Crystalline Inclusions in Hepatocyte Mitochondria of a Patient with Porphyria Cutanea Tarda

Intramitochondrial crystalline inclusions were found in hepatocytes of a patient with porphyria cutanea tarda (PCT). They were composed of parallel filamentous structures which measured approximately 12 nm in diameter. Each filament was separated from an adjacent filament by a space measuring approximately 5 nm. The mitochondria containing such inclusions were usually elongated and enlarged. It seemed likely that these changes are not particular in PCT, but indicate one reversible pathological finding in the liver.