Small Fiber Neuropathy: Clinicopathological Correlations.

Area of Science:

• Neurology
• Pathology

Background:

• Small fiber neuropathy (SFN) results from damage to thin peripheral nerve fibers.
• It is associated with various conditions like diabetes, infections, autoimmune disorders, and genetic factors.

Purpose of the Study:

• To analyze the causes, clinical features, and pathological findings in skin biopsy-proven small fiber neuropathy cases.
• To investigate gender differences and the impact of diabetes on SFN.

Main Methods:

• Retrospective analysis of 85 skin biopsy-proven small fiber neuropathy cases.
• Categorization of cases into idiopathic and secondary types based on underlying causes.
• Evaluation of intraepidermal fiber density and correlation with clinical measures.

Main Results:

• 48% of cases were idiopathic; common secondary causes included hypothyroidism, diabetes mellitus, cryoglobulinemia, and Sjögren's disease.
• 68% of patients were female; secondary SFN onset was 8 years later than idiopathic.
• Severe small fiber pathology was noted in men and diabetic patients; weak correlations were found between patient-reported measures and pathology.

Conclusions:

• Small fiber damage significantly contributes to neuropathic symptoms across various conditions.
• Gender differences exist in clinical presentation and pathological alterations.
• Diabetes mellitus is a significant cause of severe small fiber pathology.