Spinal muscular atrophy

Generally speaking, this disease is a recessive genetic disease. Many people may not have heard of the dangers of this disease, but this disease exists in our lives and can cause great harm to the human body. If this disease occurs in a woman, the diseased area may be in the uterus, which will not only have a certain impact on fertility but also endanger health.

The more common symptoms of this disease actually appear in childhood, such as developmental delay. There is currently no effective treatment for this disease, but family members must support and encourage the patients.

symptom

1. SMA-Ⅰ is also called Werdnig-Hoffmann disease. About one-third of cases develop in utero, with the mother noticing a weakening of fetal movements. Half of the cases develop the disease within 1 month of birth, and almost all cases develop within 5 months. The incidence rate is about 1/10,000 live births, with equal incidence in males and females. Most children show signs of hypotonia shortly after birth, with muscle weakness mainly affecting the proximal muscles of the limbs, and trunk muscles also being weak. The child has weak sucking and swallowing ability, soft crying, shallow breathing, and may have abnormal chest movement. Difficulty turning over and raising the head. Tendon reflexes are absent. Palpation may reveal muscle atrophy in the limbs, but it is often concealed by subcutaneous fat. Eye movements were normal. The sphincter function is normal. Tongue muscle atrophy and fasciculations may be seen. Joint deformity or contracture may occur in 10% of cases. This type has a poor prognosis. About 95% die within the first 18 months of life.

2. The onset of SMA-II is slightly later than that of SMA-I, usually within 1 year old, and rarely between 1 and 2 years old. The incidence is similar to that of SMA-Ⅰ. The baby's early growth was normal, but his motor development was delayed after 6 months. Although he could sit, he could not stand alone or walk at normal levels. More than 1/3 of the children are unable to walk. 20% to 40% of children are still able to walk before the age of 10. Most cases present with severe proximal limb muscle weakness, which is more severe in the lower limbs than in the upper limbs, while the respiratory and swallowing muscles are generally not affected. Facial muscles are affected in 1/3 of cases. Tongue and other muscle fibrillations can be seen in more than 50% of cases. Tendon reflexes are weakened or absent. This type has a relatively benign course, with most patients surviving into childhood and a few into adulthood.

3. SMA type III is also known as Kugelberg-Welander disease. The disease usually begins during early childhood to adolescence, and most cases begin before the age of 5. Onset is insidious, with progressive proximal limb weakness and atrophy. In the early stages, thigh and hip muscle weakness is more pronounced, causing the child to walk like a duck and have difficulty climbing stairs, and gradually the shoulder girdle and upper limb muscles are affected. Muscles innervated by cranial nerves are usually not affected, but facial and soft palate muscles may become weak. Extraocular muscles were normal. About 1/4 of cases are accompanied by pseudohypertrophy of the gastrocnemius muscle, which is almost always seen in male patients. Fasciculations were seen in half of the patients in the early stages. Cavus feet may also be seen. Tendon reflexes are weakened or absent. Feeling normal. This type has a good prognosis, especially in female patients. Survival is usually into adulthood, and many affected individuals have a normal life span. More severe cases tend to occur in male patients. In this type of disease, serum CPK may be elevated to varying degrees. In addition to neurogenic changes, EMG may also be mixed with myogenic damage, so care must be taken to differentiate it from muscular dystrophy.

4. SMA-IV type is collectively referred to as adult-type SMA. The age of onset ranges from 15 to 60 years old, most commonly around 35 years old. The onset and progression are relatively insidious, but there are also reports of cases showing progressive worsening or relative quiescence. The prognosis of this type is relatively good, and the ability to walk can often be maintained throughout life. The incidence rate is less than 0.5/100,000. About 1/3 of cases of this type are inherited in an autosomal dominant manner, characterized by proximal muscle weakness that progresses slightly faster and leads to loss of the ability to run after about 5 years. There is also an autosomal recessive form, which generally has a more benign course. The other type is X-linked recessive inheritance, also known as spinal cord brainstem SMA (Kennedy disease). The age of onset varies, but it usually occurs before the age of 40. Early symptoms include painful muscle cramps, which may precede muscle weakness by several years. Proximal muscle weakness often starts from the lower limbs and gradually spreads to the shoulder girdle muscles, facial muscles and muscles controlled by the medulla oblongata. Fasciations may be seen in the inferior and lingual muscles. After several years, dysphagia and indigestion may occur. About 50% of cases are associated with some endocrine dysfunction, manifested as male breast feminization and primary testicular lesions.

The above is an introduction to some symptoms of spinal muscular atrophy. I believe that after reading it, you will have a better understanding of the symptoms of this disease. When facing some diseases, you may seem helpless, but you must know how to persevere and face the disease with a positive attitude.