描述
Hereditary coproporphyria (HCP) is caused by a defect in the CPOX gene which codes for mitochondrial coproporphyrinogen-III oxidase. A defect in this enzyme results in accumulation of the porphyrin precursors porphobilinogen and 5-aminolevulinic acid; increase of fecal and urinary excreation of coproporphyrins. Symtpoms include reddish-purple urine, acute neurological problems (typically episodic confusion and sensory changes), and attacks of acute abdominal/nerve pain. Around 30% suffer photosensitive skin eruptions with nail involvement; these can lead to permanent scarring. While there is no cure for this condition, there are preventative measures people can take to regulate symptoms. A diet high in carbohydrates, glucose, as well as avoidance of aggravating factors (such as alcohol and drug use) can prevent attacks.