Peripheral Nerve Hyperexcitability Syndromes (PNH)
Peripheral Nerve Hyperexcitability (PNH) syndromes encompass a spectrum of disorders, including Isaacs syndrome, neuromyotonia, and cramp-fasciculation syndrome, characterized by abnormal, continuous muscle fiber activity due to primary neural dysfunction. These syndromes share overlapping clinical and electrophysiological features.
Isaacs Syndrome: A Key PNH Syndrome
Isaacs syndrome is a rare disorder of continuous motor unit activity that primarily arises due to an acquired channelopathy. The condition is strongly associated with antibodies against voltage-gated potassium channels (VGKC).