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Neglected Alkaptonuric Patient Presenting with Steppage Gait.
Babak Mirzashahi1, Abbas Tafakhori1, Arvin Najafi1
1Joint Research Center, Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran, Iran.
The Archives of Bone and Joint Surgery
|May 21, 2016
Summary
Alkaptonuria (AKU) is a rare genetic disorder. A case report details a 51-year-old male diagnosed with AKU solely through the discovery of a black intervertebral disc during surgery for back pain, a presentation previously undocumented.
Area of Science:
- Medical Genetics
- Biochemistry
- Orthopedics
Background:
- Alkaptonuria (AKU) is a rare autosomal recessive metabolic disorder.
- It results from a deficiency in the enzyme homogentisate 1,2-dioxygenase (HGD).
- This deficiency leads to the accumulation of homogentisic acid (HGA) in the body, causing characteristic ochronosis and tissue damage.
Observation:
- A 51-year-old male presented with chronic low back pain and steppage gait.
- He underwent surgery for a prolapsed lumbar disc herniation.
- Intraoperatively, the intervertebral disc was noted to be black.
Findings:
- Histopathological examination of the black disc material supported the diagnosis.
- Elevated urinary homogentisic acid levels confirmed alkaptonuria.
- This represents an exceptionally rare presentation of AKU, detected solely by disc discoloration.
Implications:
- Highlights the potential for intervertebral disc changes to be the sole presenting sign of alkaptonuria.
- Emphasizes the importance of considering rare metabolic disorders in the differential diagnosis of spinal pathologies.
- Suggests that intraoperative findings can be crucial for diagnosing rare conditions.
