Sjogren's Syndrome and the Gastro-Intestinal Tract
by Doctor Richard Mount ford MD, FRCP, FRCR.
Consultant Physician, Department of Gastroenterology, Bristol Royal Infirmary
In a way, it is surprising that I do not see more digestive problems in patients with Sjögren's syndrome than I do, in my work as a gastroenterologist. After all, saliva is the first fluid made by the body to come in contact with our food. It must, therefore, be important in the digestive process. I do not see large numbers of sufferers from Sjogren's syndrome complaining of problems with eating or digestion. Of course, this may simply mean that they put up with their symptoms, or that their family doctors feel that hospital specialists will not be able to help. Nonetheless, there are many areas where the gastroenterologist may have a part to play, if it is only in establishing the correct diagnosis. I will try to outline some of these.
SWALLOWING DIFFICULTIES
I can only try to imagine how difficult it would be to try to chew and swallow without adequate amounts of saliva. Much of the enjoyment of eating must be lost without proper lubrication. However, severe malnourishment or vitamin deficiencies are not problems which have commonly come my way. On occasion, difficulty in swallowing goes beyond that to be expected with lack of saliva. Food may stick in the gullet if there is a blockage, or if there is a weakness of the muscle contractions involved in swallowing.A sensation of food sticking, sometimes with it being returned or regurgitated to the mouth, is always frightening. Often patients are worried that they have a growth in the gullet causing such symptoms. Happily, in Sjögren's syndrome there is often another, less serious explanation for the symptoms. One of the less common complications of the condition is a postcricoid web. This is a thin membrane which forms across the top of the gullet, behind the voice-box.It starts at the front of the gullet and grows backwards. It is not known why this happens, but it is associated often with longstanding iron deficiency anaemia. Treatment is by stretching the gullet, which will happen automatically if a flexible telescope is passed into the stomach (endoscopy).As well as lubrication, saliva has an important role in protecting the gullet. The stomach produces hydrochloric acid and strong enzymes to digest food. The resulting juice is highly corrosive, rather like battery acid. The stomach is designed to protect itself, but the gullet is delicate and easily damaged and inflamed if its surface is bathed with acid. Hence, there is normally a valve at the lower end of the gullet, which permits food and drink to pass down into the stomach, but which prevents gastric acid from rising back upwards. The way that this works is that there is a ring of muscle, called the lower oesophageal sphincter, which is normally contracted, with the effect of closing off the gullet and hence preventing reflux of acid back up from the stomach. When we swallow, the muscles of the gullet contract in sequence from above downwards to produce a wave effect pushing the food or drink downwards. When the food or drink arrives in the lower gullet, the muscle in the lower oesophageal sphincter relaxes, allowing it to pass through into the stomach. The muscle then contracts again, so that the valve snaps shut, preventing reflux of stomach contents. This clever arrangement cannot work one hundred percent all of the time, so in all of us some acid leaks back into the gullet intermittently. Saliva has an important role in washing out the gullet, removing these traces of acid and as it is alkaline, it also has a neutralising effect.As you would predict from the above, sufferers from Sjogren's syndrome are vulnerable to acid refiux, which causes the symptoms of heartburn. Severe acid inflammation of the lower gullet may produce a sensation of blockage. Furthermore, continuing inflammation may lead to scarring and narrowing of the gullet (oesophageal stricture). Happily, this can usually be easily treated nowadays with stretching of the gullet by endoscopy, plus taking tablets to reduce acid production by the stomach.Difficulty in swallowing may also result from problems with the muscles in the gullet. Weakness of these muscles is relatively common in Sjogren's syndrome and this can be difficult to treat, though there are tablets which can enhance the strength of their contractions. Another problem can be that although the individual muscles contract strongly, they do so in an uncoordinated way. In order to produce a good swallow, the muscles must contract in sequence from above downwards, to produce the wave or ripple effect described above. If they fire off in unsynchronised fashion, out of sequence with one another, food or drink will not propelled downwards in the proper way. Again, this can be difficult to treat, there are tablets which may improve the situation.A particular type of muscular problem has been reported in some children with Sjogren's syndrome. This is call achalasia of the cardia (or simp achalasia). This involves the lower oesophageal sphincter. As was mentioned above, this is a specialised ring of muscle in the lower gullet, which is normally contracted, but which needs to relax when food or drink is swallowed, to allow passage out of the gullet and into the stomach. In achalasia, relaxation of the muscle fails to occur. This means that the valvular mechanism remains shut, and food and drink is held up in the gullet, unable to enter the stomach.Achalasia does not respond well to tablet treatment. In the past, the standard treatment was an operation, involving an incision in the abdomen. The surgeon would make an incision through the muscle in the lower gullet, rendering it permanently incapable of contraction. Thus, in effect, instead of the valve being stuck shut, it is converted to being constantly open.This sort of surgery is still necessary on occasion. However, many patients with achalasia can be treated using the endoscope. Using this instrument, it is possible to place a balloon in the lower oesphagus. When this is inflated, the muscle is stretched. This can produce the same sort of permanent reduction of muscle contraction as the surgeon 's incision. More recently it has been found that the muscle can be made to relax by being injected, again using the endoscope. The material which is injected is botulinum toxin. Botulinum is a naturally occurring bacterium, which produces a poison or toxin, which produces profound muscle relaxation. The bacterium has very rarely contaminated tinned food, when the canning process was faulty. It has been found that it is safe to inject tiny amounts of this toxin into muscles which are contracting abnormally. The injection results in relaxation of the muscle. In the lower oesphageal sphincter, the relaxation tends to wear off after a year or so, but the injection can be repeated if necessary.
