Presentation
Neuromuscular syndromes are presented clinically either as a case study or as an overview from the literature, accompanied by text presenting molecular defects, and differential diagnosis. [books.google.com]
Differential diagnosis and investigation of respiratory muscle weakness according to clinical presentation Patients presenting with respiratory muscle weakness will typically have nocturnal symptoms including orthopnea, sleep disruption, and headache [dovepress.com]
The onset usually occurs in adult life (between the second and fourth decade) but may be congenital or present in early childhood. [medlink.com]
Patients typically present with proximal muscle weakness of legs more than arms, with no sensory involvement. [clevelandclinicmeded.com]
Distal muscle weakness is present in about 80% of individuals. [ncbi.nlm.nih.gov]
Entire Body System
- Weakness
Neurologic exam revealed thinning of the anterior legs, bilateral calf hypertrophy, neck flexor and extensor weakness, distal greater than proximal weakness in the legs, and proximal weakness in the arms. CK level was mildly elevated at 318 U/L. [neurology.org]
This disease also causes intense weakness in the thorax muscles involved in breathing, particularly the diaphragm. This weakness leads to respiratory problems and respiratory failure that can be potentially fatal. [ivami.com]
This weakness worsens over time and can lead to life-threatening respiratory failure. [ghr.nlm.nih.gov]
[…] muscle weakness Mainly manifests with ophthalmoparesis and with bulbar weakness manifesting with dysarthria and dysphagia Facioscapulohumeral muscular dystrophy Approximately 4 per 100,000 population Face and arm weakness, scapular winging, and later [clevelandclinicmeded.com]
weak Proximal legs may become weak late in disease Quadriceps weak in rare male Many remain ambulatory Earlier onset (2nd decade) may lose ambulation in 3rd to 6th decade Homozygotes: Loss of ambulation by 3rd decade Cardiomyopathy Laboratory CK: Mild [neuromuscular.wustl.edu]
- Difficulty Walking
Among the earliest signs of the condition are breathing problems and difficulty walking. [ghr.nlm.nih.gov]
Affected muscle groups: Proximal muscle groups - difficulty rising from chair, climbing stairs, shaving, hair combing. Distal muscles - difficulty walking (flapping gait), grasping, handwriting. [patient.info]
Signs and symptoms [ edit ] Some early signs of HIBMs includes: Difficulty walking on heels, and difficulty running; Weak index finger; Frequent loss of balance. [en.wikipedia.org]
Respiratoric
- Respiratory Insufficiency
Design/Methods: Case report Results: A 29-year-old Afghan woman with no family history of muscle disease who developed proximal limbgirdle weakness in her early 20s that slowly progressed to prominent distal weakness and respiratory insufficiency (FVC [neurology.org]
Respiratory function test revealed restrictive respiratory insufficiency that was treated with nocturnal ventilation support. [bmcneurol.biomedcentral.com]
Falga-Tirado C, Perez-Peman P, Ordi-Ros J, Bofill JM, Balcells E (1995) Adult onset of nemaline myopathy presenting as respiratory insufficiency. Respiration 62(6):353–354 PubMed CrossRef Google Scholar 112. [link.springer.com]
Early involvement of the tibialis anterior is also common, except for the Portuguese family, who reported isolated respiratory insufficiency and a milder presentation of HMERF. [nature.com]
Differential Diagnosis Late-onset glycogen storage disease type II (GSD II) is characterized by proximal muscle weakness and respiratory insufficiency. Inheritance is autosomal recessive. [ncbi.nlm.nih.gov]
- Respiratory Abnormalities
In the process of genetic testing of patients with myofibrillar myopathy (MFM) we encountered familial and sporadic cases of skeletal myopathy with or without associated respiratory abnormalities who lack mutations in MFM-associated genes [ 26, 27 ]. [bmcneurol.biomedcentral.com]
Musculoskeletal
- Myopathy
[…] with respiratory muscle involvement regardless of ethnic background Respiratory failure in adult myopathy patients is rare. [jnnp.bmj.com]
Edstrom myopathy HMERF myopathy, proximal, with early respiratory muscle involvement Hedberg C, Toledo AG, Gustafsson CM, Larson G, Oldfors A, Macao B. [ghr.nlm.nih.gov]
Hereditary myopathy with early respiratory failure (HMERF) - TTN gene Hereditary myopathy with early respiratory failure (HMERF) is a hereditary muscular disease that predominantly affects the proximal muscles and muscles that are needed to breathe. [ivami.com]
Background: Hereditary myopathy with early respiratory failure is a rare dominantly inherited muscle disease characterized by slowly progressive proximal weakness and respiratory involvement at onset. [neurology.org]
TDP-43-stained aggregates were also found in affected muscle fibres in rimmed vacuolar myopathies, including inclusion body myositis, GNE myopathy, myofibrillar myopathies, and oculopharyngeal muscular dystrophy [ 36 – 38 ]. [bmcneurol.biomedcentral.com]
