Trigeminal Neuralgia and Charcot-Marie-Tooth Disease: An Intriguing Association. Lessons From a Large Family Case Report and Review of Literature.

We report a case of familial trigeminal neuralgia (TN) and Charcot-Marie-Tooth disease (CMT) caused by an identified MPZ mutation with a review of previous cases described in the literature. Background The association of TN in CMT patients has previously been reported in a few cases. The pathophysiological link can be detailed with recent use of genetic analysis in CMT. Methods We report a large family including 7 members affected by CMT, 4 of whom also presented with TN. We then performed a literature review of literature by search of Pubmed from 1950 to September 2018, using the search terms "trigeminal neuralgia" and "Charcot-Marie-Tooth" and the references of relevant articles. Results Overall, we found 29 previously published TN cases in 12 CMT families. Among them, only 7 families (69%) included several affected members, suggesting that not all mutations involved in CMT predispose to TN. TN in this context seems to present with specific characteristics, including earlier age of onset, bilateral presentation, and poor tolerance to preventive treatments with gait disturbance exacerbated by the underlying neuropathy. Conclusion This report of familial TN in CMT with identified MPZ mutation highlighted specific characteristics of this association. Considered as a rare association in the literature, it may be underestimated and the clinician should be aware of its specific pattern, including earlier age of onset, bilateral presentation, and poor tolerance to preventive treatments.