alkaptonuria

Ochronosis

Degenerative arthropathy due to Alkaptonuria

Rare hereditary disorder of tyrosine and phenylalanine breakdown

Homogentisic acid enzyme deficiency

- accumulate Homogentisic Acid

- product of tyrosine breakdown

Homogentisic acid deposited in cartilage & other soft tissues

- polymerises

No pathognomonic signs for gout

- identification of negative birefringent crystals under polarising light

- trial of indomethacin if suspected

Crohn's & Ulcerative Colitis

- spinal manifestation similar to Ankylosing Spondylitis

- 15-60% of IBD

Two different forms

- mild & asymptomatic