Dr Sonya Jey offers top tips on the diagnosis and management of urinary tract infection in different situations in primary care

Jey, Sonya

Dr Sonya Jey

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Read this article to learn more about:

  • categorising urinary tract infections
  • managing suspected pyelonephritis and when to refer
  • prescribing antibiotics and offering patients advice.

Urinary tract infections (UTIs) are commonplace in general practice and present frequently. They are especially common in females throughout the different stages of their lives. It is useful to pay special attention to patients who are at higher risk of complications. This article draws on recommendations from NICE and Public Health England, as well as from the European Association of Urology guidelines.

These top tips focus on patients aged 16 years or over; for advice on the diagnosis and management of UTIs in children and young people, see relevant recommendations in:

  • NICE Clinical Guideline 54, Urinary tract infection in under 16s: diagnosis and management
  • NICE Guideline 143, Fever in under 5s: assessment and initial management
  • NICE Guideline 111, Pyelonephritis (acute): antimicrobial prescribing
  • NICE pathway on urinary tract infections
  • NICE Guideline 109, Urinary tract infection (lower): antimicrobial prescribing.

1. Recognise the different categories of UTIs

Urinary tract infections can be classified as uncomplicated, complicated, recurrent, catheter-associated, or urosepsis:1

  • uncomplicated UTI: acute, sporadic, or recurrent lower (uncomplicated cystitis) and/or upper (uncomplicated pyelonephritis), in non-pregnant, premenopausal women who have no relevant anatomical or functional abnormalities of the urinary tract and no other co-morbidities
  • complicated UTI: occurs in patients with an increased chance of a complicated course
  • recurrent UTI: at least three per year or two in the last 6 months
  • catheter-associated UTI: UTI in a person whose urinary tract is currently catheterised or who has had a catheter in situ within the past 48 hours
  • urosepsis: life-threatening organ dysfunction caused by a dysregulated host response to infection originating from the urinary tract and/or male genital organs.

2. Be familiar with the pathogenesis of UTIs

Escherichia coli accounts for 70–95% of cases of UTI. Staphylococcus saprophyticus accounts for 5–10% of cases and other pathogens include other Enterobacteriaceae such as Proteus mirabilis and Klebsiella species.2

3. Know the risk factors for developing UTIs

Risk factors for developing an uncomplicated UTI include sexual intercourse, use of spermicide, a new sexual partner, a mother with a history of UTI, and a history of UTI during childhood.1

Factors associated with complicated UTIs include structural abnormalities or malformations of the urinary tract, obstructive pathology such as urinary tract calculi, prostatic hyperplasia and incomplete emptying of the bladder, pregnancy, an oestrogen-deficient state in women, dehydration, diabetes and other immunosuppressive conditions.1 Men, those with renal insufficiency, and the debilitated elderly are considered special groups.2

4. Remember the symptoms and signs of UTIs and pyelonephritis

Symptoms of a lower UTI in adults can include urinary frequency/urgency, dysuria, new-onset nocturia, turbid (cloudy) urine, haematuria, and suprapubic tenderness.3

Pyelonephritis can present with fever (>38°C), chills, flank pain, nausea, vomiting, or renal angle tenderness, with or without the typical symptoms that present with a lower urinary tract infection.1

As well as these specific urinary tract symptoms, elderly people can present with increased debility, worsening cognition, and recent-onset incontinence.3

5. Diagnose and treat appropriately; change treatment if indicated

Treat non-pregnant, pre-menopausal women clinically and offer these women an immediate prescription for antibiotic treatment if their clinical symptoms warrant this.1 Deferred antibiotic therapy can be considered in non-pregnant women with mild symptoms; advise these women to commence treatment if the symptoms get no better after 48 hours, or if they get worse.2

In men or pregnant women with lower UTI, offer an immediate appropriate empirical antibiotic (see tip 7); you should also obtain a midstream urine sample before antibiotics are taken, and send this for culture and susceptibility testing. Note that urine dipstick tests are less useful in those aged over 65 years, especially if these people are debilitated, as they are more likely to have an asymptomatic bacteriuria (see below).

