Presentation
The incidence is about 60% to present with the most severe form, which presents before 6 months of age, in what we call in the natural history type 1 SMA. But there are milder forms that could present at later times of life as well. [ajmc.com]
Severity of SMA is related to the number of SMN2 copies present. SMA type 1 patients usually have 2 copies of SMN2, while type IV patients usually have 3-4 copies. Inheritance : Autosomal recessive. [genetics4medics.com]
At birth, patients with SMA type 0 present with severe weakness and hypotonia. [mda.org]
However, at present, management remains symptomatic, involving a multidisciplinary approach and aiming to improve quality of life. Respiratory support is necessary. Physiotherapy and occupational therapy are recommended. [orpha.net]
In order to do so, the data of 141 patients presenting themselves with respiratory distress and the phenotype of a spinal muscular weakness was analyzed by hierarchical cluster analysis. [refubium.fu-berlin.de]
Entire Body System
- Feeding Difficulties
Poor sucking ability and reduced swallowing are frequent, leading to feeding difficulties. Deep tendon reflexes are absent. Respiratory failure is common. [orpha.net]
Symptoms are typically severe and may include hypotonia or diminished muscle tone, muscle weakness, respiratory problems, pneumonia, and swallowing and feeding difficulties. [ucsfbenioffchildrens.org]
feeding Breathing difficulty can rapidly become an emergency condition. [medlineplus.gov]
In the past, the treatment of SMA has been based on management of the complications of weakness, feeding problems and breathing difficulties. [rch.org.au]
- Difficulty Walking
While children with type 3 usually are able to walk, most have some difficulty walking. Some may eventually need to use a wheelchair. Symptoms usually appear around 18 months of age or in early childhood. [childrenshospital.org]
People with the condition: are able to stand and walk without help, although they may find walking or getting up from a sitting position difficult may have balance problems, difficulty running or climbing steps, and a slight shaking in their fingers may [nhs.uk]
People with type 4 may experience muscle twitches, muscle weakness and difficulty walking. They don’t usually have problems with breathing or swallowing and they usually have a normal life expectancy. What causes SMA? SMA is a genetic condition. [healthdirect.gov.au]
He will have difficulty walking, but will be able to sit independently and will likely live into the fifth decade of life 4 The child will have a progressive loss of alpha-motor neurons in anterior horn of spinal cord and will unlikely live past the age [orthobullets.com]
- Unable to Stand
Generally, affected children have difficulty sitting independently and are unable to stand and walk by the age of one year. The muscle weakness (almost always symmetrical) predominantly affects the legs and trunk muscles. [orpha.net]
Children are unable to stand without support and may be described as ‘sitters’. Their weak respiratory muscles can make it difficult for them to cough effectively, which can make them more vulnerable to chest (respiratory) infections. [smauk.org.uk]
These children may grow to sit unassisted but are often unable to stand or walk. [neurologytimes.com]
- Severe Pain
All patients had only axial pain, with lumbar and cervical muscle contracture, rigidity, and limited mobility. No one had neurologic symptoms. The most characteristic clinical finding was severe pain in the back during sneeze and percussion. [journals.sagepub.com]
- Surgical Procedure
OBJECTIVE: To describe the early and late postoperative data from SMA patients with surgical procedure. [atrofiaespinhal.org]
Respiratoric
- Pneumonia
Here, we report on two patients with SMA type 2 who repeatedly developed bronchitis and pneumonia. The patient in Case 1 was a 48-year-old female lacking exon 7 of the survival motor neuron gene (SMN) 1. [ncbi.nlm.nih.gov]
For example, as children with SMA type 1 are prone to respiratory infections and pneumonia, treatment focuses on trying to maintain their lung function and health. [betterhealth.vic.gov.au]
The severity of disease is related to the age of onset; type 1 SMA ( Werdnig-Hoffman disease) is associated with death within the first two years of life as a result of respiratory muscle paralysis or aspiration pneumonia. [amboss.com]
Involvement of respiratory muscles can lead to an increased tendency for pneumonia and other lung-related issues. This disease does not discriminate, as it affects men, women, and children. [muscle.ca]
Gastrointestinal
- Nausea
Since motor neurons do not divide, it is expected that the transgene may have long-term stability.[9][failed verification] Adverse effects[edit] Common adverse reactions may include nausea and increased liver enzymes.[2] Serious adverse reactions may [en.wikipedia.org]
- Failure to Thrive
These babies have increased risk of aspiration and failure to thrive. [mda.org]
Jaw & Teeth
- Fasciculation of the Tongue
[…] of the tongue Weakness and hypotonia in the limbs and trunk Intercostal muscle weakness (note, the diaphragm is initially spared) Paradoxical breathing Bell-shaped trunk with chest wall collapse and abdominal protrusion To learn how different aspects [togetherinsma-hcp.com]
