Myasthenia Gravis (MG)/Lambert-Eaton Syndrome (LES) Evaluation
Method Description Describes how the test is performed and provides a method-specific reference
Calcium channel binding antibodies (IgG and IgM) are measured quantitatively by immunoprecipitation assays. Selective high-affinity ligands labeled with (125)I are complexed with cation channel proteins detergent-solubilized from membranes of pig cerebral cortical synaptic membranes; omega conopeptide GVIA identifies neuronal N-type Ca(++) channels; omega conopeptide MVIIC identifies neuronal P/Q-type Ca(++) channels; (125)I -alpha-bungarotoxin identifies muscle AChR solubilized from a mixture of innervated and denervated human skeletal muscle. AChR modulating antibody is detected in a bioassay: following 14 hours of incubation with patient's serum, viable, noninnervated, monolayer cultures of human muscle cells are probed with (125)I-bungarotoxin to quantitate percent loss of surface AChR. Striational antibodies (IgG, IgM, and IgA) are detected by EIA using as antigen a mixture of sarcomeric proteins extracted from healthy adult rat skeletal muscle.(Griesmann GE, Kryzer TJ, Lennon VA: Autoantibody profiles of myasthenia gravis and Lambert-Eaton myasthenic syndrome. In Manual of Clinical and Laboratory Immunology. Sixth edition. Edited by NR Rose, RG Hamilton, B Detrick. Washington, DC, ASM Press, 2002, pp 1005-1012)
Day(s) and Time(s) Test Performed Outlines the days and times the test is performed. This field reflects the day and time the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time required before the test is performed. Some tests are listed as continuously performed, which means assays are performed several times during the day.
P/Q-type calcium channel antibody: Monday, Wednesday, Friday; 6 a.m.
N-type calcium channel antibody: Monday, Wednesday, Friday; 6 a.m..
ACh receptor (muscle) binding antibody: Monday through Thursday; 6 p.m., Saturday; 10 a.m.
ACh receptor (muscle) modulating antibodies: Monday through Thursday; 11 a.m.
Striational (striated muscle) antibodies: Monday through Thursday, Sunday; 10:30 p.m.
CRMP-5-IgG Western blot: Monday through Friday; 6 a.m.
AChR ganglionic neuronal antibody: Tuesday, Thursday, Sunday; 6 a.m.
Analytic Time Defines the amount of time it takes the laboratory to setup and perform the test. This is defined in number of days. The shortest interval of time expressed is "same day/1 day," which means the results may be available the same day that the sample is received in the testing laboratory. One day means results are available 1 day after the sample is received in the laboratory.
Maximum Laboratory Time Defines the maximum time from specimen receipt at Mayo Medical Laboratories until the release of the test result
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 The location of the laboratory that performs the test