Rare Hyperpigmentation of the Conjunctiva and Sclera: Ochronosis

Introduction

Alkaptonuria is a rare autosomal recessive disorder in which the metabolism of tyrosine is not properly functioning [1], [2] as a result of loss of homogentisate 1,2 dioxygenase (HGO) activity [3]. It has an estimated prevalence of 1 – 9/1.000.000 [4], [5], [6]. Literature suggests that the most common clinical finding is hyperpigmentation of the sclera [7], followed by conjunctival pigmentation and pigmented chamber angle, whereas recurrent anterior uveitis is a rare finding. Here, we present a case of a patient with this clinical condition.

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