Gastrointestinal t ract d isorders
There are a number of conditions seen in special care dentistry that come within the remit of predominantly gastrointestinal disorders.
Congenital d isorders
Peutz - Jeghers syndrome is characterised by duodenal polyps which may result in part of the bowel telescoping in on itself, resulting in gangrene of the affected section of bowel if not treated. Occasionally, these polyps undergo malignant transformation. There are associated pigmented macules/polyps around the mouth.
Gardner ’ s syndrome – an inherited condition in which there are multiple osteomas, epidermoid cysts and multiple polyps in the colon, which usually undergo malignant change in about the fourth decade of life. Multiple supernumerary teeth are associated with this condition. A dental screening fi lm that detects osteomas/supernumeraries may be the fi rst clue to the disease in someone with chronic diarrhoea or ulcerative colitis.
Acquired g astrointestinal d isorders
Coeliac disease (gluten sensitivity) has a familial tendency and is seen in geographical clusters such as the west of Ireland. It is a condition that has a higher prevalence in people with Down syndrome. Coeliac disease arises as a consequence of intolerance to gluten (contained in many cereals) with a reaction between T lymphocytes in the gut wall and gluten. Eventually the villi in the wall of the intestine fl atten off and malabsorption follows. A gluten - free diet allows healing, which takes up to three months, with the duo- denal portion of the gut the last to heal. Dentally, chronological enamel hypoplasia is seen.
Ulcerative colitis involves the large bowel only, with changes confi ned to the mucosal lining of the bowel. Patients complain of diarrhoea and weight loss; anaemia is common as a consequence of rectal bleeding. Management is with systemic corticosteroids and oral 5 - aminosalicylic acid (5 - ASA) drugs. Surgery may be indicated if malignancy super- venes. Orally, there may be ulcers recorded in up to 20% of patients with the disease.
Crohn ’ s disease is a granulomatous disease that occurs in both the small and large bowel, but in discrete areas. Gradual thickening and sclerosis of the bowel wall results in malabsorption, but there may also be perforation and intestinal obstruction. The disease follows a course of remission and relapse. Patients complain of weight loss, diar- rhoea, pain and have signs of anaemia. Management is by dietary means. Corticosteroids and even immunosuppression with, for example, ciclosporin or azathioprine may be necessary for periods of time.
Orally, there may be a cobblestone appearance of the buccal mucosa (seen in orofacial granulomatosis as well) and aphthous ulcers. The latter may be the fi rst indication of the presence of Crohn ’ s disease. These can be painful and can make dental treatment diffi cult because of the discomfort. Care is needed in the placement of the aspirator tip and other manipulation of the oral tissues. Depending on how long - standing the disease is, there may be enamel hypoplasia.
Long - term immunosuppression with steroids can lead to candida and other infections and ciclosporin can lead to gingival hypertrophy.
Gastro - oesophageal disease (GORD/GERD) is a condition in which gastric contents are regurgitated back up into the oesophagus, possibly also with pepsin or bile. In some instances the stomach contents may reach the mouth. If the condition is chronic, there is
ulceration of the oesophagus because it is not designed to withstand the low pH of gastric acid. In some patients, there may be aspiration of gastric contents exacerbating a chronic lung condition like asthma. The two conditions may in fact be linked and which comes fi rst is sometimes unclear.
GORD is more common in situations where intra - abdominal pressure is raised. This can be from obesity, late pregnancy, lying supine, large meals with alcohol, hiatus hernia, diabetes and renal disease, and is also related to lifestyle factors, e.g. tobacco, some foods and drugs. It is a common condition in patients where muscle tone is altered, for example in cerebral palsy.
Untreated, patients may progress from oesophageal ulceration to stricture as a conse- quence of repeated ulceration, and fi nally to squamous metaplasia (early cancer change in the squamous lining cells of the oesophagus). Barrett ’ s oesophagus is the term applied to the latter. Where there is bleeding from ulcerated areas, iron defi ciency anaemia will be seen. If the refl ux is severe enough to reach the oral cavity, dental erosion is evident on the palatal surfaces of upper teeth and on the occlusal, and sometimes buccal, surfaces of lower teeth.
Management consists of accurate diagnosis, which may involve intra - oesophageal pH monitoring and then treatment consisting of lifestyle changes, management with antac- ids, layering agents (e.g. Gaviscon), H 2 receptor agonists (Cimetidine/Ranitidine), pro- ton - pump inhibitors (Omeprazole) to reduce acid production and drugs to increase lower oesophageal sphincter tone (Cisapride) and thus facilitate better stomach emptying.
