Case Report: A 20-year-old man presented for evaluation following an episode of painless injury in which he almost amputated his thumb. Upon further questioning, the patient reported he rarely experienced physical (including visceral) pain and his mother provided support to his history recalling incidents occurring as a child. He does not experience itching either. His neurologic and general medical history was otherwise negative. His neurologic and general examination were unremarkable except for the inability to perceive painful (pinprick, pressure on Achilles' tendons), hot and cold stimuli over his entire body, with some relative sparing over his chest, abdomen and back. Nerve conduction studies and needle examinations were normal. Quantitative sensory testing revealed normal threshold to vibration, relatively elevated threshold to cold and insensitivity to heat and pain. Autonomic reflex screen and thermoregulatory sweat test were normal. Sural nerve biopsy showed normal myelinated and unmyelinated fibers. MRI of head and cervical spine, and extensive laboratory testing were unremarkable. Conclusion: This patient differs from any other case described in the literature of pain insensitivity or pain indifference. Suspecting a central pathology, we prescribed naltrexone and retested his heat-pain sensation after treatment. He perceived the probe as hotter. Unfortunately, he suffered unacceptable dysthymia from the medication and stopped it. RAT IN VIVO MODELS OF TAXANES' PERIPHERAL NEUROTOXICITY FOLLOWING CHRONIC INTRAVENOUS ADMINISTRATION
X‐linked Charcot‐Marie‐Tooth is an inherited motor and sensory neuropathy associated with mutations in GJB1, a gene on chromosome X coding for the gap junction protein “connexin 32” (Cx32). Cx 32 gene is expressed in both peripheral and central nervous system myelin. We describe a family affected by X‐linked CMT neuropathy with a novel point mutation in Cx32 gene, in which the mother, the putative carrier, and three affected sons were examined. The affected sons (32, 35, 38 yrs) presented a motor‐sensory slowly progressive neuropathy mainly involving lower limbs. Nerve conduction study showed both axonal and demyelinating pattern of denervation. Evoked potentials indicated visual and brainstem auditory pathway involvement. The mother showed subclinical electrophysiological abnormalities in nerve conduction velocities. By mutational analysis of GJB1 using SSCP and sequencing of candidate regions, a previously undescribed missense mutation in the exon 2, codon 151, was found. This mutation was due to a transversion (TAT‐> TCT) leading to a Tyr‐>Ser substitution in the 2nd extracellular domain. Our findings further stress the wide variability in the spectrum of Cx32 mutations associated to CMTX, making it worthwhile to deepen knowledge about genotypic–phenotypic interrelationship in this disease.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.