Allergy and intolerance
IgE antilichamen Alternaria
Antibodies against the mold Alternaria; shows whether the immune system is sensitive to this mold, not whether it bothers you.
Everything about this testWhat it measures
Alternaria alternata is a mold that mainly grows outdoors, on plants, grain, grass and in the soil. The spores are mainly in the air in summer and early autumn, most of all on warm, dry and windy days; indoors, the mold can grow in damp places. This test measures the amount of IgE antibodies against Alternaria alternata in the blood, in kU/l. Other molds, such as Cladosporium and Aspergillus, are not measured with this test.
- Sensitization to the mold Alternaria: the body has made IgE antibodies against it
- Support in working out a suspected mold allergy, together with the history of the symptoms, especially with asthma or shortness of breath in summer and early autumn
High
A value above the cut-off means that you have IgE antibodies against Alternaria: sensitization. That is not the same as an allergy. In people with nose or eye symptoms, coughing or shortness of breath in summer and early autumn, or when working with plants, grain or compost, a positive result may fit an allergy to this mold. In research, sensitization to Alternaria is linked to asthma, in children sometimes to asthma that is harder to bring under control. In people without such symptoms, a positive result only means that the antibodies are there; no treatment follows.
Low
A value below the cut-off means that no IgE antibodies against this allergen were found. An IgE-mediated allergy to this allergen is then much less likely, although it is not completely ruled out. Symptoms can also come from another allergen that was not tested, or have a non-allergic cause.
If your result is abnormal
The GP mainly looks at the history: when and where the symptoms occur, and whether there is asthma. With a positive result and matching symptoms, the advice mainly concerns limiting contact with molds, for example by tackling damp and mold patches in the home and ventilating well. If needed, medication for the nose, eyes or airways follows, and with symptoms that are not brought under control with this, a referral to an ENT specialist, lung specialist or allergist may follow.
Reliability
A positive IgE result shows sensitization, not allergy: it only says that there are antibodies, not that you get symptoms from them. The Dutch medical specialists' guideline (FMS) on upper airway allergy says this literally and recommends choosing a test for single allergens based on the history of the symptoms; for food allergy, the FMS guideline on food challenge testing calls the history of the symptoms the cornerstone of diagnosis and a food challenge in hospital the gold standard. The result therefore only means something if it fits when, where and after contact with what you get symptoms. A positive result without symptoms is not treated.
Limitations
- Sensitization without symptoms is common; the result can only be interpreted together with the history of the symptoms.
- Related allergens can recognize each other's antibodies (cross-reaction), for example pollen and nuts or fruit; a positive result then does not mean that this particular allergen causes the symptoms.
- The test measures all proteins from the allergen source together; testing for individual proteins (components) can say more in case of doubt.
- Laboratories use different measurement methods and cut-off values; results from different labs cannot be compared one to one.
How common is this
Molds are, besides pollen, house dust mite and pets, a well-known cause of allergic nasal symptoms. Mold allergy is less common than allergy to pollen or house dust mite; Alternaria is considered one of the most important molds in respiratory allergy, especially in children. Sensitization is more common than the allergy itself.
Who is this useful for
Useful with nose or eye symptoms, coughing or shortness of breath that fit molds: outdoors in summer and early autumn, when working with plants, grain, hay or compost, or in a home with damp and mold patches. Also with asthma where the symptoms get worse in those months. In people without such symptoms, the test adds nothing: sensitization without symptoms is not a disease and is not treated.
Sources
- NVKC, allesovertesten.nl: Allergie (RAST)
- FMS Richtlijnendatabase: Allergie van de bovenste luchtwegen, module Aanvullende diagnostiek
- FMS Richtlijnendatabase: Voedselprovocatie, module Plaatsbepaling diagnostiek voedselallergie
- Thuisarts.nl: Ik heb allergie
- Thuisarts.nl: Ik heb lange tijd of vaak neusklachten door een allergie
- Klain A, Giovannini M, Arasi S, et al. Alternaria allergy and asthma in children. Medicina (Kaunas) 2025;61:1639
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