Medical Matters: It is always a pleasure to receive correspondence from readers. Much of this is via the email address at the bottom of the column, but some arrives by regular mail to me c/o The Health Supplement.
One such item to arrive recently was from a group who modestly signed themselves "a few Dublin readers - old fashioned in that we are not high tech". They had a number of questions, one of which has prompted me to devote this week's column to the subject of haemorrhoids.
Probably the butt(!) of more jokes than most other medical conditions, haemorrhoids - or piles to give them their lay term - are common. About one in four people in the western world suffer from haemorrhoids at some stage in their lives, particularly between 20-50 years of age.
Many patients suffer for long periods in silence before gingerly mentioning that they have a problem "in the back passage". This is entirely understandable: which of us wants a doctor examining our bottom and carrying out a digital rectal examination as part of the ordeal?
Such a delay in dealing with the symptoms of haemorrhoids will cause no harm except where bleeding from the back passage occurs. Although haemorrhoids are the commonest reason for passing bright red blood from the rectum, other more serious gastrointestinal illnesses can present with anal bleeding. So never ignore this symptom or presume it is caused by piles, especially if you are over 40.
What is a haemorrhoid? At the upper end of the anus where it meets the rectum, the smooth lining of the bowel bulges to form what are called the anal "cushions". Usually three in number, they are a mixture of elastic tissue and small blood vessels. These cushions lie in contact with each other, sealing off the upper anus and helping us to keep control over intestinal gas. However, they can be enlarged and congested under certain conditions. When they do, they are called haemorrhoids.
As the haemorrhoid gets larger, it slides down the anal canal and protrudes externally. Doctors refer to this as prolapse. Often the prolapsed haemorrhoid retreats internally of its own accord. However, if the pile is especially large it may require gentle assistance to return. When haemorrhoids are very large they become permanently prolapsed, causing itching, discomfort and sometimes bleeding on contact with underwear. Repeated prolapse of a pile leads to the development of a perianal skin tag - an irregular flap of skin around the anal opening.
My Dublin correspondents specifically asked if haemorrhoids could be caused by factors other than constipation. The biggest factor is having to strain in order to complete a constipated bowel motion but heavy physical exertion, such as lifting, can cause piles. People who sit for long periods, such as bus and lorry drivers, are more prone to the condition and pregnancy is another recognised cause.
Reading on the loo can give you haemorrhoids, according to research published in the Lancet. Doctors at the John Radcliffe Hospital, Oxford, compared the habits of 100 people suffering with haemorrhoids with 100 unaffected people and found that a much larger proportion of the group suffering from haemorrhoids read while on the toilet - the researchers blamed the undue pressure on your bottom while sitting for long periods.
In terms of treatment, having a regular bowel habit and avoiding constipation is the first and most important step. Creams and suppositories will help occasional flare-ups in itch, discharge and discomfort. Haemorrhoids can be made to shrink by injection with a solution of oil and alcohol. Larger haemorrhoids can be "strangled" using tiny rubber bands placed at the base of the pile using special instruments. Haemorrhoidectomy - the surgical removal of the haemorrhoid along with the nearby skin and anal lining - is the final solution. This procedure is carried out by general surgeons.
The diagnosis is fairly straightforward once a full rectal examination is carried out. As an old professor of mine used to advise: "Always put your finger in, in order not to put your foot in it!"
Dr Muiris Houston is pleased to hear from readers at mhouston@irish-times.ie but regrets he cannot answer individual queries.