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]

These children present with significant weakness and generalized hypotonia which manifests in difficulty moving, swallowing, feeding and breathing. The neck, shoulder girdle, chest and pelvis demonstrate the greatest weakness. [columbiasma.org]

• Recurrent Upper Respiratory Infection

  Past medical history significant for recurrent upper respiratory infections occasionally requiring hospitalization. [gait.aidi.udel.edu]

• Decreased Breath Sounds

  At this time she looked alert, having sever ehypotonia, frog like position, seesaw breathing, with decreased breath sounds on the right side of the chest. The case was admitted to PICU and connected to mechanical ventilation. [raredisorders.imedpub.com]

• 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]

• Long Legs

  Managed with physical therapy and inpatient rehabilitation consisting of intensive physical, occupational and aquatic therapy and the use of long leg braces at age of 2. [gait.aidi.udel.edu]

• Ankylosis

  Airway management was further complicated by limited mouth opening and cervical spine ankylosis. Copyright © 2017 Elsevier Ltd. All rights reserved. KEYWORDS: Airway; Dexmedetomidine; Spinal muscular atrophy [ncbi.nlm.nih.gov]

• Type A Personality

  Assistive devices and therapy Various types of assistive device can improve a person’s life expectancy and quality of life with SMA. [medicalnewstoday.com]

• 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]

• Gowers Sign

  […] from 6 months to 24 months of age Less involved than Type I, will sit, but will never walk May live 30 to 40 years Type III: Kugelberg-Welander Disease Onset from 2 to 10 years of age Usually walk until late childhood or early adolescence, never run + Gower [gait.aidi.udel.edu]

• Gliosis

  Postmortem findings included decreased numbers of motor neurons and gliosis in the anterior horns of the spinal cord and motor cranial nerve nuclei 5 and 7 to 12 (Hausmanowa-Petrusewicz et al 1980). [medlink.com]

  On pathological examination of the spinal cord we found ballooned neurons, neuronophagia and gliosis in family A, which have been regarded as characteristic pathological features of infantile-onset spinal muscular atrophy (SMA). [dict.cnki.net]

“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]

As these treatments are new, nobody has any long-term experience with them, and this means that we do not know what the outcome will be years after treatment. Heidi Moawad, MD Answers represent the opinions of our medical experts. [medicalnewstoday.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]

Our result demonstrates that administration of BTA is one of the effective treatment choices for dysphagia in SMA patients. [ncbi.nlm.nih.gov]

AVXS-101) which hold promise in improving the quality of life and prognosis of these patients 7-9. [radiopaedia.org]

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]

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]

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]

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]

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]

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]

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]

The individual may have scoliosis or contractures, a shortening of the muscles or tendons, which can prevent the joints from moving freely. [medicalnewstoday.com]

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]

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]