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Acute pyelonephritis in pregnancy — MRCEM SBA MCQ

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EasyInfection and sepsisAcute pyelonephritis in pregnancyMRCEM SBA

A 28-year-old woman who is 23 weeks pregnant attends the emergency department with fever, dysuria and right loin pain. She has right costovertebral angle tenderness, and urine dipstick testing is positive for nitrites and leucocytes. Her temperature is 38.5°C, pulse 108/min and blood pressure 118/72 mmHg; she is alert. She has vomited repeatedly and cannot retain water despite an antiemetic. A midstream urine sample has been sent for culture, intravenous fluids are running, and she has no antibiotic allergy or previous resistant urinary isolates. Which initial antibiotic and disposition plan is most appropriate?

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

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Correct answer: B — Start intravenous cefuroxime and admit for obstetric assessment.

Fever, loin tenderness and supportive urine findings indicate acute pyelonephritis rather than a lower urinary tract infection. Pregnancy increases the concern for complications, while persistent vomiting makes oral treatment unreliable. NICE recommends considering hospital referral for pregnant patients and for those unable to take oral fluids or medicines. For a pregnant patient with pyelonephritis who is vomiting, its first-choice intravenous antibiotic is cefuroxime. Intravenous treatment should be reviewed by 48 hours, with a switch to an oral antibiotic when appropriate. ([nice.org.uk](https://www.nice.org.uk/guidance/ng111/chapter/recommendations)) A is tempting because cefalexin is NICE’s first-choice *oral* option in pregnancy, but she cannot retain it. C selects the appropriate antibiotic but discharges a patient who still needs parenteral treatment and inpatient assessment. D provides an intravenous drug and admission, but co-amoxiclav is not NICE’s first-choice empirical treatment in this setting; second-choice treatment warrants microbiology advice. E may suit some lower urinary infections, but nitrofurantoin does not achieve adequate renal-tissue concentrations for pyelonephritis and is also oral. ([nice.org.uk](https://www.nice.org.uk/guidance/ng111/chapter/recommendations))

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 — Summary of the evidence (2018) — https://www.nice.org.uk/guidance/NG111/chapter/summary-of-the-evidence