Musculoskeletal
- Muscular Atrophy
短句来源 更多 Genetic diagnosis and gene sequencing of spinal muscular atrophy 脊髓性肌萎缩症基因诊断 短句来源 Objective:To investigate methods for prenatal diagnosis of spinal muscular atrophy. 目的:探讨脊髓性肌萎缩症(SMA)产前基因诊断的方法。 [dict.cnki.net]
N...Karaduman A 31111020 2019 35 Lumbosacral ventral spinal nerve root atrophy identified on MRI in a case of spinal muscular atrophy type II. 61 Smith G...Albayram MS 30340076 2019 36 [Respiratory care in spinal muscular atrophy in the new therapeutic [malacards.org]
atrophy SMN2 gene copy numbers are variable in individuals with spinal muscular atrophy. [togetherinsma-hcp.com]
Spinal Muscular Atrophy (SMA) Menu What is spinal muscular atrophy (SMA)? Spinal muscular atrophy (SMA) is a group of genetic diseases that cause weakness and wasting in the voluntary muscles of infants and children and, more rarely, in adults. [my.clevelandclinic.org]
Title Other Names: SMA2; Muscular atrophy, spinal, intermediate type; Muscular atrophy, spinal, infantile chronic form; SMA2; Muscular atrophy, spinal, intermediate type; Muscular atrophy, spinal, infantile chronic form; Spinal muscular atrophy type II [rarediseases.info.nih.gov]
- Muscle Weakness
Most of these patients develop foot deformities, scoliosis, and respiratory muscle weakness. [mda.org]
[…] have weak muscles, minimal muscle tone, and feeding and breathing problems. [medicalnewstoday.com]
The most common symptoms include clumsiness, trouble walking and climbing steps, fine tremor, and muscle weakness. Children with type 3 often have trouble getting up from a sitting position. [nm.org]
Children with SMA may have muscle weakness and poor muscle tone, and may not reach milestones such as sitting or crawling. [rch.org.au]
Neurologic
- Tremor
Tremor of hand Tremor of hands tremors in hands [ more ] 0002378 Muscle weakness Muscular weakness 0001324 Recurrent respiratory infections Frequent respiratory infections Multiple respiratory infections respiratory infections, recurrent Susceptibility [rarediseases.info.nih.gov]
Symptoms of adult-onset SMA are usually mild to moderate and include muscle weakness, tremor and twitching. How is spinal muscular atrophy diagnosed? To make a diagnosis of SMA, symptoms need to be present. [genome.gov]
The most common symptoms include clumsiness, trouble walking and climbing steps, fine tremor, and muscle weakness. Children with type 3 often have trouble getting up from a sitting position. [nm.org]
Fine tremors of the face are present in over 90% of patients. Type 2 diabetes mellitus, hand tremor, and infertility can also occur. [encyclopedia.com]
Children with the condition may: be able to sit up without help, but not stand or walk have weak arms or legs have shaking (tremors) in their fingers and hands later develop problems with their joints, such as an unusually curved spine (scoliosis) have [nhs.uk]
- Areflexia
Therefore, damage to lower motor neurons will subsequently result in hyporeflexia and/or areflexia.[1] Note that, in spinal shock, which is commonly seen in the transection of the spinal cord (Spinal cord injury), areflexia can transiently occur below [en.wikipedia.org]
The characteristics of this condition are hypotony and muscle weakness in limbs and trunk, respiratory problems, hyporeflexia or areflexia, trembling in the hands and muscle contractures. [riull.ull.es]
Patients typically present during infancy or early childhood with progressive weakness, hypotonia, muscle atrophy, hyporeflexia/areflexia, and varying degrees of bulbar weakness. [amboss.com]
Patients have diffuse, symmetric muscle weakness that is greater proximally and in the lower limbs; hyporeflexia or areflexia; and progressive respiratory insufficiency. [neurologytimes.com]
Hypotonia and areflexia Sensation and intelligence are normal. Diffuse muscle involvement involves all muscles except diaphram, sternohyoid, sternothyroid and involuntary muscles of heart, bladder, intestine, and sphincters. [gait.aidi.udel.edu]
- Hand Tremor
Tremor of hand Tremor of hands tremors in hands [ more ] 0002378 Muscle weakness Muscular weakness 0001324 Recurrent respiratory infections Frequent respiratory infections Multiple respiratory infections respiratory infections, recurrent Susceptibility [rarediseases.info.nih.gov]
They have delayed motor (physical) milestones, poor weight gain, weak cough, hand tremors, contractures (fixed deformities of joints) and scoliosis (curved spine). [rch.org.au]
Tongue movements and hand tremors may be seen, but are less apparent than in Type I SMA. Contractures (tightening) of joints and scoliosis are common. [choosept.com]
Fine tremors of the face are present in over 90% of patients. Type 2 diabetes mellitus, hand tremor, and infertility can also occur. [encyclopedia.com]
Muscle cramps, facial fasciculations, hand tremor. Associated with type 2 diabetes and infertility. [patient.info]
- Absent Deep Tendon Reflexes
Other symptoms may include: Decreased or absent deep tendon reflexes, such as the relfex that occurs when you tap on your knee. [ucsfbenioffchildrens.org]
Absent deep tendon reflexes, hypotonia, and weakness, but normal intelligence and no sensory loss are observed. Restricted joint mobility and kyphoscoliosis are also frequent. Death before age of 2 years old is common but does not always occur. [accessanesthesiology.mhmedical.com]
