836:
Early Immunologic Shifts Occurring in Cow’s Milk (CM) Oral Immunotherapy (OIT)
Monday, March 5, 2018
South Hall A2 (Convention Center)
Jose Luiz Rios, MD PhD, Alfredo Alves Neto, Flávia de Carvalho Loyola, Marilúcia Alves da Venda, Amannda Oliveira Rodrigues Andrade, Carolina Oliveira Santos
RATIONALE: Patients with anaphylactic cow’s milk allergy (CMA) have persistent and high levels of specific IgE (sIgE) to milk proteins. OIT induces the sIgE reduction wile increasing specific IgG4 levels. The purpose of this research was follow-up these and other parameters during the induction phase of CM OIT.

METHODS: Series of cases involving 51 children and adolescents with anaphylaxis to CM. SIgE and Total IgG4 levels were evaluated in 2 steps of OIT: at baseline, pre-treatment session (step 1) and when reaching the induction final volume: 300 ml of CM a day (step 2). Time between steps lasted 4 to 6 months. Differences between sIgE levels were analyzed by Paired Student's t test.

RESULTS: At step 1, sIgE mean levels for CM, casein , α-lactoalbumin and β-lactoglobulin were respectively, in KU/L: 56,27 (1,4 - >100.0); 49,38 (0,75 - >100);25,96 (0,1 - >100) and 15,88(0,49 – 86,7).Besides the mean level of total IgG4 was 111,47 KU/l (5,09 - 1020).

At step 2 these values were respectively: 30,49 (0,1 - >100); 25,69 (0.10 - >100); 18,18 (0 - > 100) and 11,6 (0,1 – 56,7). And the total IgG4 mean was 164,94 (5,57 - 3090).

Comparing sIgE and IgG4 means between the steps revealed statistical significance for CM (p<0.0001); casein (p<0.0001); α-lactoalbumin (p=0,02) and β -lactoglobulin (p=0.04); besides IgG4 (p=0,04).

CONCLUSIONS: Milk proteins sIgE levels markedly reduces in few months of CM-OIT, in parallel to developing clinical tolerance to milk ingestion. Increase of total IgG4 levels could mean the increase in specific IgG4 for CM proteins.