Proctalgia fugax

Specialty: Gastrointestinal.

• Transient spasmodic anal pain
• transient functional anorectal neuralgia
• acute rectal spasm

Why it occurs

• Idiopathic spasm of the internal anal sphincter muscle or levator ani (functional anorectal pain disorder according to Rome IV criteria)
• Pelvic floor hypertonia exacerbated by emotional factors, generalized anxiety or acute stress
• Chronic unhealed anal fissure that generates a reflex spasm of the sphincter muscles
• Pudendal nerve neuropathy due to local compression (prolonged cycling) or previous perineal trauma.

Initial workup

Meticulous anorectal physical examination in consultation (dynamic anal inspection, digital rectal examination and anoscopy to rule out fissures, thrombosed hemorrhoids, fistulous tracts or masses) | High-resolution endoanal ultrasound or MRI of the pelvis if pain becomes chronic and atypical | Anorectal manometry to document the presence of severe basal hypertonia of the internal anal sphincter.

Standard management

• Nitroglycerin in rectal ointment — anal application at 0.2% - 0.4% every 12 hours or during acute spasm, induces relaxation of the internal anal sphincter through the action of nitric oxide, controlling headache as a common side effect
• Topical calcium channel blockers — 2% diltiazem gel or nifedipine ointment applied locally to reduce sphincter tone
• Local anesthetics — 2-5% lidocaine ointment applied intra-anally to provide immediate symptomatic relief
• Salbutamol inhalation (100-200 mcg inhaled at the time of pain to relax the smooth muscles of the sphincter by beta-2 adrenergic stimulation in refractory recurrent cases).