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Flashcards in GI III Deck (47):
1

Longitudinal layer of the appendix

The appendix forms a wormlike (vermiform) structure as it does not elongate as rapidly as the rest of the colon.

The average length is 10 cm (range from 2-20 cm). The wall of the appendix consists of two layers of muscle, an inner circular and outer longitudinal. The longitudinal layer is a continuation of the taeniae coli.

The appendix is lined by colonic epithelium. Few submucosal lymphoid follicles are noted at birth. These follicles enlarge, peak from 12-20 years, and then decrease. This correlates with the incidence of appendicitis.

Blood supply to the appendix is mainly from the appendicular artery, a branch of the ileocolic artery. This artery courses through the mesoappendix posterior to the terminal ileum.

The base of the appendix is fairly constant and is located at the posteromedial wall of the caecum about 2.5 cm below the ileocaecal valve. This is also where the taeniae converge. The base is at a constant location, whereas the position of the tip of the appendix varies.

In 65% of patients, the tip is located in a retrocaecal position; in 30%, it is located at the brim or in the true pelvis; and, in 5%, it is extraperitoneal, situated behind the caecum, ascending colon, or distal ileum.

The location of the tip of the appendix determines early signs and symptoms.

2

Perineal body attachments

Deep transverse perinei
External anal sphincter
Levator ani
Pubovaginalis

The tendinous centre of the perineum or perineal body is a small wedge-shaped mass of fibrous tissue located at the centre of the perineum.

Other structures attached include the external anal sphincter, levator prostate which is a part of levator ani, bulbospongiosus and superficial and deep transverse perinei.

3

Gastric MALT disease

Gastric MALT tumours are associated with H. pylori infection in approximately 98% of cases, and all that is usually required in low grade disease is eradication therapy.

High grade disease is best treated with chemotherapy, and the prognosis for these tumours is excellent.

Paraproteinaemia is commonly found.

4

Malabsorption and HPylori

Malabsorption may be associated with numerous disorders but typically occurs with:

Pancreatic exocrine deficiency
Short bowel syndromes
Coeliac disease, and
Inflammatory bowel disease (IBD).
Helicobacter is associated with peptic ulceration not malabsorption.

Chronic mesenteric ischaemia is typically associated with pain soon after eating but many patients lose weight due to malabsorption.

5

Dupuytren's contracture associations

Alcoholic liver cirrhosis
Diabetes mellitus
Epilepsy IncorrectIncorrect answer selected
Peyronie's disease

Volkmann's ischaemic contracture is not associated.

Dupuytren's contracture is a progressive thickening of the palmar fascia causing a flexion contracture of the hand, mainly affecting the ring and little fingers.

It is also associated with diabetes mellitus.

6

Crohns disease associations
U AIM APE

Crohn's disease is associated with:

Arthropathy
Ankylosing spondylitis
Iritis
Malabsorption
Erythema nodosum
Pyoderma gangrenosum.
Urinary oxalate stones

7

Achalasia features

Achalasia is a functional obstruction of the lower oesphageal sphincter with dilatation of the oesphagus above caused by degeneration of the ganglion cells on the muscle of the mid and lower oesophagus.

The diagnosis is made radiologically, and manometry confirms the diagnosis by showing an elevated sphincter pressure - there is a failure of relaxation of the sphincter.

Dysphagia is an early feature, slowly progressive both for solids and liquids.

Interscapular pain may be associated with pain though not characteristic.

Carcinoma is a rare complication. Iron deficiency is characteristically associated with a post-cricoid web (Patterson Brown-Kelly or Plummer Vinson syndrome) and unrelated disorder of the oesophagus.

8

UC features

UC is associated with

Arthropathy
Ankylosis
Ascending cholangitis
Sclerosing cholangitis
Cholangiocarcinoma
Cirrhosis
Cholelithiasis.
The hepatic features are more typical of UC than Crohn's.

