Voltage-Gated Calcium Channel (VGCC) Antibody details

Voltage-gated calcium channels are proteins on nerve endings that help release the chemical signals that make muscles contract. This test measures autoantibodies against the P/Q type of these channels. It is mainly used when someone has muscle weakness, fatigue or other symptoms that suggest Lambert-Eaton myasthenic syndrome, an autoimmune condition that is sometimes linked to an underlying cancer, especially small cell lung cancer. A positive result supports this type of autoimmune process but does not diagnose a condition on its own. Low levels can occasionally be found without the condition, so results are interpreted with nerve studies, symptoms and further testing.