Horseshoe kidney

　　What are the causes of the onset of horseshoe kidneys

　　The pathogenic factors of horseshoe kidneys are mainly congenital. During embryonic development from 4 to 6 weeks, the posterior renal tissues approach each other, and many influencing factors can lead to fusion at the lower pole at this time. Minor changes in the umbilical artery or iliac artery can cause the direction of the migrating kidneys to change, leading to fusion of the two kidneys. Regardless of the formation mechanism, renal fusion always occurs before rotation, so the kidneys and ureters often face forward.

　　What complications can horseshoe kidneys easily cause

　　What are the typical symptoms of horseshoe kidneys

　　In addition to the possible abdominal mass, horseshoe kidneys often have no specific symptoms, and clinical manifestations are non-specific. Patients may have no symptoms at all, and some may be misdiagnosed with abdominal tumors, appendicitis, pancreatitis, duodenal ulcers, or seek medical attention due to complications. For those with clinical manifestations, they can be divided into three types of symptoms: one is lumbar or umbilical pain, lower abdominal mass; another is gastrointestinal disorder symptoms, such as bloating, constipation, etc.; the third is urinary system combined symptoms, such as infection, hydronephrosis, calculus, etc., accompanied by symptoms such as frequent urination, purulent urine, hematuria, etc. Due to the high position of the ureteral orifice in the renal pelvis and the restriction of renal fusion, the ureter cannot rotate normally, and when it passes over the fusion part, it moves forward, leading to poor urine flow, which causes 80% of cases to have hydronephrosis, and it is also easy to cause infection and calculus.

　　Due to the fact that patients with horseshoe kidneys often have other congenital anomalies in other systems, some of these defects can easily lead to early death. The evidence of familial inheritance of horseshoe kidneys is insufficient, and they are often discovered due to the presence of other congenital anomalies even without symptoms, so regular prenatal examinations and active prevention are recommended. Prenatal ultrasound can detect abnormalities before birth, and its imaging features are very easy to diagnose, so it is important to adhere to early detection, early diagnosis, and early treatment.

　　Excretory urography shows that the renal pelvis and calyces on both sides are low, and the lower poles of the two kidneys are close to the spine, so the extension line of the lower pole of the kidney is opposite to the normal renal pelvis, crossing in the caudal direction. Due to poor rotation, the renal pelvis and calyces are heavily overlapped, and even the calyces point inward, the renal pelvis turns outward, and the upper ureter bends outward. Sometimes, compression by blood vessels, fibrous bands, or the isthmus can cause hydronephrosis. Careful observation may show abnormal shadows of the kidney and isthmus on the KUB flat film. Ultrasound examination can detect the malformed horseshoe kidney. Renal radionuclide scanning can understand whether there is renal parenchymal tissue at the isthmus. Abdominal aortic angiography is very helpful in determining the surgical method.

　　Dietary attention for horseshoe kidney:
　　1. Suitable foods for horseshoe kidney: Eat light and easily digestible foods, fresh vegetables, and moderate amounts of fruit, and drink adequate water.
　　2. Dietary taboos for horseshoe kidney: Avoid overeating and eating unclean food. Avoid seafood, beef, mutton, spicy and刺激性 food, alcohol, and all kinds of irritants such as five-spice powder, coffee, coriander, etc. Avoid all tonics, tonics, and easily spicy foods such as chili, lychee, chocolate, etc.

　　Patients with horseshoe kidney generally do not need treatment if they are asymptomatic and without complications. When clinical symptoms affect work and life, consider performing ureterolysis, segmental resection and separation, and the shaping and fixation of the two kidneys and renal pelvis and ureter. Those with complications need to be treated according to specific circumstances, such as performing pyeloplasty if there is obstruction at the renal pelvis and ureter junction. The operation usually involves a standard lumbar incision, and careful separation should be made during the operation to avoid injury to the abnormal distribution of renal blood vessels when displaying the kidney. Often, it can be found that the renal vein crosses the renal pelvis and ureter junction, which should be ligated and cut to relieve the obstruction here. The ureter usually opens at a high position in the renal pelvis and should be fully mobilized and exposed. A Y-V pyeloplasty should be performed below the renal pelvis and ureter junction to widen the junction and ensure unobstructed drainage. If there is vesicoureteral reflux, perform vesicoureteral reanastomosis. Currently, it is rarely performed to simply resect the isthmus, as this has little effect on improving flow, correcting the position of the kidney and ureter.