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Endogenous ochronosis with a fatal outcome
Inès Zaraa1, Imen Labbène, Sondes Trojjet
1Department of Dermatology, La Rabta Hospital, Tunis, Tunisia. inesrania@yahoo.fr
Journal of Cutaneous Medicine and Surgery
|September 14, 2012
Summary
Endogenous ochronosis (EO) is a rare inherited disorder. Early recognition of skin signs is crucial for detecting vital organ involvement and preventing fatal outcomes like renal failure.
Area of Science:
- Genetics
- Biochemistry
- Dermatology
Background:
- Endogenous ochronosis (EO) is an autosomal recessive inherited disorder.
- It results from incomplete oxidation of tyrosine and phenylalanine due to homogentisic acid oxidase deficiency.
Observation:
- A 46-year-old man presented with slate blue skin pigmentation, nail discoloration, and gum discoloration.
- He had a history of recurrent renal colic and arthropathy.
- Familial investigation revealed similar pigmentation in his sister.
Findings:
- Histopathology showed dermal deposits of acellular, eosinophilic material.
- The patient exhibited mucocutaneous, articular, and renal involvement.
- Diagnosis was delayed, leading to fatal terminal renal failure.
Implications:
- Skin manifestations are key indicators of endogenous ochronosis.
- Clinicians must be vigilant for systemic involvement, particularly of vital organs.
- Timely diagnosis and management are critical for improving patient outcomes.
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