Atypical attack of acute intermittent porphyria – paresis but no abdominal pain

.  Andersson C, Nilsson A, Bäckström T (University Hospital, Umeå, Sweden; and Primary Health Care Centre, Arvidsjaur). Atypical attack of acute intermittent porphyria – paresis but no abdominal pain (Case report). J Intern Med 2002; 252: 265–270. We report a case of acute intermittent porphyria (AIP) in a 45‐year‐old woman. Her first attack occurred at the age of 38. Because of escalating cyclical premenstrual attacks, the following 2 years, depletion of the endogenous sex hormone was considered as haeme arginate treatment proved insufficient. Gonadotropin releasing hormone agonist treatment with low‐dose oestradiol add back was quite successful initially but was abandoned after 18 months when progesterone add back precipitated a severe attack. Following hysterectomy and oophorectomy at age 42 and oestradiol add back, a remarkable monthly regularity of attacks ensured periodically but with milder symptoms. Two years after surgery, preceded by six attack‐free months, a puzzling symptom‐shift occurred, from abdominal pain, back and thigh pain during the attacks, to solely severe distal extensor paresis in the arms. Haeme arginate treatment interrupted the progress of the paresis almost immediately and motor function improved considerably up to the 9‐month follow‐up. Electrophysiological examination revealed only motor neuropathy, consistent with axonal degeneration. Subsequently the symptoms changed yet again, to sensory disturbances with numbness and dysesthesia as the primary expression followed by rather mild abdominal pain. However, cyclical attacks occurred, despite absence of endogenous ovarial hormone production, possibly attributable to impaired oestrogen metabolism in the liver, or adrenal oestrogen production. Treatment comprising oophorectomy, low‐dose oestradiol add back and haeme arginate infusion for 2 days on the appearance of early AIP symptoms is now quite successful affording improvement in life quality.