Thymus hypertrophy

Introduction On the upper edge of the human sternum, there is an organ that is only 10 grams in weight - the thymus. The T cells produced by the bone marrow only enter the thymus with the blood and are affected by thymus hormones. Finally, about 5% of the thymocytes develop into mature T lymphocytes with immune function.

Cause

Cause

The thymus is the largest in a year after birth, and gradually degenerates after puberty. Its volume is reduced by about 3% per year and continues into middle age. After entering the old age, the thymus tissue is atrophied, and most of it is replaced by adipose tissue. The number of cells is greatly reduced, and the concentration of thymus hormone in the blood is significantly decreased. Therefore, the immune function of the elderly is significantly reduced compared with that of the young, and various infections are prone to occur. Sexual diseases, autoimmune diseases and tumors.

an examination

Related inspection

Chest radiography CT examination dynamic electrocardiogram (Holter monitoring)

1. Chest X-ray examination: It shows a substantial block shadow of the anterior mediastinum, slightly lobulated, and occasionally punctate calcification in the substantial block. Most asymptomatic thymoid cancer patients are found by chest X-ray.

2. Chest CT scan: It is an important means to diagnose thymic carcinoid. It can clearly show the shape of the tumor itself and the infiltration of adjacent organs. In particular, enhanced CT can clearly show the condition of invasion of the superior vena cava, and provide important reference value for the choice of surgical plan. When clinical manifestations of ectopic ACTH syndrome appear, but because of the small chest X-ray examination can not be clearly diagnosed, CT scans can often find smaller thymoid carcinoid lesions, so that the diagnosis is clear. Brown (1982) reported that 4 patients with clinically diagnosed ectopic ACTH syndrome and no chest X-ray findings were found to have anterior mediastinal tumors by CT and finally confirmed by surgery as thymic carcinoid. Jex (1985) reported that 25 cases of Cushing's syndrome caused by ectopic adrenocortical hormone-secreting tumors, 2 cases of thymic carcinoid tumors were detected by chest CT scan, and confirmed by surgery.

3. Bone radionuclide scanning: When the diagnosis is confirmed (surgical resection or biopsy), bone radionuclide scanning should be performed routinely. Because about 1/3 of cases of thymic carcinoid tumors may have bone metastases.

Differential diagnosis

Differential diagnosis of thymus atrophy:

Absence of thymus: it is a clinical manifestation of congenital thymic hypoplasia. Congenital thymic hypoplasia is also known as DiGeorge syndrome or the third and fourth pairs of pharyngeal sac syndrome. It is a congenital immune deficiency caused by abnormalities of the pharyngeal sacs in the first to sixth stages of the embryo.

Atrophy of the vocal cords: the vocal cord's own tissue and the muscles of the vocal cords are atrophied. Once the vocal cords are atrophied, the vocal cords are easy to close when we are vocalizing. So the patient can easily feel that the speech is very tired and the sound will be hoarse. This in turn leads to the inability of the patient to achieve a high and low level when working and singing.

Muscle atrophy refers to the reduction of muscle volume caused by dystrophic dystrophy, muscle fiber thinning or even disappearance. Muscle atrophy is often accompanied by low muscle strength, so you should pay attention to the comparison of muscle volume and muscle strength, pay attention to muscle strength and muscle tension in muscle atrophy. The inspection should be carried out in a warm environment and in a comfortable position. Patients should be allowed to relax as much as possible. It can be judged by touching the hardness of the muscle and the resistance that is felt when the patient's limb is flexibly flexed. When the muscle tension is reduced, the muscles are slack, the resistance is reduced or disappeared during passive exercise, and the range of motion of the joint is enlarged. More common in lower motor neuron lesions, some myopathy such as disuse muscle atrophy.

The sternocleidomastoid and trapezius tendon are atrophied: the injury of the spinal nerve branch of one side of the accessory nerve or the damage of the spinal cord, the ipsilateral sternocleidomastoid and the trapezius tendon, and atrophy, due to the contralateral side The sternocleidomastoid is dominant, so when it is calm, the chin is turned to the affected side, and when it is forced, it is weak to the contralateral side, the affected side is drooping, the shoulder cannot be shrug, the shoulder blade is skewed, and the muscles it swells due to the shoulder blade. Displacement causes the brachial plexus to undergo chronic traction, which limits the lifting and abduction of the upper limb of the affected side. In the late stage, due to scar stimulation, a hernia contraction (rose neck) deformity can occur. When bilateral damage occurs, the patient's head and neck are reclined and front. Paralysis, paracranial fractures or gunshot wounds caused by accessory nerve injury, jugular vein hole lesions, occipital macropore lesions, cerebral cerebral horn angle lesions and subcranial lesions caused by paraneoplastic lesions and medullary nucleus often The posterior group of cranial nerves and other cranial nerve lesions appear at the same time, while in the brainstem nuclear paralysis, the damage of the cranial nerves is often more and bilateral.

The material in this site is intended to be of general informational use and is not intended to constitute medical advice, probable diagnosis, or recommended treatments.