Common Anal Conditions · Version 2.0

Chapter 11 — Sexually Transmitted Infections, Proctitis, and Anorectal Sexual Health

Dr. Tamer Rushdy Elalfy · 12 min read

In this chapter

1. The Non-Judgemental Sexual History
2. Pathogens, Presentations, and Tests
3. Treatment (CDC 2021) [S]
4. When to Suspect LGV, HIV, Syphilis, or Disseminated Infection
5. Prevention and Anal Cancer Protection
6. Dangerous Mimics
7. Role-Targeted Action Boxes
The Patient in Front of You — Chapter 11 Mini-Case
Board-Style Question — Chapter 11
Ten-Item Rapid Revision Checklist — Chapter 11
Five Most Dangerous Mistakes — Chapter 11
Suggested Figure and Table Captions for the Medical Illustrator — Chapter 11

Purpose: ask every patient with anorectal symptoms about sexual exposure — kindly and routinely — because gonorrhoea, chlamydia (including LGV), syphilis, herpes, mpox, and HIV all present as “piles”, “fissures”, or “proctitis”.

🎨 INFOGRAPHIC / VISUAL BLUEPRINT — CHAPTER 11

Chapter colour palette: Cobalt Violet (#5B21B6) header bar, Lavender (#F5F3FF) panels, Midnight Violet (#2E1065) text.

Hero graphic: A private consultation scene (screen drawn, clinician seated at eye level) with a speech bubble containing a padlock; beside it a pathogen grid mapping each infection to its anorectal sign (discharge, ulcer, warts, rash, nodes), and a “treat before results” syringe-and-capsule icon for proctitis.

Icon set: Speech bubble with padlock (confidentiality), rectal swab tube, syringe (ceftriaxone), capsule (doxycycline), red ribbon (HIV), shield (vaccines), envelope (partner notification).

Bedside aphorism banner: “Ask everyone, judge no one, test every exposed site — and treat proctitis before the results come back.”

1. The Non-Judgemental Sexual History

Take the history in private, without relatives present, using neutral language and the patient’s own terms. Explain why you are asking: “I ask everyone with these symptoms about sex, because some infections look exactly like piles or a fissure.” Use a professional interpreter, never a family member. Documentation and reporting duties vary between countries — follow local law and professional confidentiality codes [L].

Table 11.1 — The “5 Ps” (CDC 2021)

Domain	Example question
Partners	“In the past 3 months, how many sexual partners have you had? Were they men, women, or both?”
Practices	“Have you had receptive anal sex (a partner’s penis, fingers, or objects in your anus)? Oral sex? Vaginal sex?”
Protection from STIs	“How often do you use condoms? Do you use HIV PrEP?”
Past history of STIs	“Have you ever been diagnosed with an STI? When were you last tested for HIV?”
Pregnancy intention	“Could you be pregnant? Are you trying to become pregnant?”

2. Pathogens, Presentations, and Tests

Table 11.2 — Infectious causes of anorectal symptoms

Infection	Typical anorectal presentation	Key test
Gonorrhoea	Proctitis: mucopurulent discharge, tenesmus, pain; often asymptomatic	Rectal NAAT
Chlamydia (non-LGV)	Mild proctitis or none	Rectal NAAT
Lymphogranuloma venereum (LGV, serovars L1–L3)	Severe proctocolitis: bloody discharge, tenesmus, ulceration, fever, inguinal nodes — can mimic Crohn’s disease	Rectal NAAT; LGV typing where available
Syphilis	Primary chancre (often painless, indurated ulcer — can mimic a fissure); secondary condylomata lata, rash on palms and soles	Treponemal and non-treponemal serology; lesion PCR where available
Herpes simplex (HSV)	Very painful vesicles or ulcers, severe proctitis, fever; may cause urinary retention or sacral radiculopathy	HSV PCR from lesion
Mpox	Painful anorectal lesions and proctitis, often with fever and lymphadenopathy	Mpox PCR from lesion
HPV	Anogenital warts; HSIL and cancer (Chapter 07)	Clinical; biopsy if atypical
HIV	Acute seroconversion (fever, rash, sore throat, nodes); co-infection with all of the above	Fourth-generation antigen/antibody test
Enteric (Shigella, Campylobacter, amoebiasis, C. difficile)	Bloody diarrhoea, cramps, proctocolitis	Stool culture or PCR (with susceptibility testing)

Test every exposed site (rectum, pharynx, urethra or vagina). Also test for HIV, syphilis, hepatitis B and C, check hepatitis A and B immunity, and offer a pregnancy test where relevant.

