That is simply incorrect. Peripheral Neuropathy (PN) by definition is a disease of the periphery, i.e. the hands and feet. Small Fiber Neuropathy (SFN), in which only the small sensory cutaneous nerves are affected, can affect the entire body (and bodily functions one would not readily associate with neuropathy). Therefore, one could simply have PN, or conversely, SFN that is only affecting the periphery (where symptoms often begin). However without a biopsy, one cannot be sure which disease they have. If the symptoms remain in the hands and feet, a lack of confirmation is not a problem, as one would most likely treat and deal with the pain in the same manner. If the problems progress beyond the periphery, one is in a more difficult situation. Many of the full body debilitating symptoms (detailed below) of SFN mirror those of other serious diseases and without a biopsy, one could only assume they were a product of the SFN. The state of not knowing can create extreme anxiety. I have a confirmed case of SFN and still get extreme states of anxiety when a new pain or condition arises. However, even in many medical journals, the medical community often refers to the disease as one of the hands and feet, regardless if this is merely out ignorance or hubris. When Swedish did my biopsy, they sent it to a neuropathology company called Therapath for analysis. Their information on SFN (copied below) best describes the disease. One cannot read the following and think PN and SFN are even close to the same disease…

Therapath: Symptoms of sensory small fiber neuropathy include numbness, hypersensitivity, and spontaneous painful or annoying sensations called paresthesias. The latter can present as tingling, burning, freezing, stinging, stabbing, itching, squeezing, tearing, buzzing, aching, or electric sensations that fluctuate in severity. These sensations can occur anywhere in the body, including the feet, arms, legs, torso, scalp, face, or even the mouth.

Symptoms of autonomic small fiber neuropathy include abnormal sweating or temperature regulation, lightheadedness or fainting when standing up from hypotension or tachycardia, gastroparesis with bloating and constipation or diarrhea, incomplete bladder emptying or difficulty initiating a stream, sexual dysfunction from hypo or hypersensitivity, dryness and thinning of the skin, hair loss in the legs, and ridged or brittle nails.

Patients with rheumatological disorders can present with a variety of syndromes that can result from Small Fiber Neuropathy (SFN). These include musculoskeletal pain, muscle cramps, fasciculations, widespread unexplained pain, reflex sympathetic dystrophy/complex regional pain syndrome, burning paresthesias, and autonomic instability including orthostatic hypotension, postural tachycardia, or gastrointestinal dysmotility.