01-02-23 - The Physiology of Gastrointestinal Disorders Flashcards
Learning outcomes
- To consider the GIT problems that patients with complex neurodisability may have and how to manage them.
- To have a working knowledge of the presentation and management of some important conditions affecting the Gastrointestinal Tract including Coeliac Disease, Acute Pancreatitis and Hirschsprung disease.
- To consider the relevance of GIT Physiology to Toilet Training in children.
- To consider the causes of vomiting in infants in particular.
- To be able to differentiate the plain x ray appearances of the different types of bowel obstruction.
What are 7 GI problems in neurodisability?
- 7 GI problems in neurodisability:
1) Feeding problems
2) Swallowing difficulties
3) Saliva control
4) Constipation
5) Gastroparesis (food passes through the stomach slower than it should)
6) GI reflux
7) Regular review of nutrition
What is Sialorrhea?
In what conditions can we see Sialorrhea?
What can it cause?
What medications are needed?
- Sialorrhea is additional saliva/drooling
- We may see sialorrhea in children and adults with cerebral palsy & complex neurodisability
- The excess saliva can cause skin problems
- Anticholinergic medication can be used: Trihexyphenidyl hydrochloride, glycopyrrolate
What are 9 side effects of anti-cholinergic medications?
- 9 side effects of anti-cholinergic medications:
1) Drowsiness or sedation
2) Blurred vision
3) Dizziness
4) Urinary retention
5) Confusion or delirium
6) Hallucinations
7) Dry mouth
8) Constipation
9) Reduced sweating and elevated body temperature
Where are Transdermal scopolamine patches (Scopoderm TTS)?
How do they work?
- Transdermal scopolamine patches (Scopoderm TTS) are placed behind the ear, at the mastoid process.
- The patch releases a sustained dose of 0.5 mg of scopolamine (hyoscine) per day and must be changed every 72 hours, alternating between the right and left sides.
How can botulinum injections be used to treat sialorrhea in children with neurologic disorders?
- Ultrasonography-guided Botulinum Toxin type A injections into bilateral parotid and submandibular glands is a safe and effective treatment for sialorrhea in children with neurologic disorders
What are 3 methods for administering nutrition in those with GI disorders?
- 3 methods for administering nutrition in those with GI disorders:
1) Percutaneous Endoscopic Gastronomy (PEG)
* Bolus or continuous
* Food for pleasure
* Specialist nurses/family training.
2) Button
3) Jejunal feeding tube feeding
* Gastroporesis (food passes through the stomach slower than it should)
* Bolus or continuous
* Food for pleasure
* Specialist nurses/family training.
Jejunal feeding tube feeding diagram
What is coeliac disease?
What part of the body does it affect?
What 3 things occur due to the reaction to gluten?
How prevalent is coeliac disease?
What foods contain gluten?
- Coeliac disease is an autoimmune condition that results in the reaction to gluten
- Coeliac disease affects the small intestine
- 3 things occur due to the reaction to gluten:
1) Inflammation from production of IgA antibodies
2) Difficult for them to digest food and absorb nutrients.
3) Malabsorption - Prevalence of coeliac disease is 1:100 (36% are diagnosed)
- Gluten is found in foods that contain wheat, barley and rye (such as bread, pasta, cakes and some breakfast cereals)
- Bread, cakes, biscuits, pizzas, cereals, and beers and ales.
- Many ready meals, soups, sauces, and sausages also contain wheat flour
What 10 symptoms might lead to us testing for coeliac disease?
- 10 Symptoms that might lead to us testing for coeliac disease:
1) Persistent unexplained abdominal and gastrointestinal symptoms
2) Faltering growth
3) Prolonged fatigue
4) Unexpected weight loss
5) Severe or persistent mouth ulcers
6) Unexplained iron, vitamin B12, or folate deficiency
7) Type 1 Diabetes (at diagnosis)
8) Symptoms of irritable bowel syndrome (abdominal pain, bloating, and/or altered bowel habit) in adults
9) Autoimmune thyroid disease
10) First degree relatives (parents, siblings, or children) of people with coeliac disease
In what 7 situations might we test for coeliac disease?
- 7 situations might we test for coeliac disease:
1) Metabolic bone disorder (reduced bone mineral density or osteomalacia)
2) Unexplained neurological symptoms (particularly peripheral neuropathy/ataxia)
3) Unexplained subfertility or recurrent miscarriage
4) Persistently raised liver enzymes with unknown cause
5) Dental enamel defects
6) Down syndrome
7) Turner syndrome - Turner syndrome, a condition that affects only females, results when one of the X chromosomes (sex chromosomes) is missing or partially missing
How does serological testing as an indication for coeliac disease work?
