Sexual Health

Epididymo-orchitis

Epididymo-orchitis is acute inflammation of the epididymis with or without testicular involvement, usually from ascending sexually transmitted or urinary pathogens; the first decision is whether the acute scrotum could be testicular torsion, because imaging and antibiotics must never delay urgent exploration.

In a nutshell

Epididymo-orchitis is acute scrotal inflammation usually caused by ascending sexually transmitted or urinary pathogens. The critical first step is to exclude testicular torsion, because Doppler ultrasound must not delay exploration. Test for chlamydia, gonorrhoea and urinary pathogens, treat empirically according to risk and current safety guidance, give analgesia and scrotal support, manage partners when an STI is confirmed, and review early if symptoms worsen or fail to improve.

Classic presentation

An adult has unilateral scrotal pain and swelling with a tender epididymis, dysuria or urethral discharge and a several-hour-to-day course; the clinician actively assesses torsion before starting antibiotics.

Key points

Sexually transmitted pathogens are more likely with recent sexual exposure, while enteric pathogens are more likely with urinary symptoms, instrumentation, catheterisation, urinary-tract abnormality or insertive anal intercourse; age is only a guide.
Sudden severe pain, nausea, abnormal testicular lie or an absent cremasteric reflex raises concern for torsion, but no bedside sign reliably excludes it.
If torsion is clinically possible, urgent exploration takes priority over ultrasound, urine tests and antibiotics.
For probable sexually acquired disease, use current gonorrhoea-inclusive treatment plus an appropriate chlamydia course, checked against current BNF and local policy.
Enteric pathways may include a fluoroquinolone in BASHH guidance, but MHRA now restricts systemic fluoroquinolones to situations where other recommended antibiotics are inappropriate.
Mumps orchitis is viral and supportive; persistent or uropathogen-confirmed disease needs reassessment and often urology evaluation.

First-line investigation

Immediate torsion-focused examination plus first-pass urine or urethral NAAT for chlamydia and gonorrhoea, urine dipstick/culture and Doppler ultrasound only when uncertainty or complications justify it without delaying surgery.

Management

Treat the acute scrotum as torsion until safely excluded

Any clinically possible torsion requires immediate urological exploration; do not let ultrasound, NAAT or antibiotics delay the decision.¹

Test and start empirical treatment

Obtain STI and urine tests without delaying treatment, then choose ceftriaxone plus doxycycline for likely sexually acquired disease or a culture- and safety-guided enteric regimen when that pathway is more likely.^1,2,5,6

Relieve pain and manage sexual-health risk

Give analgesia, rest and scrotal support; arrange partner testing and treatment when an STI is confirmed and advise abstinence until the relevant treatment and partner management are complete.^1,5

Separate viral, atypical and resistant pathways

Manage mumps supportively and follow notification guidance; consider tuberculosis, BCG-related disease, brucellosis, vasculitis or medicine-related disease when the history or response is atypical.^1,3,4

Review early and refer urinary-pathogen disease

Reassess worsening or non-improving disease for torsion, abscess, infarction, tumour or incorrect pathogen; refer culture-confirmed uropathogen disease to urology to assess structural or obstructive urinary disease.^1,8

Exam traps

Do not let a positive urine test or a reassuring bedside sign distract from possible torsion; urgent exploration takes priority.
Doppler ultrasound can be false-negative and must not delay surgery when torsion is clinically suspected.
Doxycycline alone does not cover gonorrhoea; use the current gonorrhoea-inclusive regimen when indicated.
Do not prescribe a fluoroquinolone casually: MHRA restricts systemic use to situations where other recommended antibiotics are inappropriate.
A confirmed urinary pathogen in an adult warrants assessment for urinary-tract obstruction or structural abnormality.
Mumps orchitis is viral, and bilateral disease can impair fertility; antibiotics do not treat it.

Illustrations

Scrotal Doppler ultrasound in epididymo-orchitisA colour Doppler ultrasound of the scrotum showing enlargement and increased vascularity of the epididymis in acute epididymitis.Mikael HÃ¤ggstrÃ¶m, M.D. Author info, Wikimedia Commons · CC0

Key sources

This page is exam revision material, not medical advice, and must not be used for patient care. Always check drug doses against the BNF and current guidance. Full disclaimer.