A case of porphyria cutanea tarda in the setting of hepatitis C infection and tobacco usage.

Porphyria cutanea tarda (PCT) is the most common type of porphyria, presenting in middle-aged patients with a photodistributed vesiculobullous eruption, milia, and scars. Porphyria cutanea tarda occurs in relation to inhibition of uroporphyrinogen decarboxylase, a key enzyme in the heme biosynthesis pathway. A number of genetic and acquired factors increase susceptibility to PCT by reducing uroporphyrinogen decarboxylase activity. A handful of other vesiculobullous conditions may mimic PCT both clinically and histologically; therefore, both skin biopsy and laboratory evaluation are helpful in confirming the diagnosis. We report a case of PCT in the setting of cigarette usage and untreated hepatitis C infection.

Central nervous system of a thoracopagus.

Postmortem examination of the central nervous system (CNS) of a dicephalus thoracopagus tetrapus revealed two separate brains and spinal cords. On the conjoined side the spinal cord showed hypoplasia of the anterior horns and dorsal funiculi at the lower cervical and upper thoracic levels. Hypoplasia of the peripheral nerves, anterior horn cells, and dorsal funiculi is a consequence of a reduction in tissue mass due to a loss of inductive influence.