What are triggers of PCT?

• Clinical expression of both sporadic and familial PCT most often requires exposure to environmental or infectious agents or the presence of coexisting conditions that adversely affect hepatocytes and result in hepatic siderosis. • Ethanol intake, estrogen therapies, hemochromatosis genes, and hepatitis and HIV infections are among these contributory factors • Excess iron enhances formation of toxic oxygen species, increasing oxidative stress and apparently facilitating porphyrinogenesis by catalyzing the formation of oxidation products that inhibit UROD • Reduction of hepatic UROD activity to approximately 25% of normal is required for clinical disease expression