HINT1 Neuropathy in Latvia: Clinical, Genetic, and Functional Profiling

  • Rozevska, M. (Speaker)
  • Dmitrijs Rots (Co-author)
  • Gailīte, L. (Co-author)
  • Ronalds Linde (Co-author)
  • Staņislavs Mironovs (Co-author)
  • Maksims Timčenko (Co-author)
  • Viktors Ļiņovs (Co-author)
  • Dzintra Locmele (Co-author)
  • Mičule, I. (Co-author)
  • Baiba Lāce (Co-author)
  • Ķēniņa, V. (Co-author)

Activity: Talk or presentation types › Poster presentation

Description

HINT1 variants are associated with autosomal recessive axonal neuropathy with neuromyotonia. Patients with the HINT1 gene variant demonstrate gradual development of motor-greater-than-sensory polyneuropathy, over time, hand muscle relaxation difficulties develop. The majority of patients are compound heterozygous or homozygous for a Slavic founder variant (c.110G>C, p.Arg37Pro).  In Latvia, the frequency of variant p.Arg37Pro is the highest known so far. This is the first systematic assessment of HINT1 neuropathy in Latvia.. All patients diagnosed with axonal neuropathy with neuromyotonia (HINT1—neuropathy) in Latvia (n = 10) from geneticists, neurologists and paediatric neurologists’ clinical practices were recruited into this study. Axonal neuropathy with neuromyotonia was diagnosed based on clinical symptoms, a neurophysiological examination and positive genetic testing.. To assess the phenotypes of HINT1 neuropathy patients, we analyzed 10 patients diagnosed with axonal neuropathy with neuromyotonia—2 male and 8 female—with ages ranging from 13 to 64 years.  In all cases, nerve conduction velocities were nearly normal, with a severe decrease in motor amplitudes, and concentric needle EMG displayed neuromyotonic discharges. In the patient group with pure motor axonal neuropathy, myotonic symptoms in the legs were more severe, with spastic gait disturbances.  Ultrasonography was performed on 4 patients out of 10 who had HINT1 neuropathy. The nerve cross-sectional areas of the median and ulnar nerves were closer to the lower limits of the normal value. None of the investigated nerves had structural changes. In all patients with HINT1 neuropathy, ultrasound examination showed significantly reduced muscle volume as well as spontaneous fasciculations and fibrillations.. Our study is the first detailed ultrasonographic evaluation of patients with HINT1 axonal polyneuropathy. The best-known and most widespread disease-associated variant is p.Arg37Pro. Overall, the genetic epidemiology suggests that HINT1 neuropathy should be considered in the diagnostic work-up of patients of European descent presenting with axonal CMT.
Period29 Mar 2023
Event titleRSU International Research Conference 2023: Knowledge for Use in Practice
Event typeConference
OrganiserRīga Stradiņš University
LocationRiga, LatviaShow on map
Degree of RecognitionInternational

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