It is also associated with a greater risk of malignancy.

9

Bile

Normal bile is an alkaline hypotonic electrolyte solution composed of bile pigments and salts, with about 500 ml secreted per day.

A small amount of unesterified cholesterol is excreted in bile.

Ninety five percent of bile salts are absorbed from the terminal ileum.

10

Reflux oesophagitis

Reflux oesophagitis is associated with

Barrett's oesophagus
The use of agents such as steroids
Obesity
Raised intrabdominal pressure.
There is no reliable histological appearance, but it is generally a clinical diagnosis.

11

GI malignancy conditions

Barrett's oesophagus
Coeliac disease
Peutz-Jeghers syndrome
Menetrier's disease

Gastric ulceration is associated with cancer. Duodenal ulceration (untreated by surgery) may afford some protection from gastric cancer.

Barrett's oesophagus is related to oesophageal carcinoma. Reflux is probably aetiological in Barrett's oesophagus. There may be an association between chronic reflux and cancer.

Coeliac disease is associated with intestinal lymphoma.

Peutz-Jeghers syndrome, once considered to be benign, is also associated with an increased risk of bowel neoplasia.

Menetrier's disease is a hypersecretory gastropathy which has an increased risk of gastric cancer. (Meniere's disease is a condition of the middle ear).

12

differential diagnosis of a young man with bloody diarrhoea.

Infective causes plus inflammatory bowel disease should be considered in the differential diagnosis of a young man with bloody diarrhoea.
Shigellosis is a possible cause. Most cases of Shigella infection are related to foreign travel. Unrelated to foreign travel, there has been an increase in sexually transmitted Shigella infection in men who have sex with men.

Trophozoites seen in acute dysentery. Cysts for E. Histolitica are not 100% sensitive for amoebic dysentery.

Watery diarrhoea would be expected with cholera and giardiasis.

13

Gastric cancer assoications

Not with chronic gastric ulcer.

Gastric carcinoma should be considered if the symptoms of the duodenal ulcer return many years after partial gastrectomy. The risk increases above the rate in the normal population about 15 years after surgery. The overall risk is between 3% and 10%.

Helicobacter pylori infection increases the risk of gastric carcinoma by 3-6%.

Ménétrier's disease is giant hyperplasia of the gastric folds. The patients are often hypochlorhydric.

Pernicious anaemia, associated with atrophic gastritis, increases the risk of gastric carcinoma by a factor of 3.

The risk of gastric carcinoma in blood group A is increased by 16%-20%.

14

UC > Crohns disease signs

Ulcerative colitis begins in the rectum and progresses proximally. Conversely, the rectum is usually spared in Crohn's disease.

The characteristic finding in ulcerative colitis is continuous, fine mucosal ulceration with loss of the haustral pattern.

In Crohn's disease there are discrete and fissured ulcers. These often track deep into the bowel wall and may progress to sinus and fistula formation.

Strictures (often multiple) and skip lesions are also features of Crohn's disease.

15

Causes of toxic megacolon
PUS PA

Amoebic dysentery
Pneumatosis cystoides intestinalis
Pseudomembranous colitis
Salmonella gastroenteritis
Ulcerative colitis

Complications of amoebiasis include

Fulminant colitis
Stricture formation
Haemorrhage
Amoeboma
Amoebic liver abscess.
Pseudomembranous colitis is caused by Clostridium difficile and associated with antibiotic use. Symptoms vary from mild diarrhoea to fulminating toxic megacolon. Salmonella is also a recognised cause, particularly in children.

Pneumatosis cystoides intestinalis is associated with chronic bronchitis - multiple gas filled cysts in sub-mucosa of colon. It is mainly asymptomatic, but can cause abdominal pain, diarrhoea and rupture to produce pneumoperitoneum.

Salmonella enterocolitis produces colitis, acute appendicitis in young and mesenteric thrombosis in the elderly.

