Test Id : CCPQ
P/Q-Type Calcium Channel Antibody, Serum
Useful For
Suggests clinical disorders or settings where the test may be helpful
Confirming a diagnosis of Lambert-Eaton syndrome
Implicating autoimmunity as a disease-causing mechanism in patients with complex neurologic presentations, particularly in those with a history of cancer
Implicating autoimmunity as the basis of limbic encephalitis, cerebellar ataxia, myelopathy, peripheral neuropathy, or autonomic neuropathy
This test is not useful as a general screening test for cancer.
Method Name
A short description of the method used to perform the test
Only orderable as part of a profile. For more information see:
MDS2 / Movement Disorder, Autoimmune/Paraneoplastic Evaluation, Serum
MGLE / Myasthenia Gravis/Lambert-Eaton Myasthenic Syndrome Evaluation, Serum
PNEFS / Neuroimmunology Antibody Follow-Up, Serum
Radioimmunoassay (RIA)
NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.
Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test
Aliases
Lists additional common names for a test, as an aid in searching
Calcium Channel Blockers
Conotoxin (Receptor) Antibodies
Lambert-Eaton Myasthenic Syndrome Ab
LEMS Antibodies
Motor Nerve Terminal Antibodies
P/Q Type Calcium Channel Antibody, Serum
P/Q-Type Calcium Channel
Paraneoplastic Autoantibody Comprehensive Panel, Serum
Paraneoplastic Autoantibody Lung/Thymoma Panel, Serum
Voltage-Gated Calcium Channel Ab
Specimen Type
Describes the specimen type validated for testing
Serum
Ordering Guidance
The profile test should not be requested in patients who have recently received radioisotopes, therapeutically or diagnostically, because of potential assay interference. The specific waiting period before specimen collection will depend on the isotope administered, the dose given, and the clearance rate in the individual patient. Specimens will be screened for radioactivity prior to analysis. Radioactive samples received in the laboratory will be held 1 week and assayed if sufficiently decayed or canceled if radioactivity remains.
Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing
Only orderable as part of a profile. For more information see:
MDS2 / Movement Disorder, Autoimmune/Paraneoplastic Evaluation, Serum
MGLE / Myasthenia Gravis/Lambert-Eaton Myasthenic Syndrome Evaluation, Serum
PNEFS / Neuroimmunology Antibody Follow-Up, Serum
Specimen Minimum Volume
Defines the amount of sample necessary to provide a clinically relevant result as determined by the testing laboratory. The minimum volume is sufficient for one attempt at testing.
0.5 mL
Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected
| Gross hemolysis | Reject |
| Gross lipemia | Reject |
| Gross icterus | Reject |
Specimen Stability Information
Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Serum | Refrigerated (preferred) | 28 days | |
| Ambient | 72 hours | ||
| Frozen | 28 days |
Useful For
Suggests clinical disorders or settings where the test may be helpful
Confirming a diagnosis of Lambert-Eaton syndrome
Implicating autoimmunity as a disease-causing mechanism in patients with complex neurologic presentations, particularly in those with a history of cancer
Implicating autoimmunity as the basis of limbic encephalitis, cerebellar ataxia, myelopathy, peripheral neuropathy, or autonomic neuropathy
This test is not useful as a general screening test for cancer.
Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
This test is not offered as a standalone test but is included in the following test procedures as an aid for diagnosis of neurological autoimmunity, usually in a paraneoplastic context.
-MDS2 / Movement Disorder, Autoimmune/Paraneoplastic Evaluation, Serum
-MGLE / Myasthenia Gravis/Lambert-Eaton Myasthenic Syndrome Evaluation, Serum
P/Q-type calcium channels regulate neurotransmitter release at motor nerve terminals and are involved in central neurotransmission.
A snail venom toxin, omega conopeptide MVIIC, is a specific high-affinity antagonist for P/Q-type channels.
Autoantibodies directed against extracellular epitopes of P/Q-type calcium channels are implicated as the effectors of the Lambert-Eaton myasthenic syndrome (LES).
These antibodies generally reflect an immune response against cancer.
P/Q-type calcium channel binding antibodies are found in 95% of nonimmunosuppressed patients with LES (100% of those with cancer) and in 20% of patients who have encephalomyeloneuropathies related to carcinoma of lung, breast, or ovary.
