Simple renal cyst is one of the most common and symptoms lightest in polycystic kidney disease, common in adults over the age of 50 and is rare in children, so it may be acquired. Can be isolated or multiple, more common in men and left kidney, often unilateral onset, can also merge contralateral renal disease.
(1) the cause of the disease
It can be caused by structural changes of congenital glomerulus and renal tubule, and can also be caused by acquired injury, infection and so on.
Simple renal cyst pathogenesis has not been fully elucidated, although belong to non hereditary diseases, but Schnlzinger (1994) found two simple renal cyst family, gene linkage analysis of it has not been found with autosomal dominant polycystic kidney disease (ADPKD), that there may be autosomal dominant pure renal cyst. The lesions were more common in the renal lower pole. Cysts originate in the renal tubules and protrude on the surface of the renal cortex, which is blue in appearance and located in the deep cortex or medulla. General diameter of less than 1cm, can also have 3 ~ 4cm, inpidual up to 10cm or above. Capsule contains sterile clear amber liquid, and 5% is bloody liquid. Among them, about 1/3 to 1/2 cases have cystic wall malignant lesions. The capsule is thin, lined with a single layer of squamous epithelium, and has fibrosis and calcification in an egg like manner. Lower cyst can cause ureter obstruction, hydronephrosis and infection.
Simple renal cysts usually occur in adulthood, usually without clinical symptoms, without affecting renal function, and occasionally due to hematuria. The vast majority of patients were incidentally discovered during type B ultrasound or CT examination. Urinalysis is normal and hematuria is rare. But kidney cyst can cause abdominal pain and abdominal mass, high blood pressure, such as cyst broken into the pelvis, renal calyx system, can have hematuria. Cysts can also cause obstruction of the renal pelvis and renal pelvis.
According to the clinical manifestations of hypertension, renal obstruction caused by secondary urinary tract infection, and B ultrasound, CT and MRI, the renal cyst fluid examination, and the exclusion of other types of renal cystic disease, can make the disease diagnosis. The diagnosis of this disease mainly depends on type B ultrasonography or CT examination.
Urine test for infected patients can have pyuria, hematuria, but without renal insufficiency.
1. imaging examination
(1) B ultrasonic examination is the preferred method. The typical B-mode ultrasonography showed no echo in the lesion area. The wall of the capsule was smooth and the border was clear. When the wall showed irregular echo or localized echo enhancement, we should be aware of malignant lesions. The secondary infection was thickened and the lesion had fine echo. The echo enhanced with bloody fluid.
(2) CT is valuable to B ultrasound examination. Cysts with bleeding or infection present an inhomogeneity and CT level increase. When CT is shown to be cystic, there is no need to make a diagnostic biopsy.
(3) IVU can show the extent of cystic compression of the renal parenchyma or ureter.
(4) MRI can help determine the nature of fluid sacs.
2. cyst puncture and cystic fluid examination, when B ultrasound, CT cannot diagnose or suspect has the malignant pathological change, may carry on the cyst puncture under the B ultrasound guidance, extracts the cyst fluid test. Cysts secondary to the tumor, the capsule is bloody or dark brown, fat and other components increased significantly, cytology positive, tumor markers CA-50 levels increased. In the combined infection, the cyst was dark and cloudy, the content of fat and protein increased moderately, amylase and LDH increased significantly, inflammatory cells were detected by cytology, and the pathogen could be determined by cyst fluid culture. After the extraction of the cyst fluid, the contrast medium and (or) gas are added to display the wall of the cyst. If the wall of the capsule is smooth, no tumor is present.
Since simple renal cysts develop slowly and do not necessarily damage the kidneys, and when found most patients are older and have tended to be conservative in treatment in recent years.
1. without renal parenchyma or renal pelvis and renal pelvis obvious pressure, no infection, malignant change, high blood pressure or the above symptoms are not obvious, even if the cyst is larger, also does not advocate surgery, and should take B ultrasonic examination, close follow-up.
2. when the secondary infection, in view of the antibiotic can penetrate the cyst wall, into the cavity, can first be treated with antibiotics and ultrasound guided puncture drainage. When failure is invalid, open surgery is considered.
3. if the cyst is confirmed canceration or accompanied by kidney cancer, it should be treated as soon as possible.
4. cyst diameter is greater than 4cm, feasible puncture and sclerosis treatment, the choice of hardener should be careful. Tetracycline has the dual effect of hardening and preventing infection, with a curative effect of 96% and little side effect. Bismuth phosphate was also effective, 44% cyst disappeared completely, 52% reduction, no serious complications.
5. when the above treatment is invalid and the symptoms or cysts are obviously infected, the feasible cyst unroofing or partial nephrectomy is performed.
6. if the cyst causes serious renal infection, the renal function has been seriously damaged, while the contralateral renal function is normal, nephrectomy can be performed.
For the treatment of simple renal cyst, the effect of cyst on the kidney and the whole body should be considered comprehensively, depending on the development of the cyst. If the above situation is not obvious, we should closely follow up observation, do not rush treatment.
