Infant babies cry, have fever, do not take milk well, and the child does not cough or wheeze, much less have diarrhea. Be sure to rule out a urinary tract infection. On average, one in forty male babies under the age of one will have a urinary tract infection (2.7%), curiously fewer female babies in this age group (0.4%). It is also possible that there is more vesicoureteral reflux in males. However, by school age children, girls have three times more urinary tract infections than boys (0.03-1.2% for boys and 1-3% for girls). It is possible that this is related to the short urethra. Most of the bacteria from feces enter the urethra and bladder from the perineum. In children with vesicoureteral reflux, bacteria are more likely to enter the kidney and cause nephritis. Some Escherichia coli (E. coli), which attach to the urethral bladder epithelium by specific bacterial hairs (pili) and umbrella hairs (fimbriae), are the most common bacteria causing urinary tract infections. Some bacteria come from the space between the foreskin and the glans. Circumcised boys have an exposed, drier glans and are 10-12 times less likely to have a urinary tract infection. After puberty, girls who start having sex or become pregnant increase their chances of getting a urinary tract infection. Why are you so nervous about urinary tract infections? Because growing kidneys are more fragile than adults, and 17% of urinary tract infections cause permanent damage to the kidney, leaving a scar. And 10-20% of these children with scarred kidneys will have high blood pressure. This shows the seriousness of urinary tract infections. Rule out congenital urinary tract abnormalities. Unlike adults, it is important to rule out congenital urinary tract abnormalities in infants under six months of age because the first clinical sign of many abnormalities such as hydronephrosis and vesicoureteral reflux is a urinary tract infection. If babies are infected before they are born, the probability of congenital disease is much higher than in adults. UK NICE guidelines recommend ultrasound for all babies with urinary tract infections under six weeks. For recurrent infections (second or more inflammations) or infections caused by uncommon bacteria, children should have a voiding cystourethrography to rule out vesicoureteral reflux, posterior urethral valves or ureteral dilatation, and abnormalities of the bladder gap chamber. An isotope renogram (DMSA) is also recommended to determine renal function and to explore the extent of renal scarring. Parents need not worry about isotopes, which are only one-fifth the radiation of a single X-ray. After treating these infants under six months of age, UK GPs will see a pediatric urologist to rule out congenital malformations. Urinary anomalies prevent the complete and fluid elimination of urine, giving bacteria the opportunity to multiply. 1. Incomplete urination (1) Vesicoureteral reflux, where some urine always refluxes into the ureter or renal pelvis and urine cannot be completely excreted. (2) Repeated kidney, the upper kidney usually functions very poorly, plus the hydronephrosis, that is, the urine flows very slowly, just like a stinky ditch, and it is easy to inflame. (3) Neurogenic bladder, where the urethral sphincter cannot relax and the urine in the bladder cannot be removed, causing chronic urinary Chuchu flow and reflux. (4) paraureteral bladder diverticulum (Hutch diverticulum), urination is not clean. 2, urinary system obstruction (1) renal pelvic ureteral interface stenosis, causing hydronephrosis; (2) vesicoureteral interface stenosis, causing giant ureter; (3) posterior urethral valves, causing poor urination, neurogenic bladder, giant ureter, hydronephrosis, etc.; (4) ureteral bulge, its cysts can cause ureteral obstruction, large may be willing to block the bladder neck, poor urination. These congenital urinary anomalies, although not present in every child, should be thoroughly examined and should not wait until there is recurrent inflammation and permanent damage to the kidney or bladder before seeing a pediatric urologist.