Is Small Fiber Neuropathy Induced by Gadolinium-Based Contrast Agents?

Area of Science:

• Neuroscience
• Radiology
• Toxicology

Background:

• Patient complaints of burning pain in extremities after gadolinium-based contrast agent (GBCA) injections are increasing.
• The underlying cause of GBCA-associated pain remains unclear.

Purpose of the Study:

• To investigate the effect of GBCAs on small epidermal nerve fibers in a mouse model.
• To compare the neurotoxic potential of macrocyclic and linear GBCAs.

Main Methods:

• Mice received intravenous injections of macrocyclic GBCAs, linear GBCAs, or saline.
• Footpads were analyzed for intraepidermal nerve fiber density (IENFD) and terminal axonal swellings (TASs) using immunofluorescence staining.

Main Results:

• All GBCAs significantly reduced IENFD compared to controls.
• Linear GBCAs caused a greater reduction in IENFD and a significant increase in TASs compared to macrocyclic GBCAs.
• Macrocyclic GBCAs did not significantly increase TASs.

Conclusions:

• GBCAs, particularly linear agents, can induce small fiber neuropathy in mice.
• Further research is needed to determine the clinical relevance and dosage thresholds for these findings in humans.