The investigators would only include the children who received propofol (Propolipid, Fresenius Kabi, Schelle, Belgium) for sedation, the investigators would exclude the children that didn't receive propofol during the procedure.

The investigators would analyze the incidence of hypersensitivity reaction to propofol in children allergic to egg, soy or both egg and soy and to compare those with the incidence of hypersensitivity reactions in children without allergy to egg and/or to soy. Those data were retrieved following longitudinal follow-up after the intervention. Allergy tests by skin and radioallergosorbent tests were performed in all children before the gastrointestinal endoscopy under anesthesia took place, but no results were known at the time of the sedation. A patient was defined as allergic to egg and/or soy if the patient had specific S-IgE level more than the normal level set by our institution (0.35 kU/L).

The investigators would also investigate the influence of other obtained parameters in the dataset (age, ASA score, weight category, type of investigation, respiratory and neurological comorbidities, respiratory infections, GERD, other allergies) on those results with multivariate analysis.

We considered that clinical features suggesting a hypersensitivity reaction present during anaesthesia were cutaneous, respiratory or cardiovascular manifestations. Depending on the severity of the reaction, necessitating prompt hemodynamic resuscitation with the administration of epinephrine, antihistamines, inhaled beta-agonists or corticosteroids.

Inclusion Criteria:

• diagnostic gastrointestinal endoscopy
• monitored anesthesia
• received propofol during the procedure
• allergic to egg and/or soy if the patient had specific S-IgE level more than the normal level set by our institution (0.35 kU/L)

Exclusion Criteria:

• Procedure without administration of propofol

Children who underwent a surgery in UZ Brussels between the period of 01 January 2010 until 31 August 2016.