Presentation
Case Summary Our patient, a woman of Asian Indian descent aged 50 years, presented for a neuromuscular evaluation with complaints of imbalance. [karger.com]
Shy, MD1 Abstract Objective To analyze and describe atypical presentations of Charcot Marie Tooth disease type 4C (CMT 4C). [ncbi.nlm.nih.gov]
In summary, our 5-year-old female patient presented with clinical, electrophysiologic, and molecular genetic evidence supporting the diagnosis of CMT-4C. Her genetic mutation is a novel homozygous nonsense mutation of the SH3TC2 gene. [neupsykey.com]
Acronym CMT4C Synonyms Charcot-Marie-Tooth disease demyelinating autosomal recessive 4C Charcot-Marie-Tooth neuropathy type 4C Keywords Any medical or genetic information present in this entry is provided for research, educational and informational purposes [uniprot.org]
Entire Body System
- Difficulty Walking
Difficulty walking MedGen UID: 86319 •Concept ID: C0311394 • Finding Any persistent problem with walking. [ncbi.nlm.nih.gov]
She had difficulty walking in early childhood and at the age of 6 years was admitted to a hospital, where a diagnosis of polio was offered. In her teens, she was not able to run or walk and unable to participate in sports. [karger.com]
Musculoskeletal
- Small Hand
Power testing disclosed weakness and atrophy of the small hand muscles and grip. [karger.com]
Eyes
- Abnormal Eye Movement
Another important difference between CMT4C and FRDA are determined by the pattern of abnormal eye movements. Square wave jerks are the most common oculomotor abnormality in FRDA [10,11,12] whereas the presence of nystagmus in CMT4C is rare. [cerebellumandataxias.biomedcentral.com]
- Diplopia
The remainder of the neurological review of her systems was unremarkable, with no complaints of difficulty speaking, chewing, or swallowing or diplopia. Her general medical history was also unremarkable. [karger.com]
Neurologic
- Cerebellar Sign
The same mutation was found in the other 5 CMT4C patients (age range 32-80, all of European ancestry), none of them displayed cerebellar signs or atrophy. Another patient in this cohort was also diagnosed with FA during childhood. [mdsabstracts.org]
We reviewed a local cohort of 5 patients with CMT4C and suggest that (a) cerebellar signs associated with cerebellar atrophy may be considered within the phenotypic spectrum of CMT4C and (b) its early stages can mimic a “flaccid-ataxic” form of FRDA with [cerebellumandataxias.biomedcentral.com]
- Myokymia
Electromyograpy demonstrated reduction of motor units and myokymia with spontaneous regular rhythmic discharges of motor units in triplets or quadruples in facial muscles. In addition, myokymia activity was recorded in the facial muscles. [cerebellumandataxias.biomedcentral.com]
Striking features upon examination are nystagmus, broken smooth pursuit, myokymias, dysarthria and dysmetria in the upper limbs. A severe axonal and demyelinating sensory-motor polyneuropathy was found on neurography. [mdsabstracts.org]
- Hand Tremor
There is intermittent postural hand tremor. Other features shown are mild dysmetria, saccadic pursuit, bilateral gaze-evoked nystagmus, and hypermetric saccades. [cerebellumandataxias.biomedcentral.com]
- Slurred Speech
The patient also reported slurred speech and mild dysphagia. [cerebellumandataxias.biomedcentral.com]
- Ocular Flutter
Ocular flutter has been reported once in CMT4C [1]. [cerebellumandataxias.biomedcentral.com]
Treatment
It is not in any way intended to be used as a substitute for professional medical advice, diagnosis, treatment or care. Our staff consists of biologists and biochemists that are not trained to give medical advice. [uniprot.org]
Natural history and treatment of peripheral inherited neuropathies. Adv Exp Med Biol. 2009b;652:207–24. [ncbi.nlm.nih.gov]
Prognosis
PMID: 30907403Free PMC Article Prognosis Sivera R, Cavalle L, Vílchez JJ, Espinós C, Pérez Garrigues H, Sevilla T J Int Adv Otol 2017 Apr;13(1):93-99. doi: 10.5152/iao.2017.3379. [ncbi.nlm.nih.gov]
Etiology
Background: Establishing the etiology of hereditary ataxias is still challenging despite the use of mass sequencing. Ataxia can be a feature in complex syndromes such as hereditary spastic paraparesis and hereditary neuropathies. [mdsabstracts.org]
Etiology Audiol Neurootol 2018;23(6):326-334. Epub 2019 Jan 24 doi: 10.1159/000495176. [ncbi.nlm.nih.gov]
Dropped head syndrome: etiology and management.J Am Acad Orthop Surg. 2012; 20: 766-774 Martin A.R. Reddy R. Fehlings M.G. Dropped head syndrome: diagnosis and management.Evid Based Spine Care J. 2011; 2: 41-47 Lupo V. Galindo M.I. Martínez-Rubio D. [nmd-journal.com]
Epidemiology
Friedreich ataxia in Norway - an epidemiological, molecular and clinical study. Orphanet J Rare Dis. 2015;10:108. Article Google Scholar Aho TR, Wallace RC, Pitt AM, Sivakumar K. [cerebellumandataxias.biomedcentral.com]
Epidemiologic Study of Charcot-Marie-Tooth Disease: A Systematic Review. Neuroepidemiology (2016). doi:10.1159/000443706 Reilly, M. M. Axonal Charcot-Marie-Tooth disease: the fog is slowly lifting! [mda.org]
Supporting Materials: Study Protocol Statistical Analysis Plan (SAP) Informed Consent Form (ICF) Clinical Study Report (CSR) Analytic Code Time Frame: For Observational/Longitudinal/Natural History/Epidemiology studies): For the current grant cycle, available [clinicaltrials.gov]
Pathophysiology
Tyr680Cys mutation likely causes hypomyelination by affecting the interaction between SH3TC2 and protein(s) other than Rab11, for example, surface receptors in the SC membrane. 29, 30 Further functional studies of this missense mutation will clarify its pathophysiological [ncbi.nlm.nih.gov]
Taken together, NCS studies can give us insight to better understanding the underlying pathophysiological mechanism of CMT4C. The SH3TC2 protein contains 8 tetratricopeptide repeat (TPR) domains and 2 SH3 domains. [frontiersin.org]
Prevention
We prescribed 100 mg acetylsalicylic acid and 80 mg atorvastatin for secondary prevention of ischaemic stroke. [elsevier.es]