Active not recruitingNAINTERVENTIONAL

Investigation of the Frequency of Hereditary Hyper Alpha-tryptasemia in Patients With Elevated Basal Tryptasemia

This study is looking into why some people have higher than normal levels of a substance called tryptase in their blood. Tryptase levels can be high for various reasons, and researchers want to find out if it's due to a specific inherited condition known as hereditary hyper-alpha-tryptasemia. This condition means a person has extra copies of a gene that makes alpha-tryptase. By understanding this, doctors hope to improve how they look after patients who have allergic reactions and also have consistently high tryptase levels. People who agree to join the study will have a blood test to check for this genetic condition, and receive their results at a follow-up appointment.

At a glance

Status

Active not recruiting

Phase

Sponsor

Centre Hospitalier Universitaire de Nice

Enrolment target

100

Start

05 Dec 2023

Estimated completion

01 Mar 2027

Allergic Bronchiolitis

What is this study about?

Doctors at a specialist allergy department are trying to understand more about why some people have higher levels of a substance called tryptase in their blood. Tryptase is a chemical that's released in your body, especially during allergic reactions. Sometimes, a person might have high tryptase levels even when they're not having an allergic reaction; this is called 'elevated basal tryptasemia'.

The study aims to figure out how many of these people with consistently high tryptase levels actually have a specific genetic condition. This condition is called 'hereditary hyper-alpha-tryptasemia', which simply means it's passed down in families and causes a person to naturally produce more alpha-tryptase.

Finding out if high tryptase is due to this inherited condition is important. It will help doctors understand more about these patients and could lead to better ways to manage their care, especially for those who experience severe allergic reactions.

Key takeaways

The study investigates why some people have high blood tryptase levels.
It checks for a genetic condition called hereditary alpha-tryptasemia.
Understanding this could lead to better management for allergy patients.
Participation involves a blood test and a follow-up appointment.
This study is for adults over 18 who have had allergy tests and tryptase measurements.
Knowing your genetic status might help explain your tryptase levels.

Who may be eligible?

This study is looking for adults who have visited the pneumo-allergy department at CHU de Nice since January 2014 for allergy tests.

You might be able to join if you have had your 'basal tryptase' levels checked at least once, following standard medical advice. You must also be over 18 years old and willing to give your written permission to take part.

You won't be able to join if your high tryptase level was only measured during an anaphylactic (very severe allergic) reaction and hasn't been confirmed as high when you're well. Also, if you already have a diagnosed condition called 'systemic mastocytosis', you won't be eligible.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

Are you 18 years old or older?
Have you visited the pneumo-allergy department at CHU de Nice for allergy tests since January 2014?
Have you had your regular (basal) blood tryptase level checked at least once?
Do you NOT have a diagnosis of systemic mastocytosis?
Was your high tryptase level confirmed when you were well, not just during a severe allergic reaction?

Answer every question to see your result.

What does participation involve?

If you decide to take part, your participation will mainly involve one visit to the clinic for a blood test. During this visit, a small sample of your blood will be taken. A few weeks later, you will have a medical appointment at the clinic where your doctor will explain the results of your blood test. There is no medication involved in this study, and the overall commitment is minimal, focused on these two appointments.

Potential risks and benefits

Taking part in this study could potentially help advance our understanding of allergic conditions and high tryptase levels, which might lead to better care for patients in the future. For you personally, it could provide information about whether you have an inherited condition related to tryptase levels. The risks are very low, primarily those associated with a standard blood test, such as slight bruising or discomfort at the injection site. You have the right to withdraw from the study at any time without giving a reason, and this will not affect your medical care.

Locations (1)

CHU de Nice - Hôpital de Pasteur
Verified postcode
Nice, France

Common questions

What is tryptase?

Tryptase is a natural chemical in your body, often released during allergic reactions. Doctors sometimes measure its level in your blood.

What does 'hereditary hyper-alpha-tryptasemia' mean?

It's a genetic condition, passed down through families, where your body naturally makes more of a specific type of tryptase called alpha-tryptase.

Why are doctors studying this?

They want to understand if this genetic condition is why some people have consistently high tryptase levels, which could help manage their allergies better.

What do I have to do if I join?

You'll have a blood test at the clinic, and then a follow-up appointment a few weeks later to get your results.

Will this help my allergies directly?

The study aims to improve general understanding which could benefit future patient care. For you, it might explain why your tryptase levels are high.