Serum ferritin in the assessment of liver iron overload and iron removal therapy in porphyria cutanea tarda

Serum ferritin, an index of iron stores, was studied in 60 patients with porphyria cutanea tarda (PCT), in 21 patients who had other liver diseases without siderosis (cirrhosis [LC] and chronic active hepatitis [CAH]), and in 32 patients with associated liver siderosis (alcoholic LC, LC and CAH in minor thalassemia). Ferritin levels were higher in patients with porphyria than in healthy controls and patients without liver siderosis (P less than 0.001), whereas no statistical difference was observed between patients with porphyria and those with liver siderosis. Because iron removal is considered the treatment of choice for PCT, some patients with PCT underwent phlebotomy and others received chelating therapy with subcutaneous infusion of deferoxamine. Follow-up of the patients showed a correlation between serum ferritin level and urinary porphyrin excretion; when the clinical and biochemical syndrome became normal, serum iron and ferritin had fallen to normal values (t test pair data analysis before and after: P less than 0.001 in each group). No appreciable difference was found between controls and patients with PCT whose conditions had been normalized, irrespective of the chronic liver damage always present in PCT. Our results suggest that serum ferritin increase in PCT is related more to liver iron overload than to liver damage, and ferritin follow-up is recommended to indicate the exhaustion of hepatic iron stores during iron depletion therapy, as well as to detect an early replenishment after remission.