Treatment

• infants and children with a high risk of serious illness should be referred urgently to the care of a paediatric specialist
  
  
• infants younger than 3 months with a possible UTI should be referred immediately to the care of a paediatric specialist
  • NICE state that there are concerns about sepsis in infants under 3 months with suspected UTI, and usual practice is referral rather than the GP managing symptoms. So the committee recommended that all children under 3 months should be referred to specialist paediatric care and have a urine sample sent for urgent microscopy and culture (1,2)
  • treatment should be with parenteral antibiotics
    
• for infants and children 3 months or older with acute pyelonephritis/upper urinary tract infection (1):
  • consider referral to a paediatric specialist
  • treat with oral antibiotics for 7-10 days
  • use of an oral antibiotic with low resistance patterns is recommended, for example cephalosporin or co-amoxiclav
  • if oral antibiotics cannot be used, treat with an intravenous (IV) antibiotic agent such as cefotaxime or ceftriaxone for 2-4 days followed by oral antibiotics for a total duration of 10 days
    
    
• for infants and children 3 months or older with cystitis/lower urinary tract infection (1):
  • send urine for culture and susceptibility or dipstick in line with the NICE guideline on urinary tract infection for under 16s
  • treat with oral antibiotics for 3 days
    
    
• for lower urinary tract infection, treatment of choice for most children is a course of oral antibiotics
  • if the child is very sick or in infants parenteral therapy may be indicated e.g. cefotaxime

Child or young person under 16 years

• assess and manage fever in under 5s in line with the NICE guideline on fever in under 5s
  
  
• with all antibiotic prescriptions, advise:
  • possible adverse effects of antibiotics include diarrhoea and nausea
  • seeking medical help if symptoms worsen at any time, do not improve within 48 hours of taking the antibiotic, or the person becomes very unwell
    
    
• reassess at any time if symptoms worsen rapidly or significantly or do not improve in 48 hours of taking antibiotics, sending a urine sample for culture and susceptibility if not already done. Take account of:
  • other possible diagnoses
  • any symptoms or signs suggesting a more serious illness or condition
  • previous antibiotic use, which may have led to resistance
    
    
• refer to hospital if a person aged 16 or over has any symptoms or signs suggesting a more serious illness or condition (for example, sepsis)
  
  

Choice of antibiotic 1,2

First Choice:

• children aged 3 months and over - First choice 3, 4
  • trimethoprim - if low risk of resistance 5
    • 3 to 5 months, 4 mg/kg (maximum 200 mg per dose) or 25 mg twice a day for 3 days;
    • 6 months to 5 years, 4 mg/kg (maximum 200 mg per dose) or 50 mg twice a day for 3 days;
    • 6 to 11 years, 4 mg/kg (maximum 200 mg per dose) or 100 mg twice a day for 3 days;
    • 12 to 15 years, 200 mg twice a day for 3 days
  • OR
  • nitrofurantoin - if eGFR >=45 ml/minute6
    • 3 months to 11 years, 750 micrograms/kg four times a day for 3 days
    • 12 to 15 years, 50 mg four times a day or 100 mg modified-release twice a day for 3 days

Second Choice:

• children aged 3 months and over - Second choice (worsening lower UTI symptoms on first choice taken for at least 48 hours or when first choice not suitable) 3,4,7
  • nitrofurantoin - if eGFR >=45 ml/minute 6
    • 3 months to 11 years, 750 micrograms/kg four times a day for 3 days
    • 12 to 15 years, 50 mg four times a day or 100 mg modified-release twice a day for 3 days
  • OR
  • amoxicillin (only if culture results available and susceptible)
    • 1 to 11 months, 125 mg three times a day for 3 days;
    • 1 to 4 years, 250 mg three times a day for 3 days;
    • 5 to 15 years, 500 mg three times a day for 3 days
  • OR
  • cefalexin
    • 3 to 11 months, 12.5 mg/kg or 125 mg twice a day for 3 days;
    • 1 to 4 years, 12.5 mg/kg twice a day or 125 mg three times a day for 3 days;
    • 5 to 11 years, 12.5 mg/kg twice a day or 250 mg three times a day for 3 days;
    • 12 to 15 years, 500 mg twice a day for 3 days
      
      
• 1 check BNF for children (BNFC) for use and dosing in specific populations.
• 2 age bands apply to children of average size; in practice the prescriber will use these with other factors. Doses given are by mouth using immediate release medicines, unless otherwise stated.
• 3 check previous urine culture and susceptibility results and antibiotic prescribing. If receiving prophylactic antibiotics, treatment should be with a different antibiotic.
• 4 if 2 or more antibiotics are appropriate, choose the antibiotic with the lowest acquisition cost. Some children may also be able to take a tablet or part-tablet, rather than a liquid formulation if the dose is appropriate.
• 5 a lower risk of resistance may be more likely if not used in the past 3 months, previous urine culture suggests susceptibility (but this was not used), and in younger people in areas where data suggest resistance is low. Risk of resistance may be higher with recent use and in older people in care homes.
• 6 may be used with caution if eGFR 30-44 ml/minute to treat uncomplicated lower UTI caused by suspected or proven multidrug resistant bacteria and only if potential benefit outweighs risk (BNFC, August 2018)
• 7 if there are symptoms of pyelonephritis or the person has a complicated UTI, see the recommendations on choice of antibiotic in the NICE antimicrobial prescribing guideline on acute pyelonephritis
  
  

Some suggest that all children (boys and girls) should undergo appropriate investigations after the first proven urinary tract infection (3). NICE however suggest further investigation is based on the age of the child and the features of the UTI (1).

asymptomatic bacteriuria in infants and children should not be treated with antibiotics

Antibiotic prophylaxis (1):

• antibiotic prophylaxis should not be routinely recommended in infants and children following first-time UTI
• antibiotic prophylaxis may be considered in infants and children with recurrent UTI
• asymptomatic bacteriuria in infants and children should not be treated with prophylactic antibiotics

Notes:

• prevalence of bacterial resistance to amoxicillin is too high to recommend it as a first line treatment before sensitivity results are available

Reference:

1. NICE (September 2017).Urinary tract infection in children: diagnosis, treatment and long-term management .
2. NICE (October 2018). Urinary tract infection (lower): antimicrobial prescribing
3. Watson AR (2004). Pediatric Urinary Tract Infection. EAU Update series.