Anorectal problems

Objectives

To provide clear, practical guidance for the assessment and initial management of rectal bleeding and common perianal conditions within the deployed military environment, and to identify red-flag features requiring escalation or evacuation.

Scope

These guidelines are for deployed clinicians who manage patients who require treatment of the following anorectal pathologies: 

Rectal bleeding

Haemorrhoids

Anal fissure

Perianal abscess

Anal fistula

Rectal prolapse

Audience

This guideline is intended for the use of registered healthcare professionals fulfilling a general role in a forward medical location or in an Emergency Department on deployed operations.

Initial Assessment & Management

Assessment & management of rectal bleeding and common perianal conditions

1. Rectal Bleeding

Background

Rectal bleeding is common in deployed personnel, often related to constipation, straining and dietary factors. It is usually benign but may rarely indicate significant pathology such as Inflammatory Bowel Disease (IBD) or colorectal malignancy.

Red Flags

Presence of any red flag warrants consideration for referral or evacuation:

  • Unintentional weight loss
  • Iron-deficiency anaemia
  • Change in bowel habit
  • Age >50 with new-onset bleeding
  • Family history of colorectal cancer
  • Persistent anorectal pain (not typical of haemorrhoids)

Assessment

History: colour, quantity, relation to stool, pain, prolapse, discharge, incontinence.

Bleeding pattern: 

  • Bright red on paper → likely distal (haemorrhoids/fissure)
  • Mixed with stool → more proximal source

Examination: 

  • Inspection
  • Digital rectal examination (DRE)
  • Proctoscopy if available

Consider further investigation or referral if: 

  • Red flags
  • Atypical presentation
  • Persistent bleeding despite appropriate treatment

Common Causes

  • Haemorrhoids
  • Anal fissure
  • Proctitis
  • Rectal prolapse
  • Diverticular bleeding (rare in young fit population)

2. Haemorrhoids

Classification

  • Grade I: Internal, no prolapse
  • Grade II: Prolapse on straining, spontaneously reduce
  • Grade III: Prolapse requiring manual reduction
  • Grade IV: Prolapsed, irreducible; may thrombose

Assessment Notes

Pain suggests thrombosed Grade IV rather than internal haemorrhoids.

Management

Conservative (first line)

  • High-fibre diet, hydration
  • Avoid straining; optimise toileting habits
  • Stool softeners
  • Short-term topical steroids/emollients
  • For thrombosed haemorrhoids: 
    • Topical agents
    • Instillagel
    • Ice/cold compresses
    • Expect spontaneous rupture → symptom improvement

Surgical Management (not usually in deployed setting)

  • Rubber band ligation
  • Haemorrhoid Artery Ligation Operation (HALO)
  • Transanal Haemorrhoidal Dearterialisation (THD)
  • Haemorrhoidectomy

Evacuate if persistent symptoms or complex/prolapsing disease with functional impact.

3. Anal Fissure

Assessment

  • Sharp, severe pain during/after defaecation
  • Sentinel skin tag
  • Visible/palpable posterior midline fissure (6 o’clock; 12 o’clock in females also possible)

Management

Conservative

  • Stool softeners
  • Warm sitz baths
  • Short-term topical anaesthetic (e.g., Instillagel)

Medical Therapy

  • Topical GTN 0.2–0.4% for 6–8 weeks
    • Headaches common
  • Topical diltiazem 2%
    • Similar efficacy, fewer side effects
  • Botulinum toxin injection
    • For refractory cases (Role 3 / specialist)

Surgical (Role 3 / specialist)

  • Lateral internal sphincterotomy (LIS)
    • High cure rate
    • Small risk of minor continence disturbance

4. Perianal Abscess

Assessment

  • Clinical diagnosis: localised pain, tenderness, swelling, erythema
  • May have fever
  • Consider deeper or atypical disease if:
    • Recurrent
    • Immunocompromised
    • Suspected supralevator abscess

Management

  • Urgent Incision & Drainage (I&D) is the primary treatment.
  • Antibiotics only if:
    • Cellulitis
    • Diabetes
    • Immunocompromised
    • Systemic sepsis
  • 40% risk of fistula formation → review at 6–8 weeks.

Evacuation Criteria

  • Complicated or deep abscess
  • Need for imaging (MRI)
  • Failed local Incision & Drainage
  • Immunocompromised patient

5. Anal Fistulae

Assessment

Determine whether simple or complex:

Complex fistula red flags:

  • High trans-sphincteric tracts
  • Anterior fistula in women
  • Multiple tracts / horseshoe configuration
  • Recurrent fistula
  • Underlying Crohn’s disease

Management

Simple Fistula

  • Fistulotomy (high cure rate; low continence risk if appropriately selected)

Complex Fistula

  • Control sepsis
  • Seton placement (sphincter-sparing)
  • Avoid any cutting procedure in Crohn’s disease
    • Seton + medical therapy (e.g., anti-TNF)

Evacuation

Required for:

  • Complex anatomy
  • Recurrent disease
  • Suspected IBD
  • Requirement for MRI pelvis

6. Rectal Prolapse

Assessment

  • Distinguish mucosal vs full-thickness prolapse
  • Assess degree, associated symptoms, continence issues

Management in Deployed Setting

  • Manual reduction (cold compress can assist)
  • Stool softeners
  • If persistent, painful, irreducible or full-thickness → consider evacuation

 

Advanced Assessment & Management

Evacuate to Role 3 if:

  • Any red flag for significant lower GI pathology
  • Complex fistula or perianal sepsis
  • Full-thickness rectal prolapse not reducible
  • Persistent, recurrent, or atypical PR bleeding
  • Need for advanced imaging (MRI, CT)
  • Suspected inflammatory bowel disease or malignancy

Paediatric Considerations

Rectal bleeding is still observed in the paediatric population. The commonest cause is haemorrhoidal from constipation. Other differentials include inflammatory bowel disease as well as non-accidental injury. 

Last reviewed: 25/08/2026

Next review date: 25/08/2027