16

Regarding colon cancer AR/AD

In familial polyposis coli the increased cancer risk is due to inheritance of a mutated suppressor gene

Both familial polyposis coli and Gardner's syndrome are autosomal dominant.

An allelic deletion of a putative tumour suppressor gene on 5p.

Quantitative and qualitative alterations in gene expression accumulate in colorectal cancer cells. These include alterations of pro-oncogene expression and chromosomal abnormalities (deletions at 17p and 18q are seen in 70% of colorectal carcinomas).

Peutz-Jeghers syndrome is dominantly inherited pigmentation of skin and mucous membranes, and hamartomatous polyps in the stomach and larger intestine. The polyps only rarely undergo malignant change.

The rectum and sigmoid colon are the commonest sites.

17

Complications more in UC c.f. Crohns

Toxic megacolon can complicate Crohn's colitis, pseudomembranous colitis and infectious colitis, but is most commonly seen with severe UC.

Aphthous mouth ulcers are more common with Crohn's disease than UC but may be seen in up to 10% of patients with active UC.

Despite a widely held view to the contrary, there is good evidence that with the same duration and anatomic extent, the risk of colon cancer in Crohn's disease is at least as great as with UC. Only a small percentage of those with CD however have extensive colitis.

Gallstones are seen in 15-30% of patients with small bowel Crohn's disease, due to alterations in the bile salt pool secondary to ileal dysfunction +/- surgical resection.

Perianal fissures/fistulae/abscesses eventually occur in about one third of patients with Crohn's disease.

18

Coeliac disease associations

Oesophageal carcinoma is associated with coeliac disease, probably due to the malabsorption syndrome that leads to multiple nutritional deficiencies. There is an association with gastrointestinal lymphomas and, less commonly, adenocarcinoma (most often in the jejunum). Gastrointestinal hamartomas are associated with the hereditary Peutz-Jeghers syndrome.

Gluten-sensitive enteropathy is a disorder in which small bowel mucosal damage is the result of a permanent sensitivity to dietary gluten. The disorder does not present until gluten products have been introduced into the diet. Typically, the most common period of presentation is between six months and two years of age. Incidence is 1:10,000 live births.

Three components interact in the pathogenesis

Toxicity of certain cereals
Genetic predisposition
Environmental factors.
The disorder develops only after chronic dietary exposure to the protein gluten, which is found in wheat, rye, oats, and barley. The activity of gluten resides in the gliadin fraction which contains certain repetitious amino acid sequences (motifs) that lead to sensitisation of lamina propria lymphocytes.

The immunologic response to gluten results in villus atrophy, crypt hyperplasia, and damage to the surface epithelium in the small bowel. The injury is greatest in the proximal small bowel and extends distally for a variable distance.

The mode of presentation is variable; the majority present with diarrhoea. Children can have failure to thrive or vomiting as the only manifestation.

Perhaps as many as 10% of children referred to endocrinologists for growth retardation without an endocrine or overt gastrointestinal disorder have gluten sensitivity.

Anorexia is common and may be the major cause of weight loss or lack of weight gain.

Infants with gluten-sensitive enteropathy are often, but not always, clingy, irritable, unhappy children who are difficult to comfort. In contrast to infants with cystic fibrosis, they are not interested in food, although this is not always the case. Pallor and abdominal distension are common. Large, bulky stools suggestive of constipation have been described in some children with this condition. Digital clubbing can occur.

There is an increased prevalence of gluten-sensitive enteropathy in children with selective IgA deficiency or diabetes mellitus compared to unaffected children. Lymphocytic gastritis occurs in a rare child with gluten-sensitive enteropathy.

The most useful screening test for malabsorption is a microscopic examination of stool for fat.

The two antibody screening tests are: tissue transglutamine antibody (tTGA) and endomysial antibody (EMA).

Other initial studies should include a complete blood count, serum albumin, and serum immunoglobulin levels.

