Page 48 - Livre électronique des RFTP 2024

P3. NEW APPROACHES : BASOPHIL ACTIVATION TEST

(BAT) AS A BIOMARKER OF CLINICAL RESPONSE TO
SUBLINGUAL IMMUNOTHERAPY

A. SAIDANE 1,*, S. DABOUSSI 1, S. MHAMDI 1, R. MZOUGHI 2, C. AICHAOUIA 1, S.
SAMMOUD 3, E. GHAZOUANI 2, Z. MOATEMRI 1,*.

1- SERVICE DE PNEUMOLOGIE-HOPITAL MILITAIRE - TUNIS (TUNISIE), 2- SERVICE
D'IMMUNOLOGIE-HOPITAL MILITAIRE - TUNIS (TUNISIE), 3- SERVICE D'IMMUNOLOGIE-INSTITUT
PASTEUR - TUNIS (TUNISIE)

INTRODUCTION

The Basophil Activation Test ; which measures the activation of basophils after
exposure to the causal allergen ; has emerged as a rigourous tool in the diagnosis
and severity evaluation of the IgE-mediated allergic diseases as well as in the
assessement of tallergenic immunotherapy efficiency .

AIM OF THE WORK :
We aimed to highlight the clinical relevance of Basophil Activation Test as a
biomarker of good response to the sublingual immunotherapy (SLIT) in house dust
mites- allergic patients .

METHODS :

It is a prospective study including stable house dust mites (HDM)-allergic patients
confirmed with a prick skin test.They were divided in 2 groups.The first group (G1)
had received SLIT with the symptomatic treatement and (G2) was put under
pharmacological treatement only.We assessed SLIT efficiency using a symptom
and a medication score. The total serum specific HDM IgE and IgG4 levels were
quantified in the Pasteur Institute.We also performed Basophil activation test (BAT)
using the CD 63 surface marker by flow cytometry.

RESULTS :

We enrolled 32 patients in G1 patients with a mean age of 21 years and 13 patients
with a mean age of 26.7 years in G2. As regards the atopic manifestations,30 cases
had an associated allegic rhinitis in G1 , 22 cases an associated allergic asthma, 15
cases an associated allergic cunjunctivities and just one case an associated allergic
dermatities. Most of them reported a regular SLIT intake (83.3%).A significant clinical
improvement was reported in most cases (80.6%). Indeed, a successful interruption
of the treatement was reported in 11 cases among patients with allergic rhinitis and
in two asthma patients.Added to that, we noticed a significant decrease in the daily
dose of the inhaled corticostreroids intake in 12 cases during the follow-up.

As regards the biomarkers, the total serum specific house dust mites IgG4 blocking
antibodies increased in the G1 (p=0.33 g/l) vs (0.004 g/l) in G2.It was consistent with
a good clinical esponse Moreover,we noticed a significant reduction of the

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