3. Treatment (CDC 2021) [S]

Table 11.3 — Adult treatment regimens (check national guidance [L])

Situation	Recommended regimen	Notes
Acute proctitis — empirical, before results	Ceftriaxone 500 mg IM single dose (1 g if ≥ 150 kg) plus doxycycline 100 mg orally twice daily for 7 days	Extend doxycycline to 21 days if LGV is suspected (bloody discharge, ulcers, or tenesmus with positive rectal chlamydia). Add HSV treatment if ulcers suggest herpes.
Gonorrhoea (uncomplicated)	Ceftriaxone 500 mg IM single dose	Some national guidelines use 1 g [L]. Retest at 3 months.
Rectal chlamydia	Doxycycline 100 mg orally twice daily for 7 days	Pregnancy: azithromycin 1 g orally single dose.
LGV	Doxycycline 100 mg orally twice daily for 21 days	Pregnancy: specialist regimen.
Primary, secondary, or early latent syphilis	Benzathine penicillin G 2.4 million units IM single dose	Penicillin allergy (not pregnant): doxycycline 100 mg twice daily for 14 days. Pregnancy: penicillin (desensitise if allergic).
First-episode genital or anal herpes	Valaciclovir 1 g orally twice daily for 7–10 days (or aciclovir 400 mg three times daily)	Severe proctitis or immunosuppression: specialist; IV aciclovir if severe.
Disseminated gonococcal infection	Admit; ceftriaxone 1 g IV daily	Fever, arthritis, tenosynovitis, pustular skin lesions.
Mpox	Supportive care; analgesia; stool softeners	Antivirals only via specialist or public-health pathways [U].
Shigella and other enteric infections	Guided by culture and susceptibility	Antimicrobial resistance is common [L].

ℹ️ AFTER EVERY DIAGNOSIS

Partner notification: treat or test partners; expedited partner therapy only where legal [L].

Abstain from sex for 7 days after treatment and until partners are treated.

Retest at 3 months after gonorrhoea, chlamydia, or trichomonas.

4. When to Suspect LGV, HIV, Syphilis, or Disseminated Infection

LGV: proctitis with bloody discharge, ulceration, fever, or nodes — especially in men who have sex with men; colitis that “looks like Crohn’s” in someone with sexual risk.
HIV: any new STI, recurrent STIs, acute febrile illness with rash and nodes, unusual or severe infections, or anal HSIL/cancer.
Syphilis: a painless anal ulcer, a rash on palms and soles, condylomata lata, or neurological, ocular, or hearing symptoms (urgent specialist review).
Disseminated gonococcal infection: fever with migratory arthritis, tenosynovitis, or pustular skin lesions — admit.

5. Prevention and Anal Cancer Protection

Condoms; HIV pre-exposure prophylaxis (PrEP) for people at ongoing risk.
Doxycycline post-exposure prophylaxis (doxy-PEP) [S]: 200 mg once, within 72 hours of condomless sex, offered after shared decision-making to men who have sex with men and transgender women with a bacterial STI in the past 12 months; maximum 200 mg in 24 hours; STI testing every 3–6 months (CDC 2024).
Vaccines: HPV (Chapter 07), hepatitis A and B, and mpox vaccine for eligible people per national programmes [L].
Anal cancer screening for eligible high-risk groups (IANS 2024; Chapter 07).

Algorithm 11.1 — Rapid STI and proctitis pathway

[ANORECTAL PAIN, DISCHARGE, TENESMUS, BLEEDING, OR ULCER]
|
+-- Private, non-judgemental sexual history (5 Ps)
|   + examine: ulcers, warts, discharge, groin nodes, rash
|
+-- Systemically unwell? (fever with arthritis or rash,
|   severe pain, urinary retention, sepsis)
|     -> same-day review; admit if DGI, severe HSV, or
|        sepsis; exclude abscess (Chapter 05)
|
+-- TEST: rectal NAAT (GC/CT; LGV typing if CT positive),
|   syphilis serology, HIV, HSV/mpox PCR from lesions,
|   stool tests if diarrhoea, hepatitis B/C, pregnancy
|
+-- PROCTITIS (discharge, tenesmus, pain)
|     -> treat NOW, before results (CDC 2021):
|        ceftriaxone 500 mg IM once + doxycycline 100 mg
|        twice daily 7 days (21 days if LGV suspected)
|        + valaciclovir if ulcers suggest herpes
|
+-- ULCER: painful or multiple -> HSV (or mpox)
|          painless or indurated -> syphilis
|          (biopsy if it does not heal: Chapter 07)
|
+-- ALWAYS: partner notification; abstain 7 days and
    until partners treated; PrEP/PEP review; vaccines;
    retest at 3 months

6. Dangerous Mimics

Table 11.4 — STI mimics and look-alikes

Looks like	Could be	Clue
Crohn’s proctitis	LGV	Sexual exposure, positive rectal chlamydia, inguinal nodes
Chronic fissure or anal cancer	Syphilitic chancre	Indurated, often painless ulcer; positive serology
Fissure or abscess	HSV or mpox	Multiple painful ulcers or vesicles; fever
Haemorrhoids or warts	Condylomata lata (secondary syphilis)	Moist, flat plaques; rash; positive serology
Simple warts	HSIL or anal cancer	Induration, ulceration, bleeding, HIV (Chapter 07)
IBD flare	Shigella or other enteric infection	Acute onset, contacts, positive stool PCR

7. Role-Targeted Action Boxes

🚑 ER DOCTOR ACTION BOX

Treat proctitis empirically after swabs; do not wait for results.

Severe HSV proctitis can cause urinary retention — scan the bladder.

