Gastrointestinal conditions Signs, causes And Differentials Flashcards by XXXXX XXXX

Q

What are the causes of metabolic acidosis?

A

Diabetic ketoacidosis (ketones produced are acidic)

Lactic acidosis (increased acid production)

Renal failure (reduced acid secretion)

Chronic diarrhoea (bicarbonate loss)

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

What are the causes of metabolic alkalosis?

A

Increased alkali ingestion

Vomiting

Potassium depletion

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

What is irritable bowel syndrome?

What are the subtypes?

A

A chronic condition primarily manifesting as a syndrome of colicky abdominal pain, bloating and altered bowel habit.

Types:

Diarrhoea predominant

Constipation predominant

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

What are the signs of irritable bowel syndrome?

A

Presentation is variable

Colicky abdominal pain anywhere in abdomen, can be severe pain
(colic = pain that abruptly comes and goes with peristaltic motions)
Abdominal bloating
Constipation, diarrhoea or alternating between the two
Faecal incontinence
Urgency
Exaggerated gastro-colonic reflex (every time you eat, you defaecate)
Anxiety about eating
Bloating (can go up 2 dress sizes)

Extra-intestinal symptoms:

Nausea
Thigh pain
Back ache
Lethargy
Urinary symptoms
Gynaecological symptoms - commonly dyspareunia

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

What are the differentials for acute abdominal pain?

A

Peritonitis

Ruptured AAA

Hepatic/pancreatic/biliary:
Cholecystitis
Common bile duct stones 
Cholangitis
Acute pancreatitis

GI:
Bowel obstruction
Acute mesenteric ischemia
Gastro/duodenal ulcer
Diverticulitis
Gastroenteritis
Constipation 
IBD - chrons disease or ulcerative colitis
Strangulated hernia
Adhesions
Appendicitis

Renal:
Pyelonephritis
Renal colic

Hepatic:
Hepatic abscess
Hepatitis

Reproductive:
Ectopic pregnancy 
Testicular torsion
Ovarian cyst rupture or torsion or haemorrhage
Pelvic inflammatory disease 
Pregnancy

Cardiac:
MI

Haematological:
Sickle cell crisis
DKA
Addisonian crisis
Hypercalcemia

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

Which two patient groups are most at risk of mesenteric ischemia?

A

The elderly - CAD means thrombosis is likely

Those in AF - blood stasis means embolism is likely

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

What is mesenteric ischemia?

A

The blockage or occlusion of bowel arteries, often the superior mesenteric artery, nearly always the small intestines are the location.

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

What are the causes of mesenteric ischemia?

A

Superior mesenteric artery thrombosis (35% of cases)

Superior mesenteric artery embolism (35% of cases)

Non-occlusive disease (poor cardiac output)

Mesenteric vein thrombosis

Trauma

Vasculitis

Radiotherapy

Strangulation - herniated bowel or volvulus (twisted bowel)

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

What are the cardinal symptoms of acute mesenteric ischemia?

A

Often asymptomatic - they look well, pain is the only real symptom

Acute, severe abdominal pain

Pain is in the centre of the abdomen or right iliac fossa

Constant pain

Rapid hypovolaemia and shock

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

What are the cardinal symptoms of chronic mesenteric ischemia?

A

Severe colicky abdominal pain (-peristalsis against ischemic area)

Post-prandial pain (-pain upon increasing)

Weight loss (-due to chronic pain on eating)

Potentially plus:
N and V
Abdominal bruit
PR bleeding
Malabsorption

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

What is the major cause of chronic mesenteric ischemia?

A

Coronary artery disease (CAD)

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

By which pathophysiological mechanisms does H. Pylori cause increased acid production?

A

It tends to infect the antrum of the stomach, and therefore causes inflammation to the local cells:

Inflammation increases gastrin production (more acid production)
Inflammation suppresses D cell action (less somatostatin, less parietal cell inhibition)
Inflammation directly induces increased parasympathetic stimulation (increases acid production)

(There is also evidence that the bacteria feeds on mucosal surfactant)

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

What are the two main causes of gastric ulcers?

A

NSAIDs

H.Pylori infection

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

What are the symptoms of a gastric (peptic) ulcer?

A

Burning/gnawing pain in your upper abdomen, that can radiate to the back or inferiorly

Pain is usually related to eating

Epigastric tenderness

Potentially:
Indigestion
Heartburn
Bloating after fatty foods
Nausea and vomiting
Early satiety
Weight loss
Diarrhoea
GI bleeds
Anaemia symptoms (fatigue,pallor)

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

What is a gastroduodenal/peptic ulcer?