INDIGESTION
Dyspepsia is relatively common in patients with Sjogren's syndrome. There are probably many reasons for this. Heartburn has been discussed above. This can usually be treated fairly easily with medication to neutralise gastric acid, or to reduce its production.Another problem which sufferers from Sjogren's syndrome seem to be at increased risk of developing, is inflammation of the stomach, or gastritis. This is inflammation of the stomach lining. It can only be definitely diagnosed by doing an endoscopy and taking biopsies - small specimens of the lining of the stomach - for examination under the microscope. Many sufferers from gastritis describe abdominal discomfort after eating, sometimes with bloating and wind.The cause of gastritis in Sjogren's syndrome is not clearcut. In many patients, the lining of the stomach becomes thinner than normal and there is a reduction in the number of acid-producing glands. This is known as atrophic gastritis. In this situation the stomach produces less acid than normal. It has been suggested that the cause of atrophic gastritis is, in some cases, the result of an auto-immune process. The immune system exists in the body to protect it from damage from a number of external factors which might be injurious particularly infective microbes. It does this in a variety of ways, including the production of antibodies, which are proteins which appear in the blood and can attack and destroy invading microbes. In some unfortunate people, this mechanism goes wrong, and abnormal antibodies are produced which attack and destroy normal body tissues. In Sjogren's syndrome, the salivary and tear glands are attacked. Sometimes this process goes further and other so-called "auto-antibodies" are produced which attack other cells in the body. Atrophic gastritis may be the result when auto-antibodies are produced which attack the cells lining the stomach. As well as acid, these cells produce a chemical which is essential in permitting the body to absorb vitamin B12 from the food. Without this chemical, the body runs short of vitamin B12, which the bone marrow needs to make red bloodThis leads to the condition of pernicious anaemia. As its name suggests, this was once a serious indeed, often fatal type of anaemia. Fortunately it can now be very simply treated by giving the vitamin, in injection form, once every three months.
In recent years, gastroenterologists have become very excited and interested in a newly discovered bacterium which causes gastritis. This microbe is called Helicobacter pylori. It lives in the coat of slime which covers the stomach. Once established within the slime, the bacterium is protected from attack by stomach acid and indeed it is difficult for antibiotics to work against a microbe living in this particular environment. Hence the bacterium is capable of living in the stomach for long periods of time. It appears that the infection is usually picked up in childhood, when standards of hygiene are not as good as those which are normal during adult life. Once the infection has taken place, the bacterium may live quite happily in the stomach for decades, indeed throughout life, unless it is destroyed with specific treatment, which includes at least two antibiotics, taken together.
Infection with Helicobacter pylori is very common, particularly in the developing world. In parts of Africa and Asia virtually the whole population acquires infection with the bacterium in early life. The presence of the bacterium causes local inflammation, i.e. gastritis. This may not do too much harm, and it appears that some strains of the bacterium are more aggressive or virulent than others.In this country, the risk of being infected varies very much with age. Older people are much more likely to have been infected than younger people. They almost certainly were exposed to the bacterium in childhood, years ago, when standards of hygiene were less good than they are today. As time goes by, it appears that fewer children are contracting the infection, so the bacterium should become less and less of a problem.
Sometimes infection with Helicobacter pylori causes more severe problems than simple gastritis. Some strains of the bacterium, when they colonise the stomachs of susceptible people, cause the acid secreting cells to work overtime. This leads to the production of excessive amounts of acid, which in turn can result in duodenal or gastric ulcers. Some ulcers may heal up temporarily, if tablets are taken which reduce the production of acid but once the treatment stops, the ulcers tend to come back.