What can this test be used for?
- Serological testing:
- Request total immunoglobulin A (IgA) and IgA tissue transglutaminase (IgA tTG) for serological testing
- A positive serological result is an unequivocally raised IgA tTG.
- If IgA tTG is weakly positive or total IgA is deficient the lab will do further testing.
- This test does not diagnose coeliac disease, but indicates whether further gastroenterology assessment
How do we diagnose coeliac disease?
- To diagnose coeliac disease, we refer all patients with positive serology or those with negative serology but clinically suspected to GI
- A positive serological test is not diagnostic of coeliac disease and a duodenal biopsy should be used for definitive diagnosis
Why is a combination of positive serology and symptom relief following gluten exclusion not a definitive diagnosis for coeliac disease?
- A combination of positive serology and symptom relief following gluten exclusion is not diagnostic of coeliac disease because presenting symptoms might be related to another disorder responding to gluten withdrawal e.g. irritable bowel syndrome.
What are 2 complications of coeliac disease?
- 2 complications of coeliac disease:
1) Malignancy, especially lymphoma
2) Osteoporosis
What 13 foods are naturally free of gluten?
- 13 foods that are naturally free of gluten:
1) Rice
2) Potatoes
3) Polenta
4) Quinoa
5) Millet
6) Unprocessed meat
7) Eggs
8) Fish
9) Milk cheese
10) Fruit
11) Vegetables
12) Beans
13) most yoghurts
What do oats contain that is similar to gluten?
How can this affect those with coeliac disease?
When should oats be eaten by those with coeliac disease?
- Oats do not contain gluten but they do contain the protein avenin which is similar to gluten.
- Some people with coeliac disease can react to avenin in the same way they would react to gluten.
- Oats are often processed in the same environment as gluten containing products (wheat, barley, and rye) and are easily cross contaminated.
- Only eat oats certified as being gluten free
What are 4 Tasks in the annual review of a patient with Coeliac Disease?
- 4 Tasks in the annual review of a patient with Coeliac Disease:
1) Measure weight and height; calculate BMI
2) Review symptoms
3) Consider the need for assessment of diet and adherence to the gluten free diet
4) Consider the need for specialist dietetic review and nutritional advice
What is Dermatitis Herpetiformis (DH).
What % of those with coeliac disease have DH?
How many people without coeliac disease are affected by DH?
What ages doe sit commonly affect?
- Dermatitis Herpetiformis (DH) is a Skin condition linked to coeliac disease
- 15-20% of people with coeliac are affected with DH
- Affects fewer people than typical coeliac disease, at around 1 in 3,300 people.
- Any age can be affected, but is most commonly between 50 and 69 years.
What are 4 symptoms of DH?
- 4 symptoms of DH:
1) Red, raised patches, often with blisters that burst with scratching
2) Severe itching and often stinging
3) The rash is most commonly seen on the elbows, knees and buttocks, but any area of the skin can be affected
4) The rash usually occurs symmetrically on the body
How is Dermatitis Herpetiformis (DH) diagnosed?
Why is treatment for DH used?
What treatment can be used for DH?
- Dermatitis Herpetiformis (DH) diagnosis is confirmed by skin biopsy.
- As it can take a long time for a gluten-free diet to take effect, drug treatment is used to help control the rash to begin with.
- The most common drug prescribed is Dapsone.
- Steroids can also be prescribed (topical or systemic)
What is acute pancreatitis triggered by?
How common is it in the west and around the world?
What % of surgical admissions are for acute pancreatitis?
What are the 2 most common causes of acute pancreatitis?
How often does this condition occur in children?
- Acute pancreatitis is triggered by release of activated exocrine enzymes into the substance of the organ.
- t is relatively common and has shown a 10 fold increase in many Western countries in the last two decades.
- Annual incidence varies in different parts of the world.
- Acute pancreatitis accounts for approximately 1% of acute surgical admissions.
- Alcohol abuse and gallstone migration are the most common causes with the latter being more common in women than in men. (90%)
- The condition is rare in children
What is Cullen’s sign?
What is it the result of?
How often is it associated with pancreatitis?
How does Cullen’s sign occur in pancreatitis?
