenase (HGD).
- Leads to accumulation of homogentisic acid (HGA) in various tissues.
Observation:
- Central nervous system (CNS) effects of AKU are documented.
- Peripheral nervous system (PNS) involvement is less commonly described.
- A 72-year-old male with known AKU presented with bilateral carpal tunnel syndrome and left cubital tunnel syndrome.
Findings:
- The patient's rapid onset of symptoms suggests multifocal pathology.
- Homogentisic acid deposition in the peripheral nerves is implicated.
- Nerve compression syndromes may arise from HGA accumulation.
Implications:
- Highlights the potential for significant peripheral nerve pathology in AKU.
- Suggests a need for increased awareness and surveillance of PNS complications in AKU patients.
- May inform future diagnostic and therapeutic strategies for neurological manifestations of AKU.
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