Urinary tract infection (UTI) is the most common serious bacterial infection among infants. Suprapubic aspiration and bladder catheterization are considered as the gold standard by the American Academy of Pediatrics for the diagnosis, yet it is painful and invasive. In contrast, the bladder stimulation technique has been shown to be a quick and non-invasive approach to collect urine in young infants. Actually, the investigators don't have data on bacterial contamination rates for clean-catch midstream urine collections using this technique

Urinary tract infection (UTI) is common in infants and needs to be diagnosed quickly. The risk for urinary tract infection before the age of 2 years is about 1-4% in boys and 3-8% in girls. A delay in diagnosis exposes to severe complications. In infants, the symptoms are not specific. A good urinalysis quality is therefore necessary for the diagnosis of UTI. Different techniques exist to collect urine samples in these children who do not control their urination yet: supra pubic aspiration, catheterization, urine collection bag and clean catch urine. The American Academy of Pediatrics (AAP) recommends supra pubic aspiration (1-9 % bacterial contamination) and urinary catheterization (8-14 % contamination) for collecting urine but these techniques are invasive and painful. The sterile bag is a non-invasive method of urine collection, with a high bacterial contamination rates (26-62%) leading to unnecessary antibiotic treatment. Finally, clean catch urine is an accepted urine sample to diagnose UTI according to the recommendations (13-27 % of bacterial contamination) but this method is only possible for potty-trained children. Recent studies (Herreros et al, Altuntas et al, Tran et al.) have shown that bladder stimulation, which consists of pubic tapping and lumbar massage, would be a new, effective, non-invasive and safe method of collecting urine in infants.

Bladder stimulation may be performed by a nurse or a physician. The steps of the bladder stimulation technique are as follows: (a) cleaning the genital area with warm water and soap b) bladder stimulation technique, requires the presence of 3 people: infants will be held under their armpits by a parent over the bed, with legs dangling in males and hips flexed in females. The nurse or technician will then alternate between bladder stimulation maneuvers: gentle tapping in the suprapubic area at a frequency of 100 taps per minute for 30 seconds followed by lumbar paravertebral massage maneuvers for 30 seconds. These two stimulation maneuvers will be repeated until micturition begins, or for a maximum of of 3 minutes.

However, the investigators do not have data on the bacterial contamination rate for urine sample using this new technique. the investigators hypothesize that the bladder stimulation is a technique for obtaining urine with a contamination rate equivalent to those obtained by bladder catheterization, in the diagnosis of febrile urinary tract infection in infants under 6 months of age.

Inclusion Criteria:

• Infants under the age of 6 months

• For whom an urine sample is required for the diagnosis of a urinary tract infection as follows:

  • fever > 39 °C without symptoms
  • fever > 38°C and uropathy or urinary tract infection
  • fever > 38°C and < 3 months
  • fever > 38 °C and > 48h
  • fever > 38 °C with sepsis signs

• Obtaining the authorization of the holders of parental authority

• Affiliation to French social security

Exclusion Criteria:

• Do exhibiting signs of vital distress (respiratory or circulatory or neurological)
• contraindication to bladder catheterization
• antibiotic therapy in the last 48 hours
• antibiotic prophylaxis in the last 48 hours