A key message from NICE is to review/change treatment in accordance with lab report antibiotic sensitivities and reassess if symptoms are not improving after 48 hours of generic treatment.2

Asymptomatic bacteriuria

Asymptomatic bacteriuria (ABU) is a condition where there are significant levels of bacteria (greater than 105 colony forming units/ml) in the urine in the absence of symptoms of UTI. Treat pregnant women whose mid-stream sample suggests ABU to reduce the risk of pyelonephritis (upper urinary tract infection) and preterm delivery.2

Catheterised patients

Catheter-specimen urine dipstick-testing is not advised in asymptomatic patients. In a symptomatic patient who has a catheter, best practice is to take a sample of urine for culture at the point of changing catheter and treating clinically.3

6. Know how to manage suspected pyelonephritis

In adults aged 16 years and over with suspected pyelonephritis:4

  • admit people to hospital who have symptoms or signs suggesting a more serious illness or condition, such as sepsis
  • consider referring or seeking specialist advice for people with acute pyelonephritis if they:
    • are significantly dehydrated or unable to tolerate oral fluids and medicines or
    • are pregnant or
    • have a higher risk of developing complications (for example, people with known or suspected structural or functional abnormality of the genitourinary tract or underlying disease [such as diabetes or immunosuppression]).

Tables 1 and 2 show suggested regimens for oral antimicrobial therapy in uncomplicated acute pyelonephritis.4

Table 1: Antibiotics for non-pregnant women and men aged 16 years and over with acute pyelonephritis4
Antibiotic[A]Dosage and course length

First-choice oral antibiotics[B]

Cefalexin

500 mg twice or three times a day (up to 1 to 1.5 g three or four times a day for severe infections) for 7 to 10 days

Co-amoxiclav (only if culture results available and susceptible)

500/125 mg three times a day for 7 to 10 days

Trimethoprim (only if culture results available and susceptible)

200 mg twice a day for 14 days

Ciprofloxacin (consider safety issues[C])

500 mg twice a day for 7 days

Intravenous antibiotics

Refer to the full guideline for advice on first and second choices of intravenous antibiotics (if vomiting, unable to take oral antibiotics, or severely unwell).

[A] See British National Formulary (BNF) for appropriate use and dosing in specific populations, for example, hepatic impairment, renal impairment and breastfeeding, and administering intravenous antibiotics

[B] Check any previous urine culture and susceptibility results and antibiotic prescribing and choose antibiotics accordingly

[C] See MHRA advice for restrictions and precautions for using fluoroquinolone antibiotics due to very rare reports of disabling and potentially long-lasting or irreversible side effects affecting musculoskeletal and nervous systems. Warnings include: stopping treatment at first signs of a serious adverse reaction (such as tendonitis), prescribing with special caution in people over 60 years and avoiding coadministration with a corticosteroid (March 2019).

Adapted from: © NICE 2018 Pyelonephritis (acute): antimicrobial prescribing. Available from www.nice.org.uk/guidance/ng111 All rights reserved. Subject to Notice of rights
NICE guidance is prepared for the National Health Service in England. All NICE guidance is subject to regular review and may be updated or withdrawn. NICE accepts no responsibility for the use of its content in this product/publication. See www.nice.org.uk/re-using-our-content/uk-open-content-licence for further details.

Table 2: Antibiotics for pregnant women aged 12 years and over with acute pyelonephritis4
Antibiotic[A]Dosage and course length

First-choice oral antibiotic[B]

Cefalexin

500 mg twice or three times a day (up to 1 to 1.5 g three or four times a day for severe infections) for 7 to 10 days

Treatment escalation

Refer to the full guideline for advice on first-choice intravenous antibiotics (if vomiting, unable to take oral antibiotics, or severely unwell) and second-choice antibiotics or combining antibiotics if susceptibility or sepsis a concern.

[A] See British National Formulary (BNF) for appropriate use and dosing in specific populations, for example, hepatic impairment and renal impairment, and administering intravenous antibiotics

[B] Check any previous urine culture and susceptibility results and antibiotic prescribing and choose antibiotics accordingly

Adapted from: © NICE 2018 Pyelonephritis (acute): antimicrobial prescribing. Available from: www.nice.org.uk/guidance/ng111 All rights reserved. Subject to Notice of rights
NICE guidance is prepared for the National Health Service in England. All NICE guidance is subject to regular review and may be updated or withdrawn. NICE accepts no responsibility for the use of its content in this product/publication. See www.nice.org.uk/re-using-our-content/uk-open-content-licence for further details.

7. Know what advice to give for lower UTIs and which antibiotics to prescribe

Offer simple self-care advice on analgesia and hydration. Paracetamol should be used first line; however, if non-steroidal anti-inflammatory drugs (NSAIDs) are preferred, they may be used as long as there is no renal impairment or other contraindication.2 Antibiotic choices for non-pregnant women aged 16 years and over, pregnant women aged 12 years and over, and men aged 16 years and over, are summarised in Table 3, Table 4, and Table 5, respectively.2

Table 3: Antibiotics for non-pregnant women aged 16 years and over with lower UTI2
Antibiotic[A]Dosage and course length[B]

First choice[C]

Nitrofurantoin—if eGFR ≥45 ml/minute[D]

100 mg modified-release twice a day (or if unavailable 50 mg four times a day) for 3 days

Trimethoprim—if low risk of resistance[E]

200 mg twice a day for 3 days

Second-choice (no improvement in lower UTI symptoms on first-choice taken for at least 48 hours, or when first-choice not suitable)[C],[F]

Nitrofurantoin—if eGFR ≥45 ml/minute[D] and not used as first-choice

100 mg modified-release twice a day (or if unavailable 50 mg four times a day) for 3 days

Pivmecillinam (a penicillin)

400 mg initial dose, then 200 mg three times a day for a total of 3 days

Fosfomycin

3 g single dose sachet

[A] See British National Formulary (BNF) for appropriate use and dosing in specific populations, for example, hepatic impairment, renal impairment and breastfeeding.

