01Approach to the Critical Patient/attcp58

Immediate priorities

›Hemorrhage and hemodynamic threats

›Active rectal bleeding with hemodynamic instability

›SBP < 90 mmHg

›HR > 120 beats/min

›Resuscitation triggers

›Large bore IV access and fluid bolus

›Type and screen for significant hemorrhage

›If hemodynamically unstable with ongoing rectal bleeding, activate GI and surgery consults emergently

›Transfusion threshold Hgb < 70 g/L or hemodynamic instability

›NPO and IV access preparation for endoscopy

›Sepsis and systemic infection threats

›Acute severe colitis criteria (Truelove and Witts)

›>= 6 bloody stools per day

›Fever >= 37.8 C

›HR > 90 beats/min

›Hgb < 105 g/L

›ESR > 30 mm/hr or CRP > 30 mg/L

›Sepsis screen

›High fever >= 38.5 C with rectal symptoms

›Peritoneal signs suggesting perforation

›If acute severe colitis or sepsis, IV corticosteroids and urgent GI consultation

›Hydrocortisone 100 mg IV every 8 hours

›Blood cultures prior to antibiotics

›Surgical emergency screen

›Perforation risk

›Rigid abdomen or guarding

›Free air on imaging

02History/hx79

Presentation pattern

›Core anorectal syndrome

›Rectal bleeding

›Color and volume assessment

›Clot passage

›Tenesmus and urgency

›Sensation of incomplete evacuation

›Urgency preceding defecation

›Anorectal discharge

›Purulent (gonococcal, chlamydial)

›Mucoid (ulcerative proctitis)

›Anorectal pain

›Severe pain suggesting HSV or LGV

›Mild discomfort in gonorrhea (often asymptomatic)

›Onset and chronology

›Acute onset < 4 to 6 weeks favors infectious etiology

›Recent receptive anal intercourse

›New sexual partner

›Chronic relapsing course suggests IBD

›Prior episodes of rectal bleeding and urgency

›Known IBD diagnosis

Sexual and exposure history

›Sexual history (critical for all proctitis)

›Receptive anal intercourse

›Strongest risk factor for infectious proctitis

›Oral-anal, digital-anal, genital-anal contact

›Number of partners and condom use

›Condomless intercourse increases risk

03Physical Exam/exam58

Vitals and general

›Hemodynamic stability assessment

›Blood pressure and heart rate

›SBP < 90 mmHg triggers resuscitation

›HR > 120 beats/min suggests hemorrhage or sepsis

›Temperature

›Fever >= 38.5 C suggests systemic infection

›High fever with tachycardia meets sepsis criteria

›General appearance

›Toxicity suggesting acute severe colitis

›Pallor suggesting significant hemorrhage

Abdominal and perianal exam

›Abdominal assessment

›Left lower quadrant tenderness

›Ulcerative proctitis/colitis

›Infectious proctocolitis

›Peritoneal signs

›Guarding and rebound suggesting perforation

›Abdominal distension suggesting toxic megacolon

›Perianal inspection

›Vesicles or pustules

›HSV or mpox

›Perianal distribution

›Ulcers or fissures

›Syphilitic chancre (may be painless)

›LGV or HSV ulcers (painful)

›Condylomata

›HPV co-infection

04Differential Diagnosis/ddx51

Infectious (cannot miss)

›STI-related proctitis

›Gonococcal proctitis (N. gonorrhoeae)

›ICD-10 A54.6

›Often asymptomatic; purulent discharge when symptomatic

›Chlamydial proctitis (C. trachomatis serovars D-K)

›ICD-10 A56.3

›Mild symptoms; MPC-like discharge

›Lymphogranuloma venereum (LGV serovars L1-L3)

›ICD-10 A55

›Severe ulcerative proctitis with tenesmus and bloody discharge

›Syphilitic proctitis (T. pallidum)

›ICD-10 A51.0

›Mass-like presentation mimicking rectal carcinoma

›HSV proctitis (HSV-1 or HSV-2)

›ICD-10 A60.1

›Severe anorectal pain, vesicles, urinary retention

›Mpox proctitis

›ICD-10 B04

›Vesiculopustular perianal lesions, inguinal lymphadenopathy

Inflammatory bowel disease

›IBD spectrum

›Ulcerative proctitis (UC limited to rectum)