- Cullen’s sign is periumbilical ecchymosis (A small bruise caused by blood leaking from broken blood vessels into the tissues of the skin or mucous membranes)
- It is the result of tracking of blood from the retroperitoneum to the umbilicus along the gastrohepatic and falciform ligament to subcutaneous umbilical tissues through the connective tissue covering of the round ligament.
- < 3% of patients with pancreatitis have Cullen’s sign
- In the patient in the picture, it was associated with acute pancreatitis and a result of liberated pancreatic enzymes causing the diffusion of fat necrosis and inflammation with retroperitoneal or intra-abdominal bleeding.
What is Grey Turner’s sign produced by?
What % of pancreatitis cases is it associated with?
- Grey Turner’s sign is produced by haemorrhagic fluid spreading from the posterior pararenal space to the lateral edge of the quadratus lumborum muscle and thereafter to the subcutaneous tissues by means of a defect in the fascia of the flank.
- It is associated with severe acute pancreatitis and a high mortality ( <1%)
What can be indicated if new-born vomiting after birth is persistent?
What could certain maternal disorders indicate in the new-born?
What does bile -stained emesis suggest?
- When vomiting occurs shortly after birth and is persistent, the possibilities of intestinal obstruction and increased intracranial pressure must be considered
- A history of maternal polyhydramnios (too much amniotic fluid) suggests upper gastrointestinal (esophageal, duodenal, ileal) atresia
- Bile -stained emesis suggests intestinal obstruction beyond the duodenum and requires investigation –this is an emergency
What is duodenal atresia?
How is diagnosis confirmed?
When can duodenal atresia be detected?
How is it treated?
- Duodenal atresia is a congenital defect that results in the duodenum being closed off
- Upright abdominal film showing the characteristic “double-bubble” sign that confirms the diagnosis
- Duodenal atresia can be detected antenatally (before the baby is born)
- It is treated with surgery
When can new-borns vomit blood-streaked mucus?
How long does it persist?
What might it be caused by?
- Infants may vomit mucus, occasionally blood-streaked, in the first few hours after birth
- This vomiting rarely persists after the first few feedings
- It may be due to irritation of the gastric mucosa by material swallowed during deliver
What occurs in the gut of the embryo at 6 weeks gestation?
What occurs to the intestines at 10-12 weeks?
Describe the attachment of the small bowel mesentery
- At 6 weeks gestation in the normal embryo, physiologic herniation of the gut through the umbilicus is accompanied by a 270 ° counter clockwise rotation of the developing intestine around the superior mesenteric artery
- By 10-12 weeks, the intestine returns to the abdomen and assumes its normal
adult anatomic position. - Normal small bowel mesentery has a broad attachment stretching diagonally from the duodenojejunal junction (in the left upper quadrant) to the caecum (in the right lower quadrant).
What are 3 Malrotation intestinal obstruction?
- 3 Malrotation intestinal obstruction:
1) Obstruction of the duodenum
* May result from congenital peritoneal bands (Ladds bands) which run over the duodenum from the caecum in the right upper quadrant.
2) A midgut Volvulus
* Twisting of the gut around itself and the mesentery that supplies it, causing a bowel obstruction
3) Internal hernia in the mesentery
At what time can hypertrophic pyloric stenosis (HPS) occur?
What occurs to milk consumed?
When can vomiting begin?
- Hypertrophic pyloric stenosis (HPS) can occur at 4-6 weeks
- Milk consumed stayed in the stomach, then is brought all back up
- The vomiting may begin any time after birth but does not assume its characteristic pattern before the 2nd to 3rd week (projectile vomiting)
How many new-borns are affected by HPS?
What infants is it more and less likely to affect?
What race of new-borns is it more likely to affect?
What % of infants born with HPS have a family history of the condition?
- HPS affects three out of every 1,000 babies born
- It is more likely to affect full-term, first-born male infants and affects female infants less frequently.
- HPS is more common in Caucasian infants.
- About 15 percent of infants born with HPS have a family history of the condition.
How is HPS diagnosed?
Diagnosis of HPS – Contrast study and Ultrasound (used now)
HPS is now diagnosed through ultrasound
How can HPS be treated?
- HPS can be treated with a Pyloromyotomy, which divides the hypertrophic muscle
What are the small bowel mucosal folds called?
Where do they start to appear?
How do they differ as they go along the small intestine?
How does this make them appear on scans/tests?
- Small bowel folds also known as Kerckring folds (aka plicae circulares) are the mucosal folds of the small intestine.
