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[First report of alkaptonuria in Peru]
Daniel Guillén-Mendoza1, María Quiroga de Michelena1
1Facultad de Medicina, Universidad Peruana Cayetano Heredia, Lima, Perú
Revista Peruana De Medicina Experimental Y Salud Publica
|January 20, 2015
Summary
Alkaptonuria, a rare metabolic disorder, was diagnosed in a Peruvian woman due to excess homogentisic acid (HGA). This case highlights the importance of recognizing its diverse symptoms, including darkened urine and severe osteoarthritis.
Area of Science:
- Biochemistry
- Genetics
- Metabolic Disorders
Background:
- Alkaptonuria is a rare inherited metabolic disorder resulting from a deficiency in the homogentisate 1,2-dioxygenase (HGD) enzyme.
- This deficiency leads to the accumulation of homogentisic acid (HGA), a metabolic byproduct, in the body.
Observation:
- A 57-year-old woman presented with lifelong dark urine and a 9-year history of greenish nail pigmentation unresponsive to antifungals.
- She experienced progressive, severe osteoarthritis in large joints, necessitating wheelchair use due to hip and lumbar spine pain.
Findings:
- Diagnostic evaluation, including measurement of urinary HGA levels, confirmed the diagnosis of alkaptonuria.
- The patient's clinical presentation, including characteristic symptoms and biochemical markers, aligned with established alkaptonuria profiles.
Implications:
- This case represents the first documented instance of alkaptonuria in Peru, expanding the known geographical distribution of the disorder.
- Management strategies included analgesics, dietary modifications (low tyrosine), and surgical intervention (hip replacement), underscoring a multidisciplinary approach to patient care.
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