MONTREAL – The incidence of cow’s milk protein allergy during the first few months of life may be much more common than suggested by published studies, based on what was found is a prospective study with 700 infants seen regularly at a single, general pediatrics practice in suburban Massachusetts.
Among the 700 infants enrolled in this series, 105 (15%) were diagnosed with cow’s milk protein allergy (CMPA) when they were 5-163 days old, with a median age at diagnosis of 33 days, Victoria J. Martin, MD, said at the World Congress of Pediatric Gastroenterology, Hepatology, and Nutrition. She and her associates confirmed that all these infants had true CMPA episodes of proctocolitis by requiring detection of blood in the stool of affected children.
Mitchel L. Zoler/Frontline Medical News
Dr. Victoria J. Martin
The study results also suggested a protective effect against CMPA when infants received some amount of early breastfeeding, and a pilot substudy run in 47 of the enrolled infants also suggested a link between development of CMPA and abnormalities in the microbiome composition of affected infants, she reported.
While the 15% incidence rate was unexpectedly high, it “absolutely feels like what we see in routine clinical practice,” Dr. Martin said in an interview. She chalked up the much-lower figure cited in the pediatric literature as relying on strict follow-up confirmation by rechallenge of the child with cow’s milk, a step often not taken by busy clinicians. Deferring formal confirmation also often means delayed reintroduction of cow’s milk into the infant’s diet, with restriction often continuing for perhaps a year following the index episode of CMPA. Although such unnecessarily long delays in milk reintroduction have largely been considered benign, recent findings from the Learning Early About Peanut Allergy (LEAP) trial that withholding peanut exposure can increase development of peanut allergies suggests that children also might receive long-term benefit from quicker reintroduction of milk in terms of better development of the immune system and microbiome, she said.
“If we rechallenged all these infants after 1 month, I think we’d find a CMPA rate closer to 3%. Leaving infants on a mild restricted diet for 12 months is a mistake,” she added.
The Gastrointestinal Microbiome & Proctocolitis (GMAP) study enrolled 700 infants seen at a single general practice pediatric practice in suburban Massachusetts at the time of their first well-baby visit, at a median age of 8 days. During 2 years of follow-up, the researchers collected stool specimens from the enrolled children at each of up to five scheduled visits during the first 4 months. They also kept track of when children received a CMPA diagnosis confirmed by at least one bloody stool.
Analysis of CMPA correlates showed that, among infants who developed it, 17% had not received any breastfeeding soon after birth, while among infants who did not develop CMPA, 8% did not undergo early breastfeeding. The incidence of CMPA was roughly similar among infants who received an early combination of breast milk and formula and in those who received exclusively breast milk during the first days of life, showing that even partial breastfeeding is better than no breastfeeding, Dr. Martin noted.
Her analysis also includes initial results from microbial assessment of the collected serial stool specimens from a subgroup of 24 infants who developed CMPA and 23 who did not, with a total of 223 total specimens evaluated. These studies showed that the infants who developed CMPA significantly lagged in their colonization with Bifidobacteria, had significantly higher colonization levels with Enterobacteriaceae, and that in infants who did develop CMPA, their gut level of Clostridia significantly increased as their proctocolitis resolved.
Dr. Martin had no relevant financial disclosures.
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