›ICD-10 K51.20

›Chronic relapsing rectal bleeding and urgency

›Crohn's proctitis

›ICD-10 K50.10

›Perianal fistulae, skip lesions, granulomas on biopsy

05Laboratory Tests/lt60

Infectious workup

›STI-directed testing (CDC guidelines)

›Rectal swab NAAT for N. gonorrhoeae and C. trachomatis

›Preferred over culture for sensitivity

›Differentiates LGV serovars when LGV-specific NAAT available

›HSV NAAT from rectal swab or lesion swab

›Preferred over Tzanck smear

›Typing (HSV-1 vs HSV-2) guides prognosis

›Syphilis serology

›RPR or VDRL as non-treponemal screening

›Confirmatory treponemal test (FTA-ABS or TPPA)

›Gram stain of anorectal exudate

›PMNs with gram-negative intracellular diplococci suggest gonorrhea

›Limited sensitivity compared to NAAT

›Mpox PCR (rectal swab)

›Vesiculopustular lesions trigger testing

›Public health notification required

›M. genitalium NAAT

›Persistent symptoms after standard STI therapy

›Resistance testing if positive

›HIV and immunology

›HIV 4th-generation Ag/Ab test

›All patients with STI-related proctitis (CDC recommendation)

›If reactive, quantitative RNA viral load and CD4 count

›CD4 count if HIV-positive

›CD4 < 200 cells/uL increases CMV and disseminated HSV risk

Inflammatory and IBD labs

›Systemic inflammation markers

06Diagnostic Tests/dt68

Scoring Systems

›Acute severe colitis risk stratification

›Truelove and Witts criteria

›>= 6 bloody stools/day

›Temperature >= 37.8 C

›Heart rate > 90 beats/min

›Hgb < 105 g/L

›ESR > 30 mm/hr

›Meets criteria: admission and IV corticosteroids

›Mayo Score for ulcerative colitis severity

›Stool frequency subscore (0-3)

›Rectal bleeding subscore (0-3)

›Physician global assessment (0-3)

›Endoscopic subscore (0-3)

›Remission defined as total score 0-2 with no subscore > 1

›Oxford criteria for IV steroid failure prediction

›CRP > 45 mg/L on day 3 with > 3 stools/day

›Predicts 85% colectomy rate at that threshold

MRI

›MRI for anorectal and pelvic assessment

›Pelvic MRI indications

›Perianal fistula mapping in Crohn's proctitis

›Abscess localization

›Rectal wall invasion assessment when malignancy suspected

›MRI findings in proctitis

›Rectal wall thickening and submucosal edema

›Mesorectal fat stranding

›Perirectal lymphadenopathy

07Disposition/dispo51

Admission criteria

›Indications for inpatient admission

›Hemodynamic instability or significant hemorrhage

›Transfusion requirement

›Ongoing hemodynamic compromise

›Acute severe ulcerative colitis (Truelove and Witts criteria)

›IV corticosteroids initiation

›Rescue therapy planning

›Systemic toxicity or sepsis

›High fever with tachycardia

›Peritoneal signs

›Urinary retention

›HSV proctitis with sacral radiculopathy

›Urologic management

›Inability to tolerate oral intake or medications

›Dehydration with severe vomiting

›Suspected perforation, abscess, or toxic megacolon

›Surgical consultation and ICU monitoring

Discharge criteria

›Outpatient management appropriate when

›Hemodynamically stable, tolerating PO

›HR < 100 beats/min and SBP >= 90 mmHg

›No hematemesis or large volume rectal bleeding

›Uncomplicated infectious proctitis

›Empiric antibiotic therapy initiated

›Reliable follow-up plan in place

›Mild ulcerative proctitis

›Topical mesalamine initiated

08Treatment/t84

Empiric therapy for infectious proctitis

›First-line CDC-recommended empiric regimen

›Ceftriaxone plus doxycycline

›Ceftriaxone 500 mg IM single dose (covers gonorrhea)

›Doxycycline 100 mg PO twice daily for 7 days (covers chlamydia)

