Preliminary data concerning association of porphyria cutanea tarda and adrenocortical insufficiency. Report of two cases.

The paper presents two cases in which clinical and laboratory investigations have revealed the simultaneous presence of porphyria cutanea tarda (PCT) and adrenocortical insufficiency (ACI). Whether this association is a coincidence, whether there is a common cause, or a "cause to effect" type relationship between the two entities is a question of debate. Without ignoring other possible causes (tuberculosis, hemochromatosis, autoimmunity, drugs) it is suggested that heme deficit consequent to inefficient protoporphyrin synthesis results in impaired steroidogenesis, due to decreased levels of adrenocortical hemoprotein enzymes, especially cytochrome P-450 dependent hydroxylases. Cytochrome P-450 has a well known sine-qua-non activity in steroid hydroxylations within steroid tissues, and a decrease in the levels of this heme-enzyme might be expected to result in impaired steroidogenesis. However, the association between PCT and ACI (whether pathogenic or not) is pathophysiologically characterized by the coexistence of a disease (PCT) in which the anatomo-clinical manifestations are determined by oxygen derived free radicals ( ODFR ), and a disease (ACI) which, among other consequences, presents a marked reduction in ODFR -scavenge capacity. The authors consider this supposition an attractive working hypothesis, suitable to further clinical laboratory direct testing.