Nemaline myopathy

 nemaline myopathy (MN), also called myopathy nemaline myopathy stick or cane, refers to a group of neuromuscular disorders of genetic etiology, characterized by leads to muscle weakness.

Muscle weakness is present in this disorder resulting from the accumulation of corpuscles bastonetiformes (linear rods) in muscle fibers, especially in the periphery of the latter.

To date, five mutations have been identified in different genes, leading to the presence of linear rods in the muscle fibers. Genes are: ACTA1, MEN2, TPM3, TPM2 eTNNT1.

This disease was first identified in 1958 by Australian physician Douglas Reye. However, the study by this doctor was never published because another colleague of his profession believed that bats found in linear muscle fibers treated to actually fault biopsy. Only forty years later was that it was confirmed the diagnosis of nemaline myopathy in patients studied by Dr. Reye.

Clinically, this disease can be classified as mild (mild), moderate, severe (severe) or late. However, this distinction is often blurred and difficult.

The main clinical manifestation of this pathology is the weakness of the proximal muscles, especially of the respiratory muscles. Individuals who have a severe picture of MN are affected by this symptom from birth, whereas in mild or moderate cases, the principle carriers appear to be healthy. Babies with this condition have hypotonia, while adults have a slender body and characteristic.

Although children with this condition can walk, start walking late when compared to other children. Carriers severe form of MN movements typically have limitations and need a wheelchair full time. As a result of muscle weakness, these patients are more likely to develop scoliosis. Furthermore, it is common for such individuals present osteoporosis.

Respiratory problems are a major concern in patients with MN. Babies with a severe form of the disease have difficulty breathing during or soon after birth. However, patients with mild and moderate form of MN does not have respiratory compromise so apparent.

Swallowing problems are also common, once the weakness of the muscles of the neck is usually part of the MN. Individuals who have a severe form of the disease are unable to swallow food. Who has already mild to moderate forms commonly receive most or all meals by mouth.

Diagnosis and Treatment

The diagnosis is usually achieved through a muscle biopsy, with subsequent histological analysis of the material, which is observed a distinct pattern of structures, the corpuscles bastonetiformes. However, these structures can also be found in other related conditions is important, therefore, to correlate the biopsy with the history, clinical picture presented by the patient and / or molecular tests for the MN.

Although there is no cure for this disease yet no way to stop its progression, symptomatic treatment is important to prolong the life of patients and involves the MN:

Night ventilation;

Feeding tube;

Physiotherapy;

Speech;

Physical activity;

Antibiotics since they are frequent lung infections in patients with MN.