Urinary Tract Infections

兒童尿路感染

Various bacterial infections in infants and children

Bacterial meningitis in infants older than 3 months

Acute articular rhumatism

Occult bacteremia and apparent source fever in infants and young children

Urinary tract infections in children

1 Urinary tract infection is defined as the presence of ≥ 5 × 104 colonies / mL in a urine sample collected by sampling or, in the older child, by repeated sampling with ≥105 colonies / mL. In young children, urinary tract infections are frequently associated with anatomical abnormalities. A urinary infection can cause fever, growth retardation, hypochondrial pain and signs of sepsis, especially in young children. The treatment is based on antibiotics. An imaging follow-up of the urinary tract is performed.

Urinary tract infection can involve the kidneys and / or the bladder. Sexually transmitted infections of the urethra (eg, gonococcal or chlamydial urethritis), although involving the urinary tract, are not usually called urinary tract infections.

Mechanisms to maintain normal urinary tract sterility include urinary acidity, free flow of urine, normality of emptying mechanisms, ureteral and urethral valve integrity, immunological defenses, and mucosal barriers. An abnormality of one of these mechanisms predisposes to urinary tract infections.

Etiology

At age 6, 3 to 7% of girls and 1 to 2% of boys had a urinary tract infection. The peak age of urinary tract infections is bimodal, with a peak in early childhood and another between the ages of 2 to 4 years (at the time of toilet training for many children). The girl-to-boy ratio ranges from 1: 1 to 1: 4 in the first 2 months of life (estimates vary, probably due to different proportions of uncircumcised male subjects in the study groups and the exclusion of infants with urologic abnormalities who are currently more frequently diagnosed in utero with prenatal ultrasound). The girl-to-boy ratio increases rapidly with age, approximately 2: 1 between 2 months and 1 year, 4: 1 in year 2, and> 5: 1 after 4 years. In girls, infections are usually ascending and less likely to cause bacteremia. The higher incidence of infections in girls beyond early childhood is attributed to the lower size of the female urethra and circumcision in boys.

The contributing factors in young children include

Malformations and obstructions of the urinary tract

Prematurity

Urinary catheters at home

In boys, no circumcision

Other contributing factors in young children are constipation and Hirschsprung's disease.

Predisposing factors in the older child include

Diabetes

Trauma

In women, sex

Urinary tract abnormalities in children

Urinary tract infections in children are markers of a possible urinary tract abnormality (eg, obstruction, neurogenic bladder, ureteral duplication); these abnormalities are particularly likely to lead to recurrent infections if vesico-ureteric reflux is present. About 20 to 30% of infants and young children aged 12 to 36 months who have a urinary tract infection have vesicoureteral reflux. The younger the child is during the first urinary tract infection, the greater the likelihood of vesicoureteral reflux. Vesico-ureteral reflux is classified by grade (classification by grade of vesicoureteral reflux *).