Nutrients that may be measured in blood include

Iron, the level of which depends on transferrin concentration as well as on absorption
Folic acid, the red cell concentration being a more accurate reflection of nutritional status than the serum concentration
Calcium and magnesium
Vitamin D and its metabolites
Vitamin A
Vitamin B12.

19

Causes of flattened small bowel mucosa

Not Crohns

Autoimmune enteropathy
Giardiasis
Milk protein intolerance
Transient gluten enteropathy

The mucosa in Crohn's disease depends on the severity. Initially there is superficial apthous ulceration. There may be subsequent florid ulceration and pseudopolyps. There is no flattening of the mucosa.

The diffuse lesion of the upper small intestinal mucosa that characterises coeliac disease is seen in a peroral suction biopsy specimen. Short, flat villi, deepened crypts, and irregular vacuolated surface epithelium with lymphocytes in the epithelial layer are seen by light microscopy. Similar abnormalities occur in other conditions but none is likely to be confused with coeliac disease.

Infections such as Rotavirus enteritis, Giardia lamblia, or tropical sprue can cause villus flattening and elongated crypts, but not the marked abnormalities of enterocytes.

A flat mucosa occurs in kwashiorkor but may represent a response to infestation rather than to undernutrition.

Tropical sprue, a poorly understood tropical enteropathy, can cause a lesion that is indistinguishable from that of coeliac disease.

Some cases of cow's milk protein or soy protein intolerance are associated with lesions similar to those of coeliac disease in children.

In immune deficiency and eosinophilic gastroenteritis, villi can be partially shortened. Infants with familial enteropathy have short villi, but the crypt dimensions are normal.

Autoimmune enteropathy is a poorly characterised syndrome of chronic diarrhoea and malabsorption.

If symptoms initially develop after the first 6 months of life, the disorder is likely to be mistaken for gluten-sensitive enteropathy.

Typically, the lack of response to a gluten-free diet leads to further evaluation. Histology findings in the small bowel include total villus atrophy, crypt hyperplasia, and an increase in chronic inflammatory cells in the lamina propria.

Specific serum anti-enterocyte antibodies may be identified with indirect immunofluorescent staining, using normal small-bowel mucosa and the kidney. The colon can also be involved.

Extra-intestinal autoimmune disorders are usual and include arthritis, membranous glomerulonephritis, thrombocytopenia, and haemolytic anaemia.

Treatment has included prednisone, azathioprine, cyclophosphamide (Cytoxan), and cyclosporine.

20

Hypertrophic pyloric stenosis

Hypertrophic pyloric stenosis occurs in approximately 3:1,000 live births. Males (especially first born) are affected approximately four times as often as females. Family clustering occurs.

Pyloric stenosis is associated with other congenital defects including tracheo-oesophageal fistula.

The vomiting usually starts after three weeks of age but symptoms may develop as early as the first week of life and as late as the fifth month.

Non-bilious vomiting is the initial symptom which progressively becomes more vigorous. As vomiting continues there is a progressive loss of fluid, hydrogen ion, and chloride, leading to a hypochloraemic metabolic alkalosis.

The diagnosis is established by palpating the pyloric mass. The mass is firm, movable, approximately 2 cm in length, olive shaped, hard, best palpated from the left side, and located above and to the right of the umbilicus in the mid-epigastrium beneath the liver edge.

Imaging procedures (USS or barium meal) are reserved for those infants in whom the diagnosis remains in doubt.

21

Infants with GORD

Infants with GOR usually present with

Failure to thrive
Vomiting
Recurrent pneumonias.
Older children may present with heartburn.

Severe oesophagitis may require proton pump inhibitors.

Barrett's ulcers result from chronic GOR causing metaplasia of oesophagus to gastric epithelium.

In children with recurrent croup with no infective symptoms, GOR should be considered.

Symptoms usually improve as the lower oesophageal sphincter tone improves with age.

