The term "benign" in BFS is much the same as the term "ideopathic" applied to neuropathy. So, BFS is a diagnosis of exclusion. As with neuropathy, you would typically see a neurologist and get MRI's NCV, EMG, blood tests, etc. - mostly the same tests you would get for neuropathy. If you are having ongoing muscle twitches without any evidence of a cause such as ALS, MS, etc. - they would diagnose you with BFS. They also have more severe cases that include muscle cramping (sometimes called "cramp fasciculation syndrome") and the most severe is neuromyotonia where your muscles essentially lock up because the motor neurons keep firing continuously. All of these fall under the umbrella of "peripheral nerve hyperexcitability syndrome". Kind of confusing since several different names are used.