Congenital muscular dystrophy

Congenital muscular dystrophies is autosomal recessively inherited diseases which are a group of heterogeneous disorders.^[1] Characterised by the muscle weakness which is present at birth and the different changes on muscle biopsy that ranges from myopathic to overtly dystrophic due to the muscle biopsied and the age at which the biopsy takes place.^[2]

Signs and Symptoms

Most infants with CMD will display some progressive muscle weakness, although there can be different degrees and symptoms of severeness of progression. The weakness is indicated as hypotonia, or lack of muscle tone, which can make an infant seem unstable. Later, infants and toddlers may be slow with their motor skills; such as rolling over, sitting up or walking, or may not even reach this milestones in life. Some of the more rarer forms of CMD can result in significant learning disabilities, or mental adjotmnet. For more information see the table of 20 different types of congenital Muscular dystorphies.^[3]

20 Different types of Congenital Muscular dystrophies

CMD with adducted (drawn inward) thumbs, ophthalmoplegia (paralyzed eye muscles) and intellectual disability.

A rare form of CMD causing permanent shortening of the toe joints and lack of muscle tone which can delay walking due to being weak also paralysis of eye muscles and intellectual disability which effects their way of processing information.^[4]

CMD with cardiomyopathy

First year of a newborn begins with weakness, which affects motive skills, walking can be accomplished in adolescence, deformity and rigidity of joints the joints, neck and spine; progressive cardiomyopathy at the ages of 5 to 12; cardiac rhythm abnormalities. ^[4]

CMD with central nervous system atrophy and absence of large myelinated fibers in peripheral nervous system.

At the beginning of the newborn period, the issues the infant receives are; poor muscle tone, weak motor function; respiratory failure in a few infants; major parts of the brain are formed smaller; deformity and rigidity joints.^[4]

CMD with cerebellar atrophy (diminished size of thecerebellum, a part of the brain involved in motor control)

Unprogressive form of CMD at the beginning period by seven months which causes weakness, poor muscle tone, delayed in motor milestones, lack of coordination in motive skills, difficulty speaking, involuntary eye movements and intellectual disability.^[4]

CMD with desmin inclusions (abnormal accumulations of the muscle protein desmin in some muscle fibers)

At the beginning a progressive weakness and low muscle tone at birth or during early infancy; small muscles; cardiac abnormalities in some; which can then progress to spinal curvatures at 8-14 years also deformity and rigidity joints, respiratory impairment.^[4]

CMD with integrin alpha 7 mutations

At birth low muscle tone, have weakness, perhaps walk at age of 2-3years old; respiratory involvement with disease progression.^[4]

CMD with joint hyperlaxity (abnormally flexible joints)

Weakness and deformity and rigidity joints present at birth, poor muscle tone, slowly progressive; can be walking at 1-3 years but might progress into a wheelchair later somewhere between teens and 30s; reduced respiratory capacity may have a lack of progression, abnormal flexibility in others, spinal curvature possible, still remain with normal intelligence.^[4]

CMD with familial junctional epidermolysis bullosa

Some of the symptoms at birth and though out the infants life are weakness or poor muscle tone, with skin blistering, skin blisters with injury and heat, slowly progressive, by age 10 they need a wheelchair, elbow deformity, respiratory impairment, cardiomyopathy, deformity of the brain, treatment with 3,4-diaminopyridine, which increases signal transmission from nerve to muscle.^[4]

CMD with muscle hypertrophy (enlargement of muscles)

Weak muscle tone starting in first weeks of the infant, unassisted when sitting but would have not accomplished walking, some muscles maybe enlarged, especially calf muscles; other muscles maybe small, such as the shoulder area; deformity and rigidity in some joints the cognitive function usually normal might suffer from a mild intellectual disability or speech problems my exist. ^[4]

CMD with muscle hypertrophy and respiratory failure

At birth the infant will have weakness with involvement of the diaphragm and respiratory failure, can be walking at 1.5 to 2.5 years old, a good percentage of muscle enlargement; deformity in ankles, spinal rigidity in about 50 percent and will have normal intelligence.^[4]