Exposure within the last 72 hours? Assess for HIV post-exposure prophylaxis now (Chapter 12).

🩺 FAMILY MEDICINE / GP CLINIC BOX

Make the sexual history routine for anorectal complaints — and test all exposed sites.

Offer HIV testing to everyone tested for an STI; discuss PrEP, doxy-PEP (if eligible), and vaccines.

Book the 3-month retest at the treatment visit.

🏥 ER & WARD NURSE CARE AND SBAR BOX

Protect privacy: no relatives in the room for the history; offer self-collected swabs where validated.

Teach-back: medication course, abstinence period, and partner notification.

Flag safeguarding concerns for anyone under 18 or anyone who may be coerced or exploited.

💊 CROSS-SPECIALTY PRESCRIBING TRAP

Doxycycline is avoided in pregnancy — use azithromycin for chlamydia and seek specialist advice for LGV and syphilis.

Doxycycline: take with a full glass of water, sitting upright (oesophagitis); photosensitivity.

Haemorrhoid creams for proctitis delay the diagnosis.

⛔ NEVER DO THIS

Never treat discharge and tenesmus as “piles” without STI testing.

Never take a sexual history in front of relatives or use a family member as interpreter.

Never omit an HIV test when an STI is diagnosed or suspected.

Never make assumptions about sexual orientation, practices, or relationships.

📝 COMMON DOCUMENTATION ERROR

Judgemental or speculative language about sexual behaviour; record only what is clinically necessary.

No record of sites tested, partner-notification plan, or retest date.

📨 REFERRAL URGENCY BOX

Urgency	Clinical trigger	Who and how fast
🔴 EMERGENCY	Sepsis; disseminated gonococcal infection with meningitis or endocarditis features	Resuscitate; admit; infectious diseases
🔴 SAME-DAY	Severe HSV with urinary retention; DGI; exposure within 72 hours needing HIV PEP; minor at immediate risk	ER or sexual-health service; safeguarding
🟡 URGENT	Confirmed or suspected STI; non-healing ulcer	Sexual-health clinic within days; biopsy pathway (Chapter 07)
🟢 ROUTINE	PrEP, vaccination, screening	Sexual-health or primary care

The Patient in Front of You — Chapter 11 Mini-Case

🧑‍⚕️ THE PATIENT IN FRONT OF YOU

A 28-year-old man has had 5 days of rectal pain, bloody mucopurulent discharge, and tenesmus. A haemorrhoid cream has not helped. On private questioning he reports receptive anal sex with two male partners in the past month without condoms. He has tender left inguinal nodes; anoscopy shows proctitis with small ulcers.

Step 1 Recognise the syndrome: proctitis with ulceration and nodes — consider LGV, gonorrhoea, syphilis, and HSV.

Step 2 Test: rectal NAAT (with LGV typing), syphilis serology, HIV, HSV PCR from ulcers, hepatitis B and C.

Step 3 Treat today: ceftriaxone 500 mg IM plus doxycycline 100 mg twice daily for 21 days (LGV suspected); add valaciclovir if ulcers look herpetic.

Step 4 Prevent: partner notification, 7-day abstinence, PrEP referral, vaccines, retest at 3 months; discuss doxy-PEP at follow-up.

Board-Style Question — Chapter 11

A 32-year-old woman who is 16 weeks pregnant has a positive rectal chlamydia NAAT (non-LGV) and no other infections. What is the most appropriate treatment?

A. Doxycycline 100 mg twice daily for 7 days
B. Azithromycin 1 g orally as a single dose
C. Ceftriaxone 500 mg IM only
D. Defer treatment until after delivery

Answer and explanation

❌ A Doxycycline is avoided in pregnancy.
✅ B Correct. CDC 2021 recommends azithromycin 1 g single dose for chlamydia in pregnancy (amoxicillin is an alternative), with a test of cure about 4 weeks later.
❌ C Ceftriaxone treats gonorrhoea, not chlamydia.
❌ D Untreated chlamydia risks maternal and neonatal complications.

Ten-Item Rapid Revision Checklist — Chapter 11

Five Most Dangerous Mistakes — Chapter 11

⚠️ Prescribing haemorrhoid cream for STI proctitis.
⚠️ Diagnosing Crohn’s disease in a patient with LGV.
⚠️ Missing HIV because no test was offered.
⚠️ Prescribing doxycycline to a pregnant patient.
⚠️ Taking a sexual history in front of relatives and losing the patient’s trust.

Suggested Figure and Table Captions for the Medical Illustrator — Chapter 11

Figure 11.1. The private, non-judgemental consultation.
Figure 11.2. Pathogen-to-sign map: discharge, ulcers, warts, plaques, nodes.
Figure 11.3. Proctitis on anoscopy: gonococcal versus LGV ulcerative proctitis.
Table 11.1. The 5 Ps sexual history.
Table 11.2. Infectious causes of anorectal symptoms.
Table 11.3. Adult treatment regimens.
Table 11.4. STI mimics and look-alikes.
Algorithm 11.1. Rapid STI and proctitis pathway.