LOINC Code 18424-2: Phthalic anhydride IgM Qn (S)

What is this code?

LOINC codes identify tests, measurements, observations, survey items, and clinical questions in a standardized way. It is associated with the component Phthalic anhydride Ab.IgM. It is commonly used with the system or sample type Ser.

When is it used?

• Used in lab systems, EHRs, and clinical data exchange.
• May identify a test, observation, survey item, or clinical document request rather than a diagnosis.
• Status: ACTIVE
• Order vs observation: Both

What it does not mean

• The code identifies the observation or test, not the actual result.

Key facts

• Phthalic anhydride IgM Ab [Units/volume] in Serum
• Phthalic anhydride Ab.IgM
• 1,2-benzenedicarboxylic acid anhydride; 1,2-benzenedicarboxylic anhydride; 1,3-dioxophthalan; 1,3-isobenzofurandione; 1,3-phthalandione; ABS; Aby; Allergen; Allergens; ALLERGY TESTING; Anhydrid; Antby; Anti; Antibodies; Antibody; Arbitrary concentration; Autoantibodies; Autoantibody; Immune globulin M; Immunoglobulin M; k79; PAN; Phthalandione; Point in time; QNT; Quan; Quant; Quantitative; Random; Serum; SR

Where you may see this code

You may see this code in lab systems, lab reports, EHR exports, interoperability feeds, or other structured clinical data exchanges.

Common synonyms

Frequently asked questions