22

Worse prognosis signs in pancreatitis

If a patient has an modified Imrie score of 2 or greater they are considered to have severe acute pancreatitis (which carries a mortality rate of 30%).

A CT scan of the abdomen should be performed on the third day after the onset of symptoms; findings which carry a worse prognosis are peri-pancreatic fluid or evidence of haemorrhage or necrosis.

Positive blood cultures are significant as they may represent infected pancreatic necrosis (mortality more than 50%).

There appears to be no difference in outcome depending on the aetiology, however alcoholics appear to have more attacks.

Imrie criteria age more than 55 and hypocalcaemia are both positive parameters.

23

Predisposing factors in oesophageal cancer

Excess alcohol is mainly associated with squamous cell carcinoma (SCC) of the oesophagus. Other factors in the development of SCC of the oesophagus are:

smoking
human papilloma virus
Plummer-Vinson syndrome, and
tylosis (autosomal dominant with a risk of 70%).
Cancer of the stomach is associated with:

blood group A
pernicious anaemia
partial gastrectomy
atrophic gastritis.

24

Foramen of Bochdalek and congenital hernias

Congenital diaphragmatic hernias occur in approximately 1 in 4,000 live births.

Ninety percent occur in the posterior portion of the diaphragm through the foramen of Bochdalek and 90% occur on the left.

The commonest clinical presentation is with respiratory distress in the neonatal period and due to pulmonary hypoplasia and compression. The abdomen often has a scaphoid appearance.

About 40% of patients have associated congenital anomalies.

The diagnosis can be confirmed radiologically with bowel loops seen in the chest.

Neonates usually require sedation, ventilation and intestinal decompression prior to surgery between 36 and 72 hours after birth.

25

Intussusception causes

Intussusception is the commonest cause of intestinal obstruction in the 6 to 18 months age group.

It often occurs in the distal ileum with an ileo-colic intussusception being the most common type.

Precipitants may include an inflamed Peyer's patch or a Meckel's diverticulum.

The infants usually present with

Severe intermittent colic
Bile-stained vomiting
Rectal bleeding
and 30% have a 'sausage-shaped' abdominal mass.

The diagnosis can often be confirmed by a 'doughnut' appearance on ultrasound.

26

Hirschsprungs disease

Hirschsprung's disease is a common cause of neonatal large bowel obstruction. It results from failure of migration of ganglion cells to the affected segment of bowel. This always involves the distal colon, but the proximal extent of the involvement is variable and in rare cases may involve the whole of the large bowel.

Histologically, the affected segment has absent ganglion cells in the Meissner's and Auerbach's plexus, but immunohistochemical evidence of increased angiotensin-converting enzyme (ACE) activity.

Eighty percent of cases present in the neonatal period.

Contrast studies show the affected segment to be tonically contracted.

Rectal irrigation or an emergency colostomy may be required before a definitive 'pull-through' procedure.

27

Subtotal villous atrophy associations

Subtotal villous atrophy may be associated with:

Coeliac disease
Dermatitis herpetiformis
Zollinger-Ellison syndrome
Giardiasis
Tropical sprue, and
Hypogammaglobulinaemia.
Delcò et al.1 write: "In 1962, Shiner and Drury reported partial and subtotal villous atrophy in 6 out of 11 patients with Crohn's disease. By contrast, Milewski et al could not find any villous atrophy in a group of 41 patients with regional enteritis. Subsequently, multiple case reports described the coexistence of celiac sprue with inflammatory bowel diseases, but none of these studies was able to provide statistical evidence for this association."

28

Moderate dehydration in baby

A moderately dehydrated baby has a loss of 6-9% of body weight and a fluid deficit of around 100 ml/kg.

Breast feeding should be continued and supplement oral feeds may be required to maintain adequate volumes.

Formula fed infants should not have their formula changed and milk feeding should not be discontinued.

Hyponatraemia or a normal serum sodium is more likely to be present than hypernatraemia.

