Oral immunotherapy in cow's milk allergic patients: course and long-term outcome according to asthma status.

BACKGROUND

Patients with asthma and food allergy comprise a high-risk group for life-threatening reactions at accidental exposure.

OBJECTIVE

To examine the course and long-term outcome of patients with asthma completing milk oral immunotherapy.

METHODS

Children at least 6 years old with (n = 101) and without (n = 93) asthma and IgE-mediated cow's milk allergy, undergoing milk oral immunotherapy from April 2010 to December 2011, were compared. Milk dose escalations were performed until patients reached full (>7.2 g of milk protein) or partial desensitization. Skin prick tests in all patients and spirometry in those with asthma were performed. Patients who completed treatment were followed for longer than 6 months.

RESULTS

Before immunotherapy, patients with asthma, regardless of severity, had more anaphylactic reactions (84.2% vs 64.5%, P = .003), emergency department visits (68.3% vs 51.6%, P = .02), and hospital admissions (32.7% vs 18.3%, P = .03) compared with patients without asthma. Patients with asthma, regardless of severity, had more reactions and injectable epinephrine use during induction (P = .004) and home treatments (P = .007) of immunotherapy. Moderate to severe asthma was associated with a lower likelihood of reaching full desensitization (51.5% vs 68.8%, P = .019), but most patients with asthma (87 of 101, 86.1%), regardless of severity, reached a dose likely to protect them against accidental exposure. Most patients with asthma continued to consume milk protein freely after completion of immunotherapy. Although adverse reactions were still observed, severe reactions appeared to subside with time.

CONCLUSION

Patients with asthma are at risk for more severe reactions and are less likely to reach full desensitization during food oral immunotherapy. However, most reach limited daily consumption and most who achieve full desensitization continue to consume milk protein freely after treatment.