In patients with cow's milk allergy retrospective evaluation of factors affecting tolerance development

Food allergy is an important public health problem that affects children and adults and its prevalence is increasing. Cow's milk allergy is a common food allergy in infants and young children, affecting 2-3% of the general population. It has been reported that symptoms of food allergy in childhood are most commonly seen in the first two years of life, and tolerance usually develops by late childhood. In our study, the clinical and demographic characteristics of the patients aged between 1 and 12 years (minimum 12 months, maximum 115 months) who were followed up with the diagnosis of cow's milk allergy at the Tekirdağ Namık Kemal University Pediatric Allergy and Immunology outpatient clinic, and their laboratory tests evaluated for diagnostic purposes and during follow-up were retrospectively examined from the patient records. It was aimed to investigate the factors affecting the development of tolerance in milk allergy. While 9.4% (n=14) of the cases developed tolerance before the age of 2, 45.6% (n=68) developed tolerance after the age of 2; 45.0% (n=67) still have not developed tolerance. When looking at the distribution of tolerance development according to age in patients followed with a diagnosis of CMA during the study, cumulatively; Tolerance at 1 year of age is 9.4% (n=14) of patients, tolerance at 2 years of age is 55% (n=82) of patients, tolerance at 3 years of age is 81.9% (n=120), tolerance at 4 years of age (85.2%; n= 127), tolerance developed in patients aged 5 years (88.5%; n=132) and in patients older than 5 years (91.2%; n=137). Tolerance had not yet developed in 12 patients (8%) evaluated during the study period. When patients with tolerance development at 2 years of age were compared with patients without tolerance development at 2 years of age; Gender (p=0.699), time of first complaint (p=0.142), presence of concomitant atopic disease (p=0.17), family history of atopy (p=0.225), presence of asthma (p=0.72), GI symptoms there was no significant difference between the two groups in terms of presence of food allergies (p=0.1), presence of multiple food allergies (p=0.24), and paternal age (p=0.02). A history of cesarean section was more common in patients who did not develop tolerance at the age of two (p = 0.025); follow-up period is longer (p<0.001); Total IgE (p=0.001), CM-sIgE (p=0.001) and CM swelling diameter in SPT (p= p=0.001) were higher in laboratory tests; maternal age (p=0.007) higher; presence of accompanying AR (p=0.002) more frequently; Vitamin D level is lower; accompanying vitamin D deficiency is more common (p=0.025). Cow's milk allergy is among the common food allergies in infants and early childhood. A wide spectrum of clinical findings may occur due to cow's milk intake, ranging from findings such as urticaria/angioedema to life-threatening reactions such as anaphylaxis. It is important to evaluate the patients by determining the factors affecting the development of tolerance in these patients to avoid unnecessary elimination diet. In this study, in patients who did not develop tolerance at the age of 2 years, concomitant AR was more common, maternal age was older, vitamin D level was low, Total IgE was high, CM-sIgE was high, CM swelling age on SPT was higher, compared to patients who developed tolerance at the age of 2 years has been detected. Keywords: Cow's milk allergy, Tolerance development, sIgE, SPT