Li yonglei
For "edema", most people will recognize it. The simplest way is to press the affected area with your hand. If the skin sags into a small pit and cannot recover immediately, it is "swollen". After living at home for more than two months, many middle-aged and elderly people have similar edema. What needs to be vigilant is that the causes of edema are not only the obvious reduction of exercise and the high age of the family, but also some pathological reasons may be hidden.
Clinically, "edema" generally refers to edema of lower limbs, mainly manifested as swelling of limbs, which starts at the ankle and then spreads to the whole lower limbs, and sometimes occurs in the limbs, but edema of lower limbs is the most common.
Why does kidney disease cause edema?
Mr. Ma has always felt weak waist recently, and his urine is dark and frothy. When he took off his socks, he found obvious indentation on his calf. After seeing a doctor, he was diagnosed with hematuria, proteinuria, moderate hypertension and other problems, and was later diagnosed as acute glomerulonephritis. The edema in the patient’s leg is the secondary edema caused by renal disease.
Edema can be caused by many reasons, and different edema has different characteristics. Edema caused by kidney diseases is called nephrogenic edema. Nephrogenic edema is the most common cause of edema in clinic, and it is also one of the common symptoms of kidney diseases. Why can kidney problems lead to edema? There are two main reasons: first, the filtration function of glomerulus to water and sodium decreases, while the renal tubule reabsorbs water and sodium well, which leads to the retention of water and sodium, which is often accompanied by the increase of capillary permeability in the whole body, so the water in the interstitial space is retained; Second, a large amount of proteinuria in the body leads to low plasma protein.
Nephrogenic edema first occurs in loose tissues, such as ankles, eyelids or face, which is most obvious in the morning and can spread to lower limbs and the whole body in severe cases. It is characterized by being soft and easy to move, showing concave edema in clinic, that is, depression can occur when pressing local skin with fingers.
Clinically, nephrogenic edema is mainly divided into nephrotic edema and nephritis edema.
Nephrotic edema mainly refers to nephrotic syndrome. In addition to systemic edema, patients also have a lot of proteinuria, hypoproteinemia and hyperlipidemia. All causes of nephrotic syndrome, including primary causes (minimal change nephropathy, mesangial proliferative glomerulonephritis, mesangial capillary glomerulonephritis, membranous nephropathy, focal segmental glomerulosclerosis) and secondary causes (allergic purpura, systemic lupus erythematosus, hepatitis B virus-associated nephritis, diabetic nephropathy, renal amyloidosis, myeloma nephropathy) can cause nephrotic edema.
Nephritis edema mostly starts from eyelid and face, mainly seen in patients with acute glomerulonephritis. In addition to edema and hypertension, the patient’s clinical manifestations are also urine changes, such as hematuria, proteinuria, red blood cell cast, oliguria, etc. After the acute phase, the edema can subside.
For such patients, early treatment is the key, and the overall treatment principles are as follows:
1. Restrict sodium salt intake: Both nephrotic edema and nephritis edema have sodium and water retention, so sodium salt intake must be restricted, but it should be appropriate to avoid hyponatremia;
2, diuresis: when necessary, using diuretics while limiting sodium can promote sodium and water discharge to relieve edema, and can relieve hypertension and reduce heart load;
3, control proteinuria: proteinuria must be controlled for nephrotic edema, and immunosuppressive drugs (dexamethasone, prednisone, etc.) can be used to restore the normal permeability of glomerulus;
4, under the guidance of a doctor, supplement plasma protein.
Some edema comes from heart disease.
Ms. Liu, 75, has a history of hypertension for many years, but she believes that she is in good health and does not take medicine regularly. After catching a cold two weeks ago, I felt weak, palpitation, obvious swelling of my feet, and it was difficult to wear shoes. After coming to the hospital, he was diagnosed as hypertension, coronary heart disease and heart failure by the Department of Cardiology.
Ms. Liu, a patient with hypertension, suffered from heart disease and heart failure after catching a cold. It is due to the edema of lung congestion tissue, the increase of airway resistance and the decrease of alveolar elasticity, resulting in dyspnea, which is to say that breathing is fast and shallow. In fact, clinically, most hypertension will be combined with various types of heart disease, and at the same time, different stages of heart disease may be accompanied by different degrees of hypertension. Poor long-term control of hypertension can cause changes in heart structure and function, which is called hypertensive heart disease. Studies have shown that 70% of heart failure is caused by hypertension, and there may be related cardiac complications such as coronary heart disease and atrial fibrillation. In the early days, patients are prone to fatigue dyspnea, such as when going upstairs, carrying loads, buying food, and even when looking after children. Some people will have paroxysmal dyspnea at night, which usually occurs 1-2 hours after falling asleep. Patients wake up because of tightness and shortness of breath, and may have cough and foam-like sputum. Those with mild symptoms can relieve themselves and live as usual during the day, while those with severe symptoms can continue to attack and cough pink foam-like sputum.
Then, how is edema related to high blood pressure and heart disease?
Recently, many patients who came to the hospital due to edema of lower limbs were admitted to the clinic, and some of them were diagnosed as cardiogenic edema. Cardiogenic edema is the body edema caused by cardiac dysfunction. The disease can present systemic or localized edema, which first manifests as decreased urine volume, heavy limbs and increased weight, and then gradually appears edema of lower limbs and whole body. Under normal circumstances, the patient’s ankle first appears sunken edema, which gradually develops into systemic edema. Accompanied by right heart failure, patients will also have other symptoms and signs, such as palpitation, asthma, jugular vein distension, hepatomegaly, and even pleural effusion and ascites. The principles of treating cardiogenic edema are cardiotonic, diuretic and heart protection.