[B] Doses given are by mouth using immediate-release medicines, unless otherwise stated.

[C] Check any previous urine culture and susceptibility results and antibiotic prescribing and choose antibiotics accordingly.

[D] 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 (BNF, August 2018).

[E] 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 local epidemiology data suggest resistance is low. A higher risk of resistance may be more likely with recent use and in older people in residential facilities.

[F] If there are symptoms of pyelonephritis or the person has a complicated UTI (associated with a structural or functional abnormality, or underlying disease, which increases the risk of a more serious outcome or treatment failure), see the recommendations on choice of antibiotic in the NICE guideline on pyelonephritis (acute): antimicrobial prescribing.

UTI=urinary tract infection; eGFR=estimated glomerular filtration rate

© NICE 2018. Urinary tract infection (lower): antimicrobial prescribing. Available from: www.nice.org.uk/guidance/ng109 All rights reserved. Subject to Notice of rights. NICE guidance is prepared for the National Health Service in England. All NICE guidance is subject to regular review and may be updated or withdrawn. NICE accepts no responsibility for the use of its content in this product/publication. See www.nice.org.uk/re-using-our-content/uk-open-content-licence for further details.

Table 4: Antibiotics for pregnant women aged 12 years and over with lower UTI or asymptomatic bacteriuria2
Antibiotic[A]Dosage and course length[B]

Treatment of lower UTI

First choice[C]

Nitrofurantoin (avoid at term)—if eGFR ≥45 ml/minute[D],[E]

100 mg modified-release twice a day (or if unavailable 50 mg four times a day) for 7 days

Second-choice (no improvement in lower UTI symptoms on first-choice taken for at least 48 hours or when first-choice not suitable)[C],[F]

Amoxicillin (only if culture results available and susceptible)

500 mg three times a day for 7 days

Cefalexin

500 mg twice a day for 7 days

Alternative second-choices

Consult local microbiologist, choose antibiotics based on culture and susceptibility results

Treatment of asymptomatic bacteriuria

Choose from nitrofurantoin,[D],[E] amoxicillin, or cefalexin based on recent culture and susceptibility results

[A] See British National Formulary (BNF) for appropriate use and dosing in specific populations, for example, hepatic impairment and renal impairment.

[B] Doses given are by mouth using immediate-release medicines, unless otherwise stated.

[C] Check any previous urine culture and susceptibility results and antibiotic prescribing and choose antibiotics accordingly.

[D] Avoid at term in pregnancy; may produce neonatal haemolysis (BNF, August 2018).

[E] 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 (BNF, August 2018).

[F] If there are symptoms of pyelonephritis or the person has a complicated UTI (associated with a structural or functional abnormality, or underlying disease, which increases the risk of a more serious outcome or treatment failure), see the recommendations on choice of antibiotic in the NICE guideline on pyelonephritis (acute): antimicrobial prescribing.

UTI=urinary tract infection; eGFR=estimated glomerular filtration rate

© NICE 2018. Urinary tract infection (lower): antimicrobial prescribing. Available from: www.nice.org.uk/guidance/ng109 All rights reserved. Subject to Notice of rights. NICE guidance is prepared for the National Health Service in England. All NICE guidance is subject to regular review and may be updated or withdrawn. NICE accepts no responsibility for the use of its content in this product/publication. See www.nice.org.uk/re-using-our-content/uk-open-content-licence for further details.

Table 5: Antibiotics for men aged 16 years and over with lower UTI2
Antibiotic[A]Dosage and course length[B]

First choice[C]

Trimethoprim

200 mg twice a day for 7 days

Nitrofurantoin—if eGFR ≥45 ml/minute[D],[E]

100 mg modified-release twice a day (or if unavailable 50 mg four times a day) for 7 days

Second-choice (no improvement in UTI symptoms on first-choice taken for at least 48 hours or when first-choice not suitable)[C]

Consider alternative diagnoses and follow recommendations in the NICE guidelines on pyelonephritis (acute): antimicrobial prescribing or prostatitis (acute): antimicrobial prescribing, basing antibiotic choice on recent culture and susceptibility results.

