|Conditions Affecting the
A wide array of conditions may affect the anal canal, but generally
present with either pain, bleeding or feeling a lump around the anus.
The following is a summary of the most common and important of these
Haemorrhoids or piles are enlarged, bulging blood vessels in and about
the anus and lower rectum. Haemorrhoids are very common and many
people will not even know that they have them. Generally however they
cause bright red bleeding which is seen on the toilet paper and
occasionally in the toilet following opening your bowels. Patients may
also notice itching around the anus.
Sometimes patients notice a lump
around the anus which may need to be “pushed back” or may return to
the anal canal on their own following a bowel movement. These are
known as “prolaped” haemorrhoids. Some prolapsed haemorrhoids are
unable to be pushed back and these may become extremely painful,
however haemorrhoids are generally not painful. Although having piles
does not lead to any increased risk of developing cancer, the symptoms
may also be seen in patients with colorectal cancer and should be
evaluated by a doctor.
What causes haemorrhoids?
The exact cause is not known, however a number of factors are thought
to contribute. The fact that humans walk upright increases the
pressure on the rectal blood vessels which causes them to bulge out.
Other factors include: aging, chronic constipation, pregnancy, family
history, straining during bowel movements and spending long periods of
time on the toilet (i.e. reading).
What is the best treatment?
The simplest treatment is to increase the amount of fibre (e.g.
fruits, vegetables, breads and cereals) and fluids in the diet, avoid
straining or spending a long time on the toilet. This avoids
constipation and reduces the pressure in the anal canal. If the pile
is uncomfortable sitting in a bath of warm water for 10 minutes or so
may give some relief. If haemorrhoids are particularly troubling a
variety of procedures can be performed as an outpatient.
Rubber band ligation
For larger haemorrhoids placing a small rubber band around the base is
an effective treatment. The band cuts off the blood supply to the
pile. The pile and band fall off in a few days leaving behind a small
wound which heals in a week or so. When the bands are applied some
patients may feel some discomfort at the time and for a few days
after. Bands may need to be re-applied on several occasions for
symptoms to resolve completely.
Injection of the haemorrhoid with phenol works in a similar way to
rubber band ligation with the injection causing the pile to shrivel.
Again this may be mildly uncomfortable and may need to be repeated.
Removing the pile surgically is reserved for severe haemorrhoids which
are too big to be treated with the above techniques. Although after
the procedure patients may have marked pain and discomfort the
operation is safe, highly effective at curing piles and can usually be
performed as a day case. Laxatives and pain killers are routinely
prescribed, however patients should expect to take some time from
usual activities following their operation.
Recently a technique using a special staple gun to remove internal
haemorrhoids has been developed. It is successful at treating internal
piles but does not remove any portion outside the anal canal if
present. It is more painful than outpatient techniques but less
painful than a traditional haemorrhoidectomy.
Patients may suddenly develop a small painful lump at the edge of the
anus. This often happens after passing stool and represents an
ruptured blood vessel at the edge of the anal canal. It is not
sinister and often resolves itself, often by discharging a small
amount of blood as the clot bursts. Avoiding constipation and using
simple painkillers is often all that is required. Sitting in warm
water for about 10 minutes may also help and the pain usually subsides
in a few days. If the pain is severe or persistent the blood clot can
be evacuated using a small incision under local anaesthesia as an
outpatient to provide relief.
Patients with an abscess around the anal canal present with severe
pain often associated with fever and feeling generally unwell.
abscess forms when one of the glands which surround the anal canal
becomes blocked and infected with bacteria. Some groups of patients
such as those with Crohn’s disease are more prone to develop these
abscesses. In those with diabetes or who have a reduced immunity peri-anal
abscesses may be very dangerous and should be treated immediately. The
treatment for these abscesses is by surgery.
A small incision is made over them and
the pus evacuated. Due to the sensitivity of the area and need to be
sure all infected material has been removed they should be performed
under general anaesthetic in hospital. Often the cavity may be large
and will require regular dressing by the district or practice nurse
until it has healed properly. Although antibiotics are sometimes
tried, they work poorly in this condition since they do not penetrate
the inside of the abscess cavity. Following healing of the abscess
around half of those treated will go on to develop a fistula.
An anal fistula is a connection, or tunnel, between the inside of the
anal canal and the skin around it. It is the result of a previous
abscess which develops when the anal glands become blocked and
subsequently infected. Fistulas present about 4-6 weeks after an
abscess has been treated but may become obvious months or years later.
A fistula leads to persistent discharge of pus or fluid around the
anus leading to soiling of underwear and skin irritation. Occasionally
the fistula may appear to have healed only for a recurrent abscess to
form. Patients with Crohn’s disease are particularly prone to the
development of anal fistulas.