A

Lesions in the lining of the gastrointestinal mucosa due to the action of pepsin and stomach acid.

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

What are the differentials for a burning pain in the epigastrium?

A

Gastritis
Pancreatitis
Cholecystitis
Hepatitis
Peptic ulcer (Perforated)
IBS
IBD
Gastroenteritis
Mesenteric ischemia
Gastric cancer

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

By which mechanisms do NSAIDs damage the gastric lining?

A

Cytotoxic effect on epithelial cells (direct damage)
Inhibition of COX-1 enzyme
- decreased mucus production (decreased barrier - most important part!)
- decreased epithelial blood flow (decreased repair)
- suppress prostaglandin production (no effect of prostaglandins to decrease acid production)
Inhibition of COX-2 enzyme
- decreased angiogenesis
- suppress prostaglandin production (no effect of prostaglandins to prevent neutrophil adherence; mucosal damage results)

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

What does haematemesis look like?

A

May be bright red (think varices)

May be dark brown, like coffee grounds (think digested blood - bleeding peptic ulcer)

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

What symptoms might we seen in complications of peptic ulcers?

A

Fatigue (- iron deficiency anaemia)

Palpitations (- iron deficiency anaemia)

Dyspnoea (- iron deficiency anaemia)

Coffee ground vomit (- haematemesis of digested blood)

Melaena (- black, tarry stools)

Tachycardic (- Haemorrhagic shock)

Collapse/LOC (- Haemorrhagic shock)

Pale (- Haemorrhagic shock)

Agitation (- Haemorrhagic shock)

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

What are the symptoms of gastric outlet obstruction?

A

A clinical syndrome characterised by:

Epigastric pain

Postprandial vomiting (-due to mechanical obstruction)

Early satiety

Fullness

Bloating

Weight loss

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

What are the differentials for gastroparesis? (epigastric pain, postprandial vomiting)

A

Gastroduodenal ulcers (healing or active)

Gastric cancer

Pancreatitis

Small bowel obstruction

Narcotic bowel syndrome

Functional dyspepsia

Gastric outlet obstruction

IBS

IBD - chrons or ulcerative colitis

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

What are the causes of gastric outlet obstruction?

A

Peptic ulcer disease (- antrum scarring causing obstruction)

Pancreatic carcinoma (- extending into the duodenum/gastric outlet)

Gastric carcinoma (- uncommon, present like peptic ulcer disease, picked up mostly on biopsy)

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

What are the symptoms of gastric cancer?

A

Persistent indigestion

Trapped wind

Dyspepsia:
upper abdominal pain
fullness
early satiety
bloating
nausea

Melaena

Loss of appetite

Fatigue

Weight loss

Anaemia: Fatigue, Dyspnoea, Pale

Jaundice

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

What is gastro-oesophageal reflux disease?

A

Symptoms or complications that result from the reflux of gastric contents up in to the oesophagus/oral cavity/lung.

Basically: retrograde movement of food

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

What are the complications of GORD?

Oesophagus: Ulcer Haemorrhage Perforation Oesophageal stricture Barrett’s oesophagus Adenocarcinoma of the oesophagus

What are the signs of gastric cancer?

Epigastric mass Hepatomegaly Ascites Jaundice Troisiers sign Acanthrosis nigricans

Which medications are linked with peptic ulcers and GI bleeds? - 6 main categories -

Antiplatelets Corticosteroids NSAIDs Anticoagulants Nicorandil (-potassium channel activator: causes refractory bleeds, only stop when nicorandil is stopped) SSRIs

What are the common differentials for fresh blood in the stool?

Fresh bleeding usually suggests the rectum or anal canal as the source of blood (if the bleed is further up the tract the blood becomes MIXED in with the stool); Haemorrhoids Acute anal fissure (-trauma/constipation) Colorectal tumours (-benign or malignant) Acute proctitis IBD (-ulcerative colitis can start as proctitis)

What is an acute anal fissure?

A break/tear in the anal canal (i.e. NOT the rectum). A common condition because the cause is often constipation - a very common condition. Location: normally extend from the anal opening backwards IN (posteriorly in) to the anal canal, usually midline. The anal wall in the posterior midline is weaker and prone to tears. Severity - the tear can extend down in to the underlying sphincter muscles

What are the symptoms of an anal fissure?

