Allergy and intolerance
IgE totaal
The total amount of IgE in your blood; a general measure that on its own does not show what you are allergic to.
Everything about this testWhat it measures
This test measures how much immunoglobulin E (IgE) there is in total in your blood. IgE is the type of antibody that, in an allergic reaction, prompts mast cells to release histamine; it also helps defend against parasites such as worms. Unlike specific IgE, this test does not look at which substance the antibodies are directed against, only at the total amount. The reference values depend on age and on the measuring method, so each laboratory has its own limits.
- A sign that the immune system tends to react allergically in general, for example with hay fever, asthma or eczema
- A sign of a parasitic infection, for example a worm infection
- Rarely: a strongly raised value in the rare hyper-IgE syndrome or in a bone marrow disease
High
A raised total IgE fits an allergic tendency, but does not say what you are allergic to. The value is often higher in people with eczema, asthma or hay fever and in a parasitic infection. According to the Dutch Society for Clinical Chemistry (NVKC), the symptoms may also not fit the raised result at all; the diagnosis of allergy is made based on the symptoms, possibly supplemented with IgE results. Rarely, a strongly raised value goes with hyper-IgE syndrome or a bone marrow disease; an allergy must then first have been ruled out.
Low
A normal or low total IgE does not rule out an allergy. People with, for example, a peanut or grass pollen allergy can have a normal total value, because the amount of antibodies against that one allergen is small compared with the total. A low value on its own has no meaning and needs no further testing.
If your result is abnormal
With symptoms that fit an allergy, the GP looks at what triggers the symptoms and, if needed, has specific IgE measured or refers you to an allergist. With a strongly raised value without allergic symptoms, the GP may look for another cause, for example a parasitic infection.
Reliability
Total IgE is a general measure and not an allergy test: at most it shows sensitization in general and never an allergy. The Superior Health Council (Hoge Gezondheidsraad) states that total IgE tests on their own give no relevant information when looking into food hypersensitivity; specific IgE tests only mean something together with a clinical assessment. A normal value does not rule out an allergy and a raised value does not prove one. When looking into symptoms, the story of what triggers your symptoms is more important than this result.
Limitations
- The reference values depend on age and differ by measuring method and by laboratory.
- A parasitic infection, smoking and eczema can raise the value without an allergy being involved.
- The value says nothing about which allergen causes symptoms; that requires specific IgE or a skin prick test.
- IgG tests on foods measure something completely different and, according to the Superior Health Council (Hoge Gezondheidsraad), have no place in diagnosing food hypersensitivity.
How common is this
Allergic conditions such as hay fever, asthma and atopic eczema are common in the Netherlands; some of the people with these conditions have a raised total IgE. An exact Dutch figure for how often a raised total IgE occurs is not available. Hyper-IgE syndrome is very rare.
Who is this useful for
The test is used in hospital for specific questions, for example when a parasitic infection or a rare immune disorder is suspected, and sometimes as a background value when assessing other IgE results. As a stand-alone test to see whether you are allergic, total IgE adds little: the result does not point to an allergen and rules nothing out. With symptoms that look like an allergy, the conversation about what triggers the symptoms is the first step.
Downsides and risks
- A raised value without symptoms can cause unnecessary worry and lead to further testing that yields nothing.
- A normal value can give false reassurance: it does not rule out an allergy.
Sources
Always discuss an abnormal result with your GP. If a result is strongly abnormal, we try to reach you as soon as possible. Read your result yourself as well and contact your GP if in doubt. A test does not make a diagnosis. Read more about risks and results