Acute peripheral neuropathy due to hereditary coproporphyria

A 23‐year‐old man with epilepsy and a past history of abdominal pain and ileus, developed hypertension and arm and bulbar weakness when valproic acid and carbarnazepine were reinitiated. Electrophysiologic studies demonstrated a peripheral neuropathy with features of axonal degeneration and demyelination. Axonal degeneration was documented by sural nerve biopsy. Markedly elevated urinary 8‐aminolevulinic acid and porphobilinogen indicated a diagnosis of acute porphyria. Other laboratory studies were most consistent with hereditary coproporphyria. Motor function improved considerably but incompletely over 1 year. An acute, primarily motor neuropathy can occur in several forms of porphyria, including acute intermittent porphyria, variegate porphyria, and hereditary coproporphyria, sometimes even in the absence of concomitant gastrointestinal symptoms. © 1994 John Wiley & Sons, Inc.