Complement Activity Total, (CH50)

Casandra

Casandra Test Code AR69728Version 1 (DRAFT)

Performing Lab

Lab ARUP LaboratoriesLab Test ID 3002575CPT Code 86162

Complement Activity Total, (CH50)

Also known as: CH50 TOTAL

Clinical Use

Order Test

Use

The Complement Activity Total (CH50) test is used as an initial screening tool for identifying potential deficiencies in the classical complement pathway. A deficiency in the classical pathway can indicate inherited or acquired defects in the complement system, which is crucial for immune response regulation. CH50 testing can also be used to monitor therapeutic responses to complement deficiencies and to evaluate the extent of the body's classical pathway activity in various disease states like systemic lupus erythematosus and immune complex diseases.

Special Instructions

Not provided.

Limitations

This test cannot distinguish between different types of complement deficiencies or dysfunctions within the classical pathway. Furthermore, it may not adequately reflect complement activity under conditions where complement components are excessively consumed or degraded. Repeated testing may be required to confirm deficiencies, especially when low results do not match the clinical picture of the patient. Complement Activity Total (CH50) does not assess the alternate or lectin pathways, and anomalies in these pathways will not be detected.

Test Details

New York Approved

Methodology

Immunoassay (Multiplex Protein Panel)

Biomarkers

Complement Components

Protein

Total Complement Activity

Concentration / Level • Quantitative (Continuous) (e.g., copies/mL, % expression)

LOINC Codes

Order Codes

4532-8

Result Turnaround Time

1-2 days

Specimen

Serum

Volume

1 mL

Minimum Volume

0.5 mL

Container

ARUP Standard Transport Tube

Collection Instructions

Allow specimen to clot for one hour at room temperature. Separate serum from cells ASAP or within 2 hours of collection. Transfer 1 mL serum to an ARUP Standard Transport Tube.

Storage Instructions

CRITICAL FROZEN

Causes for Rejection

Separator tubes. Specimens left to clot at 2-8 degrees C. Specimens exposed to repeated freeze/thaw cycles. Non-frozen specimens. Grossly hemolyzed or severely lipemic specimens.