Phenotyping peripheral neuropathies with and without pruritus: a cross-sectional multicenter study

Area of Science:

• Neurology
• Dermatology
• Neuroscience

Background:

• Pruritus (itching) is often overlooked in patients with peripheral neuropathy (PNP).
• PNP affects nerve fibers, potentially leading to sensory disturbances like itching and pain.
• Understanding neuropathic pruritus is crucial for comprehensive patient care.

Purpose of the Study:

• To characterize neuropathic pruritus in a cohort of patients with peripheral neuropathy.
• To investigate the relationship between pruritus, pain, and sensory/structural abnormalities in PNP.
• To assess the impact of pruritus and pain on mental health and quality of life.

Main Methods:

• A multicenter, cross-sectional observational study involving 191 PNP patients and 57 controls.
• Deep phenotyping included neurological examination, nerve conduction studies, quantitative sensory testing, and skin biopsies.
• Questionnaires assessed pruritus, pain, anxiety, depression, and quality of life.

Main Results:

• 11% of PNP patients reported pruritus as their sole symptom; 34.6% reported both pruritus and pain.
• Patients with pruritus showed increased cold detection thresholds, indicating Aδ-fiber dysfunction.
• The pruritus group exhibited lower intraepidermal nerve fiber density and more proximal symptom distribution.

Conclusions:

• Neuropathic pruritus is a significant symptom in peripheral neuropathy, often co-occurring with pain.
• Sensory and structural nerve abnormalities are associated with neuropathic pruritus.
• Neuropathic pruritus negatively impacts patients' anxiety levels and overall quality of life.