Table 1.
Overview of selected studies on small fiber pathology in fibromyalgia syndrome.
| Author, y | Reference | IENFD reduced (leg) | QST indicates small fiber dysfunction | EP indicates dysfunction of small fibers or their ascending tracts | CCM pathological | MN pathological | Other tests/comments |
|---|---|---|---|---|---|---|---|
| Üçeyler et al. 2013 | 57 | Yes | Yes | Yes | — | — | |
| Oaklander et al. 2013 | 46 | Yes | — | — | — | — | |
| Albrecht et al. 2013 | 1 | — | — | — | — | — | Excessive peptidergic innervation in dermal arteriovenous shunts |
| de Tommaso et al. 2014 | 12 | Yes | — | Yes | — | — | |
| Caro and Winter 2014 | 9 | Yes | — | — | — | — | |
| Giannoccaro et al. 2014 | 25 | Yes | — | — | — | — | |
| Kosmidis et al. 2014 | 37 | Yes | — | — | — | — | |
| Serra et al. 2014 | 52 | — | — | — | — | Yes | |
| Doppler et al. 2015 | 15 | Yes | Yes | — | — | — | Electron microscopy reveals reduced axonal diameters |
| Evdokimov et al. 2019 | 19 | Yes | Yes | Yes | Yes | Yes | |
| Evdokimov et al. 2020 | 18 | — | — | — | — | — | Dermal blood vessel innervation reduced |
| Fasolino et al. 2020 | 22 | Yes* | Yes* | Yes* | — | — | SFP not related to somatosensory function |
| Vecchio et al. 2020 | 59 | Yes | — | No | — | — | LEPs indicative of central impairment |
| Van Assche et al. 2020 | 58 | — | — | No | — | — | LEPs not pathologic in FMS |
| Pickering et al. 2020 | 47 | — | Yes | — | — | — | Sudomotor function impaired |
| Leone et al. 2023 | 40 | Yes | Yes | — | — | — | |
| Quitadamo et al. 2023 | 50 | Yes | — | — | — | — | IENFD not changed over time (18 mo) |
| Falco et al. 2024 | 21 | Yes | — | — | — | — | Innervation of piloerector muscles and sweat glands reduced |
CCM, corneal confocal microscopy; EPs, evoked potentials; FMS, fibromyalgia syndrome; IENFD, intraepidermal nerve fiber density; LEPs, laser-evoked potentials; MN, microneurography; QST, quantitative sensory testing; SFP, small fiber pathology; —, not performed.
*
Partially.