CMD with muscle hypertrophy and severe intellectual disability

Around the beginning of 5 months the infant will have some issues with low muscle tone and weakness, some muscles could be enlarged and global developmental could be delay, intellectual disability; deformity of ankles and elbows.^[4]

CMD with myasthenic syndrome

Rare form of CMD by time of birth can cause weakness, lack of muscle tone, small muscles, slowly progressive, respiratory involvement possible, most children and adults are able to walk and have normal intelligence.^[4]

CMD with (early) spinal rigidity

Present at birth to 1 year can have poor muscle tone and weakness, reduced respiratory capacity, muscles could be deformed, beginning ages 3-7 stabilization or slow decline spinal rigidity, limited mobility to flex the neck and spine, spinal curvature beginning ages 4-12 and progressing, deformity and rigidity joints, minor cardiac abnormalities, normal intelligence.^[4]

CMD with spinal rigidity and lamin A/C abnormality

With in the first year the infant is weak, there is respiratory involvement, rigid spine, curved spine, curved feet, cardiac rhythm abnormalities in some, premature aging in some and abnormalities of fatty tissue in some infants.^[4]

CMD with spinal rigidity and selenoprotein deficiency

Present at birth is weakness in the muscles, developmental delay, reduced respiratory capacity, fatigue, skin abnormalities, hearing loss, rigid spine.^[4]

CMD with structural abnormalities of mitochondria (energy-producing subunits of cells)

Weakness which is present at birth, poor muscle tone with late walking, loss of muscle tissue, cardiomyopathy, intellectual disability, mitochondria which are enlarged and have an abnormal structure.^[4]

Fukuyama CMD

In western countries this type of CMD is rare but is common in Japan. The effects this disease has on infants is spectrum of severity, weakness in muscle tone within first year, some infants may achieve some walking, have deformity and rigidity joints, spinal curvatures, seizures in 50%, eye involvement and intellectual disability.^[4]

Merosin-deficient CMD

Present at birth weakness in muscle tone, spectrum of severity; some may learn to walk at age 2-3 years, spinal curvature, deformity and rigidity joints, respiratory impairment, intelligence can often be normal; seizures in about 20% all these are the issues that infants face with this type of CMD.^[4]

Merosin-positive CMD

Some forms of merosin-positive CMD are: Early spinal rigidity, CMD with muscle hypertrophy, CMD with muscle hypertrophy and respiratory failure, CMD with myasthenic syndrome, and Ullrich CMD.^[4]

Ullrich CMD

Present at birth is weakness, poor muscle tone, will have some deformity and rigidity joints, some joints will have excessive flexibility, spinal rigidity, curvature, respiratory impairment, soft skin, normal cardiac function and normal intelligence.^[4]

See also

muscular dystrophies

Ullrich Congenital Muscular Dystrophy

Fukuyama Congenital Muscular Dystrophy

Stories of families trying to deal with their child that has Congenital Muscular Dystrophy:

1. High-risk world of rare genetic diseases: Research efforts improving
2. Mum tries to raise $30k to give son Fletcher hope of recovery from congenital muscular dystrophy

References

1. ↑ Mercuri, Eugenio; Sewry, Caroline; Brown, Susan C.; Muntoni, Francesco (2002-01-01). "Congenital muscular dystrophies". Seminars in Pediatric Neurology 9 (2). doi:10.1053/spen.2002.33802. 
2. ↑ Klein, Andrea; Clement, Emma; Mercuri, Eugenio; Muntoni, Francesco (2008-01-01). "Differential diagnosis of congenital muscular dystrophies". European Journal of Paediatric Neurology 12 (5). doi:10.1016/j.ejpn.2007.10.002. 
3. ↑ "Types of CMD Chart Congenital Muscular Dystrophy". Muscular Dystrophy Association. Retrieved 2015-09-04. 
4. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 < "Types of CMD Chart Congenital Muscular Dystrophy". Muscular Dystrophy Association. Retrieved 2015-09-04.