Severe pain in the anus - often when passing hard stools (ask about constipation); Bright red anal bleeding - ask if any seen in toilet or on toilet paper Anal fissure bleeding is never enough to cause anaemia.

What is a GI diverticulum?

An outpouching of the gut wall, generally at areas where perforating arteries (the arteries supplying the colon) enter; weak points. Location: Colonic - most often the sigmoid colon, but can be in other parts of the GI tract MOA: High pressure inside the lumen forces the mucosa to herniate through the muscular layer. Note: 30% of people have diverticula by age 60, but most are ASYMPTOMATIC, they only have “diverticular disease” if the diverticuli are symptomatic

What is diverticulosis?

The presence of diverticula.

What is diverticulitis?

Inflammation of a diverticula.

What is diverticular disease?

A symptomatic diverticula.

What are the symptoms of diverticular disease?

Altered bowel habit Left sided (LIF or hypogastrium) colic pain relieved by defacation Nausea Flatulence

What are the symptoms of diverticulitis?

``` Same as diverticular disease: Altered bowel habit Left sided colic pain relieved by defacation Nausea Flatulence ``` Plus the inflammatory symptoms: Pyrexia Tender colon Localised/general peritonism Signs: Raised WCC/CRP

What is an acute abdomen?

An acute abdomen is a condition of severe abdominal pain, usually requiring surgery and caused by an acute disease/injury to internal organs. It is distinct from chronic abdominal pains. Examples of conditions within “acute abdomen”; Acute pancreatitis Duodenal ulcer Ectopic pregnancy

Which conditions cause acute abdomen of the RUQ? Note: RUQ doesn’t include the epigastrium, the epigastrium is a small area, bounded by the uppermost part of the costal arch, it also doesn’t include the umbilicus.

``` Acute cholecystitis Duodenal ulcer Pyelonephritis Right sided Pneumonia referred pain Hepatitis Congestive hepatomegaly ```

Which conditions cause acute abdomen of the LUQ? Note: LUQ doesn’t include the epigastrium, the epigastrium is a small area, bounded by the uppermost part of the costal arch, it also doesn’t include the umbilicus.

``` Ruptured spleen Pneumonia referred pain Gastric ulcer Aortic aneurysm Perforated colon Pyelonephritis Left sided pneumonia - referred pain ```

Which conditions cause acute abdomen of the RLQ? Note: RLQ doesn’t include the epigastrium, the epigastrium is a small area, bounded by the uppermost part of the costal arch, it also doesn’t include the umbilicus.

``` Acute appendicitis Chron’s disease Meckel’s Diverticulitis - small intestine, congenital Constipation Renal colic - renal/ureteric stone Strangulated hernia ``` ``` Reproductive: Ectopic pregnancy Ruptured ovarian cyst Ovarian abscess Salpingitis ```

Which conditions cause acute abdomen of the LLQ? Note: LLQ doesn’t include the epigastrium, the epigastrium is a small area, bounded by the uppermost part of the costal arch, it also doesn’t include the umbilicus.

``` Sigmoid Diverticulitis Constipation Strangulated hernia Chron’s disease Ulcerative colitis Renal colic - renal/ureteric stones ``` ``` Reproductive: Ectopic pregnancy Ruptured ovarian cyst Ovarian abscess Salpingitis ```

Which conditions cause acute abdomen of the Epigastrium?

``` Peptic ulcer Acute pancreatitis MI Acute cholecytitis Perforated oesophagus ```

Which conditions cause acute abdomen of the Umbilicus?

Early appendicitis - pain begins centrally and travels to the RIF Small bowel intestinal obstruction Acute pancreatitis Mesenteric thrombosis (mesenteric ischemia) Diverticulitis Aortic aneurysm

Which conditions cause acute abdomen of the Suprapubic quadrant?

Acute urinary retention UTI Ectopic pregnancy

Which conditions cause acute abdomen across the entire abdomen?

