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Acute pyelonephritis in pregnancy — MSRA MCQ

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HardUrinary Tract InfectionsAcute pyelonephritis in pregnancyMSRA

A 31-year-old woman who is 24+2 weeks pregnant presents with 18 hours of dysuria, urinary frequency, rigors and left-sided loin pain. She has a temperature of 38.5°C, heart rate 102 beats/minute and blood pressure 118/72 mmHg. She is alert, is drinking normally and has not vomited. Examination shows left costovertebral-angle tenderness. There is no uterine tenderness, vaginal bleeding or uterine activity. Her eGFR is 94 mL/minute/1.73 m². She has no drug allergies. A midstream urine specimen can be obtained before treatment. A urine culture 5 months ago grew Escherichia coli resistant to trimethoprim and susceptible to cefalexin and co-amoxiclav. She has not received antibiotics in the previous 3 months. What is the most appropriate immediate management plan?

Educational content. Not a substitute for clinical judgement or local policy.

Reveal the answer and explanation

Correct answer: A — Send a midstream urine sample, start cefalexin 500 mg three times daily for 7 to 10 days, and seek same-day obstetric or secondary-care advice

Explanation lettering: C = shown as A · D = shown as B · B = shown as C · E = shown as D · A = shown as E

This is acute pyelonephritis rather than uncomplicated lower UTI: fever, rigors and unilateral costovertebral-angle tenderness indicate upper urinary tract involvement. A urine sample should be obtained before antibiotics, but treatment should not be delayed while awaiting culture. She is haemodynamically stable, can drink and take oral medication, and has no features requiring immediate intravenous therapy; therefore an oral antibiotic is appropriate initially. For pregnant people with acute pyelonephritis, NICE recommends oral cefalexin as the first-choice oral regimen, with a 7- to 10-day course. Pregnancy is also a specific indication to consider referral or specialist advice, even where the patient is currently suitable for oral treatment. Same-day obstetric or secondary-care advice is therefore appropriate. A is wrong because nitrofurantoin is a lower-UTI antibiotic and is not appropriate for suspected pyelonephritis. B inappropriately delays treatment of a potentially ascending infection. D would be appropriate if she were vomiting, unable to take oral treatment, severely unwell or septic, none of which applies. E is plausible because the previous isolate was susceptible, but co-amoxiclav for pyelonephritis should be used only when current culture results are available and demonstrate susceptibility; cefalexin is the recommended empiric oral choice in pregnancy.

Reference: NICE NG111: Pyelonephritis (acute): antimicrobial prescribing — Recommendations (31 October 2018) — https://www.nice.org.uk/guidance/NG111/chapter/recommendations NICE NG111: Pyelonephritis (acute): antimicrobial prescribing — Recommendations (31 October 2018) — https://www.nice.org.uk/guidance/NG111/chapter/recommendations NICE NG111: Pyelonephritis (acute): antimicrobial prescribing — Recommendations (31 October 2018) — https://www.nice.org.uk/guidance/NG111/chapter/recommendations