idiopathic retroperitoneal fibrosis

Introduction

Introduction to idiopathic retroperitoneal fibrosis Idiopathic retroperitoneal fibrosis (idiopathicretroperitoneal fibrosis) refers to the inflammatory reaction and fibrosis of the retroperitoneal connective tissue caused by different causes, forming dense fibrous tissue surrounding and compressing the organs behind the peritoneum (such as the ureter and adjacent large blood vessels) . Compression of the ureter can cause upper urinary tract obstruction, which can affect kidney function and lead to uremia. basic knowledge The proportion of illness: 0.0005% Susceptible people: no specific population Mode of infection: non-infectious Complications: Crohn's disease

Cause

Idiopathic retroperitoneal fibrosis

(1) Causes of the disease

The cause of this disease is unknown and may be related to the following factors:

1. Allergic theory: RPF is often accompanied by abdominal aortic aneurysm-like dilatation, severe aortic wall calcification, ureteral obstruction and peri-arterial inflammation. Recently, Bullock suggested that RPF is a thinning of the arterial wall from the atheromatous plaque. An allergic reaction caused by leakage of insoluble inflammatory fat, it should be renamed as "chronic peri-aortic inflammation", sometimes in macrophages and lymph nodes in atherosclerotic blood vessels and atherosclerotic plaques. An insoluble polymer of oxidized lipids and proteins was found. Immunohistochemical studies showed that the substance contained IgG and a small amount of IgM. This change may be the result of some autoimmune reaction, especially for steroid therapy. This argument can be confirmed.

2. Ergot compound theory: Graham reported that RPF occurred in 2 of the patients treated with ergometrine. Later, a group of 27 patients were treated with ergometrine for headache and RPF, and the drug was discontinued. Some cases returned to normal, the above phenomenon suggests that ergometrine has a causal relationship with RPF. On the contrary, Blandy et al said that the RPF patients reported in the UK have not taken this drug or any other ergot compound, and ergometrine is a kind of A serotonin blocker that increases endogenous serotonin levels by competitive inhibition of the receptor site, Graham suggested that serotonin can cause a carcinoid-like abnormal fibrotic response in susceptible patients. Bromocriptine is a derivative of ergot alkaloids, but it is not a serotonin blocker. It may also be associated with retroperitoneal and mediastinal fibrosis. It may be that ergot alkaloids cause sensitization or self as a hapten. Immune response, but so far there is no satisfactory evidence.

3. Other causes: Some people have suggested that RPF is associated with taking painkillers; some are suspected of beta-adrenergic blockers, but Pryor believes that this drug may have been used to treat hypertension caused by RPF. Not the cause of the disease.

The pathological feature is centered on the lower part of the abdominal aorta. There is a fine band of fibrous tissue extending around the common iliac vessels and extending to the inferior vena cava. The upper edge is usually below the renal artery, but fibrosis can occur. Around the thoracic aorta, it appears as a flat, solid gray-white fibrous plaque. The dividing line is usually clear and non-enveloped. When the lesion expands, the structure of the retroperitoneal space is surrounded, but does not invade these structures. The wall, typically the second bilateral ureter is surrounded.

Histological changes: There are varying degrees of inflammatory changes in the fibrous tissue, which seem to progress from the acute phase with a large number of lymphocytes, plasma cells and some eosinophils, small blood vessels, to the chronic phase with less cell and blood vessel relatives. Cooksey examined 10 surgical biopsy materials and concluded that the histological changes were not related to the disease stage, the edema of the ureteral tissue involved, the subepithelial subcutaneous (Suburothelial layey) lymphocytic infiltration, the myometrial fibrosis, and the calcifications in the fibrous tissue. The lymphatic vessels in the spots are all occluded, and the adjacent tissues are normal. The "blocking" of the ureters may be related to the loss of peristaltic function.

(two) pathogenesis

Almost all cases are in the final stage of the disease course, that is, ureter and large blood vessel obstruction. At this time, the lesion is flat and solid, and there is no gray-white fiber plaque on the membrane. It is densely adhered to the posterior mid-peritoneum. The thickness is usually several centimeters. The thickest can reach 12cm, the fibrous plaque has obvious edge, generally limited to the third lumbar vertebrae and the iliac crest, the two sides do not exceed 2cm outside the ureteral approach, the ureter, the lower aortic iliac artery and the inferior vena cava are fibrous tissue. Wrapped, a small number of lesions up to the kidney pedicle, even through the diaphragm to the mediastinum, into the pelvic cavity.

Another manifestation of retroperitoneal ureteral fibrosis is the fibrous tissue surrounding one or both sides, the middle ureter, while other parts are normal, microscopic changes are a subacute, non-specific, with varying degrees of fibrous adipose tissue inflammation With fibrous tissue as the main component with polynuclear leukocytes, lymphocytes, monocytes infiltration, interstitial accumulation of fat cells and sclerosing fatty granuloma, some areas have a particularly dense peritoneal fiber bundle, and glassy degeneration, lesions first Originated in the middle, around the large blood vessels, and later extended to the ureter on both sides, the wall is generally not significantly involved.

