On July 9, a “kindergarten teacher punished the boy to drink water caused by hydronephrosis” news attracted the attention of many netizens. According to media reports, a 5-year-old boy in Wuhan was punished by his teacher to drink more than 20 cups of water for frolicking during dinner, parents said that the child said he could not drink the 10th cup of water, the teacher still wanted him to drink, resulting in hydronephrosis, which has not been healed by surgery. The garden said that the child only drank 3 cups of milk, 10 times water (no more than 30 ml each time), and excessive water will not lead to hydronephrosis, the teacher involved has left the post. Children drink too much water will also cause hydronephrosis? Wang Dejuan, deputy director of urology at the Third Hospital of Sun Yat-sen University, pointed out that most pediatric hydronephrosis is due to congenital ureteral abnormalities, such as common ureteral stenosis leading to urine accumulation in the renal pelvis, in general, drinking water does not directly lead to the occurrence of pediatric hydronephrosis, but may induce or aggravate the condition. 80% of pediatric hydronephrosis “killers” – obstruction at the ureteral junction of the renal pelvis The ureter in children is very thin, the upper end is connected to the renal pelvis, the lower end is connected to the bladder and urethra, any blockage of the ureter may lead to the accumulation of urine in the kidney pelvis, causing Any blockage of the ureter may cause the child’s urine to accumulate in the renal pelvis, causing hydronephrosis. In contrast, pelvic ureteral junction obstruction (UPJO) is a blockage at the point where the renal pelvis and ureter join, preventing urine from the pelvis from draining smoothly into the ureter, preventing the pelvis from emptying urine and causing the kidney’s collecting system to expand. “Eighty percent of pediatric hydronephrosis is the result of UPJO,” notes Wang Dejuan, adding that many children have abnormal ureteral growth while in their mother’s womb, and if they are not treated promptly after birth, hydronephrosis is a matter of time. In addition, 7 percent of pediatric hydronephrosis is the result of vesicoureteral reflux. The normal ureter connected to the bladder has a valve-like function, which only allows urine to flow from the ureter into the bladder, but does not allow the backflow of urine from the bladder to the ureter. However, due to congenital underdevelopment of the valve, urinary obstruction and other reasons, the valve-like function “fails” and urine flows back into the ureter, reaching the kidney in severe cases. If congenital causes are ruled out, can a child develop hydrocele later in life? Wang Dejuan said that if a child has a sudden kidney stone and the stone is blocked in the ureter, it may also cause hydronephrosis, but the chance of hydronephrosis caused by drinking water alone is relatively small, and the amount of “3 glasses of milk and 10 times of water (no more than 30 ml each time)” is not enough to cause severe hydronephrosis. However, if the child has UPJO or other abnormalities, the condition may be triggered or aggravated by drinking large amounts of water. According to the admission record provided by the boy’s parents, an ultrasound examination at Wuhan Puai Hospital revealed severe hydronephrosis in the left kidney and significant dilatation of the upper left ureter (possible stenosis of the upper left ureter), but no special treatment was performed. The “possible upper left ureteral stenosis” suggested by the hospital is most likely due to the child’s congenital ureteral abnormality, which causes urine to easily accumulate in the kidney and cause severe hydronephrosis after reaching a certain amount. The vast majority of pediatric UPJO can be detected prenatally Congenital abnormalities of the ureter in children can be detected when the mother is in the womb. Wang Dejuan pointed out that most of the UPJO can be clearly diagnosed by prenatal ultrasound before the birth of the child, and mothers can detect the problem in time as long as they keep regular maternity checkups. If prenatal hydrocele is detected, it depends on the degree and extent of the hydrocele, or the weight of ureteral stasis, combined with malformations, etc. to determine whether intervention is needed. It is understood that an ultrasound examination that indicates “dilated renal pelvis (renal collecting system) R10 mm or the presence of dilated calyces” is called hydronephrosis. When the renal pelvis is dilated beyond 20 mm, clinical management is required. If the diagnosis of UPJO is confirmed, open or laparoscopic dissection of the pyeloplasty is required. Postoperative restenosis of the anastomosis may occur and requires close follow-up. Pediatric patients are highly resilient and require every effort to preserve the kidney, even in the presence of severe hydronephrosis, unless there is a thin, nonsecretory, recurrent infection in the affected kidney cortex. “Prenatal hydronephrosis can be treated after birth if it is not evaluated for severe bilateral hydronephrosis causing pulmonary insufficiency and fetal life threatening conditions.” So said Wang Dejuan. Wang Dejuan reminded that it is difficult for children to dictate urinary tract symptoms clearly, so parents should take their children to the pediatric urology or pediatric surgery department to find out if they notice sudden onset of high fever, hematuria, purulent urine, frequent urination, urgent urination, painful urination and abdominal pain.