Strictures (constriction of the oesophagus from repeated scarring from acid attacks) can be freed by dilatation, and surgery is indicated for hiatus hernias.
Liver d isease
The liver performs the following functions in the body:
■ regulation of metabolites (carbohydrates, proteins and fats)
■ production of bile, including the conversion of bilirubin from the breakdown of hae- moglobin so that it can be excreted in bile salts into the duodenum
■ detoxifi cation of absorbed toxic materials including drugs, many of which pass through the liver
■ synthesis of clotting factors under the infl uence of vitamin K.
Jaundice
This occurs as a result of accumulation of bilirubin in the circulating blood. It may be obstructive or haemolytic.
■ Obstructive jaundice : bile cannot fl ow from the liver either because of a blockage in the bile ducts or disease of the liver itself. Bile is necessary for fat digestion and so fat appears in the stools. Fat soluble vitamin K (necessary for the production of clotting factors) absorption is also affected so eventually clotting will be affected.
■ Haemolytic jaundice : premature breakdown of haemoglobin produces excess circu- lating bilirubin that the liver cannot handle. One of the inborn errors of metabolism, glucose - 6 - dehydrogenase defi ciency, classically has haemolytic anaemia as a symptom and learning disability can also be a feature. Certain drugs induce anaemia in these patients. Prilocaine (Citanest ® ) LA should be avoided in patients with this condition.
Acute and chronic liver disease produce elevated serum bilirubin levels.
Acute h epatitis
Acute hepatitis occurs as a result of:
■ increasingly, alcoholism
■ infection – viral hepatitis is the most common liver disease worldwide ■ drugs, e.g. acute paracetamol poisoning.
These conditions may become chronic and if severe may be an indication for transplantation.
Hepatitis A ( i nfectious h epatitis)
This is commonly spread as a result of poor hygiene, e.g. inadequate handwashing after toileting, contaminated water and food. Patients experience fever, nausea, vomiting, anorexia and appear jaundiced. Patients have lifetime immunity after recovering from infection. People travelling to areas where hepatitis is endemic are usually advised to have immunoglobulin A immediately prior to travel.
Hepatitis B ( s erum h epatitis)
Hepatitis B is transmitted primarily by intimate contact with body fl uids. The incubation period is two to six months, which is much longer than with hepatitis A. Intravenous drug abusers, immigrants from developing countries, Down syndrome males in residen- tial care and other institutionalised populations such as prisoners, and those in receipt of blood products, e.g. patients with haemophilia, have a higher risk of contracting hepa- titis B. Some patients progress to chronic liver disease and hepatic cancer and 2% become carriers.
All staff working with potentially infected patients should have an antibody titre in excess of 100mIU/ml to hepatitis B.
Hepatitis C ( n on - A , n on - B ) and h epatitis D
These are mostly contracted from blood transfusion products. In addition to the symp- toms described above, patients complain of pain in the area of the liver.
Vaccination for hepatitis B also confers protection against hepatitis D.
Chronic l iver d isease ( c irrhosis)
In addition to the signs and symptoms of jaundice, patients with chronic liver disease have a tendency to bleed. This arises because the portal vein becomes occluded and hypertension follows. In addition, anastomoses (connections) between the portal and other systemic veins develop varices (dilated veins), usually at the lower end of the oesophagus, which if ruptured by the increased blood pressure, result in dramatic bleeds.
A lowered concentration of plasma proteins and retention of sodium and thus water, together with portal hypertension, result in large accumulations of fl uid in the perito- neum (ascites). Patients may have grossly distended abdomens.
Patients who present with liver failure need careful consideration prior to dental treat- ment. They may be jaundiced, have impaired clotting functions and an inability to detoxify many routine drugs, e.g. LA, antibiotics, analgesics, sedatives and tranquillisers.
Adequate sterilisation protocols must be observed for all patients, irrespective of their medical history. All potentially contaminated instruments should be treated as follows.
(1) All instruments should be removed from the dental surgery to a designated area for processing. Ideally they should be placed directly into a washer disinfector. This should then be followed by sterilisation in a vacuum autoclave according to the manufacturers ’ specifi cations.
(2) If this is not possible, the following process should be used. While wearing heavy - duty gloves, wash fi rst under running water, place in an ultrasonic bath with appro- priate solution for 10 minutes, rinse, dry and inspect for residual debris. This should be removed by hand.
(3) Where sterilisation of instruments is not possible, disposables must be used.
(4) Chemical sterilisation is no longer an accepted practice.
(5) All handpieces and triple air - syringes should be fl ushed through with water for two minutes at the beginning of the day and for 20 seconds between patients to reduce the chance of microbial contamination.
