Down‐regulation of receptors for semaphorins and VEGF in a transgenic model of CMT1A

Abstract

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