Prevention

Idiopathic retroperitoneal fibrosis prevention

Posterior peritoneal fibrosis is a disease with a certain degree of self-limiting and slow progress. Occasionally, the inflammatory process may spontaneously resolve. If the drug is caused by a drug (such as hydroxypropylmethyl lyseramide), it may gradually recover. The time varies from several months to several years, and the mortality rate of retroperitoneal fibrosis is about 9%. The cause of death is usually renal insufficiency, which often occurs due to delayed diagnosis. The prognosis is good when it is effective for proper treatment.

Complication

Idiopathic retroperitoneal fibrosis complications Complications Crohn's disease

The main complication of idiopathic retroperitoneal fibrosis is ureteral obstruction, which can be combined with sclerosing cholangitis, Reidel thyroiditis, Crohn's disease, arteritis and other systemic diseases.

Symptom

Idiopathic retroperitoneal fibrosis symptoms Common symptoms Post-peritoneal fibrosis Hypertension Menstruation ureteral stricture Anorexia ascites Nocturia increased back pain Portal hypertension High abdominal pain

The symptoms of this disease are closely related to the course of the disease.

The early symptoms of RPF are insidious, mainly characterized by non-specific back pain, abdominal pain and flank pain, persistent dull or dull pain, which can occur in any age and even newborns, but more common in middle-aged people, male patients are female 2 times, both Caucasians and blacks can get sick. Usually they are insidious and have a long course. The diagnosis is often made months or even years after some vague symptoms appear. The most common pain is usually the earliest symptoms. On the lateral side of the lower abdomen, the lumbosacral or lower abdomen feels blunt pain and discomfort. Other symptoms include anorexia, weight loss and fatigue. There may be swelling of one or both legs, swelling of the scrotum or moderate fever, and the abdomen or pelvic can touch the bag. Piece.

Clinical manifestations in the advanced stage are often symptoms of compression or involvement of adjacent organs, such as ureteral stricture can cause proximal infection or dilation, can produce lumbar or rib horn pain, frequent urination and nocturia; bilateral ureteral compression Suddenly there is no urine; because there is often hydronephrosis or kidney infection, so the tenderness of the waist is very common, high blood pressure is common (one of the causes of headache), mostly due to renal obstruction, because with the rupture of the ureter, After lysis or removal of a non-functional kidney, blood pressure can return to normal, and gastrointestinal symptoms can be related to uremia or direct damage to the gastrointestinal tract (such as shift stenosis).

It has been reported that the biliary tract and pancreatic duct stenosis, if involving the portal vein or splenic vein, can cause portal hypertension, esophageal varices and ascites, and the peritoneal or mesenteric lymphatic drainage is blocked by fibrosis, which can also cause protein loss. Intestinal disease or malabsorption, posterior peritoneal lymph, vein or arteriole compression or obstruction, one or both legs can be swollen, penile swelling or scrotal edema, even abdominal wall filling or varicose veins, lower extremity thrombosis, lower extremity Weak pulse, intermittent claudication, may be accompanied by fibrosis in other parts (such as the mediastinal bile duct), and even sclerosing cholangitis, Peyronie disease (Peloni disease, penile corpus cavernosum, resulting in fibrous painful penile erection, ie Fibrous cavernitis) and the like.

At the time of physical examination, there is often tenderness in the lower abdomen and lower back. The kidney area may have slap pain or touch the enlarged kidney. The posterior retroperitoneal fibrous mass is generally difficult to reach and may be accompanied by high blood pressure.

Examine

Examination of idiopathic retroperitoneal fibrosis

Laboratory inspection

1. Blood test: The erythrocyte sedimentation rate is accelerated, the hemoglobin is decreased, the total number of white blood cells is increased, and the percentage of eosinophils is increased.

2. Urine routine examination: generally no abnormalities, when there is a urinary tract infection, there may be white blood cells in the urine.

3. Renal function test: serum creatinine, urea nitrogen increased.

4. Plasma protein: The ratio of albumin to globulin (A/G) can be inverted, and the values of and globulin in globulin increase.

Film degree exam

1. X-ray inspection:

(1) Excretory urography:

1 bilateral renal pelvis, upper ureter dilatation, ureteral distortion.

2 The ureteral lumen is thin, even stiff, narrow, and the stenosis is generally located at the level of the 3rd and 4th lumbar vertebrae, 3 to 6 cm long, and the lumen is smooth.

3 The ureteral ureter was displaced to the midline at the same time.

4 When the ureter is completely obstructed, the affected kidney may not be developed.

(2) retrograde urography: When the IVU venous urinary tract angiography, the ureter is unclear, retrograde urography can be seen in the upper ureteral dilatation, the lumen is thinner, and the ureter is displaced to the median.

