Acute Intermittent Porphyria: A Report of 3 Cases with Neuropathy.

The porphyrias are metabolic disorders due to a defect in the heme biosynthetic pathway. Patients have diverse clinical presentations with neuropathy being frequent in acute intermittent porphyria (AIP). Associated symptoms are abdominal pain and seizures. Three patients presenting with neuropathy were later diagnosed with AIP on the basis of clinical features, erythrocyte porphobilinogen deaminase activity, neuropathic patterns, and nerve conduction studies. Testing for the HMBS genetic mutation confirmed the diagnosis of AIP in 1 patient. The findings from this case series confirm that porphyric neuropathy in AIP is a predominantly motor neuropathy with differing neuropathic presentations ranging from focal motor neuropathy to quadriplegia and respiratory failure.