Solitary renal ectopia

　　First, etiology

　　Under normal circumstances, by the end of the 8th week of fetal development, both kidneys have reached the level of the second lumbar vertebra. The formation of ectopic kidney occurs during the renal ascent process in the 4th to 8th week of fetal development. Due to factors such as the obstruction of ureteral bud growth, abnormal blood supply, or excessive growth of Wolffian duct, the renal ascent may stop, accelerate, or rise incorrectly to the opposite side, resulting in renal ectopia or malrotation.

　　Second, pathogenesis

　　Ectopic kidney is different from nephropexy, the latter initially being in the normal position with normal blood vessels and ureters. Ectopic kidneys are usually smaller, about 60% located in the pelvis, with shorter ureters, and the supplying blood vessels come from the lower segment of the aorta and the main branches of the pelvic blood vessels and are often branched. If the kidney continues to rise in the 8th week of embryogenesis, part of the kidney or the entire kidney may pass through the diaphragm into the posterior mediastinum, forming intrathoracic kidney, accounting for about 5%, with the ureter being elongated, but with normal blood supply and no malrotation of the kidney. Cross-ectopic kidneys can be divided into fused and non-fused types, with the ureters often entering the bladder through the normal path and opening normally in the trigone.

　　It often accompanies malrotation of the kidney (the renal pelvis facing forward) and other malformations such as hypospadias, cryptorchidism, underdevelopment of the vagina, cardiovascular malformations, gastrointestinal and skeletal malformations, etc.

　　1. Urethral ectropia refers to the opening of the urethra on the ventral side of the urethra, known as hypospadias. The opening of hypospadias can occur at any location between the perineum and the glans penis. The distal end of the external urethral opening, the underdevelopment of the urethra and surrounding tissues, forms fibrous cords that pull the penis towards the ventral side. Not all congenital penile curvature downwards have hypospadias, but all degrees of hypospadias have some degree of penile curvature downwards.

　　2. Cryptorchidism refers to the failure of one or both testicles to descend from the posterior parietal region of the waist to the ipsilateral scrotum according to the normal development process. It is also known as incomplete descent of the testicles and is one of the most common congenital diseases of the male reproductive system in children.

　　3. Orthopedic correction refers to the abnormality or defect in the volume, shape, location, or structure of organs or tissues, resulting in deformity. Early symptoms of deformity are not easy to be discovered and are often delayed in treatment. This phenomenon is relatively common in infants.

　　Pelvic kidneys can be palpated as masses in the lower abdomen. Due to the low position of the kidney, it may be associated with vesicoureteral reflux or obstruction at the renal pelvis ureteral junction, easily leading to hydronephrosis, infection, and stone formation, manifested as swelling and pain in the renal area, hematuria, and pyuria. Or, due to compression of blood vessels, nerves, and nearby organs, lower abdominal pain, gastrointestinal symptoms, and bladder irritation symptoms may occur.

　　Strengthen prenatal education, ensure reasonable nutrition before and during pregnancy, maintain health, and avoid the use of harmful drugs to prevent teratogenic effects. In addition, early detection, early diagnosis, and early treatment are the key to the prevention and treatment of the disease. Once the disease occurs, active treatment should be carried out to prevent the occurrence of complications.

　　With the application of radiographic imaging, ultrasound, radionuclide scanning, and other urinary tract imaging technologies, the diagnosis of asymptomatic ectopic kidneys has been gradually improved. Secretive urography or kidney ultrasound examination can easily determine the diagnosis. In addition, radionuclide scanning, retrograde urography, and CT can often provide useful information for diagnosis. Simple cystoscopy is not sufficient to diagnose renal ectopia unless the ureteral orifice also occurs abnormally, suggesting an upper urinary tract lesion. Angiography examination can be helpful in understanding the renal blood flow condition and determining the surgical plan, especially for unilateral ectopic kidneys.

　　1. What foods are good for simple renal ectopia:Eat light and easy-to-digest foods, fresh vegetables, and moderate amounts of fruit. Drink water appropriately. Pay attention to the balance of dietary nutrition.

　　2. What foods should be avoided for simple renal ectopia:Avoid overeating and eating unclean food. Avoid seafood, beef, mutton, spicy and刺激性 food, alcohol, and all kinds of promoting agents such as five-spice powder, coffee, coriander, etc. Avoid eating all kinds of tonics, tonics, and easy-to-heat food such as chili, intelligence, chocolate, etc.

　　(The above information is for reference only; for details, please consult a doctor.)

　　I. Treatment

　　Unsymptomatic individuals do not need treatment; symptomatic treatment should be given to those with complications. In cases with severe complications such as severe hydronephrosis or abscess, nephrectomy of the diseased kidney can be performed if the contralateral kidney is normal.

　　II. Prognosis

　　Except for urinary tract stones or hydronephrosis, ectopic kidneys do not have a higher susceptibility than normal kidneys. This is mainly due to the anterior position of the renal pelvis and poor rotation of the kidneys, or due to ectopic blood vessels compressing the renal pelvis or upper ureter, which affects the normal drainage of urine. In addition, due to the lack of rib protection, the lower kidneys are prone to trauma, and there are reports that variant blood supply can cause renovascular hypertension. Although there are reports of two cases of primary tumors in ectopic kidneys, there is no evidence to confirm that ectopic kidneys have a higher malignancy rate. There have been no reports of death directly caused by ectopic kidneys.