Urinary tract infection (UTI)

N30.9/N39.0/O23.4

DESCRIPTION

Urinary tract infections may involve the upper or lower urinary tract. Infections may be complicated or uncomplicated. Uncomplicated UTI is a lower UTI where there are no functional or anatomical anomalies in the urinary tract, no renal impairment, or no concomitant disease that would promote the UTI.

Differentiation of upper from lower urinary tract infection in young children is not possible on clinical grounds.

Upper UTI is a more serious condition and requires longer and sometimes intravenous treatment.

Features of upper UTI (pyelonephritis) that may be detected in adults and adolescents include:

  • flank pain/tenderness
  • temperature 38 degrees celcius or higher
  • other features of sepsis, i.e.:
    • tachypnoea,
    • tachycardia,
    • confusion, and
    • hypotension.
  • vomiting

In complicated, recurrent or upper UTIs, urine should be sent for microscopy, culture and sensitivity.

Features of urinary tract Infections in children

Signs and symptoms are related to the age of the child and are often non-specific. Uncomplicated urinary tract infections may cause very few signs and symptoms. Complicated infections may present with a wide range of signs and symptoms.

Neonates may present with:

  • fever
  • hypothermia
  • poor feeding
  • sepsis
  • vomiting
  • prolonged jaundice
  • failure to thrive
  • renal failure

Infants and children may present with:

  • failure to thrive
  • frequency
  • persisting fever
  • dysuria
  • abdominal pain
  • enuresis or urgency
  • diarrhoea

In any child with fever of unknown origin, the urine must be examined, to assess whether a urinary tract infection is present.

Perform a dipstix test on a fresh bag urine specimen.

DIPSTIX RESULT ACTION
No leukocytes/ nitrites UTI unlikely
Leukocytes only Repeat dipstix on a second specimen. If leucocytes on second specimen, suspect UTI and treat empirically. Collect urine aseptically if possible for urine MC&S.
Leukocytes or nitrites with symptoms of UTI Treat empirically for UTI.
Collect urine aseptically if possible for urine MC&S.
Leukocytes and nitrites Collect urine aseptically if possible for urine MC&S. Treat empirically for UTI.

GENERAL MEASURES

  • Women with recurrent UTIs should be advised to:
    • void bladder after intercourse and before retiring at night
    • not postpone voiding when urge to micturate occurs
    • change from use of diaphragm to an alternative type of contraception

MEDICINE TREATMENT

Empirical treatment is indicated only if:

  • positive leukocytes and nitrites on freshly passed urine, or
  • leucocytes or nitrites with symptoms of UTI, or
  • systemic signs and symptoms.

Alkalinising agents are not advised.

Uncomplicated cystitis

Adults

  • Gentamicin, IM, 160 mg, as a single dose.
    • Note: Gentamicin should not be used in patients with known chronic kidney disease or pregnancy.

LoEII [3]

  • If gentamicin is unavailable/ contra-indicated:
    • Fosfomycin, oral, 3 g as a single dose.

LoEI [4]

  • If fosfomycin is unavailable:
  • Nitrofurantoin, oral, 100 mg 6 hourly for 5 days.

LoEIII [5]

Complicated cystitis

Adults

  • Ciprofloxacin, oral, 500 mg 12 hourly for 7 days.

Children ≤ 35 kg who do not meet criteria for urgent referral :

  • Amoxicillin/clavulanic acid oral, 15–25 mg/kg/dose of amoxicillin component, 8 hourly for 7 days.
Weight
kg 		Dose
mg
(amoxicillin component) 		Use one of the following Age
months/years
Susp
125/31.5
mg/5 mL 		Susp
250/62.5
mg/5 mL 		Tablet
500/125 mg/tab
>5–7 kg 100 mg 4 mL 2mL – >3–6 months
>7–9 kg 150 mg 6 mL 3 mL – >6–12 months
>9–11 kg 200 mg 8 mL 4 mL – >12–18 months
>11–14 kg 250 mg 10 mL 5 mL – >18 months–3 years
>14–17.5 kg 300 mg 12 mL 6 mL – >3–5 years
>17.5–25 375 mg 15 mL 7.5 mL – >5–7 years
>25–35 kg 500 mg 20 mL 10 mL 1 tablet >7–11 years

LoEIII [6]

Acute pyelonephritis

N10
Outpatient therapy is only indicated for women of reproductive age, who do not have any of the manifestations requiring referral (see referral criteria below). All other patients should be referred.

  • Ciprofloxacin, oral, 500 mg 12 hourly for 7–10 days.
    • It is essential to give at least a 7 day course of therapy.

REFERRAL

Urgent

  • Acute pyelonephritis with:
    • vomiting
    • sepsis
    • diabetes mellitus
  • Acute pyelonephritis in:
    • pregnant women
    • women beyond reproductive age
    • men
  • Children > 3 months of age who appear ill.
  • Children < 3 months of age with any UTI.

Ill patients awaiting transfer

  • Ensure adequate hydration with intravenous fluids.
    • Ceftriaxone, IM, 80 mg/kg/dose immediately as a single dose. See paediatric dosing tool.
      • Do not inject more than 1 g at one injection site.

CAUTION: USE OF CEFTRIAXONE IN IN NEONATES AND CHILDREN

  • If SUSPECTING SERIOUS BACTERIAL INFECTION in neonate, give ceftriaxone, even if jaundiced.
  • Avoid giving calcium-containing IV fluids (e.g. Ringer Lactate) together with ceftriaxone:
    • If ≤ 28 days old, avoid calcium-containing IV fluids for 48 hours after ceftriaxone administered.
    • If >28 days old, ceftriaxone and calcium-containing IV fluids may be given sequentially provided the giving set is flushed thoroughly with sodium chloride 0.9% before and after.
    • Preferably administer IV fluids without calcium contents
  • Always include the dose and route of administration of ceftriaxone in the referral letter.

Non-urgent

  • All proven UTIs (positive culture) in children after completion of treatment.
  • No response to treatment.
  • UTI > 3 times within a one-year period in women, and > 1 time in men.
  • Recurrent UTI in children for assessment and consideration of prophylaxis.