Other Gastrointestinal Disorders with Unproven Food Allergies
Unexplained paroxysms of crying, irritability and excessive gas have been recorded in 9 to 19% of infants during the first few months of life. The etiology of infantile colic is still not well understood.[28,29] Since approximately 25% of infants with moderate-to-severe symptoms have cow's milk-dependent colic, allergy to cow milk proteins in breast milk or infant's formula have been suggested as a cause of the colic. This was supported by the finding that the use of hydrolyzed formulas was effective in the treatment of colic in some formula-fed infants. In addition, a randomized controlled study in breastfed infants with colic showed a significant number of infants responded to the maternal low-allergen elimination diet compared with the control diet. The study has suggested that the maternally ingested food proteins may be transferred into breast milk and cause colic in breastfed infants. However, in another large prospective study of 983 infants, no evidence of increased risk of atopic manifestations was found in colicky infants. Of note, the majority of studies on dietary interventions, particularly formula-fed infants, concluded that further research is necessary to confirm such findings.[31,32,33]
Cow's milk allergy has been incriminated as a cause of chronic constipation in infants and young children. A high rate of atopic diseases and IgE antibodies have led to the suggestion of an immunologic basis of constipation in a group of patients who responded to substitution of soy-formula or other foods. It has been suggested that a trial of dietary elimination of cow's milk should be undertaken for recalcitrant constipation unresponsive to conventional therapies.[5,27]
Diagnosis of Food Allergy
The diagnosis of food allergy is based mainly on clinical suspicion (Box 3), medical history and clinical examination in order to determine the appropriate diagnostic tests that should be selected according to the underlying immune mechanism of food allergy (Figure 3). The pediatrician who is evaluating an infant or a child with symptoms of GI disease must determine if the case is a true allergy or not and exclude other possible causes of nonimmunologic adverse food reactions. Careful history taking and clinical examination are the cornerstones for the diagnosis of food allergy. History should include queries regarding food taken by the patient, including, which food is thought to have caused the reaction, the state of that food (raw or cooked), the amount of food ingested, the symptoms of the reaction in terms of onset and severity, the reproducibility of symptoms on every occasion,[35,36,37,38] the presence of other allergic manifestations in other target organs (skin and respiratory) (Figure 4), and family history of allergy. Clinical examination should focus on the general health status of the child (growth parameters) and symptoms of allergy in other targets.
General scheme for the diagnosis and management of gastrointestinal food allergy.
APT: Atopy patch test; GERD: Gatroesophageal reflux disease; GIT: Gastrointestinal tract; SPT: Skin-prick test.
Adapted with modifications from [7,37].
When the causal food(s) can not be identified by taking history, the pediatrician should advise the parents to keep a food diary and write down every food ingested by the child in a hope to correlate the symptoms with the food items that are ingested on daily basis. In general, the diagnosis is made on clinical response to allergenic food elimination and oral food challenge (OFC). In children with multiple food allergies, a very restricted diet is often required.
Pediatr Health. 2009;3(3):217-229. © 2009 Future Medicine Ltd.
Cite this: Gastrointestinal Manifestations of Food Allergy - Medscape - Jun 01, 2009.