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Acute lower urinary tract infection in a man — MSRA MCQ

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ModerateUrinary Tract InfectionsAcute lower urinary tract infection in a manMSRA

A 67-year-old man presents with 24 hours of dysuria, urinary frequency and suprapubic discomfort. He has no fever, rigors, loin pain, nausea, vomiting, perineal pain or urinary retention. He is haemodynamically stable and can take oral medication. Abdominal examination is unremarkable, and there is no prostate tenderness on rectal examination. His eGFR is 58 mL/minute/1.73 m². He has a history of immediate anaphylaxis after amoxicillin. A urine culture 5 months ago grew Escherichia coli resistant to trimethoprim and susceptible to nitrofurantoin. He has not received antibiotics in the past 3 months. What is the most appropriate immediate management?

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Correct answer: B — Send a midstream urine sample and prescribe nitrofurantoin 100 mg modified-release twice daily for 7 days

This is an acute lower UTI in a man: dysuria, frequency and suprapubic discomfort are present, without fever, loin pain, vomiting, sepsis or features suggesting pyelonephritis. The absence of perineal pain and prostate tenderness makes acute bacterial prostatitis unlikely. NICE recommends an immediate antibiotic prescription for men with lower UTI and obtaining a midstream urine sample before antibiotics for culture and susceptibility testing. Nitrofurantoin is appropriate because his eGFR is above 45 mL/minute/1.73 m² and a recent culture supports susceptibility. In men, the recommended nitrofurantoin course is 7 days, rather than the 3-day regimen used for non-pregnant women. Trimethoprim would otherwise be a first-choice option, but his recent isolate was resistant. Ciprofloxacin is not indicated for uncomplicated lower UTI without suspected prostatic or upper-tract involvement; its use should be reserved where better-targeted agents are unsuitable. Deferring treatment pending culture is inappropriate because men with lower UTI should receive immediate treatment. Culture results should subsequently be reviewed, changing therapy if resistance is identified and symptoms are not improving.

Reference: Urinary tract infection (lower): antimicrobial prescribing (NG109), Recommendations (Published 31 October 2018; minor update May 2025) — https://www.nice.org.uk/guidance/ng109/chapter/Recommendations Urinary tract infection (lower): antimicrobial prescribing (NG109), Table 3: Antibiotics for men aged 16 years and over (Published 31 October 2018; minor update May 2025) — https://www.nice.org.uk/guidance/ng109/chapter/Recommendations Nitrofurantoin 50 mg capsules - Summary of Product Characteristics (Last updated 12 June 2025) — https://www.medicines.org.uk/emc/product/101005/smpc