›Extend doxycycline to 21 days if LGV suspected

›LGV suspicion triggers

›Bloody discharge, perianal or mucosal ulcers, severe tenesmus

›Positive rectal chlamydia NAAT with severe symptoms

›Add HSV coverage when painful perianal ulcers or vesicles present

›Valacyclovir 1 g PO twice daily for 7 to 10 days

›Alternative: acyclovir 400 mg PO three times daily for 7 to 10 days

›Pathogen-directed therapy after testing

›Gonococcal proctitis

›Ceftriaxone 500 mg IM single dose (or 1 g if weight > 150 kg)

›If cephalosporin allergy, infectious disease consultation

›Test-of-cure at 7 to 14 days

›Chlamydial proctitis (non-LGV)

›Doxycycline 100 mg PO twice daily for 7 days

›Alternative: azithromycin 1 g PO single dose (less effective for rectal)

›LGV proctitis

›Doxycycline 100 mg PO twice daily for 21 days

›Class I recommendation per CDC STI Guidelines 2021

›HSV proctitis

›First episode: valacyclovir 1 g PO twice daily for 7 to 10 days

›Severe or immunocompromised: acyclovir 5 mg/kg IV every 8 hours

›Suppressive therapy for recurrent HSV

›Syphilitic proctitis

›Primary: benzathine penicillin G 2.4 million units IM single dose

›Late or unknown duration: benzathine penicillin G 2.4 million units IM weekly for 3 doses

›Penicillin allergy: doxycycline 100 mg PO twice daily for 14 days

›Mpox proctitis

›Supportive care for most cases

›Tecovirimat for severe or immunocompromised patients

›Public health notification and contact tracing

Ulcerative proctitis treatment

›First-line therapy

›Mesalamine (5-ASA) suppository

›1 g rectally once daily at bedtime

›Strong recommendation per ACG Clinical Guideline 2025

›Symptoms may take up to 8 weeks to fully resolve

›Topical corticosteroid alternative when 5-ASA not tolerated

›Hydrocortisone foam 90 mg rectally once or twice daily

›Beclomethasone suppository as alternative

›Refractory ulcerative proctitis

›Second-line options

›Tacrolimus suppository for topical 5-ASA refractory disease

›Oral budesonide MMX 9 mg once daily for 8 weeks

›Escalation with GI consultation

›Immunomodulators (azathioprine, 6-mercaptopurine)

›Biologics (vedolizumab, anti-TNF agents)

›Acute severe ulcerative colitis (inpatient)

›IV corticosteroids

›Hydrocortisone 100 mg IV every 8 hours

›Methylprednisolone 60 mg IV daily as alternative

›Response assessment at 72 hours

›Rescue therapy if no response at 72 hours

›Infliximab 5 mg/kg IV (Class I recommendation)

›Ciclosporin 2 to 4 mg/kg/day IV

›Colectomy planning with surgical team

Radiation proctitis treatment

›Mild to moderate radiation proctitis

›Sucralfate retention enemas

›2 g in 20 mL water twice daily

›Moderately effective for rectal bleeding

›Antidiarrheals for symptom control

›Loperamide 2 to 4 mg PO up to 4 times daily

›Stool bulking agents

›Refractory radiation proctitis bleeding

›Argon plasma coagulation (APC)

›Effective short-term hemostasis

›Gastroenterology or surgery intervention

›Topical 4% formalin application

›Comparable efficacy to APC

›Specialist administration required

›Hyperbaric oxygen therapy

›Promotes tissue healing in chronic radiation injury

›20 to 40 sessions typically required

›Surgery reserved for hemorrhage, obstruction, fistula, or perforation

›ASCRS Clinical Practice Guidelines 2018

Partner management and prevention

›STI partner notification

›All sexual partners in the preceding 60 days

›Partner notification and treatment for gonorrhea and chlamydia

›Syphilis: partners within 3 months (primary), 6 months (secondary)

›PrEP counseling for HIV-negative MSM at high risk

›Tenofovir/emtricitabine once daily

›STI testing every 3 months on PrEP

09Special Populations/sp48

Pregnancy

›Pregnancy-specific considerations

›STI proctitis management in pregnancy

›Ceftriaxone 500 mg IM single dose safe in pregnancy

›Doxycycline contraindicated after first trimester (use azithromycin 1 g PO or amoxicillin)

