Therapath Neuropathology

Pruritis and small fiber neuropathy

April 20, 2018

Chronic pruritis (itching sensation) is associated with a number of medical conditions including several neuropathic illnesses.1 Among those illnesses, small fiber neuropathy (SFN) can cause neuropathic itching. Patients with SFN commonly report pruritis as a leading symptom.2

Pereira et al. report on the diagnostic value of Epidermal Nerve Fiber Density (ENFD) in the management of chronic pruritis. The authors discuss the importance of investigating the underlying cause of the condition:

“An early diagnosis of a neuropathy as the underlying cause of pruritus is essential for the treatment success. Current guidelines recommend the treatment of the underlying cause or, if not possible, the application of topical capsaicin or the systemic use of anticonvulsants or antidepressants.” 3

Other causes of neuropathic pruritis include nerve lesions, radiculopathy, spinal cord damage, and brain lesions.4 Due to the wide range of conditions associated with neuropathic pruritis, ENFD can be a valuable tool in patient evaluation.

Chronic pruritis can lead to skin changes and injuries from scratching. This self injury can be exacerbated in patients with neuropathic sensory loss that allows for scratching without pain.4


References

1.
Twycross R, Greaves M, Handwerker H, et al. Itch: scratching more than the surface. QJM. 2003;96(1):7-26. [PubMed]
2.
Brenaut E, Marcorelles P, Genestet S, Ménard D, Misery L. Pruritus: an underrecognized symptom of small-fiber neuropathies. J Am Acad Dermatol. 2015;72(2):328-332. [PubMed]
3.
Pereira M, Mühl S, Pogatzki-Zahn E, Agelopoulos K, Ständer S. Intraepidermal Nerve Fiber Density: Diagnostic and Therapeutic Relevance in the Management of Chronic Pruritus: a Review. Dermatol Ther (Heidelb). 2016;6(4):509-517. [PMC]
4.
Oaklander A. Neuropathic Itch. Semin Cutan Med Surg. 2011;30(2):87-92. [PMC]