Allergy (respiratory, food, hymenoptera venom) and anaphylaxis: specific IgE and tryptase

Respiratory medicine and allergy · Symptom or situation · updated 2026-10-30

BioMG follows French guidelines. Adapt it to the guidelines and the tests available where you practise.

Frequency: Anaphylaxis: lifetime prevalence of 0.3 to 5.1% depending on definitions and regions ^[1]

Allergic rhinitis, conjunctivitis or asthma (suspected)

Specific IgE: multi-allergen screening test for inhalant allergens (Phadiatop type)
OR single specific IgE to the inhalant allergens indicated by the history (5 at most, to be named on the request form)if neededInstead of the screening test (billing not combinable with it; reimbursement limited to 5 allergens ^[2]), when the history points to one or a few allergens (animal, seasonal pollen, mites): specific IgE are chosen according to the clinical history ^[3].

Detailed explanation and international comparison (in French): read it in English (machine translation)

Associated asthma? For the asthma work-up, including allergic bronchopulmonary aspergillosis, see the page Asthme.

Total IgE to “screen for an allergy”: the fee schedule states that this is not a screening test for allergy and limits its reimbursement to a few situations (polysensitisation, parasitic infections, chronic urticaria, atopic dermatitis, bronchopulmonary aspergillosis, certain immunodeficiencies) ^[2]; insufficient sensitivity and specificity, and it does not identify the allergen ^[3].
“Anti-food” or anti-allergen IgG or IgG4: tests that have not proven their efficacy, which can lead to inappropriate diagnosis and treatment ^[3]; they are markers of tolerance, not of intolerance ^[4].
Multi-allergen identification panels on a single support (biochips, “multitests”) for screening: the fee schedule states that they can in no case be used as screening tests ^[2].
Mites D. pteronyssinus and D. farinae measured together: one is enough ^[4].
Several grasses measured together (timothy and cocksfoot, for example): timothy grass represents the family ^[4].

Specific IgE to the suspected food (single test; 5 food allergens at most, to be named on the request form)
OR food allergen screening test (mixes; infant or imprecise history)if neededInfant or young child whose history does not point to a food: a fx5-type mix (egg white, milk, fish, wheat, peanut, soya) screens for the most frequently implicated allergens ^[4]. Reimbursement limited to 3 mixes, not combinable with single-allergen assays; simultaneous testing with inhalant allergens possible, notably before age 16 ^[2].

Detailed explanation and international comparison (in French): read it in English (machine translation)

Food IgG or IgG4 (“food intolerance tests”): not recommended to demonstrate a food allergy or intolerance; no evidence that eliminating “positive” foods brings a benefit, and an overly restrictive diet exposes to deficiencies ^[4]. Tests without proven efficacy according to the HAS ^[3].
Total IgE: insufficient sensitivity and specificity, do not identify the food ^[3].
Specific IgE for suspected non-IgE-mediated food allergy (delayed reaction, including non-IgE cow's milk protein allergy): the diagnosis rests on a trial elimination followed by reintroduction ^[8].
“Alternative” tests (Vega test, applied kinesiology, hair analysis): not to be used to diagnose food allergy ^[8].

Specific IgE to Hymenoptera venoms (bee, wasp; depending on the insect involved, 5 at most)
Baseline serum tryptase

Detailed explanation and international comparison (in French): read it in English (machine translation)

Venom-specific IgE after a local reaction, even a large one, without general signs: immunotherapy is not indicated for isolated local reactions ^[11], and sensitisation without a history of reaction is common ^[11]; a positive result would therefore have no consequence and would cause needless worry.
Venom-specific IgE in a person who has never reacted to a sting (relative of an allergic person, “as a precaution”): same reason ^[11].

Serum tryptase: between 30 minutes and 2 hours after the onset of symptoms (acceptable up to 4 hours); plain or EDTA tube, time-stamped, with the time of symptom onset

Detailed explanation and international comparison (in French): read it in English (machine translation)

Plasma histamine: not to be done routinely (half-life of 15 to 20 minutes, cumbersome sampling conditions) and no longer reimbursed in France ^[15].
Tryptase sampled within the first 30 minutes: risk of false negative ^[15].

Mild atopic dermatitis: no allergy testing. Suspected food allergy: see the "Allergie alimentaire" tab; moderate or severe atopic dermatitis with suspected food allergy: specialist opinion.

Detailed explanation and international comparison (in French): read it in English (machine translation)

Allergy tests sold online or in shops: no evidence of their value in the management of atopic dermatitis ^[18].

No specific IgE in the community. After drug anaphylaxis: 2 tryptase measurements (see the "Après une anaphylaxie" tab).

Detailed explanation and international comparison (in French): read it in English (machine translation)

Serum specific IgE to diagnose drug allergy outside a specialist department: not to be used ^[19].

Sources (20)