›Benzathine penicillin G safe for syphilis treatment

›HSV in pregnancy

›Acyclovir 400 mg PO three times daily safe

›Risk of neonatal HSV transmission if active lesions at delivery

›Obstetric consultation required

›IBD management in pregnancy

›Mesalamine generally safe throughout pregnancy

›Avoid methotrexate (teratogenic)

›Biologics may be continued with specialist guidance

›Fetal monitoring

›Viable gestation monitoring when hemodynamically unstable

›Maintain maternal oxygenation and perfusion

Geriatric

›Older adult considerations

›Atypical presentation

›Reduced fever response may mask systemic infection

›Delirium or functional decline as presenting symptom

›Higher radiation proctitis prevalence

›Prior prostate or gynecologic malignancy treatment

›Chronic proctitis more common than acute infectious

›Medication safety in older adults

›Renal dose adjustment for renally cleared drugs

›Avoid fluoroquinolones due to tendinopathy and QT risk

10Background/b72

Epidemiology

›Incidence and prevalence

›Infectious proctitis

›Incidence rising globally; MSM most affected group

›Gonorrhea rectal infection: 25 to 40% of MSM with gonorrhea

›LGV proctitis increasing in MSM in Europe and North America

›Ulcerative proctitis

›30 to 50% of UC cases are limited to the rectum at presentation

›Annual incidence 6 to 8 per 100,000 in Western countries

›15 to 30% progress to more extensive colitis over 10 years

›Radiation proctitis

›Acute: up to 75% of patients receiving pelvic radiation

›Chronic radiation proctopathy: 5 to 20% of pelvic radiation recipients

›Highest risk with prostate, cervical, and rectal cancer treatment

›Pouchitis

›Cumulative rate ~50% at 10 years post-ileal pouch-anal anastomosis

›Most common complication of restorative proctocolectomy

Pathophysiology

›Infectious proctitis mechanisms

›STI pathogens

›N. gonorrhoeae invades rectal columnar epithelium causing purulent exudate

›C. trachomatis LGV serovars invade submucosa causing ulcerative proctitis

›HSV causes cytopathic mucosal destruction with vesicle formation

›T. pallidum causes granulomatous inflammation mimicking malignancy

›Mpox proctitis

›Direct mucosal infection after anal or perianal inoculation

›Vesiculopustular lesions progressing to ulceration

›Inflammatory bowel disease mechanisms

›Ulcerative proctitis

›Dysregulated mucosal immune response to luminal microbiota

›Predominantly Th2-mediated inflammation with IL-4 and IL-13

›Mucosal ulceration limited to rectum with proximal margin demarcation

›Goblet cell depletion and crypt architectural distortion on biopsy

›Disease extension risk

›15 to 30% extend proximally over 10 years

›Extension increases colorectal cancer risk proportional to extent

›Radiation proctitis mechanisms

›Acute phase (within 6 weeks)

›Direct DNA damage to rapidly dividing crypt cells

›Mucosal sloughing and inflammatory infiltrate

›Chronic phase (months to years)

›Obliterative endarteritis causing ischemic mucosal injury

›Progressive fibrosis and telangiectasia formation

›Rectal bleeding from friable telangiectatic vessels

Therapeutic Considerations

›Antibiotic stewardship in STI proctitis

›Empiric therapy rationale

›Treat gonorrhea and chlamydia empirically given co-infection rates

›Await pathogen-specific results to narrow therapy

›Resistance patterns

›N. gonorrhoeae ciprofloxacin resistance > 20% in most regions

›Cephalosporin-resistant gonorrhea emerging; confirm susceptibility

›Treatment failure assessment

›Persistent symptoms after 7 days warrants M. genitalium testing

›Consider doxycycline-refractory LGV if extending therapy

›IBD treatment principles

›Topical vs systemic therapy preference

›Topical mesalamine superior to oral for isolated proctitis

›Combination topical and oral 5-ASA for refractory disease

›Avoid systemic steroids for maintenance (side-effect profile)

