To the Editor: A 4-y-6-mo-old male child presented with daily abdominal pain for 2 y, which had increased in frequency and severity for the last 6 mo. The pain would typically start 5–10 min after meal, around the periumbilical and epigastric region and lasted for 20–30 min. He would also develop abdominal distension after meals, which would subside within 2–3 h. He had a history of alternate diarrhea and constipation, recurrent urticaria, recurrent oral ulcers, and vomiting. These symptoms would aggravate on eating fish, egg yolk, mango, apple, and sapodilla. His serum immunoglobulins showed a marked increase inIgE [401 mg/dL (0–40 mg/dL)]. Antiendomysial antibody, tTG IgA, urinary porphobilinogen, HIV ELISA were negative. Endoscopy was not done. On specific IgE food allergy test (fluroenzyme immunoassay), potato allergen IgE was positive (3 kUA/L) (> 0.1 is positive), whereas no allergy was detected for apple, egg white, and fish. The child was advised to avoid potato, avocado, banana, tomato, kiwi, and chestnut (cross reactivity) and was advised to take symptomatic treatment for the reaction, following which his symptoms resolved.

Allergic reactions to food allergy may be IgE or non-IgE-mediated. Mild reactions usually manifest as a rash, itching, hives, nasal congestion, and oral allergy syndrome, while a severe reaction manifests as anaphylaxis. IgE-mediated reactions are caused due to increased permeability of the vessels leading to increased permeability of vessels. In non-IgE-mediated reactions, allergen-specific lymphocytes and IgG antibodies facilitate the inflammation.

The workup for suspected food allergy includes the skin-prick testing, the measurement of food-specific immunoglobulin E antibodies, and atopy patch test [1]. The skin-prick test has excellent negative predictive values but the diagnostic value remains controversial [2]. A study done in 141 children showed that patch test was more sensitive than the skin-prick test in diagnosing food allergy [3].