Profilins and Food Dependent Exercise-Induced Anaphylaxis.

The term anaphylaxis defines an acute, life-threatening, generalized reaction with various clinical presentations that affect the skin and respiratory, gastrointestinal, and cardiovascular systems [1-3]. The occurrence of anaphylaxis after physical activity is known as exercise-induced anaphylaxis (EIA). In about a third of cases, cofactors such as food intake, temperature, and drugs (especially nonsteroidal anti-inflammatory drugs) can be identified [4]. When the associated cofactor is food ingestion, the diagnosis is referred to as food-dependent EIA (FDEIA) [1]. Lipid transfer proteins (LTPs) and profilins are panallergens found in many plant foods. LTPs are a common cause of foodinduced anaphylaxis (FIA) in the Mediterranean area and have also been proposed as a main cause of FDEIA [5]. Profilin, on the other hand, is hardly ever involved in the triggering of FIA, and even more rarely in FDEIA. We present 2 cases of this rare condition. Patient 1 was a 12-year-old boy with a personal history of rhinoconjunctivitis and asthma due to allergy to grass pollens. He experienced multiple episodes of FDEIA (urticaria, dyspnea, rhinoconjunctivitis, and abdominal pain) during intense exercise, about 30-90 minutes after eating fruit and/or vegetables (peach, pumpkin, carrot, and tomato) (Table). The patient tolerates all fruits and vegetables if he does not take physical exercise and tolerates physical exercise if he does not eat fruits and vegetables during the previous 4 hours. The allergology study involved skin prick tests (SPTs) with commercial extracts (peach, pumpkin, tomato, wheat, carrot) and prick-prick tests with the fruits and vegetables involved (peach, pumpkin, tomato, carrot, wheat, and pumpkin). All results were positive (mean wheal diameter, >3.3 mm). The results of SPT with commercial extracts of pollens (grass and olive) and purified palm tree profilin were positive. The results of LTP and other pollens and aeroallergens were negative (total IgE, 360 kU/L). Specific IgE (kUA/L) was 75 for rPhl p 1+ rPhl p 5b (Phleum) and 0.6 for rOle e1 (olive). ImmunoCAP (ISAC, results expressed as ISAC standardized units for IgE [ISU-E]) revealed the following values for profilins: Bet v 2, 2.6; rHev b 8, 5.1; and rMer a 1, 3.8. The remaining ISAC determinations were negative. Tryptase was 3.4 μg/L There has been no recurrence of the symptoms of anaphylaxis for the last 5 years, and the patient has avoided intake of fruits and vegetables during the 4 hours before exercise. Patient 2 was a 28-year-old man with a personal history of rhinoconjunctivitis and bronchial asthma due to allergy to grass and olive pollens. He experienced a single episode of FDEIA (urticaria, dyspnea, dizziness, hypotension, and tachycardia) during intense exercise about 60 minutes after eating fruit (peach). While eating, he suddenly experienced oropharyngeal itching, runny nose, and sneezing for about 5 minutes (Table). The patient tolerates physical exercise if he does not eat peach or other vegetables during the 4 hours before exercise and tolerates peach, other fruits, and vegetables if he does not exercise. The allergology study was based on SPTs with commercial extracts (peach, tomato, wheat, carrot) and prick-prick testing with peach and yielded positive results (mean wheal diameter, >3.3 mm). SPTs with pollen extracts (grass and olive pollen and purified palm tree profilin) were all positive. Testing for LTP, other pollens, and aeroallergens was negative. Total IgE was 1180 kU/L. Specific IgE (kUA/L) was 75 for rPhl p 1+rPhl p 5b (Phleum) and 0.6 for rOle e1 (olive). ImmunoCAP (ISAC, results expressed as ISU-E) for profilins was as follows: Bet v 2, 20; rHev b 8, 39; and rMer a 1, 27. The remaining ISAC results were negative. Tryptase was 2.6 μg/L. Table. Demographic, Clinical, and Allergological Characteristics