Reference Values
Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
Only orderable as part of a profile. For more information see:
MDS2 / Movement Disorder, Autoimmune/Paraneoplastic Evaluation, Serum
MGLE / Myasthenia Gravis/Lambert-Eaton Myasthenic Syndrome Evaluation, Serum
PNEFS / Neuroimmunology Antibody Follow-Up, Serum
< or =0.02 nmol/L
Interpretation
Provides information to assist in interpretation of the test results
Values greater than 0.02 nmol/L are consistent with neurologic autoimmunity and suggest a paraneoplastic basis.
Values in nonimmunosuppressed patients with Lambert-Eaton syndrome are usually greater than 0.1 nmol/L.
Cautions
Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
High-dose intravenous IgG therapy may cause false-lowering of (or negative) values.
Plasma specimens can yield false-positive results.
The influence of myeloma M proteins is uncertain.
Clinical Reference
Recommendations for in-depth reading of a clinical nature
1. Lennon VA, Kryzer TJ, Griesmann GE, et al. Calcium-channel antibodies in the Lambert-Eaton myasthenic syndrome and other paraneoplastic syndromes. N Engl J Med. 1995;332(22):1467-1474
2. Lennon VA. Serological profile of myasthenia gravis and distinction from the lambert-eaton myasthenic syndrome. Neurology. 1997;48(Suppl 5):S23-S27
3. Zalewski NL, Lennon VA, Lachance DH, Klein CJ, Pittock SJ, Mckeon A. P/Q- and N-type calcium-channel antibodies: Oncological, neurological, and serological accompaniments. Muscle Nerve. 2016;54(2):220-227. doi:10.1002/mus.25027
Method Description
Describes how the test is performed and provides a method-specific reference
High voltage-activated calcium channels of P/Q-type (ie, high affinity receptors for omega-peptide MVIIC) are solubilized from porcine cerebral cortical membranes in detergent and are complexed with (125)I-labeled omega-conopeptide-MVIIC. After incubating patient sample with labeled receptors, anti-human IgG is added to form an immunoprecipitate. The amount of (125)I-labeled receptors in the immunoprecipitate is measured using a gamma-counter. The amount of gamma emission in the precipitate is proportional to the amount of CCPQ-IgG in the sample. Results are reported as units of precipitated antigen (nMol) per L of patient sample.(Griesmann GE, Kryzer, TJ, Lennon VA. Autoantibody profiles of myasthenia gravis and Lambert-Eaton myasthenic syndrome. In: Rose NR, Hamilton RG, Detrick B, eds. Manual of Clinical and Laboratory Immunology. 6th ed. ASM Press; 2002:1005-1012; Jones AL, Flanagan EP, Pittock SJ, et al. Responses to and outcomes of treatment of autoimmune cerebellar ataxia in adults. JAMA Neurol. 2015;72[11]:1304-1312 doi:10.1001/jamaneurol.2015.2378)
PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information
Day(s) Performed
Outlines the days the test is performed. This field reflects the day that the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time before the test is performed. Some tests are listed as continuously performed, which means that assays are performed multiple times during the day.
Monday through Sunday
Report Available
The interval of time (receipt of sample at Mayo Clinic Laboratories to results available) taking into account standard setup days and weekends. The first day is the time that it typically takes for a result to be available. The last day is the time it might take, accounting for any necessary repeated testing.
Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
Performing Laboratory Location
Indicates the location of the laboratory that performs the test
Fees :
Several factors determine the fee charged to perform a test. Contact your U.S. or International Regional Manager for information about establishing a fee schedule or to learn more about resources to optimize test selection.
- Authorized users can sign in to Test Prices for detailed fee information.
- Clients without access to Test Prices can contact Customer Service 24 hours a day, seven days a week.
- Prospective clients should contact their account representative. For assistance, contact Customer Service.
Test Classification
Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR) product.
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.
CPT Code Information
Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Clinic Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.
CPT codes are provided by the performing laboratory.
CPT codes are provided by the performing laboratory.
86596
LOINC® Information
Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the order and results codes of this test. LOINC values are provided by the performing laboratory.
| Test Id | Test Order Name | Order LOINC Value |
|---|---|---|
| CCPQ | P/Q-Type Calcium Channel Ab | 94349-8 |
| Result Id | Test Result Name |
Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
|
|---|---|---|
| 81185 | P/Q-Type Calcium Channel Ab | 94349-8 |