In heart diseases, heart failure is the most common cause of limb edema. Due to the different concentrations of protein and salt in blood and surrounding tissues, when blood circulation is blocked, the surrounding tissues can easily absorb the liquid in blood excessively, resulting in edema. However, leg swelling caused by heart disease develops relatively slowly, and many elderly people only notice the abnormality because their feet are swollen and they can’t wear shoes. Cardiogenic edema of lower limbs does not need deliberate treatment, and the heart function is restored, and the symptoms of edema can naturally be significantly improved.
Mosquito bites can also cause edema of lower limbs.
Recently, Mr. Wang was bitten by a bug when he went out for an outing. After scratching his calf wound, he developed redness and edema. He was diagnosed with erysipelas after seeing a doctor.
Erysipelas is an infection involving superficial lymphatic vessels of dermis, and the main pathogenic bacteria are group A β Streptococcus hemolyticus Any inflammation of the skin, especially the inflammation with chapped or ulcerated skin, can be a way for pathogenic bacteria to invade the human body. Mild abrasions or scratches, injuries outside the head, unclean umbilical cord ligation and chronic leg ulcers may all lead to this disease.
Infected with erysipelas, why does the lymphatic system have edema?
Lymphatic system is a resource recovery and antivirus system of human body, which is widely distributed in human body. Lymphogenic edema mainly refers to the proliferation of subcutaneous fibrous connective tissue after repeated infection of soft tissue fluid on the body surface caused by the obstruction of lymph reflux in some parts of the body. If limbs are involved, it will be thickened, and the skin will be thickened, rough and tough like elephant skin in the later stage, also known as "elephant skin swelling".
Lymphatic dysplasia or infection can cause swelling of tissues in the corresponding area. There are also some people who have slight abnormalities in the development of blood vessels in their lower limbs and are more prone to edema symptoms. We usually analyze the condition of patients’ lymphatic system by puncturing subcutaneous edema tissue fluid. The protein content of lymphedema fluid is usually very high, ranging from 1.0 to 5.5g/dl, while the protein content of edema tissue fluid with simple venous stasis, heart failure or hypoproteinemia is 0.1 to 0.9g/dl. However, this method can’t understand the lesion site and function of lymphatic vessels, and it is necessary to determine the development or obstruction of lymphatic vessels by lymphangiography.
Thromboedema of cardiac vein in patients with low back pain
Mr. Liu is obese, has irregular meals and stays up late for a long time. He is a lover of carbonated drinks and has a history of lumbar muscle strain and lumbar disc herniation. In recent days, he suffered from swelling and pain in his unilateral calf, which was obvious after sitting and standing, but did not relieve obviously after lying in bed. After examination by a doctor, deep venous thrombosis has formed in his lower limbs.
Seeing the doctor’s diagnosis, Mr. Liu was puzzled and felt that the thrombus came suddenly. Actually, it is not. He is obese, does little exercise, stays up late, and has an unreasonable diet. These factors will easily lead to an increase in blood viscosity. In addition, he suffers from waist disease, and will stay in bed and take medicine when the pain attacks. Staying in bed for a long time will make the blood flow slow, the muscles will not pump enough blood, and it is easy to form a thrombus. At the same time, although taking medicine relieved waist inflammation, it also concealed other symptoms, thus delaying the opportunity to see a doctor. Therefore, we remind patients with lumbar diseases to pay attention to the phenomenon of edema in limbs.
Venous thromboedema is common after surgery, trauma, long-term bed rest and long-term desk workers. The vast majority of venous thrombosis of lower limbs is painful first and then swollen, and the more swollen it is, the more painful it is. The most common harm of this disease to human body is pulmonary embolism caused by blood clots falling off, which leads to death. Some blood clots may also cause cerebral thrombosis, renal thrombosis and intestinal thrombosis. The degree of harm mainly depends on the proportion of blood vessel blockage and the shape of thrombus. After regular anticoagulation and anti-inflammatory treatment, a considerable number of patients’ conditions can be stable, and regular medication can be taken later. For those with serious blood vessel blockage and the risk of thrombus falling off, timely surgery is needed. At present, the implantation of inferior vena cava filter is the main method to prevent fatal pulmonary embolism caused by thrombus shedding in acute stage, and it is a minimally invasive operation by interventional method. If thrombus is ablated after anticoagulant therapy, surgery can be avoided; If the patient has persistent high fever, sepsis, uncontrollable infection and irreversible necrosis of lower limbs, it may be necessary to consider amputation.
Generally speaking, there are many reasons for edema of lower limbs, which cannot be enumerated here. For healthy people, we suggest that you do the following three things in your daily life to avoid edema as much as possible. First, exercise moderately, avoid sitting and lying for a long time, and pay attention to moving the lower limbs when flying for a long time; The second is to supplement water properly and eat fruits and vegetables reasonably to avoid blood viscosity; Third, those who suffer from physical injuries due to diseases or various reasons, and need to use anti-inflammatory and anticoagulant drugs for prevention under the guidance of professional doctors, should follow the doctor’s advice and take drugs correctly.
(Author: Beijing Longfu Hospital)
