The goal of this site is to collect the latest information on Allergic Proctocolitis (AP) and make it easily accessible to health care practitioners and families in a way that best supports diagnosis and treatment of infants with this condition. Much of the professional education and patient information contained in these pages will also be applicable to the treatment of other adverse/allergic reactions to dairy and soy proteins.
Allergic Proctocolitis (AP) is an immune mediated gastrointestinal disorder. The most common antigen associated with this disorder is cow’s milk protein, although other food proteins, most notably soy, are also implicated. This condition is often overlooked in differential diagnoses, leading to extended suffering of the infant and family, and unnecessary, expensive, and invasive testing. AP affects both breast and formula fed infants. The majority of cases of AP occur in exclusively breastfed infants reacting to maternal dietary proteins excreted in human milk. Misdiagnosis, misinformation and lack of support greatly increase the potential for early weaning.
The number of women choosing to breastfeed is rising, and a recent increase in outreach, education, and regulatory efforts by medical, governmental and community-based organizations is expected to raise the rate of breastfeeding even higher in the coming years. With this rise in breastfeeding, the number of cases of AP will rise as well. It is essential that physicians, nurses, lactation consultants, dietitians and others involved in the care of breastfed infants and their mothers recognize and understand how to manage this easily-treatable condition.
Allergic Proctocolitis (AP), also known as allergic colitis, dietary protein-induced proctocolitis of infancy, food-induced or benign eosinophilic proctocolitis, or Milk/Soy Protein Intolerance, is an often-overlooked manifestation of dietary protein allergy seen predominantly in breastfed infants.
Cow’s milk protein is considered to be the offending antigen in as many as 50% to 65% of cases. Soy protein is also frequently implicated, being the second most common antigen to cause AP. It is estimated that,30% of patients reacting to cow’s milk concomitantly react to soy protein allergens. Other antigens including egg, corn, cereal grains or multiple foods account for the remainder.
Prospective data indicate that approximately 0.5% to 1% of exclusively breastfed infants develop allergic reactions to cow’s milk proteins excreted in the mother’s milk. While infants fed human milk appear to have a lower incidence of allergic reactions to cow’s milk protein than those fed cow’s milk based formula, more than 50% of infants with AP in published reports were exclusively breast fed. Up to 10 % percent of AP cases have a family history of the same.
Perinatal risk factors such as prematurity, maternal health, and timing of introduction of breast milk or formula appear to play no role in AP.
Allergic Proctocolitis appears in the first 2 months of life, with a range of 1 day to 5 months. Bleeding rarely occurs in the first week of life. The mean age at diagnosis is approximately 60 days.
The pathophysiology of GI related food allergy reactions affecting infants and young children is complex. These reactions can be IgE mediated, partially IgE mediated or non IgE mediated. 50% of children affected by food allergies in the first 2 years of life have non-IgE-mediated reactions. A brief review of food allergy pathogenesis and clinical presentation of the various food allergic conditions that can affect the GI tract in infants and toddlers can be found below. Allergic proctocolitis is a non IgE mediated disorder, and can be differentiated from other food allergic conditions by its presentation and more benign clinical course.