- Leg Weakness
The first symptoms usually relate to weakness of the distal leg muscles and may include foot drop or frequent falls. [ncbi.nlm.nih.gov]
2J Distribution of weakness Legs: Anterior tibial selectively involved Arms Never hand weakness in Finnish patients Some Non-Scandinavian families with hand weakness Proximal weakness: 15%; Mild Progression Slow: Foot drop 10 to 15 years after onset [neuromuscular.wustl.edu]
The weakness and severity can vary from person to person. In some, weakness in the legs is noticed first. In few others, the hands are weakened more rapidly than the legs. Weakness is progressive, which means the muscle becomes weaker over time. [en.wikipedia.org]
- Long Arm
This process is usually due to mutations in the TTN (titin) gene, located on the long arm of chromosome 2 (2q31.2); however, in rare cases, people with the characteristics of HMERF do not have mutations identified in this gene and the cause of the disease [ivami.com]
Psychiatrical
- Suggestibility
Key points for each genetic disease are identified to suggest treatment, when available, or the main clinical exams useful in follow-up of patients. [books.google.com]
Two reports by Palmio et al 1 and Pfeffer et al 2 suggest that hereditary myopathy with early respiratory failure (HMERF) may not be rare and is distributed worldwide. [jnnp.bmj.com]
Acuteness of symptoms: Weakness over hours suggests a toxic cause or episodic paralysis. Weakness developing over days - consider dermatomyositis or rhabdomyolysis. Weakness over weeks suggests polymyositis, steroid myopathy, endocrine myopathy. [patient.info]
These results suggested that this rare mutation in TTN segregated with the disease in this family. [nature.com]
A combination of distal and proximal weakness, cardiomyopathy, peripheral neuropathy, and autosomal dominant inheritance should suggest this disorder ( Nakano et al 1996 ). [medlink.com]
Neurologic
- Foot Drop
Some affected individuals have weakness of muscles of the lower leg and foot, which makes it difficult to lift the toes while walking, a condition known as foot drop. [ghr.nlm.nih.gov]
drop Hypotonia Weakness: Intrafamilial variation Legs Ankle dorsiflexion: Often severe with foot drop Hanging big toe Proximal muscles may be involved Neck: Sternocleidomastoids & Neck flexors Hands Finger (esp 5th) & Wrist extensors Onset age: 3rd to [neuromuscular.wustl.edu]
drop can be through the use of Ankle Foot Orthoses (AFOs) which can be designed or selected by an Orthotist based upon clinical need of the individual. [en.wikipedia.org]
GNE-related myopathy (IBM2) typically presents in the late teens to early adulthood with slowly progressive distal muscle weakness involving gait disturbance and foot drop secondary to anterior tibialis muscle weakness. [invitae.com]
Her gait was waddling and she had bilateral foot drop. No muscle atrophies or hypertrophies were observed (Table 1 ). CK levels were 2-fold-increased. [bmcneurol.biomedcentral.com]
- Limb Weakness
Cardiomyopathy, Dilated, 1f And Limb-Girdle Muscular Dystrophy Type 1d, Formerly. CMD1f And LGMD1d, Formerly. [en.wikipedia.org]
HMERF typically presents with respiratory muscle weakness in patients who are still ambulant. Limb weakness is most prominent in the tibialis anterior. [dovepress.com]
[…] subsequently progressing to proximal limb weakness were also screened for TTN mutations. [bmcneurol.biomedcentral.com]
- Waddling Gait
Waddling gait of Duchenne muscular dystrophy at age 3-6 years is typical. Acuteness of symptoms: Weakness over hours suggests a toxic cause or episodic paralysis. Weakness developing over days - consider dermatomyositis or rhabdomyolysis. [patient.info]
- Steppage Gait
Altered structure of thick filament Clinical Features "Hanging" Big Toes Patient is attempting to dorsiflex toes Onset Age Common: Childhood or Young adult; 1.5 to 26 years Occasional: Neonatal or 6th decade Interfamilial variation Distal leg weakness: Steppage [neuromuscular.wustl.edu]
Treatment
You may need treatment in intensive care unit at a hospital. Chronic respiratory failure can often be treated at home. But if your chronic respiratory failure is severe, you might need treatment in a long-term care center. [medlineplus.gov]
Key points for each genetic disease are identified to suggest treatment, when available, or the main clinical exams useful in follow-up of patients. [books.google.com]
In acquired myopathies, treatment is targeted toward the underlying cause. Treatment of statin myopathies is dependent on creatine phosphokinase levels and degree of muscle symptoms. Consider lower doses when initiating statin therapy. [clevelandclinicmeded.com]
