This is a procedure in which muscle tissue is removed from an organism and examined microscopically. Muscle biopsies can distinguish between Myopathies, (the pathology is in the muscle tissue itself) and neuropathies (pathology is at the nerves innervating those muscles) by means of microscopic analysis. Problems could be detected in a nervous system, in connective tissue, vascular or musculoskeletal system. A variety of Myopathies can cause centronuclear biopsy and hence a specific genetic testing becomes increasingly important.
What is muscle biopsy?
This is a procedure when a small sample of tissue is removed for testing in a laboratory. The test detects an infection or disease in the muscles. This is a relatively simple procedure. It is done as an outpatient basis, and the patient is free to leave on the same day as the procedure. As it is often done on a local anesthesia, the doctor removes the tissue from the area but the patient remains awake for the test.
Reasons for a muscle biopsy
This is done when the doctor suspects an infection in the muscle. The biopsy is done to help the doctor rule out certain conditions that could cause the symptoms and then proceed with an appropriate treatment plan.
Risks of a muscle biopsy
There is always a risk of infection or bleeding or bruising possible when a medical procedure that breaks the skin is performed. However, since the incision here is quite small, especially in needle biopsy, the risk is much lower. An electromyography is done in case of recent muscle damage. Very rarely there could be damage to the muscle where the needle is inserted.
Muscle biopsy procedure
There are two ways in which muscle biopsies are performed - the common method is called a needle biopsy and for this procedure, the doctor inserts a thin needle through the skin and remove the muscle tissue. This could be:
Core needle biopsy with a medium sized needle, similar to the way core samples are taken from the earth
Fine needle biopsy using a thin needle attached to a syringe, fluids and cells are drawn out.
Image-guided biopsy where the needle biopsy is guided with imaging procedure; such as x rays and CT scans.
Vacuum assisted biopsy uses suction from a vacuum to collect more cells.
The patient receives a needle biopsy after a local anesthesia and will not feel any pain or discomfort. There will be pressure in the area where the biopsy is taken and the area may be sore for about a week. In case the muscle sample is far to reach and is in deep muscles, the doctor may choose to perform an open biopsy. The doctor will make a small cut in the skin and then remove the muscle tissue from there.
For instance, if patient needs have a biopsy in the leg, he/she must expect to use crutches or another assistive device for two full days after biopsy. Training with crutches is provided. Some patients may need assistance at home during the recuperation period. If patients have had a biopsy in the arm, they must expect to wear a sling for two days. Stitches do not need to be removed but must remain completely dry for a couple of days.
In general, there are few complications and the resulting scar heals well. After the tissue sample is taken, it is sent to a laboratory for testing and the results would be ready in a couple of week's time. A report on frozen or paraffin specimens will be sent to the referring physician. The small piece of muscle tissue is examined by microscopic techniques to check for presence of fibrous tissue or other abnormalities. The extracted tissue can also be stained for detecting absence of presence of particular proteins. Microscopic examination can also reveal if the muscle fibers are being infiltrated by the immune system.
In case the results are abnormal, it could mean there is an infection or disease in the muscles and this may cause them to weaken or die. The doctor may prescribe additional tests to confirm the diagnosis and how far the condition has gone. Treatment options are discussed and further steps taken.
Myotonia Congenita is a neuromuscular genetic disease that involves progressive muscle stiffness and enlargement. This rare disorder is characterized by bouts of sustained muscle stiffness or Myotonia. The resultant muscle tensing can range from mild to severe. Myotonia Congenita occurs due to mutation of the CLCNI gene. This gene is critical in the functioning of the skeletal muscles. Therefore the mutation leads to bouts of muscle weakness. Abnormal muscle enlargement or hypertrophy is noticed in persons suffering Myotonia, even in children.
Myotonia can affect muscles in any part of the body. In some it can affect the limbs. Some persons experience difficulty in swallowing or inability to relax their muscles quickly after contraction. Other symptoms include shortness of breath at the beginning of exercise.
Thomsen disease: In this form of the disorder, the symptoms manifest early in infancy. The main characteristic symptom of Thomsen disease is muscle stiffness or even muscle weakness after a bout of strenuous exercise. Even stress, fatigue or cold can act as triggers. The symptoms become noticeable in 2-3 years. Limbs and eyelid muscles are often affected. Thomsen disease is transmitted as an autosomal dominant trait.
Becker disease: This form of the disorder typically occurs later in life. The symptoms of Becker disease are noticed between 4-12 years. In Becker Myotonia, there is severe muscle stiffness which can often lead to mild muscle atrophy. Some medications such as beta blockers, diuretics and muscle relaxants can trigger Becker disease symptoms. Becker disease is inherited as an autosomal recessive trait.
An Electromyography is done to test the electrical activity within the muscles. Muscle biopsy is performed to check for absence of 2B fibers. CK blood test is done to check for elevated creatine kinase levels.
Myotonia Congenita Treatment
In the absence of a cure for Myotonia Congenita, a holistic approach encompassing lifestyle changes, physical therapy, and avoiding triggers is effective. Termed as the warm-up phenomenon, for most people regular exercise has been effective to relax the stiff muscles. Healthcare providers suggest making lifestyle modifications such as avoiding certain situations and physical therapy even before prescribing medications. Rehabilitative therapy to improve muscle function and relaxation techniques to reduce stress and mental discomfort which may worsen the disorder is also recommended.
Only when all these are insufficient, medications such as quinine and anticonvulsant drug such as phenytoin are prescribed. Children diagnosed with the disorder should have regular consultation with pediatric neurologist to understand and manage the disorder with the least disturbance during the growing years. Custom designed exercises, selecting suitable games and sports, avoiding foods that trigger lets children work around the symptoms and have a quality life.
Becker muscular dystrophy
Becker muscular dystrophy or BMD is one of the nine types of muscular dystrophies characterized by muscle wasting and weakness which is mainly proximal. it is caused by mutations in the same genes as is the case with Duchenne muscular dystrophy. Becker muscular dystrophy is also caused by a mutation of the dystrophin gene, which is responsible for the body to make the protein dystrophin, that is essential for normal muscle function. However, BMD is less severe and is slow in its progression and generally, walking difficulties begin after the age of 16. Becker muscular dystrophy affects only boys and young men, and women are generally only the carriers of the mutated gene.
Symptoms of BMD
Becker muscular dystrophy affects the muscles of the hips, pelvic area, thighs and shoulders, as well as the heart. The symptoms typically start to surface during adolescence and become clearly noticeable by the time the child reaches his mid teens. The health of the patient worsens over time and shortens his life expectancy. The majority of people diagnosed with BMD do not survive beyond 40 or 50 years.
Some of the symptoms include:
Diagnosis and treatment
The following are some of the diagnostic tests conducted before confirming the Becker muscular atrophy. Serum test for assessing creatine kinase as raised CK levels call for further investigation.
Treatment of BMD
There is no permanent cure for any muscular dystrophy. Becker muscular dystrophy needs to be managed according to the particular symptoms of each patient. The main aim of the treatment is to optimize the muscle functioning and increase the quality of the life. Physiotherapy, steroid medications, orthopaedic aids such as splints, braces, and genetic counseling go a long way in giving support to the patient.
Bibliography / Reference
Collection of Pages - Last revised Date: May 24, 2018