Recurrent abdominal pain-the forgotten cause.

A 23 year old man presented to the casualty department with right periorbital oedema. A diagnosis of urticaria was made, antihistamines were prescribed, and he was discharged home. Within 24 hours he returned complaining of increased facial swelling and dysphagia, and a medical opinion was sought. He denied recent facial trauma, or insect stings. Further inquiry revealed that he had suVered a similar episode nine months earlier which had involved swelling of his hands and feet. These areas were not itchy or red. His past history included recurrent bouts of abdominal pain associated with distension and vomiting requiring numerous hospital admissions under the care of diVerent consultants over the previous 14 years. A diagnosis of abdominal migraine was frequently recorded. There were no obvious precipitating factors and the bouts resolved spontaneously over a period of a few days. Detailed family history uncovered several members with similar symptoms and an inheritance pattern along the maternal line. Examination revealed a slim built, normotensive 23 year old man with bilateral periorbital, perioral, and pharyngeal oedema. He was comfortable at rest with no drooling, dyspnoea, or wheeze (fig 1). Routine investigations showed a normal full blood count, urea and electrolytes, liver function tests, and chest x ray film. The suspected diagnosis of C1 esterase inhibitor (C1 INH) deficiency was confirmed with low C1 INH and C4 concentrations at 0.08 g/l (normal 0.15–0.35) and <0.06 g/l (normal 0.20–0.60) respectively. In view of the frequency and severity of his symptoms he was started on prophylactic treatment with danazol. He was advised that he would require intravenous infusions of C1 INH concentrate as prophylaxis before any future surgical intervention and review would be needed before future dental work. He was discharged with a Medic Alert bracelet and arrangements were made to screen other family members. To date, three years later, there have been no further relapses. Questions: true or false C1 INH deficiency: (1) Is always associated with peripheral angio-oedema and urticaria. (2) Symptoms can be precipitated by the oral contraceptive pill. (3) Is the most commonly described genetic defect of the complement system and is characterised by a reduction in complement proteins C3 and C4. (4) Is inherited in an autosomal recessive manner and usually presents in the first decade of life. (5) Is primarily treated with fresh frozen plasma which has replaced steroids and antihistamines as the treatment of choice during acute episodes. (6) May be treated by antifibrinolytic drugs, particularly in the acquired variety or in those not responding to androgens. Answers on p 128.