Signs of motor neuron disease such as muscle weakness, muscle atrophy, fasciculations, and reduced or absent deep tendon reflexes can be seen. [medlink.com]
These patients had symmetrical or asymmetrical predominantly proximal muscle weakness and wasting and particularly affecting the lower limbs with tremor of the hands and generalized markedly reduced or absent deep tendon reflexes. [neurologyindia.com]
- Flaccid Paralysis
These patients present by hypotonia, symmetrical flaccid paralysis, no head control and poor suck and swallow, with increasing swallowing and feeding difficulty over time due to involvement of bulbar motoneurons. They present before 6 months of age. [raredisorders.imedpub.com]
Treatment
“Critically, the Working Group notes that the loss of even a small number of motor neurons is unacceptable when effective treatment is available, as this loss cannot be reversed after onset but can be prevented with earlier treatment.” [neurologylive.com]
However, response to treatment does vary. [rarediseases.info.nih.gov]
Treatment The only treatment approved by the U.S. Food and Drug Administration for SMA is Spinraza (nusinersen). However, there are other treatments available to ease symptoms and improve quality of life. [smanewstoday.com]
Management and treatment Clinical trials are ongoing to identify potential drug treatments for SMA2, mainly targeted towards increasing the levels of the full length SMN protein. [orpha.net]
[…] to treatment during the trial period. [cochrane.org]
Prognosis
AVXS-101) which hold promise in improving the quality of life and prognosis of these patients 7-9. [radiopaedia.org]
Prognosis The prognosis is generally poor with most patients dying within the first two years of life due to respiratory failure. However, in some cases, manifestations are stable or even regress, and patients may live longer. [orpha.net]
Prognosis The prognosis depends on the severity of the disease, which generally correlates with the age of onset: earlier-onset forms are generally associated with a poor prognosis, whereas life expectancy may be close to normal in later-onset forms. [rarediseases.info.nih.gov]
Etiology
Etiology Pathophysiology Clinical features The most common causes of death among patients with SMA are respiratory insufficiency (due to respiratory muscle weakness ) and aspiration pneumonia (due to bulbar weakness)! [amboss.com]
Etiology Similarly to the other forms of SMA, SMA2 is primarily caused by deletions in the SMN1 gene (5q12.2-q13.3) encoding the SMN (survival motor neuron) protein. [orpha.net]
The most common form of spinal muscular atrophy (SMA) is a recessive disorder caused by deleterious SMN1 mutations in 5q13, whereas the genetic etiologies of non-5q SMA are very heterogeneous and largely remain to be elucidated. [uniprot.org]
Epidemiology
Summary Epidemiology Prevalence is estimated at around 1/70,000. The disease is slightly more frequent in males than in females. Clinical description Disease onset occurs between the ages of 6 and 18 months (usually around 15 months). [orpha.net]
Epidemiology References: [1] [2] [3] Epidemiological data refers to the US, unless otherwise specified. [amboss.com]
Pathophysiology
Identification of the molecular pathophysiology of lower motor neuron syndromes can be expected to aid in the development of therapy for these disabling disorders. [dpag.ox.ac.uk]
Farrar MA, Vucic S, Johnston HM, duSart D, Kiernan MC (2013) Pathophysiological insights derived by natural history and motor function of spinal muscular atrophy. J Pediatrics 162: 155-159. [smauk.org.uk]
Etiology Pathophysiology Clinical features The most common causes of death among patients with SMA are respiratory insufficiency (due to respiratory muscle weakness ) and aspiration pneumonia (due to bulbar weakness)! [amboss.com]
Pathophysiological insights derived by natural history and motor function of spinal muscular atrophy. J Pediatr. 2013;162:155-9. https://doi.org/10.1016/j.jpeds.2012.05.067 Lin CW, Kalb SJ, Yeh WS. [revistabiomedica.org]
Pathophysiology In 1995, the spinal muscular atrophy disease-causing gene, termed the survival motor neuron (SMN), was discovered. [9] Each individual has 2 SMN genes, SMN1 and SMN2. [emedicine.medscape.com]
Prevention
This article discusses the primary respiratory complications of spinal muscular atrophy type 2 and the role of respiratory interventions to promote growth and development, improve cough efficacy, reverse nocturnal hypoventilation, and prevent and treat [ncbi.nlm.nih.gov]
Scientists hope to characterize the genes, study gene function and disease course, and find ways to prevent, treat, and, ultimately, cure these diseases. [christopherreeve.org]
The individual may have scoliosis or contractures, a shortening of the muscles or tendons, which can prevent the joints from moving freely. [medicalnewstoday.com]
Standing programs for children who can't walk are used to maintain muscle flexibility and length, prevent contractures, promote musculoskeletal development, and prevent bone-mineral density loss. [choosept.com]
Those affected by the disorder can work with their health care providers to manage SMA symptoms and prevent complications, which can contribute to quality of life. [hopkinsmedicine.org]