Infantile Spinal Muscular Atrophy

Definition

Definition of Infantile Spinal Muscular Atrophy
The spinal muscular atrophies (SMAs) comprise a group of autosomal-recessive disorders characterized by progressive weakness of the lower motor neurons. In the early 1980s, Werdnig and Hoffman described a disorder of progressive muscular weakness beginning in infancy that resulted in early death, though the age of death was variable. In pathologic terms, the disease was characterized by loss of anterior horn cells. The central role of lower motor neuron degeneration was confirmed in subsequent pathologic studies demonstrating a loss of anterior horn cells in the spinal cord and cranial nerve nuclei.

Symptoms

Symptoms of Infantile Spinal Muscular Atrophy
Infantile SMA is the most severe form. The symptoms include:

1. Muscle weakness
2. Poor muscle tone
3. Weak cry
4. Limpness or a tendency to flop
5. The legs tend to be weaker than the arms
6. Feeding difficulties
7. Increased susceptibility to respiratory tract infections
8. Developmental milestones, such as lifting the head or sitting up, can’t be reached.

Causes

Causes of Infantile Spinal Muscular Atrophy
Infantile SMA is caused by a faulty gene. If a couple already has a child with the disorder, each of their subsequent children has a 25 per cent chance of inheriting the disorder too. Genetic counselling is available for these couples.

Diagnosis

Diagnosis of Infantile Spinal Muscular Atrophy
Consult with your doctor.

Treatment

Treatment of Infantile Spinal Muscular Atrophy
Infantile SMA is a fatal disorder and there is no cure. Treatment can only ease any associated complications. For instance, since a child with infantile SMA is prone to respiratory infections and pneumonia, treatment focuses on trying to maintain the child’s lung function and health. Usually, a team of professionals - paediatricians, physiotherapists, neurologists, and respiratory physicians and therapists - work together to help improve the child’s quality of life.

Prognosis

Prognosis of Infantile Spinal Muscular Atrophy
A child with infantile SMA is prone to respiratory infections. Pneumonia is a type of lung infection where the smallest airways, called the alveoli, are blocked with mucus and secretions. In healthy people, pneumonia can be simply treated with antibiotics. However, a child with infantile SMA is already in a weakened and vulnerable state. Pneumonia is the cause of death in the majority of cases.

Prevention

Prevention of Infantile Spinal Muscular Atrophy
Consult with your doctor.