What is the treatment for a
Surgery is the treatment of choice to cure an anal fistula. Dealing
with most fistulas is straightforward involving simply opening the
fistula tract (laying open) and joining the internal opening to the
external opening. This wound is then allowed to heal slowly and
requires regular dressing changes by a district or practice nurse.
Some fistulas however, are more difficult to treat. Since many
fistulas pass from the anal canal through the muscles that control
bowel continence (the anal sphincters) and out to the skin, laying the
fistula open may lead to the division of a small portion of these
muscles. If the fistula passes through the sphincters near the top of
the anal canal (a high fistula) too much muscle would be divided and
there would be a risk of developing incontinence to stool. In these
complex cases there are a variety of techniques available including
the use of setons (a suture passed through the fistula), advancement
flaps and even artificial plugs or glues made from collagen. It is
important to discuss these risks with your surgeon.
An anal fissure is a small tear in the skin that lines the anus. They
present with pain on defecation and bright fresh rectal
usually o the toilet paper. The pain associated with a fissure may be
so severe that patients avoid going to the bathroom, this leads to
constipation and even more pain. Often patients will not allow their
doctor to examine their anus since the pain is unbearable, this is
almost diagnostic of a fissure. Fissures typically occur following
trauma to the lining of the anal canal, this is commonly due to
passing hard dry stool such as with constipation. They may also be
associated with inflammatory conditions such as Crohn’s disease.
Fissures are divided into acute, which are of new onset, and chronic
which have been present for over 6 weeks or are recurrent. Chronic
fissures are usually associated with a small skin tag at the anal
margin known as a sentinel pile.
How are fissures treated?
Acute fissures are likely to resolve without the need for surgery.
Simple measures to avoid constipation such as increasing the amount of
fibre in the diet, increasing liquid intake, using stool softeners are
often sufficient. If a chronic fissure develops these simple measures
should be instigated but the addition medical treatments should be
instigated. Applying a pea sized lump of 2% diltiazem cream to the
anal canal twice a day is a simple measure which causes the anal
sphincter muscle to relax and leads to fissure healing in over 50% of
Although some favour the use of GTN
ointment, which has the same effect as diltiazem, this may not be
tolerated by some people due to the development of headaches. If
creams fail, injecting Botox (botulinum toxin) directly into the
sphincter muscle can be attempted and may lead to healing in up to 75%
of patients. If these treatments fail consideration should be given to
surgery. This usually consists of an operation to cut a small portion
of the internal anal sphincter muscle (a lateral sphincterotomy). This
is a highly effective treatment for a fissure with complete healing
occurring in a few weeks. There is however, a small risk of minor
incontinence following this procedure and the benefits and risks
should be discussed with your surgeon.
Anal cancers usually arise from the skin cells (squamous cells) around
the anal opening and are known as squamous cell carcinomas. Anal
cancer is relatively uncommon accounting for 1% of all
gastrointestinal cancers with colorectal cancer being around 40 times
more common. Some patients develop pre-cancerous cells, which require
regular surveillance, these are known as carcinoma-in-situ. The
symptoms of anal cancer are similar to those of many anal canal
lesions such as itching, bleeding, pain, feeling a lump, an alteration
in bowel habit and even swollen glands in the groin. Since the anal
canal is an area easily accessible to doctors, making an early
diagnosis should be possible with rectal examination and simple biopsy
under anaesthetic. Risk factors for developing anal cancer include;
age, the presence of anal warts and infection with the human papilloma
virus (HPV), anal sex, HIV infection, smoking, impaired immunity and
previous pelvic irradiation.
How are anal cancers treated?
Following diagnosis patients undergo a series of tests such as an MRI
scan of the anal canal and a CT scan of the whole body to asses the
extent of the cancer. The mainstay of treatment is a combination of
chemotherapy and radiotherapy which is highly effective in most cases.
Surgery is seldom used as a first line treatment, unless the cancer is
very small and can be completely removed without damaging underlying
structures. Surgical intervention may be used to create a stoma whilst
chemotherapy and radiotherapy is proceeding to reduce the risk of
diarrhoea, incontinence and pain on defecation. This is usually a
temporary stoma and is reversed when the treatment is completed and
the cancer eradicated. Occasionally the cancer is not completely
destroyed by the combined treatment or recurs, in these cases
“salvage” surgery is indicated to remove the entire rectum and anal
canal leaving the patient with a permanent colostomy (abdomino-perineal
resection). Thankfully such procedures are undertaken rarely these
days and survival rates of X% are reported.