Decreased skin tone and tissue turgor will be present, also oliguria, dry mucous membranes and sunken fontanelle.

29

Oesophageal cancer associations

Achalasia is a recognised factor, though rare. Another factor is hot herbal tea infusates.

Barrett's oesophagus is gastric metaplasia of the lower oesophagus.

Acids or alkalis through inflammation and scarring may be associated with a later development of cancer.

30

Causes of toxic megacolon

Toxic megacolon occurs typically in ulcerative colitis.

Known causes of toxic megacolon include

Crohn's disease
Pseudomembranous colitis
Amoebiasis
Salmonella enteritis
Campylobacter enteritis infection (particularly when antimotility agents are used)
Ischaemic colitis.

31

Structures encountered in inguinal hernia repair

Deep to the subcutaneous fat overlying the inguinal canal is the superficial fascia (also referred to as Scarpa's fascia). Scarpa's fascia allows the subcutaneous fat (Camper's fascia) to slide freely on movement.

Colles' fascia (superficial perineal fascia) is a continuation of Scarpa's fascia into the perineum.

The iliohypogastric nerve passes between the external and internal obliques piercing the external oblique aponeurosis approximately 2.5 cm above the superficial inguinal ring. This is usually above the area encountered during a normal inguinal hernia repair.

The coverings of the spermatic cord are

The external spermatic fascia (derived from the external oblique aponeurosis)
The cremasteric fascia and muscle (derived from the internal oblique and transversus aponeuroses and muscles) and
The internal spermatic fascia (derived from the transversalis fascia).
Just above the inguinal ligament the genitofemoral nerve splits into the genital branch (passes through the transversalis fascia and enters the spermatic cord) and the femoral branch (passes in front of the femoral artery).

32

Gastric ulcers

Peptic ulcers are caused by gastric acid and pepsin acting on the mucosa.

Eighty percent occur in the duodenum and 20% in the stomach. Most cases are associated with H. pylori (more than 80% with gastric ulcers, 95% with duodenal ulcers).

The majority of patients with duodenal ulcers have a high acid output, and the majority with gastric ulcers will have a normal or, sometimes, low acid output. About 1% of patients with H. pylori infection develop a pangastritis and hypochlorhydria which may increase the risk of gastric cancer.

Peptic ulceration may present

Electively, with symptoms such as nausea and intermittent epigastric pain
As an emergency, with an acute upper gastrointestinal (GI) bleed or perforation.
Duodenal ulcers are the commonest cause of upper GI bleed and may be treated endoscopically or surgically.

Ten percent of all gastric ulcers are malignant and a minimum of six biopsies should be taken from the edge of any gastric ulcers seen.

33

Causes of oesophageal cancer

Gastro-oesophageal reflux has a multi-factorial aetiology, but is predominantly due to failure of the lower oesophageal sphincter.

Caffeine and glyceryl trinitrate (GTN) cause relaxation of the smooth muscle at the gastro-oesophageal junction.

Stenting forms a mechanical barrier to normal LOS function and maintains non-functional patency.

H. pylori eradication may exacerbate GORD by an unknown mechanism. ;H. pylori may therefore be protective. The evidence remains uncertain.

No matter what the cause, dysfunction of the lower oesophageal sphincter allows reflux of the stomach contents into the oesophagus, giving rise to the symptoms of GORD.

34

Barretts oesophagus and p53

Barrett's oesophagus is when columnar epithelium lines the distal oesophagus, that is, when the squamo-columnar junction is more than 3 cm above the gastro-oesophageal junction.

Barrett's predisposes to the development of adenocarcinoma, with a 30-fold increase in these patients. It is associated with p53 over-expression early in carcinogenesis.

Some 30-70% of patients with high grade dysplasia (not metaplasia - intestinal metaplasia is the change that is described as Barrett's oesophagus) harbour foci of invasive carcinoma. High grade dysplasia may be considered an indication for oesophagectomy.

