Alkaptonuria
What are the symptoms?
Alkaptonuria may discolour the outer ears, nose and whites of the eyes with bluish-black pigment. Vision is not affected. The teeth and nails may also be a bluish-black colour. A dusky discolouration on the skin of the hands may be apparent. Pigment appears when individuals perspire, causing discolouration of clothing.
HGA accumulated in the urine causes this to turn black. Darkening may not occur for several hours after urinating and many individuals never observe any abnormal colour in their urine.
In later life, Alkaptonuria may affect the heart, kidney and prostate. The condition does not cause developmental delay or cognitive impairment and lifespan of affected individuals is generally not reduced.