(6) Where possible, sterile bottled water systems should be used for dental units and these should be drained daily and purged to clear all air/water lines.
The following events may occur post - transplantation:
■ graft rejection, but this is usually managed with drugs ■ bleeding from oesophageal varices as well as the liver itself
■ opportunistic infections – immuno - compromised patient; hepatitis B, C, D; hairy leukoplakia; and Kaposi ’ s sarcoma
■ anxiety and depression following on from immediate post - transplant sense of well - being.
Other b lood - b orne v iruses ( HIV )
HIV infects T lymphocytes to produce severe disease and eventually death. Patients develop a number of infections as a consequence of immunosuppression, particularly
pneumonias, tuberculosis, encephalitis, other neurological problems and tumours (par- ticularly the rare Kaposi ’ s sarcoma ). HIV infection ultimately progresses to a collection of signs and symptoms termed the acquired human immunodefi ciency syndrome ( AIDS ).
The virus is transmitted in body fl uids and infection has been most prevalent in those groups in the population who are at risk by virtue of:
■ lifestyle (intravenous drug abusers, homosexuals)
■ accidental exposure (patients with haemophilia, transfusion recipients in countries where blood products are not screened, possibly in transplanted donor organs, babies breast - fed by infected mothers, needlestick injuries).
Patients may present with general signs and symptoms:
■ chronic (long - standing) viral infections, e.g. herpes simplex and zoster, cytomegalovirus
■ bacterial, e.g. pneumonias, drug - resistant tuberculosis ■ fungal, e.g. candida
■ neurological defects from infections, e.g. encephalitis, peripheral neuropathy ■ tumours, e.g. Kaposi ’ s sarcoma, non - Hodgkin ’ s lymphoma.
Oral e ffects
■ Candida infection occurs early on in the disease; its progression to involve the oesophagus may result in diffi culty in swallowing.
■ Ulcerative gingivitis and periodontitis.
■ Hairy leukoplakia, seen in patients who are immunosuppressed and not just patients infected with HIV. This is due to infection with Epstein - Barr virus and affects the lateral border of the tongue after secretion of the virus from adjacent salivary glands.
■ Kaposi ’ s sarcoma exists together with herpes virus infection and as well as predomi- nantly affecting the skin, this raised, purple - coloured lesion is seen commonly intra - orally in patients with HIV (although occasionally seen in renal transplant patients as a consequence of immunosuppression).
Treatment is managed by a multiprofessional team and consists of management of infections and neoplasia, antiretroviral therapy, and appropriate counselling and support.
Dental m anagement
■ Respecting patient confi dentiality at all times is paramount and all healthcare workers must be mindful of this while at the same time conscious of their duty to protect other staff and patients.
■ Since most patients will be unaware of their disease state, all dental patients should be managed with adherence to the highest standards of infection control. Staff should have appropriate PPE, including facemasks, preferably incorporating transparent face
shields as protection from aerosol contamination. Cuts and wounds should be covered before effective handwashing and gloving. It is desirable that all staff should be vac- cinated for hepatitis B, although it is acknowledged that not everyone will seroconvert and have satisfactory antibody titres. Such staff should be offered appropriate coun- selling and be made aware of the policy to be followed should they obtain a percu- taneous injury during their work practices.
■ Needles should never be resheathed directly by hand and mechanisms must be in place to manage used needles, both for resheathing and disposal into a sharps recep- tacle. Disposables should be sealed in strong bags that cannot easily be punctured, according to the local waste disposal policy.
■ Specimens from patients should be double - sealed in strong plastic bags and the receiving laboratory notifi ed. Similarly, impressions must be disinfected in an appro- priate sodium hypochlorite solution and sealed before transfer to the laboratory, which should be notifi ed accordingly.
■ Instruments that can be sterilised should be processed appropriately following best practice recommendations within the dental surgery or sent to a Central Sterile Supply Department. Instruments that cannot be heat sterilised must be replaced with disposables prior to starting treatment. Surfaces that potentially may be contaminated should be covered with material that can be removed and disposed of between patients. Surfaces should be swabbed with an appropriate solution as per local infec- tion control policy.
Spleen
This organ is responsible for the production of some antibodies (IgM) and for the removal of worn - out red blood cells and other waste products. Although theoretically the spleen is not an essential organ, dental patients who have had their spleen removed are usually covered by prophylactic antibiotics, especially if there is other, underlying disease.
Children may be more at risk than adults.
Renal d isease
Patients with renal disease are more likely to be seen in primary dental care, with better survival both for those undergoing dialysis and for patients who have renal transplants.