The disease usually has no clinical symptoms, does not affect renal function, so the prognosis is good, and it does not affect the patient's life.
Because there is no effective treatment, prevention and treatment of renal complications and maintenance of renal function is the main purpose of prevention.
The patient should avoid close contact activities, especially collision and compression, in case of cyst rupture.
The patient is prone to urinary tract infections, especially in women, and must be actively symptomatic and supportive treatment.
1. hydronephrosis, when Hydronephrosis serious can involve soreness of the lumbar region and cystic mass in the abdomen and abdomen. However, IVU and retrograde pyelography showed enlargement of the renal pelvis and renal pelvis. B-mode ultrasonography and CT examination showed that the central renal parenchymal area was thinner and the renal parenchyma became thinner.
2. renal cystic perticulum, can be detected by B ultrasonography. Excretory urography showed perticulum with contrast agent, but can not display the perticulum and pelvis or kidney communicated with the channel, the channel of the developing feasible retrograde pyelography. Occasionally there is stone shadow in perticulum.
3. multilocular cystic renal cyst, mainly characterized by abdominal discomfort, abdominal mass, and occasionally hematuria. B ultrasound and CT showed parenchymal cystic masses in the kidney. But the cysts are pided into multiple fluid areas.
4. kidney cystonephrosis, B ultrasound, IVU and CT showed similar changes in renal cyst. But the wall of the cyst is thicker and the inner wall is irregular. Renal arteriography revealed a dense proliferative vessel surrounding the renal parenchyma. Intraoperative frozen section is helpful for diagnosis.
5. kidney abscess, generally has acute infection of systemic manifestations, such as high fever, chills, etc., the side of the kidney pain, muscle tension, rib ribs angle obvious percussion pain. Leukocytosis, white blood cells in urine, and positive bacterial cultures. IVU shows renal pelvis, calyx, compression or filling defect. B ultrasound in liquid dark area and kidney area can cause pyonephrosis primary lesions. The pus can be withdrawn from the puncture.
The cyst is located at the renal hilum, which oppresses the renal artery and leads to an increase in plasma renin, which can lead to high blood pressure, or secondary infection with obstruction of the renal calyx.
Complications caused by simple renal cyst:
The cyst is located at the renal hilum, which oppresses the renal artery and leads to an increase in plasma renin, which can lead to hypertension, or secondary infection with the obstruction of the renal calyx, as specified below:
1, in case of not using antihypertensive drugs, blood pressure is more than 139mmHg and / or the diastolic pressure is more than 89mmHg, according to the blood pressure level of hypertension can be pided into 1, 2, 3. Systolic blood pressure more than 140mmHg and diastolic blood pressure <90mmHg as a single isolated systolic hypertension. The patient has a history of hypertension and is currently being treated with antihypertensive drugs. Although the blood pressure is lower than 140/90mmHg, it should be diagnosed with hypertension.
2, obstructive nephropathy refers to urinary tract, urine circulation disorders, resulting in backward pressure, affecting the normal physiological kidney parenchyma and lead to kidney disease. A complete and partial obstruction degree; the scope of bilateral and unilateral time; acute sudden and gradual occurrence; parts of the upper urinary tract and lower urinary tract; upper urinary tract at the connection point above the ureter bladder (ureter, renal pelvis, ureter and renal pelvis junction) is located in the lower urinary tract; the ureter bladder connection point (following the urethra, bladder neck, bladder and ureter junction). The influence of the kidney is related to the degree and time of obstruction. Early removal of the obstruction can make the lesion disappear, and last stage, the renal function is permanently lost and can not be reversed. Therefore, it is very important to recognize obstructive nephropathy and remove obstruction in time.
Dietary considerations for simple renal cysts:
1, appropriate food
Simple renal cyst should be eat light, digestible food, fresh vegetables and appropriate amount of fruit, proper drinking water. Pay attention to the balanced diet.
2, taboo food
Renal cyst should avoid eating spicy, such as pepper; avoid alcohol; smoking (including passive smoking); bogey chocolate; coffee, sea fish, shrimp, crab and other volatiles; avoid salty foods, especially pickled; avoid contaminated food such as unhealthy food, rotten and deteriorated leftovers, etc.; avoid barbecue food.
3, limit the use of food
(1), protein control: modern medicine believes that protein intake is too low or too much, no benefit to the kidneys. In particular, large amounts of protein can produce excessive metabolic products, such as uremic toxins, urea, creatinine, guanidine, polyamines, and certain middle molecular substances, essentially nitrogen (protein) metabolites. Controlling protein (low protein diet during renal failure) plays an important role in reducing the burden of the kidney, reducing the production of uremic toxins and alleviating the disease.
(2), salt intake restrictions: when control of salt, according to the patient's condition and the degree of renal function to adjust, but not all patients with chronic renal dysfunction should strictly limit the salt.
(3), water intake: simple renal cyst, the renal function of concentration decreased, metabolic products need more water can be discharged from the kidneys, so simple renal cyst patients without obvious edema, heart failure, hypertension, should not blindly limit water.