Treatment options of Barrett's include photodynamic therapy, which may be used to ablate areas of metaplasia, dysplasia or early carcinoma; but there is no evidence that a surgical antireflux procedure will reverse this metaplasia.

35

Concerning undescended testes

True undescended testicles are always associated with indirect inguinal hernias.

They are more common in preterm babies (incidence of 17% in low birth weight babies as compared to 4% in term infants).

Undescended testicles are not painful.

Retractile testes retract into the inguinal canal in response to an exaggerated cremasteric reflex. Consequently, when testes that were palpable become impalpable retractile testes are suspected. Often more than one examination is required to confirm the diagnosis.

If retractile, the testis adopts a permanent position in the scrotum by puberty, and does not have any of the associated complications of undescended testicles such as infertility and malignancy.

36

Pyloric stenosis

Congenital pyloric stenosis usually presents in male infants in the first two months of life. The electrolyte abnormality is characteristically hypochloraemic alkalosis (not hyperchloraemic), due to the loss of chloride and hydrogen ions during vomiting.

The initial response by the kidneys is to excrete alkaline urine (not acid), which also contains sodium and potassium ions. Conservation of water, sodium and chloride ions causes the kidneys to excrete potassium and hydrogen ions in exchange for sodium ions. The acidic urine exacerbates the alkalaemia resulting in hypokalaemia.

Performing a pyloromyotomy is not a surgical emergency, and it should be delayed until the infant has been fluid resuscitated and the biochemical profile normalised.

Acceptable plasma electrolyte values are

Chloride ions >90 mmol/l
Sodium ions >135 mmol/l
Bicarbonate ions s solution should be avoided in patients with metabolic alkalosis.

37

Enteral vs parenteral nutrition

Feeding by the enteral route (EN) is metabolically, immunologically, and nutritionally superior and financially less expensive, compared to feeding by the parenteral route.

The presence of bowel sounds has no influence on when to start enteral feeding. Many patients with absent bowel sound tolerate and absorb nasogastric feeds.

The only indication for TPN is inability to use or failure of the enteral route for nutritional support. TPN usually requires a dedicated central venous catheter (although peripheral intravenous feed is available), which can potentially get colonised by micro-organisms.

Abnormal liver function, cholestasis and trace element deficiency (copper, iron, chromium and especially zinc) are common problems associated with TPN.

38

Gluten free diet

From our feedback from previous examinees, it seems that questions about food in relation to medical conditions are popular in the examination.

Regarding coeliac disease, there are certain items that contain gluten that may not at first be obvious and should thus be avoided.

They include

Baking powder
Stock cubes
Mustard powder
Packet suet
Ready-grated cheese
Soy sauce
Dry-roasted nuts
Food that has been deep-fried with other gluten-containing foods
Processed meats
Flavoured crisps
Malted milk drinks
Pick-and-mix sweets.
However, many ingredients are safe. Naturally gluten-free cereals include

Rice flour
Tapioca flour
Potato flour
Corn flour
Cornmeal
Soya flour
Gram flour
Buckwheat flour.
There are a number of others but these are the most widely available.

39

Metoclopramide effects

Metoclopramide causes increased GI motility, increases sphincter tone and also has central anti-emetic actions mediated through dopaminergic receptors.

40

Ondansetron mechanism of action

Ondansetron is a 5-HT antagonist and a particularly effective anti-emetic.

Domperidone/metoclopramide's actions are mediated through antagonism of the dopaminergic receptors.

41

APC

The APC gene is on chromosome 5q distal to 5'. Inheritance is autosomal dominant.

The average onset of colorectal cancer is 39 years. Because many cases present earlier, baseline flexible sigmoidoscopy is offered from 10-12 years of age with annual screening thereafter.

Gastroscopy is performed three yearly once colonic polyps are present due to gastric and small bowel polyp formation.

Treatment is total colectomy with ileo-anal pouch formation, or ileostomy for multiple polyps, usually in the patient's early twenties.