The kidneys are responsible for maintaining homoeostasis – the nephrons in the kidneys fi lter over 7 litres of blood an hour, and if all this went unfi ltered the body would lose all its water and salt content in half a day. Solutes such as sodium, potassium, glucose, amino acids, by - products of metabolic processes and some drugs are fi ltered out.
Depending on the body ’ s needs, some are retained by reabsorption into the blood and the remainder are excreted in the urine.
Patients may have either acute or chronic renal disease. Acute renal failure must be treated immediately, otherwise there is irreversible damage to the kidney ’ s fi ltration
system and cardiac changes occur. Treatment is by dialysis; usually haemodialysis three times a week for 4 – 5 hours each time.
Chronic renal disease occurs with a gradual reduction in the number of functioning nephrons and evidence of this may only become apparent when the number is reduced by 75%. Because the kidney is concerned with blood pressure control, as well as red cell production and calcium balance via its role in vitamin D absorption, the effects are noted elsewhere in the body. End - stage renal failure usually follows and is treated by dialysis; this may be by haemodialysis or peritoneal dialysis, depending on a number of factors.
Peritoneal dialysis involves an exchange of fl uids through a catheter in the peritoneum so that toxins are removed over a few hours. This avoids travel to a centre for haemodi- alysis and is cheaper. If there are recurrent infections at the site of the catheter, and especially peritonitis, the patient needs to be placed on haemodialysis. Continuous ambu- latory peritoneal dialysis (CAPD) enables patients to have a reasonably normal lifestyle with dialysis going on via the peritoneum. Home - based peritoneal dialysis is used espe- cially for younger patients to prevent interference with schooling, and can be undertaken overnight.
The ideal is a renal transplant but patients are reliant on a suitable donor and in some areas there may be an upper age limit.
The signs and symptoms seen in the oral soft tissues are:
■ dry mouth – decreased salivary fl ow rate ■ metallic taste after dialysis – due to uraemia ■ enlarged tongue – due to uraemia
■ reduced response to infection (bacterial, viral or fungal)
■ no correlation between levels of plaque and calculus with the degree of gingivitis.
Increased calculus deposits are as a result of raised pH of saliva.
Bony intra - oral signs include:
■ loss of lamina dura
■ changes in radiodensity on x - rays ■ radiolucent lesions in the jaws ■ calcifi cation in soft tissues ■ malocclusions.
The teeth may show:
■ intrinsic staining (due to the disease or antibiotics or both) ■ enamel hypoplasia
■ reduced caries prevalence (raised salivary pH from urea breakdown products in saliva)
■ delayed eruption.
Dental c onsiderations in p atients on r enal d ialysis
■ These patients will be on heparin for dialysis to prevent any blockage of the arterio - venous shunt in their arm. This will complicate bleeding as the half - life of heparin is about 4 – 6 hours. Any surgical procedures should therefore be deferred until the day after dialysis, when toxins in the blood are also reduced.
■ Physicians usually prefer patients with shunts to receive antibiotic prophylaxis although there is no evidence to justify its use in these circumstances. The kidney ’ s capacity to handle some antibiotics is altered and should be avoided long term. For example, potassium - containing penicillins, tetracyclines and cephalosporins are all toxic to the kidney; erythromycin is a safer alternative.
■ Normal infection control procedures should be instituted. Because of dialysis, the prevalence of blood - borne viruses, hepatitis B, C and D, and HIV are potentially greater. Dialysis also predisposes patients to bony changes (renal osteodystrophy) and secondary hyperparathyroidism (see parathyroid glands), which is seen as cystic - like lesions in the jaw bones on routine dental orthopantomograms.
Patients with renal disease have:
■ anaemia, unless well controlled. This is secondary to the uraemia, a lack of erythro- poietin production by the kidney, blood loss during dialysis and the shortened life span of the red blood cells. It is treated by iron supplements. This is a consideration for patients contemplating GA
■ biochemical abnormalities ■ hepatitis risk from dialysis ■ renal bone disease
■ raised blood pressure (hypertension)
■ need for antibiotics to protect the arterio - venous anastomoses.
Renal t ransplant p atients
Patients with end - stage renal failure may be successful in obtaining a cadaveric donor organ or allograft from a matched donor, usually a close relative. Once normal renal function is restored after transplantation, the patient can be treated as if the kidney is normal. However, they will be taking a number of drugs, namely:
■ immunosuppressants to prevent rejection of the graft ■ antibiotics for prophylaxis against UTI
■ antihypertensives for blood pressure control
■ calcium channel blockers for blood pressure control.
These can have side effects such as gingival overgrowth. The patient ’ s care should take into account management of these drug - related effects as well as underlying diseases,