Not a cutaneous porphyria ?

Ans. is 'b' i.e., Hereditary coproporphyria Porphyrias Porphyrias are heterogenous group of disorders characterized by defective metabolism of porphyrins. Porphyrins are impoant intermediates in biosynthesis of heme from glycine and succinyl CoA. Each step is controlled by specific enzyme. So, prophyrias are due to inherited or acquired deficiency of enzymes in heme bio-synthetic pathways (also called porphyrias pathway). They manifest with either neurological complications or skin problems (or rarely both). Based on the site of overproduction and accumulation of porphyrins, porphyrias are broadly classified as :? A. Acute (hepatic prophyria) Acute intermettant porphyria 5-ALA dehydratase deficiency Hereditary Coproporphyria Variegate porphyria Porphyria cutanea tarda B. Cutaneous (erythropoeitic) porphyria Erythropeitic protoporphyria Congenital erythropoeitic porphyria X-linked sideroblastic Anemia The acute (hepatic) porphyrias primarily affect nervous system resulting in abdominal pain, vomiting, acute neuropathy, seizures, muscle weakenss, psychiatric/mental symptoms (i.e., Hallucination, depression, anxiety, paronoia); and autonomic nervous disturbances like hypeension, tachycardia, constipation, arrhythmias, sweating. The cutaneous (erythropoietic) porphyrias primarily affect skin causing photosensitivity (photodermatitis) blisters, itching, maculopapular rash. There is no abdominal pain. There are some variation in above presentation. Following two types of hepatic (acute) porphyrias also affect skin : - Hereditary coproporphyria and varigated porphyria. Therefore these two have both neuropsychiatric as well as skin manifestations. Porphyria cutanea tarda (a hepatic porphyria) does not have neuropsychiatric symptom, rather it has only skin manifestation. X-linked sideroblastic anemia (an erythropoietic porphyria) has neither neuropsychiatric nor skin symptoms.