However, if Helicobacter pylori is eradicated, by taking combinations of antibiotics, excess acid is no longer made. In these circumstances the ulcers heal up and do not return.Research has been carried out to see if infection with Helicobacter pylori accounts for the gastritis seen in Sjogren's syndrome. Certainly, many patients with the syndrome have acquired the infection, but the proportion seems to be much the same as that seen in the general population. What is very interesting is that in Sjogren's syndrome, the infection seems to be particularly difficult to treat. Combinations of antibiotics which are successful in eradicating the infection in a high proportion of normal people, are very much less effective in sufferers of Sjogren's syndrome. This is obviously important, but the reason for this phenomenon has not yet been discovered.
DIARRHOEA
There are at least two diseases which are associated with Sjogren's syndrome, which may produce diarrhoea. These are chronic pancreatitis and coeliac disease.The pancreas gland produces hormones like insulin which are released into the blood, and also enzymes like lipase which are secreted into the intestine, as part of the digestive process. If the pancreas becomes diseased, there may be a deficiency of either hormones or enzymes, or both. Lack of insulin leads to diabetes. A deficiency of enzymes like lipase leads to incomplete digestion. This means that some foods are not properly broken down and pass straight through the digestive tract. Undigested, or only partly broken-down food turns up at the other end. resulting in diarrhoea.Happily, this situation is amenable to treatment. Diabetes can be treated with injections of insulin and the deficient enzymes can be given in tablet form, usually with meals.It must be emphasised that only a tiny minority of patients with Sjogren's syndrome also have chronic pancreatitis. When it occurs the mechanism is not certain, but it may be another example of damage by auto-antibodies. Auto-antibodies are detectable in the blood of almost all patients with coeliac disease. In this condition, patients are allergic to foods containing wheat. When they eat bread, cakes or pastries the lining of the intestines becomes damaged. This again results in food going straight through the system, resulting in diarrhoea. The treatment for this condition is a strict diet, called "gluten-free".Sufferers have to eliminate all wheat products from their diet. This is burdensome, but highly effective in relieving the symptoms and in time the lining of the intestine repairs itself. Unfortunately, patients with coeliac disease have to persevere with the diet throughout their lives.
JAUNDICE
The final condition I would like to mention is a type of liver disease called primary biliary cirrhosis. This is another disease associated with Sjogren 's syndrome. Again I would emphasise that although primary biliary cirrhosis is statistically more likely to occur in patients with Sjogren's syndrome than in normal people, it is rare to find a patient unlucky enough to have both conditions. Primary biliary cirrhosis is a very misleading name. "Cirrhosis" is always linked in peoples' minds with excessivie drinking of alcohol. Primary biliary cirrhosis however has absolutely nothing to do with alcohol; it is yet another example of an autoimmune disease. In this case the auto-antibody involved is the anti-mitochondrial antibody, which is present in the blood of virtually all sufferers from primary biliary cirrhosis.
The condition usually occurs in middle aged women and it presents with rather non-specific symptoms such as fatigue and itching of the skin. As the disease proceeds, the patients may become jaundiced. It used to be thought that it invariably progressed, leading to worsening liver damage. However, it is now known that in many cases, the condition is mild with only very slow deterioration. Furthermore, the progress of the damage can be slowed by taking medication in the form of tablets or capsules containing a naturally-occurring bile salt called ursodeoxycholic acid. In the unlucky minority of patients in whom the disease is aggressive, so that the liver becomes more and more damaged, transplantation with a new, donor liver is highly successful.
CONCLUSION
There are many conditions linked to Sjogren's syndrome, where the gastro-enterologist may be of some help. Often the link between Sjogren's syndrome and gastroenterological conditions is via abnormal auto-antibodies. Research has permitted many advances to be made in the diagnosis and treatment of these disorders.
Sjogren's Syndrome :
An Advisory Guide for Patient's and Doctors : £2.50
This booklet is produced by BSSA and is an invaluable source of information on Sjogren's syndrome both to newly diagnosed patients and also G.P.s, junior hospital staff, dental surgeons and nurses who will find the contents helpful in understanding the problems of paitients with the disorder.
Note:
WebHealth has additional articles about Sjogren's Syndrme at:
Systemic Features By:
Dr Ian Griffiths, Dr Elizabeth Price, Dr Clive Kelly and Dr Patrick Venables
and
The Problems of Sjogren's Syndrome By:
Dr CW Hutton, Consultant Rheumatologist, Demford Hospital, Plymouth
and
Sjogren's Syndrome and the Gastro-Intestinal Tract By
Doctor Richard Mount Ford MD, FRCP, FRCR.
Consultant Physician, Department of Gastroenterology, Bristol Royal Infirmary
and
Neurological problems in Sjogren's Syndrome by Doctor Annabel Coote and Doctor Michael Snaith, Department of Rheumatology, Royal Hallamshire Hospital, Sheffield.
and
Sjogren's Syndrome and the Respiratory System
A Brief History of Sjogren's Syndrome By
Doctor Ian D Griffiths FRCR, Consultant Rheumatologist,
Freeman Hospital, Newcastle-Upon-Tyne
