Evaluation and Management of Green Rectal Discharge

Diagnostic Approach

Green discharge specifically suggests purulent infection, most commonly from sexually transmitted organisms including Neisseria gonorrhoeae, Chlamydia trachomatis, or mixed anaerobic bacteria from an anorectal abscess, according to the World Journal of Emergency Surgery 1
Perform digital rectal examination to assess for fluctuance suggesting abscess, though imaging should precede examination if sharp foreign body is suspected, as recommended by the World Journal of Emergency Surgery 2
Request complete blood count and inflammatory markers if systemic infection or abscess is suspected, as suggested by the World Journal of Emergency Surgery 2

Plain X-ray of abdomen/pelvis can identify free air suggesting perforation, according to the World Journal of Emergency Surgery 2
CT or MRI defines abscess anatomy and extent, guiding drainage approach, as recommended by the World Journal of Emergency Surgery 1
Ultrasound may identify perianal abscesses but is operator-dependent, according to the World Journal of Emergency Surgery 1

Add metronidazole if anaerobic infection suspected based on foul odor or mixed flora, as suggested by the World Journal of Emergency Surgery 1
Incision and drainage is the definitive treatment for anorectal abscess; timing depends on severity of sepsis, according to the World Journal of Emergency Surgery 1
Emergent drainage required if patient has sepsis, severe sepsis, septic shock, immunosuppression, diabetes, or diffuse cellulitis, as recommended by the World Journal of Emergency Surgery 1
Administer empiric broad-spectrum antibiotics covering aerobic and anaerobic organisms due to risk of bacterial translocation, as suggested by the World Journal of Emergency Surgery 1, 2

Do not delay abscess drainage for further testing; inadequate or delayed drainage leads to recurrence rates up to 44%, according to the World Journal of Emergency Surgery 1