- Starting from the second part of the duodenum, they are large and thick at the jejunum and considerably decrease in size distally in the ileum to disappear entirely in the distal ileal bowel loops
- They result in a classical appearance on abdominal radiographs, barium studies and CT scans
What % of bowel obstructions occur in the small intestine?
How is it caused?
What appearance does this give?
Is it congenital or acquired?
What is the most common cause of small bowel obstruction in developed and developing countries?
What are these frequent causes for?
- Small bowel obstruction accounts for 80% of all mechanical intestinal obstruction with the remaining 20% result from large bowel obstruction
- Small bowel obstruction is caused by the bowel filling with air and fluid, producing a ‘stack of coins’ appearance
- Causes can be divided into congenital and acquired, with acquired causes being extrinsic, intrinsic or luminal
- In developed countries, adhesions are by far the most common cause of small bowel obstruction, accounting for ~75% of obstructions
- In developing countries incarcerated hernias are much more common accounting for 80% of obstructions.
- These are frequent causes for surgical admission.
What is the large intestine?
What is the first and second most common cause of large bowel obstruction in adulthood?
Where does it typically occur?
What is diverticulitis?
How can small and large bowel obstruction causes differ?
- The large intestine is a 1.5 metre muscular tube that extends from the caecum to the rectum
- In adulthood, the most common cause of obstruction is colonic cancer (50-60%), typically in the sigmoid.
- The second most common cause in adults is acute diverticulitis of the sigmoid colon.
- Diverticulitis is inflammation of outpouchings of the large bowel.
- While adhesions are the leading cause of small bowel obstruction, for practical purposes, they do not tend to cause large bowel obstruction
What is a Paralytic ileus?
What 3 symptoms do patients with paralytic ileus present with?
How are bowel sounds altered with paralytic ileus?
What presentation can be seen on radiographs for Paralytic ileus?
- Paralytic ileus is a functional intestinal obstruction without an actual physical obstruction (neuromuscular failure)
- 3 symptoms do patients with paralytic ileus present with:
1) Nausea/vomiting
2) Distension
3) Reduced or absent bowel movements (No abdominal pain. No flatus.) - Bowel sounds will be decreased / absent whereas they are increased in mechanical obstruction.
- Generalised, uniform, gaseous distension of the large and small bowel is evident on radiographs of Paralytic ileus
How can paralytic ileus be distinguished from small bowel obstruction?
What is the cause of ileus thought to involve?
What are the 5 common causes of paralytic ileus (5Ps)?
- The involvement of small & large bowel and lack of a transition point on plain radiographs help distinguish paralytic ileus from mechanical small bowel obstruction
- The cause of ileus is thought to be complex and multifactorial, involving bowel inflammation, inhibitory neural reflexes, and neurohormonal peptides
- 5 common causes of paralytic ileus (5Ps):
1) P: postoperative
2) P: peritonitis
3) P: potassium: low
4) P: pelvic and spinal fractures
5) P: parturition (child birth)
What is Hirschsprung disease the most common cause of?
How is it characterised?
How many live births are affected by Hirschsprung disease?
Where is it rarely seen?
- Hirschsprung disease is the most common cause of neonatal colonic obstruction
- It is commonly characterised by a short segment of colonic aganglionosis affecting term neonates, especially boys
- Hirschsprung disease affects approximately 1:5000- 8000 live births.
- Interestingly, it is almost never seen in premature infants
In what group does Hirschsprung disease typically present in?
What is a sign of this?
What % of cases are present within six weeks of birth?
What % of cases are present within 5 years of life?
Can it present in the adult population?
What is needed for a definitive diagnosis of Hirschsprung disease?
- The condition typically presents in term neonates, with failure to pass meconium (first poop) in the first 1-2 days after birth
- Later presentation is also common
- Overall ~75% of cases present within six weeks of birth
- Over 90% of cases present within the first five years of life.
- A very small number may present in the adult population
- A definitive diagnosis of Hirschsprung disease requires a full thickness rectal biopsy
What is the surgical treatment for Hirschsprung disease?
How is the prognosis?
How can complications affect this?
How high can mortality rates be due to enterocolitis?
- Surgical treatment for Hirschsprung disease is the removal of the affected portion of the colon
- Where this is successful, the prognosis is good.
- However, in 3-4% of cases colonic perforation complicates the presentation and the surgery, with its sequelae significantly increasing both mortality and morbidity.
- Mortality rates from surgery can be as high as 30% due to enterocolitis (inflammation of both intestines at once)