2. Cystoscopy: the bladder is generally normal, retrograde intubation is often difficult, when the ureteral catheter crosses the obstruction site, you can see the rapid drop of urine, which is the characteristics of this disease, once the ureteral catheter is pulled to the stenosis, The flow of urine is stopped.

3. B-ultrasound: can understand the hydronephrosis of the kidney and ureter, can show retroperitoneal fiber plaque, manifested as hypoechoic irregular solid mass around the abdominal aorta.

4. CT examination: it is the main means of diagnosis and follow-up of retroperitoneal fibrosis. It shows soft tissue shadows with different thickness around the aorta. It surrounds the aorta and inferior vena cava. The ureter is surrounded by a mass and has different degrees of kidney. In stagnant water, CT can show the active or degenerative phase of the lesion, but it is difficult to identify benign and malignant.

5. MRI: The anatomical position and shape of the fibrous plaque can also be well displayed. MRI can be multi-axially imaged, showing that the longitudinal extent of the plaque is superior to the CT examination, which shows the degree of stenosis of the abdominal large blood vessels and the collateral circulation. Clearer than CT.

6. Puncture biopsy: Acupuncture or biopsy of the retroperitoneal mass in the B-ultrasound or CT-guided follow-up helps to determine the nature of the lesion.

Diagnosis

Diagnosis and diagnosis of idiopathic retroperitoneal fibrosis

The diagnosis of this disease focuses on strengthening the understanding of this disease and raising vigilance. Anyone who takes painkillers and ergometrine regularly has unexplained back pain, abdominal pain, dull pain in the lower back or lower abdomen, and portal hypertension. Patients with protein-losing enteropathy should consider the possibility of this disease. B-mode ultrasound, CT and X-ray examinations can help diagnose. As long as the possibility of this disease is noted, diagnosis can be made according to medical history and radiology. .

Differential diagnosis

RPF should be differentiated from retroperitoneal lymphoma, proliferative lymphadenitis, metastatic tumor, primary tumor, peri-aortic hematoma and amyloidosis. In addition to clinical manifestations, imaging is mainly performed.

The characteristics of RPF are large mass, uniform density, and tight connection with the aorta; there is no obvious pressure displacement of the aorta itself and its surrounding organs; the distance between the aorta and the vertebral body does not change; the ureteral stricture is pulled to the center.

1. Ureteral calculi: The patient has lumbar pain and can radiate to the lower abdomen, vulva, and inner thighs. However, the pain caused by ureteral stones is mostly sudden, and the degree is more serious. It is unbearable. The urine routine examination before and after the attack may have red blood cells. Stone shadows can be found in the IVU.

2. Ureteritis: also shows low back pain, physical examination of the kidney area has sputum pain, but often urinary frequency, urgency, dysuria and other urinary tract irritation symptoms, IVU can be seen ureteral dilatation or stenosis, but no bilateral ureter simultaneously to the central Position, B-ultrasound and CT examination of ureter and no space-occupying lesions around the blood vessels

3. Inferior vena cava ureter: can be expressed as right side of the low back pain, B-ultrasound and IVU can be found in the right renal hydronephrosis, the right ureteral upper segment is dilated and displaced to the midline, so that the entire ureter is "S" shape, which is helpful for diagnosis.

4. Ureteral tumor: mainly manifested as dull pain in the waist. When the patient discharges a cord-like blood clot, it may be accompanied by renal colic. However, in addition to pain, the patient also has different degrees of hematuria, and IVU can see hydronephrosis. Ureteral filling defects and cup-like changes or renal non-development, cystoscopy may sometimes show tumors from the ureteral orifice or ureteral orifice spurting, CT examination showed no space-occupying lesions around the ureter.

5. Retroperitoneal tumor: can also be expressed as low back pain, B-ultrasound can be found hydronephrosis, IVU found ureter has a narrow segment, generally displaced to the outside, hydronephrosis and ureteral stricture is usually unilateral, also Can be bilateral, such as retroperitoneal metastases, there is a history of primary cancer, B-ultrasound and CT examination can find substantial space-occupying lesions after the retroperitoneum,

(1) Lymphoma: The retroperitoneal lymphoma has a wide range of facets, and it shows a large nodular mass in the plain scan. The density is uneven, which may be accompanied by mesenteric lymphadenopathy. There is no obvious change after augmentation. Aorta and vertebral body The spacing increases.

(2) Metastatic tumor: The metastatic tumor lacks fibrous tissue, and the performance is not continuous aortic lymphadenopathy. Mesenteric lymph node enlargement is strongly indicated as malignant lesion. After enhancement, the tumor is unevenly enhanced and nodular, and finally diagnosed. It also depends on tissue cytology.

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