You may receive oxygen therapy and other treatment to help you breathe. NIH: National Heart, Lung, and Blood Institute Acute respiratory distress syndrome (Medical Encyclopedia) Respiratory acidosis (Medical Encyclopedia) [ Read More ] [icdlist.com]
Another protein, neural cell adhesion molecule is under-sialyated in people with IBM, but as of 2016 it had no known role in muscle function. [1] Treatment [ edit ] Treatment is palliative, not curative (as of 2009). [16] Treatment options for lower limb [en.wikipedia.org]
Prognosis
Prognosis This depends on the specific diagnosis. The primary disorders are incurable conditions with varied prognosis. Secondary myopathy may be corrected by treating the underlying cause. [patient.info]
Prognosis [ edit ] A 2009 review noted that muscle weakness usually begins after age 20 and after 20–30 years, the person usually requires a wheel chair for mobility. [en.wikipedia.org]
Prognosis of amyotrophic lateral sclerosis with respiratory onset. J Neurol Neurosurg Psychiatry. 2007;78(6):629–631. 10. Brooks BR, Miller RG, Swash M, Munsat TL. [dovepress.com]
In cases suspected to be a primary inflammatory myopathy, specific autoantibodies can be considered to determine the prognosis and rule out associated conditions. [clevelandclinicmeded.com]
ALS with respiratory onset: Clinical features and effects of non-invasive ventilation on the prognosis. Amyotroph Lateral Scler. 2010; 11 :379–82. [ PubMed : 20001486 ] Hedberg C, Melberg A, Dahlbom K, Oldfors A. [ncbi.nlm.nih.gov]
Etiology
Rhabdomyolysis may also be seen with infectious etiologies, alcohol, and toxic exposures. [clevelandclinicmeded.com]
^ Carrillo N, Malicdan MC, Huizing M (2018) GNE myopathy: Etiology, diagnosis, and therapeutic challenges. Neurotherapeutics doi: 10.1007/s13311-018-0671-y ^ "Inclusion body myopathy 3". NIH Genetic and Rare Diseases Information Center. [en.wikipedia.org]
Oculopharyngodistal myopathy This condition is associated with both autosomal dominant and recessive inheritance, and the genetic etiology is unknown. 12 Respiratory failure in ambulant patients is common in this condition, and clinical presentation includes [dovepress.com]
However, the underlying genetic etiology in this family was unknown. The aim of this study was to determine the genetic cause in this family. To identify the responsible genetic mutation, we performed linkage analysis and whole-exome sequencing. [nature.com]
Prevalence The prevalence of HMERF is not known, but it is most likely underrecognized because of its broad phenotypic spectrum and the very recent discovery of its underlying genetic etiology. [ncbi.nlm.nih.gov]
Epidemiology
3 Dutch families Gowers (Laing; Early adult onset distal myopathy type III; MPD1) 3, 4 ● Myosin heavy chain 7 (MYH7) ; Chromosome 14q11.2; Dominant or Sporadic Epidemiology Australian, German, Italian & Austrian families Genetics: MYH7 mutations Types [neuromuscular.wustl.edu]
Epidemiology These are all relatively uncommon diseases: Duchenne muscular dystrophy is easily the most common childhood-onset muscular dystrophy and affects 1 in 3,300 boys. [ 6 ] The prevalence of Duchenne muscular dystrophy is 63 cases per million. [patient.info]
Table 1 Clinical Features of Common Myopathies Myopathy Epidemiology Distribution of Weakness Other Systemic Manifestations Acquired Myopathies Dermatomyositis Female > male Peak incidence: children and ages 40–60 yr Symmetrical proximal muscle weakness [clevelandclinicmeded.com]
Jones & Jianbo Yao Canine Genetics and Epidemiology (2017) Performance comparison of two commercial human whole-exome capture systems on formalin-fixed paraffin-embedded lung adenocarcinoma samples Silvia Bonfiglio, Irene Vanni, Valeria Rossella, Anna [nature.com]
Pathophysiology
The pathophysiology is still unclear. Cardiac involvement may occur. [en.wikipedia.org]
Back to Top Pathophysiology Disruption of the structural integrity and metabolic processes of muscle cells can result from genetic abnormalities, toxins, inflammation, infection, and hormonal and electrolyte imbalances. [clevelandclinicmeded.com]
Prevention
Prevention Genetic counselling is, in some of the most common myopathies such as Duchenne muscular dystrophy, the only intervention that can prevent disease. In general: Give genetic counselling early. [patient.info]
In patients with an underlying metabolic myopathy, education about following a more moderate exercise program and avoiding intense exercise and fasting is necessary in preventing recurrent episodes. [clevelandclinicmeded.com]
Some of these conditions have disease-modifying treatment available, but even in the absence of such therapy, the management of respiratory failure with supportive care such as NIV and cough assist is recommended to improve quality of life and prevent [dovepress.com]
Exercises and activities suggested by physiotherapy consultation may be helpful to prevent continued loss of physical function due to inactivity. [ncbi.nlm.nih.gov]