LOINC Code 94450-4: HLA-A & B & C (class I) Ab.IgG intermediate risk FC Nom

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 HLA-A & B & C (class I) Ab.IgG intermediate risk. It is commonly used with the system or sample type Ser/Plas.

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: Observation
• Method: Flow cytometry

What it does not mean

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

Key facts

• HLA-A and B and C (class I) IgG intermediate risk [Identifier] in Serum or Plasma by Flow cytometry (FC)
• HLA-A & B & C (class I) Ab.IgG intermediate risk
• Laboratories that perform HLA antibody testing often report the specific antibodies found in categories based on the "amount" of each antibody found (called mean fluorescent intensity, MFI, for the common Luminex bead method). Theoretically, the antibodies present in higher concentrations, which are more likely to react with donor antigens, will have higher MFI values. Since risk stratification based on MFI range is not standardized and the exact cutoffs vary from lab to lab, this term is intended to report those HLA antibodies found in an intermediate risk stratification of MFI values (For one lab this was 4999 > MFI > 2000, but some laboratories use other values).
• A,B; Dynamic; FC; Genetics; Heredity; Heritable; HLA ANTIGEN; HLA class I; HLA class I Ab.IgG med risk; HLA-A+B; HLA-A+B+C; HLA-A+B+C (class I); Human Leukocyte Antigen; Identity or presence; Immune globulin G; Immunoglobulin G; Inherited; Nominal; Pl; Plasma; Plsm; Point in time; Random; SerP; SerPl; SerPlas; Serum; Serum or plasma; 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