The most severe form of this disease ( as portrayed in the challenge ) must have given rise to stories of werwolves and vampires - becos a blood-meal containing heme would suppress the heme synthesis pathway. Can you identify this autosomal recessive condition ?
Answer: Congenital Erythropoetic Porphyria - Autosomal recessive - Uroporphyrinogen III cosynthase def. Photosensitivity in this very rare autosomal recessive disorder may begin in infancy. Clinical manifestations include skin and ‘erythron’. Skin – cutaneous lesions such as vesicles & bullae form on light exposed skin which after time of ulceration & erosion cause scarring. The scarring can cause severe defoemities particularly of the face and fingers Other complications include – hypertrichosis, alopecia, conjunctivitis, keratitis. Teeth are red and fluorescent. Erythron – Crystals in RBC cause hemolysis and the most severe forms have given rise to stories of vampires and werwolves ( becos a blood meal would suppress the heme synthesis pathway ). Lab – Urine has port wine color, ↑ uroprphyrin Blood – hemolytic anemia, Bone marrow – normoblastic hyperplasia ( red fluorescence 400 nm ) Feces - ↑ uroprphyrin, ↑ Coproprphyrin Rx - Prophylaxis for skin lesions, Antibiotics for infected skin lesions - Splenectomy to reduce hemolysis & prevent excessive porphyrin production - transfusion will ↓ erythropesis & ↓ porphyrin production - hematin i.v administration has been effective in a few patients as also bone marrow transplantation - β carotene may be tried but not as effective as in protoporphyria. I have posted my notes on porphyria here - http://forum.facmedicine.com/biochemistry/11331-board-cracking-questions-biochemistry.html#post40846