Family screening is important.

The attenuated form of the disease (also AD inheritance, Chr 5q proximal to 5') presents with fewer polyps and flat adenomas with a proximal predilection. Onset of colorectal cancer (CRC) is later, at a mean of 50 years.

Osteomata of the mandible are one feature of Gardener's variant of APC. Others include

Epidermoid cysts of the skin
Congenital pigmentation of the retinal pigment epithelium.
APC is also associated with intra-abdominal desmoid tumour formation. The tumours do not tend to metastasise, but cause local complications which can be fatal.

Neither protein losing enteropathy, nor white nails are part of the clinical spectrum of APC.

42

Arthritis and GI disease

Coeliac disease is well recognised to be associated with arthropathy.

A distal small joint arthropathy is associated with primary biliary cirrhosis (PBC).

Pyoderma gangrenosum is associated with both ulcerative colitis (UC) and Crohn's disease. The arthropathy is typically large joint (knee and ankle) and/or sacroiliitis/ankylosing spondylitis. Pyoderma gangrenosum is also seen in rheumatoid disease.

In Whipple's disease there is acute, migratory and transient arthropathy, which commences distally first and usually precedes intestinal symptoms.

43

Increased incidence of peptic ulcer with

Peptic ulceration occurs with increasing frequency in association with

Drugs, such as steroids and non-steroidal anti-inflammatory drugs (NSAIDs)
Hyperparathyroidism
Certain blood groups, such as O and A
Family history
Cigarette smoking
H. pylori
Chronic renal failure
Renal transplantation
Systemic mastocytosis
HLA-B5.

44

PSC

Primary sclerosing cholangitis, which primarily affects middle aged men, is caused due to persistent inflammation and scarring of the bile ducts.

With progressive scarring, the ducts become blocked. The patient presents with right upper quadrant pain, jaundice, fever, pruritus, nausea and vomiting.

Although the aetiology remains unclear, it may be associated with inflammatory bowel disease such as ulcerative colitis.

45

Primary haemachromatosis

Primary haemochromatosis, also termed hereditary haemochromatosis or idiopathic haemochromatosis, is an autosomal recessive disorder and is more common in men.

There is increased absorption of iron from the gut and progressive increase in the total body iron stores with abnormal iron deposition in multiple organs, primarily the liver. Liver dysfunction may lead to cirrhosis and even hepatocellular carcinoma in about 30% of cases.

The patient may present with:

right upper quadrant pain
hepatomegaly
slatey-grey skin pigmentation
arthritis
lethargy
impotence, and
testicular atrophy.
Cardiac involvement causes cardiomyopathy and arrythmia which is an important cause of death in patients with primary haemochromotosis.

46

Hepatocellular carcinoma

Hepatocellular carcinoma (also known as malignant hepatoma) is the primary cancer of liver. Hepatitis B infection is a risk factor for hepatocellular carcinoma.

Patients may present with:

pain over the right hypochondrium
hepatomegaly
anorexia
jaundice
loss of appetite, and
rapid loss of weight.
As the disease progresses, the patient develops ascites and may experience pain radiating to the back and the shoulder (due to irritation of the undersurface of the diaphragm). Patients may also present with signs of upper gastrointestinal bleed due to oesophageal varices.

47

Coeliac disease associations

Coeliac disease leads to an increased risk of both adenocarcinoma and lymphoma of the small bowel, which return to baseline with diet.

Longstanding disease may lead to other complications such as ulcerative jejunitis and stricturing. The changes in the bowel make it less able to absorb nutrients, minerals and the fat-soluble vitamins A, D, E, and K.

Coeliac disease has been linked to

Dermatitis herpetiformis
Epilepsy
Ataxia
Myelopathy
Peripheral neuropathy
Malnutrition
Hyposplenism
Diabetes mellitus type 1
Autoimmune thyroiditis
Primary biliary cirrhosis.