Small fibre neuropathy

Abstract

In the last 5 years, the chapter of SFN has been widened by new clinical and genetics descriptions leading to a more comprehensive approach to patients in clinical practice and research.

Small‐fiber neuropathy: Expanding the clinical pain universe

“…Definite : Presence of length‐dependent symptoms, clinical signs of small‐fiber damage, normal sural NCS, and reduced IENFD at the ankle and/or abnormal thermal thresholds …”

“…Patients with predominant features of SFN and clinical and NCS findings of large sensory fiber dysfunction should be considered to have a mixed (small and large fiber) sensory neuropathy, also described as predominant SFN. A correct classification of SFN is of importance, as it impacts the workup for an underlying condition and the design of clinical trials …”

“…It has been suggested to add QSART as one of the core diagnostic tests, requiring abnormality on two measures for a diagnosis of SFN (clinical findings, QST, QSART and skin biopsy). Although QSART can be of value in the diagnosis of SFN, normative data are needed to determine its usefulness for clinical practice …”

“…SFN is associated with multiple diseases which can be categorized as metabolic, immune‐mediated, and infectious diseases, exposure to drugs and toxins, and genetic causes . In a large cohort of 921 patients, 75% of them did not have a known preselected comorbidity before the diagnostic workup.…”

“…Definite: Presence of length-dependent symptoms, clinical signs of small-fiber damage, normal sural NCS, and reduced IENFD at the ankle and/or abnormal thermal thresholds. 1,24,25 However, this definition only includes length-dependent symptoms, whereas the spectrum of clinical signs has widened from the classical length-dependent SFN to include non-length-dependent patterns. [2][3][4][5] Furthermore, according to this definition, the diagnosis SFN should be considered only in patients with pure or isolated impairment of the Aδ-and C-fibers.…”