A challenging diagnosis of exercise-related transient abdominal pain

A 17-year-old woman, high-performance triathlete, presented transient abdominal pain, face angioedema and sometimes syncope during exercise. Exercise-induced anaphylaxis was suspected at first. Allergic explorations with skin prick tests were negative but wheat flour specific IgE and recombinant rTri a14 (LTP) were weakly positive. However, wheat eviction did not improve the symptoms and stress test after wheat oral challenge did not show any signs of anaphylaxis. An abdominal ultrasound revealed peak expiratory velocities with a stenosis evaluated at 70 to 80 percent with turbulences in the celiac artery, confirmed by computed tomography angiogram. The diagnosis of exercise-induced median arcuate ligament syndrome (MALS) was retained and we discuss here the challenging diagnosis mimicking exercise-induced anaphylaxis.