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Transient PSA elevation associated with urinary tract infection — MSRA MCQ

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HardPSATransient PSA elevation associated with urinary tract infectionMSRA

A 56-year-old man attends 10 days after completing trimethoprim for a culture-confirmed Escherichia coli urinary tract infection. At presentation he had dysuria, fever, urinary frequency and perineal discomfort. These symptoms have resolved completely. He has no visible haematuria, bone pain or weight loss. A PSA test, taken on the day he first presented and before antibiotics were started, was 6.1 micrograms/L. He is of Black African-Caribbean family background and his father was diagnosed with prostate cancer aged 68 years. Digital rectal examination today shows a smooth, non-tender prostate with no focal abnormality. He is fit for radical treatment if clinically significant prostate cancer is identified. What is the most appropriate next step in prostate cancer assessment?

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

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Correct answer: A — Repeat the PSA 6 weeks after completion of antibiotic treatment, referring if it remains raised for his age

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

The PSA was measured during a symptomatic, culture-confirmed urinary tract infection, a recognised cause of transient PSA elevation. It should therefore not be used to trigger immediate cancer referral or MRI. UK guidance advises deferring PSA testing until at least 6 weeks after treatment for a UTI has been completed. His Black African-Caribbean family background and first-degree family history increase baseline prostate cancer risk, but neither overrides the need to obtain an interpretable post-infection PSA in the absence of a malignant-feeling prostate or other features suggesting advanced disease. B is attractive because 6.1 micrograms/L would otherwise be concerning, particularly with his risk factors; it would be appropriate if the PSA remained raised after the post-infectious interval or DRE were suspicious. C is too early, so residual inflammatory elevation may still confound interpretation. D bypasses the appropriate primary-care confirmation of a potentially spurious PSA result; mpMRI is generally the first-line secondary-care investigation after referral for suspected localised disease. E is inappropriate: finasteride may lower PSA and complicate interpretation, and should not be initiated to manage an unexplained PSA elevation before reassessment.

Reference: NHS: PSA test (Last reviewed 2 September 2024) — https://www.nhs.uk/tests-and-treatments/psa-test/ Right Decisions NHS Scotland: Prostate cancer (Date not stated) — https://www.rightdecisions.scot.nhs.uk/scottish-referral-guidelines-for-suspected-cancer/urological-cancers/prostate-cancer/ NICE NG131: Prostate cancer: diagnosis and management, MRI and biopsy recommendations (2019, current NICE guidance checked August 2026) — https://www.nice.org.uk/guidance/ng131/chapter/Recommendations