›Biologic escalation trigger

›Failure of two adequate courses of topical therapy

›Systemic symptoms or complications at presentation

›Colorectal cancer surveillance

›Colonoscopy starting 8 years after IBD diagnosis

›Every 1 to 3 years depending on risk factors

›Radiation proctitis management principles

›Conservative first approach

›Mild symptoms: observation and dietary modification

›Progression: sucralfate enemas before procedural intervention

›Procedural escalation

›APC preferred first-line endoscopic therapy for bleeding telangiectasias

›Hyperbaric oxygen for refractory cases or those with poor endoscopic access

›Surgical last resort

›Diverting colostomy or proctectomy for uncontrolled hemorrhage or fistula

11Patient Discharge Instructions/pdi28

copy discharge instructions

›Proctitis home care instructions

›Take all antibiotics exactly as prescribed until the course is complete

›Do not share medications

›Complete the full course even if symptoms improve

›Mesalamine suppository instructions

›Insert at bedtime and retain for as long as possible

›Continue daily even when feeling better; symptoms may take 4 to 8 weeks to fully resolve

›Avoid sexual contact until treatment is complete and symptoms have resolved (infectious proctitis)

›All sexual partners should be notified and treated

›Hydration and rest

›Drink plenty of fluids if diarrhea is present

›Low-residue diet during flare if symptoms severe

›Warning signs to return to the emergency department

›Passing large amounts of blood rectally or blood clots

›Severe weakness, dizziness, or near-fainting

›High fever (temperature > 38.5 C) with chills or feeling severely unwell

›Inability to urinate (may occur with HSV proctitis)

›Severe abdominal pain or hard distended abdomen

›New skin lesions spreading or worsening

›Concern for mpox or disseminated infection

›Inability to tolerate fluids or medications

›Follow-up instructions

›Return for STI test results in 7 to 14 days

›Confirm treatment success and recheck for other infections

›Ensure partners have been treated

›Gastroenterology follow-up in 4 to 8 weeks for IBD or radiation proctitis

›Colonoscopy may be required for definitive diagnosis

12References/r27

Guidelines and key sources

›STI management guidelines

›CDC Sexually Transmitted Infections Treatment Guidelines 2021 (Workowski et al, MMWR 2021)

›Primary reference for gonorrhea, chlamydia, LGV, HSV, syphilis proctitis management

›IDSA/ASM Microbiology Laboratory Guide for Infectious Disease Diagnosis 2024

›NAAT testing standards and rectal swab recommendations

›IDSA Opportunistic Infections Guidelines in HIV 2025

›CMV and HSV management in HIV-positive patients

›IBD guidelines

›ACG Clinical Guideline Update: Ulcerative Colitis in Adults 2025 (Rubin et al, Am J Gastroenterol)

›Mesalamine suppository as first-line for ulcerative proctitis

›AGA Clinical Practice Guidelines on Mild-to-Moderate Ulcerative Colitis 2019 (Ko et al, Gastroenterology)

›Topical vs systemic therapy recommendations

›Radiation proctitis guidelines

›ASCRS Clinical Practice Guidelines for Treatment of Chronic Radiation Proctitis 2018 (Paquette et al, Dis Colon Rectum)

›APC, sucralfate, hyperbaric oxygen, and surgical indications

›Key reviews

›McNeil CJ et al. Proctitis: An Approach to the Symptomatic Patient. Med Clin North Am 2024

›Hall R et al. Separating Infectious Proctitis From IBD. Microorganisms 2024

›Wu XR et al. Pathogenesis, Diagnosis, and Management of Ulcerative Proctitis, Chronic Radiation Proctopathy, and Diversion Proctitis. Inflamm Bowel Dis 2015

›Coding references

›ICD-10 codes for proctitis spectrum

›K62.89 Other specified diseases of rectum (proctitis NOS)

›K51.20 Ulcerative proctitis without complications

›A54.6 Gonococcal infection of anus and rectum

›A56.3 Chlamydial infection of anus and rectum

›A55 Chlamydial lymphogranuloma (venereum)

›K62.7 Radiation proctitis

Evidence & Review

Evidence & Review