Guidelines Call for Breastfeeding Exclusion without Actual Milk Allergy Diagnosis

April 14, 2020

A new summary of recent cow's milk allergy guidelines show conlficting consensus on identifying and caring for infantile allergic symptoms.

Robert J. Boyle, MB, ChB, PhD

Despite available data showing ≥99% of infants with cow’s milk allergy (CMA) are capable of tolerating breastmilk from a dairy-consuming women without experiencing an allergic reaction, multiple food allergy guidances with conflicting funding recommend breastmilk be excluded from infants with common, undiagnosed milk allergy symptoms.

A new Special Communication published in JAMA Pediatrics found that a majority of 9 cow’s milk allergy management and care guidelines published since 2012 recommend breastmilk exclusion despite there being limited data proving its benefit in patients with definite allergy. It also showed that 3 guidelines were directly funded by formula company manufacturers or marketing consultants, and more than 80% of all guideline authors had reported a manufacturer-related conflict of interest.

The new study—penned by Robert J. Boyle, MB, ChB, PhD, of the Department of Pediatrics at Imperial College London, and colleagues—comes at a time when clinicians are burdened with the boom of specialized formula products advertised for the management of cow’s milk allergy. This increased market came, Boyle and colleagues wrote, at the time that parents began interpreting crying, vomiting, and rashes more frequently as direct symptoms of undiagnosed cow’s milk allergy.

Despite the obvious supply-demand correlation, there is no proof of increased infantile allergy cases—a large Australian study of approximately 1900 infants found cow’s milk allergies at 12 months may have increased at most by 0.2 percentage points from 1990-1994 to 2006-2010.

“The increase in specialized formula use might represent an example of commercially driven overdiagnosis, where practitioners and parents are encouraged to consider CMA diagnosis and treatment for symptoms that are unlikely to be caused by CMA,” investigators wrote.

The team sought to interpret the evidence for managing common infant symptoms with the exclusion of cow’s milk exposure by reviewing relevant English-based guidelines published since 2012. Their assessment pertained to 2 key recommendations: relevant literature summarizing whether excluding cow’s milk was effective for managing common infant symptoms, and published data on breastmilk composition and the thresholds to reactivity in cow’s milk allergy—to estimate the probability that cow’s milk protein in human breastmilk could even trigger infant allergy symptoms.

In instances where infants presented with the guidelines’ symptoms suggestive of non-immunoglobulin E (IgE)-mediated cow’s milk allergy, 6 (66.6%) of the guidelines advised exclusive breastfeeding. One guideline gave no specific advice, and just 2 (22.2%) advised the continuation of breastfeeding in infants with symptoms suggesting cow’s milk allergy.

One-third (33%) of the guidelines reported direct support from formula manufacturers or marketing consultants; just 1 advised for exclusive breastfeeding. However, investigators observed that 81% of guideline authors had reported a conflict of interest with formula manufacturers.

Boyle and colleagues observed that the probability that an infant with cow’s milk allergy whose mother has consumed 200-700 mL of cow’s milk will suffer an allergic reaction from a large breastfeed is very low—just 3 of 174 women (1.7%) who provided >600 samples for analysis had ≥1 sample with sufficient beta-lactaglobulin (BLG) levels to trigger an allergic reaction in infants in the first percentile of sensitivity with cow’s milk allergy.

Cow’s milk avoidance is important in cases of an allergy being present, investigators wrote—but clinical trial evidence does not support maternal or infant dietary exclusions for managing common symptoms when a proven cow’s milk allergy is not available. Their findings, showing a little-evidenced guidance to the contrary, indicates unwelcome outside factors directing clinical decision-making.

“When industry is closely involved in education, guideline development, and dissemination, we should not be wholly surprised that trends in diagnosis and treatment favor use of their products,” they concluded. “Formula manufacturers may gain from promoting increased CMA diagnosis by influencing practitioners and parents to use a specialized formula in place of a cheaper formula and by potentially undermining women’s confidence in breastfeeding so that specialized formula is used in place of breastmilk.”

The team called for the dissociation of development and dissemination of such observed guidelines from industries capable of profiting from their advisory, and for the continued work between clinicians, patients, and mothers to more concisely identify and treat cow’s milk allergy.

The article, “Assessment of Evidence About Common Infant Symptoms and Cow’s Milk Allergy,” was published online in JAMA Pediatrics.