[A] See British National Formulary (BNF) for appropriate use and dosing in specific populations, for example, hepatic impairment and renal impairment.

[B] Doses given are by mouth using immediate-release medicines, unless otherwise stated.

[C] Check any previous urine culture and susceptibility results and antibiotic prescribing and choose antibiotics accordingly.

[D] Nitrofurantoin is not recommended for men with suspected prostate involvement because it is unlikely to reach therapeutic levels in the prostate.

[E] 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 (BNF, August 2018).

UTI=urinary tract infection; eGFR=estimated glomerular filtration rate

© NICE 2018. Urinary tract infection (lower): antimicrobial prescribing. Available from: www.nice.org.uk/guidance/ng109 All rights reserved. Subject to Notice of rights. NICE guidance is prepared for the National Health Service in England. All NICE guidance is subject to regular review and may be updated or withdrawn. NICE accepts no responsibility for the use of its content in this product/publication. See www.nice.org.uk/re-using-our-content/uk-open-content-licence for further details.

8. Know about possible options for preventing recurrent UTI

NICE Guideline (NG) 112 comments that some non-pregnant women may wish to try D-mannose as self-care treatment, or cranberry products, though the evidence for benefit of these is uncertain.5 People taking either product should be advised about the sugar content.5 Should this not help, consider vaginal oestrogens in post-menopausal women (unlicensed use).5 Should UTIs still recur, consider single-dose antibiotics when the patient is exposed to the known trigger.5 Finally, consider daily prophylactic antibiotics. For full details, including recommendations about when to refer and when to seek specialist advice, see NG112 on Urinary tract infection (recurrent): antimicrobial prescribing and the helpful 2-page visual summary.5

A note on preventative techniques

There is currently no convincing evidence for adapting behavioural and personal hygiene measures (for example, reduced fluid intake, habitual and post-coital delayed urination, wiping from front to back after defecation, douching and wearing occlusive underwear) to prevent recurrent UTIs in non-pregnant women.1

In pregnancy, a systematic review concluded that only hygiene measures (washing the genital area, voiding the bladder after intercourse, and wiping from front to back) were supported by evidence to be recommended in practice.6 Studies involving intake of cranberry juice, ascorbic acid, and a herbal product (‘Canephron N’) had limitations that cast doubt on their effectiveness; further improved studies are needed.6 However, these substances appear to be safe to use in pregnancy.5

9. Know the red flags for possible cancer

Refer people using a suspected cancer pathway referral (for an appointment within 2 weeks) for bladder cancer if they are:7

  • aged 45 and over and have:
    • unexplained visible haematuria without UTI or
    • visible haematuria that persists or recurs after successful treatment of UTI, or
  • aged 60 and over and have unexplained non‑visible haematuria and either dysuria or a raised white cell count on a blood test.

Consider non-urgent referral for bladder cancer in people aged 60 and over with recurrent or persistent unexplained UTI.7

Summary

Urinary tract infections are commonplace in general practice. Consider which risk group the patient falls into, their urinary tract history and co-morbidities. Strive to dipstick urine from affected males and pregnant women. Treat empirically but review antibiotic choice if no improvement after 48 hours and again after receiving culture results. Treat asymptomatic bacteriuria in pregnant women. Assess clinical severity when presenting with acute pyelonephritis and be alert to sepsis. Familiarise yourself with the NICE fast-track urological cancer pathway.

Dr Sonya Jey

Locum GP, West London

References

  1. Bonkat G, Bartoletti R, Bruyère F et al. European Association of Urology guideline: urological infections. EAU, 2019. Available at: uroweb.org/guideline/urological-infections/
  2. NICE. Urinary tract infection (lower): antimicrobial prescribing. NICE guideline 109. NICE, 2018. Available at: www.nice.org.uk/ng109
  3. Public Health England. Diagnosis of urinary tract infections: quick reference guide for primary care for consultation and local adaptation. PHE, 2019. Available at: www.gov.uk/government/publications/urinary-tract-infection-diagnosis
  4. NICE. Pyelonephritis (acute): antimicrobial prescribing. NICE guideline 111. NICE, 2018. Available at: www.nice.org.uk/ng111
  5. NICE. Urinary tract infection (recurrent): antimicrobial prescribing. NICE Guideline 112. Available at: www.nice.org.uk/ng112
  6. Ghouri F, Hollywood A, Ryan K. A systematic review of non-antibiotic measures for the prevention of urinary tract infections in pregnancy. BMC Pregnancy Childbirth 2018; 18: 99.
  7. NICE. Suspected cancer: recognition and referral. NICE Guideline 12. NICE, 2015 (updated 2017). Available at: www.nice.org.uk/ng12