Non-length-dependent small fibre neuropathy. Confocal microscopy study of the corneal innervation.
BACKGROUND
It has been recently observed that small fibre neuropathy (SFN) may present as distal symmetrical polyneuropathy and with atypical non-length-dependent pattern.


OBJECTIVE
To describe a small series of patients with non-length-dependent SFN, investigating corneal innervation with corneal confocal microscopy (CCM).


METHODS
Evaluation of the corneal nerve fibre density using CCM in six women with non-length-dependent SFN. The patients were characterised by sensory disturbance involving proximal regions of the limbs, face and trunks, and the diagnosis was confirmed by the findings of decreased intraepidermal nerve fibre density on skin biopsy.


RESULTS
Six women, aged 35-64, had non-length-dependent SFN, related to Crohn disease, impaired glucose tolerance and Sjögren's syndrome, or idiopathic (three cases). In all patients, CCM demonstrated decreased corneal nerve fibre density (12.5-23.4/mm(2); normal, >30.6/mm(2)).


CONCLUSIONS
Non-length-dependent SFN may represent an intriguing diagnostic problem because of its puzzling presentation and the need for special investigations for its confirmation. In this perspective, CCM may provide a useful, non-invasive tool to complement the diagnostic workup.
Gemignani
F
F
Department of Neurosciences, University of Parma, via Gramsci 14, I-43100 Parma, Italy. franco.gemignani@unipr.it
Ferrari
G
G
Vitetta
F
F
Giovanelli
M
M
Macaluso
C
C
Marbini
A
A
D000328:Adult; D000588:Amines / Q000627:therapeutic use; D000639:Amitriptyline / Q000627:therapeutic use; D000700:Analgesics / Q000627:therapeutic use; D018687:Antidepressive Agents, Second-Generation / Q000627:therapeutic use; D000929:Antidepressive Agents, Tricyclic / Q000627:therapeutic use; D001706:Biopsy; D003315:Cornea / Q000294:innervation* / Q000473:pathology*; D003424:Crohn Disease / Q000150:complications / Q000473:pathology; D003509:Cyclohexanecarboxylic Acids / Q000627:therapeutic use; D000068736:Duloxetine Hydrochloride; D004594:Electrophysiology; D005260:Female; D000077206:Gabapentin; D006801:Humans; D018613:Microscopy, Confocal / Q000379:methods*; D008875:Middle Aged; D009411:Nerve Endings / Q000473:pathology / Q000648:ultrastructure; D009412:Nerve Fibers / Q000473:pathology*; D010523:Peripheral Nervous System Diseases / Q000188:drug therapy / Q000473:pathology*; D012678:Sensation Disorders / Q000150:complications / Q000473:pathology; D012859:Sjogren's Syndrome / Q000150:complications / Q000473:pathology; D012867:Skin / Q000294:innervation / Q000473:pathology; D013876:Thiophenes / Q000627:therapeutic use; D014276:Trigeminal Nerve / Q000473:pathology / Q000648:ultrastructure; D005680:gamma-Aminobutyric Acid / Q000627:therapeutic use
D000588:Amines; D000700:Analgesics; D018687:Antidepressive Agents, Second-Generation; D000929:Antidepressive Agents, Tricyclic; D003509:Cyclohexanecarboxylic Acids; D013876:Thiophenes; D000639:Amitriptyline; D005680:gamma-Aminobutyric Acid; D000077206:Gabapentin; D000068736:Duloxetine Hydrochloride