INTERNAL Hemorrhoids
– Found proximal to the dentate line
– Visceral innervation
Behavioural or Genetic Predisposition
I.e. hereditary bowel/rectal problems or
shared habits and practices (unclear mechanism)
Increased Intra-Abdominal Pressure
I.e. pregnancy, constipation, chronic straining,
lifting, cirrhosis
Hemorrhoids: Pathogenesis and clinical findings
Dilations originate from inferior
hemorrhoidal venous plexus
Vascular cushions engorge
along anal canal
Legend: Published March 30, 2019 on www.Pathophysiology Mechanism Sign/Symptom/Lab Finding Complications thecalgaryguide.com
Authors:
Aleeza Manucot
Reviewers:
Yoyo Chan
Sean Doherty
Dr. Sylvain Coderre*
* MD at time of publication
Supporting tissues of anal cushions weaken,
disintegrate, or deteriorate
Inflammatory reaction
occurs, involving vascular
wall and connective tissue
Thrombosis
Pain
↑ mucus secretions or fecal
soiling of prolapsing
hemorrhoids
Cushion epithelium erodes via
damage from compression
Painless
rectal
bleeding
Bleeding without prolapse
Prolapse with spontaneous
reduction
Prolapse requiring manual
reduction
Irreducible
1st degree
2nd degree
3rd degree
4th degree
Infarction and thrombosis
Acute severe pain
Anal cushions prolapse (downwardly slide)
into rectum or open space
Dentate line: divides
the upper two thirds
and lower third
of the anal canal
EXTERNAL Hemorrhoids
– Found distal to the dentate line
– Somatic innervation
Somatic nerve
receptors activated
Sebaceous glands
↑ secretions around
area of hemorrhoid
Itching Perianal
irritation
Swelling
Inflammation creates
prothrombotic state
Hemorrhoids