Proctitis

Proctitis is inflammation of the rectal mucosa, with diverse infectious, inflammatory and ischaemic causes.

• Infectious: sexually transmitted organisms (Neisseria gonorrhoeae, Chlamydia trachomatis including LGV serovars, Treponema pallidum, herpes simplex virus, mpox), Shigella, Campylobacter, Entamoeba histolytica, cytomegalovirus in the immunosuppressed, Clostridioides difficile rarely.
• Inflammatory: ulcerative proctitis (limited disease), Crohn disease, eosinophilic proctitis, diversion proctitis, microscopic colitis variants.
• Other: radiation, ischaemic, drug induced (NSAID suppositories), trauma, foreign body, allergic proctocolitis in infants.
• Ulcerative proctitis accounts for about 30% of ulcerative colitis, and 10 to 30% extend proximally.
• Receptive anal intercourse is the main risk factor for infectious proctitis in men who have sex with men.

• Rectal bleeding, mucopurulent discharge, tenesmus, urgency, rectal pain, feeling of incomplete evacuation.
• Constipation or frequent small volume stools in distal disease.
• Systemic features are mild, except in invasive infection (fever, inguinal lymphadenopathy in LGV).
• Anal ulcers suggest herpes, syphilis, or Crohn disease.

• Sexual history, medications, radiation, travel.
• Proctoscopy or flexible sigmoidoscopy with biopsy: mucosal erythema, friability, ulcers, exudate.
• Microbiology: rectal NAAT for gonorrhoea and chlamydia (and LGV genotyping), HSV PCR, syphilis serology, stool culture and PCR, ova and cysts, amoebic serology, CMV immunohistochemistry on biopsy, mpox PCR.
• HIV and hepatitis testing.
• Faecal calprotectin; histology for chronic inflammatory changes, granulomas, eosinophils.

Infectious

• Gonorrhoea: ceftriaxone 1 g IM single dose. Chlamydia: doxycycline 100 mg twice daily for 7 days.
• LGV proctitis: doxycycline 100 mg twice daily for 21 days.
• Syphilis: benzathine penicillin G 2.4 million units IM.
• Herpes: valaciclovir 1 g twice daily for 7 to 10 days.
• Amoebiasis: metronidazole 750 mg three times daily for 7 to 10 days, then paromomycin 25 to 35 mg/kg/day in 3 doses for 7 days.
• CMV: ganciclovir 5 mg/kg IV every 12 hours, then valganciclovir 900 mg twice daily.
• Partner notification, HIV pre exposure prophylaxis counselling, and condoms.

Ulcerative proctitis

• Mesalazine suppository 1 g nightly (remission in 70 to 80%), with enema 1 to 4 g for extension. Add oral mesalazine 2 to 4 g daily.
• Corticosteroid foam (hydrocortisone, budesonide 2 mg/dose) for non responders; oral prednisolone 40 mg for severe disease.
• Refractory disease: azathioprine, vedolizumab, anti TNF, or tofacitinib, same as ulcerative colitis.

Others

• Diversion proctitis: short chain fatty acid enemas, corticosteroid enemas, restoration of continuity.
• Eosinophilic proctitis: topical budesonide, elimination diet.
• Radiation proctitis: sucralfate, argon plasma coagulation, formalin.