Delete
Are you sure you want to delete this?
Card
-
Title
-
Alkaptonuria
-
ImagePath
-
-
System
-
amino acid metabolism − tyrosine (homogentisate dioxygenase)
-
Overview
-
AR deficiency of homogentisate oxidase → accumulation of homogentisic acid.
-
Pathophysiology
-
Pigment deposits in connective tissue (ochronosis); polymer deposition in cartilage & heart valves.
-
Presentation
-
Bluish‑black sclerae & ear cartilage, dark urine on standing, arthropathy of large joints in adulthood.
-
Diagnosis
-
↑ homogentisic acid in urine/plasma; HGD gene sequencing.
-
Management
-
Low‑protein diet restricting Phe & Tyr; nitisinone inhibits upstream pathway; NSAIDs for pain.
-
Epidemiology
-
Rare; higher in Slovakia & Dominican Republic.
-
Tags
-