Pilot study to investigate the value of sensors for early allergic response detection during a food challenge and drug provocation test.

The estimated prevalence of systemic allergic reactions (anaphylaxis) varies
between 0.3-5.1 %. A challenging aspect of food allergies and drug allergies is
adequately diagnosing the presence and in particular the severity of the
allergies.The clinical golden standard for diagnosing food allergy is a food
challenge and for drug allergy it is a drug provocation test. However,
provocation tests are often stressful for the patient, costly, time consuming
and can only be performed in a specialized clinical setting due to the possible
occurrence of a severe allergic reaction. In a previous study we demonstrated
that, despite strict adherence to guidelines, there is a considerable amount of
variability in the conclusion of provocation tests between and within
welltrained clinicians, especially when subjective symptoms occur.
Even severe allergic symptoms often start with mild subjective symptoms, such
as itching in the mouth/oral cavity, itchy skin,sensation of swelling of the
throat, restlessness, followed by mild objective symptoms, that might initially
go undetected, like nasal congestion, dyspnoea, increased sweating, drop of
blood pressure etc. These symptoms can evolve into a severe allergic
reaction.Wearable sensors could offer the opportunity to detect such symptoms
in an early phase, but are mostly in an experimental phase and not specifically
designed to detect early allergic symptoms. It is of great interest to
investigate the potential of these technologies in a clinical setting for
detection of early symptoms of allergic reactions.
Novel diagnostic tools would increase the transparency of the procedure and
might be helpful in assessing the provocation test. This would be of enormous
benefit to patient and health care professionals.

To investigate the potential of the Checkpoint Cardio system in the early
detection of signals that can predict and warn for an allergic reaction.

This is an exploratory study.
Patients with suspected food- or drug allergy from the adult outpatient
population of the department of dermatology/allergology of UMC Utrecht, who
undergo a provocation test as part of routine care, will be asked to
participate in the study. During a provocation test of the challenged food or
will be given. The patients will be monitored continuously using the wireless
Checkpoint Cardio system. The wireless Checkpoint Cardio system is able to
monitor continuously heart rate, respiratory rate, axillary temperature,
non-invasive blood pressure and oxygen saturation.

A provocation test can be performed in 2 ways: 1. placebo-controlled (i.e. with
placebos) or 2. open challenge (i.e. without placebos). In patients in whom
placebo-controlled challenge is performed, the placebo day (no allergic
reaction expected) will be compared with the verum day, and the measurements
before the food challenge (i.e. baseline) will be compared with the
measurements during and after the challenge. In patients with an open food
challenge the measurements before the food challenge (i.e. baseline) will be
compared with those during the food challenge. We will also take into account
the severity of the allergic reaction when it occurs.

No immediate benefits are expected for the subjects. The patients will undergo
a provocation test in the context of standard care. The attachment of sensors
in the ear and on the body may be unpleasant but not harmful. There are no
risks attached to the use of the sensors. Sensors detecting early warning
signals could prevent serious reactions during diagnostic procedures.