Haemorrhoids



Anal continence requires the apposition of three mucosal pads
composed of subepithelial vascular cushions

These ANAL CANAL VASCULAR CUSHIONS are positioned
left lateral,
right anterolateral
right posterolateral

These form haemorrhoids when the pads become enlarged and congested

Haemorrhoids may cause:
- anal pain
- pruritus ani
- bright red rectal bleeding

Haemorrhoids are very common
and can occur at any age.

Aetiology



The causes of haemorrhoids is not well understood
but the following factors are important:


Constipation and prolonged straining at stool


the typical Western diet is low in fibre and haemorrhoids are more common
haemorrhoids are uncommon in developing countries

increased anal sphincter tone:


several effective treatments aim to reduce anal tone, including anal stretch procedures and nitroglycerine ointment

obstruction of venous flow may play a role:


- during pregnancy
- in patients with portal hypertension

Classification of haemorrhoids



Haemorrhoids may be either:


Internal:
with an origin above the dentate line
are generally painless

External:
with an origin below the dentate line
are generally painfull

Haemorrhoids may be of four grades:


grade I:
do not prolapse out of the anal canal

grade II:
prolapse on defecation but reduce spontaneously

grade III:
require manual reduction

grade IV:
cannot be reduced

 

 Grade I:

do not prolapse

out of the anal canal

 

Grade II:

prolapse on defecation

but reduce spontaneously

 

Grade III:

require manual reduction

 

Grade IV:

cannot be reduced

 

Internal:

with an origin above the dentate line

are generally painless

 

 

 

 

 

External:

with an origin below the dentate line

are generally painfull

 

 

 

 

 

Epidemiology



Haemorrhoids are very common.
They affect nearly half of the population at some stage in their lives.

Haemorrhoids seem to affect men more often than women
and for longer periods.

Women tend to be susceptible at particular times,
e.g. pregnancy and the puerperium.

Clinical features



Haemorrhoids often only produce intermittent symptoms.
Symptomatic episodes are often precipitated by constipation.
These episodes usually last from a few days to a few weeks.
Often they are completely asymptomatic between episodes.

Clinical features of piles include:



Bleeding after defaecation:
may just stain the toilet paper or streak the faeces,
if copious it may splash around the lavatory pan

Faecal soiling

Mucus discharge

Pruritus ani

Occasionally pain:
Thrombosis may cause acute severe anal pain occasionally necessitating hospital admission

grades 2-4 may be felt as a rectal mass