Perforated viscous Acute pancreatitis Diabetic ketoacidosis (- gastric distension, hypovolaemia and electrolyte disturbance)

What are the signs of acute abdomen?

``` Fever (- low grade) Tenderness Rigidity Guarding Rebound tenderness Abdominal distension (- fluid;ascites or gas due to obstruction or foetus in women) ``` Bowel sound change: Absent - peritonitis Increase sounds/high pitched tinkling - small bowel obstruction

Why does normal constipation occur in the descending/sigmoid colon more often?

The ascending colon is processing liquid stool direct from the ileum, the stool has not had the opportunity to be dehydrated and compressed yet. This means constipation normally occurs in the distal colon (left sided).

Where would constipation potentially occur in the bowels in a patient with ulcerative colitis?

Ascending colon - this is because the descending/sigmoid colon are ulcerated and inflamed, the oedema has prevented stool passing in to this area, and subsequently the stool has collected in the ascending/transverse colon - an unusual area for collection. Expect the stool to be liquid.

What are the types of hernia?

Inguinal Femoral (- enters femoral canal) Obturator (- enters obturator canal) Umbilical (paraumbilical) Hiatus Incisional Epigastric Sciatic (- through lesser sciatic foramen) Lumbar (-through lumbar triangles on posterior abdominal wall) Spigelian (-below umbilicus at lateral edge of rectum sheath) Diaphragmatic Muscular (-muscle herniates from abdomen) Richter’s Littre’s Maydl’s

What is a Richter’s hernia?

Richter’s (- bowel wall herniates, but not the whole piece of bowel, the lumen remains in the abdomen)

What is a littre’s hernia?

Littre’s (- a strangulated meckel’s diverticulum that herniated)

What is a maydl’s hernia?

Maydl’s (- a herniated double loop of bowel, often with the strangulated loop still within the bowel)

What are the most common causes of acute abdomen?

Most common to less common: Intestinal obstruction Peritonitis secondary to infection (e.g. appendicitis) Haemorrhage (e.g. due to ectopic pregnancy or ruptured AAA) Ischemia (e.g. mesenteric ischemia, ovarian torsion) Contamination of abdominal compartment with GIT contents (e.g. perforated duodenal/gastric ulcer) ``` Another way to think of the possible causes: Obstruction Inflammation Perforation Gynaecology Vascular Infection Metabolic Toxic Urology ```

What are obstructions that cause acute abdomen?

``` Obstructions: Adhesions - incarceration of a hernia Volvulus Gallstones Intussusception - telescoping of the bowel (bowel invaginates into the adjoining bowel) GI neoplasm Congenital abnormalities IBD ```

What are the inflammatory causes of acute abdomen?

``` Inflammation: Cholecystitis Appendicitis Acute pancreatitis Acute diverticulitis Meckel diverticulitis (small intestine diverticulum) IBD ```

What are the perforations that can cause acute abdomen?

Perforation: Duodenal/gastric ulcer Oesophageal perforation Mallory-Weiss tear (tear of the mucosa at the gastro-oesophageal junction)

What are the gynaecological causes of acute abdomen?

``` Gynaecological: Ectopic pregnancy Ruptured ovarian cyst Ovarian lesion Pelvic inflammatory disease Endometriosis ```

What are the vascular causes of acute abdomen?

``` Vascular: Abdominal aortic dissection Ruptured AAA Ruptured splenic artery aneurysm Mesenteric ischemia/infarction Ischemic colitis Splenic infarct Sickle cell crises Bud-chiari syndrome (occlusion of hepatic veins) Abdominal wall haematoma (due to trauma/exercise/coughing) ```

What are the infections that cause acute abdomen?

Infection: Gastroenteritis Infectious colitis Typhilitis Of any para-GI organ (e.g. hepatic abscess) Pisa’s abscess (often due to TB from the lumbar vertebrae)

What are the metabolic causes of acute abdomen?

``` Metabolic: Uraemia (renal failure; increased toxins in serum) Diabetic ketoacidosis Addisonian crisis Hypercalcaemia Acute intermittent porphyria ```

What are the urological causes of acute abdomen?

Urological: Testicular torsion Kidney stones Pyelonephritis

What is acute appendicitis?

Lumen obstruction of the appendix by , means trapped gut bacteria invade the appendix wall, causing oedema, ischaemic necrosis and perforation. MOA of obstruction: Lymphoid hyperplasia Faecolith (faecal concretion/pellet) Filariasis worms

What are the symptoms of appendicitis?

Abdominal pain: Early - dull pain in paraumbilical region (navel) Late - becomes sharp as it moves to RIF Anorexia - loss of appetite Associated with pain: Tachycardia Fever Peritonism - guarding, and rebound/percussion tenderness in RIF Associated with anorexia: Nausea and vomiting Often apyrexial

What is Rosvig’s sign in appendicitis?

Rosvig’s sign = pain is felt in RIF when LIF is pressed

What is the psoas sign in appendicitis?

Psoas sign = pain on extending the right hip if the appendix is retrocaecal

What are the signs and symptoms of intussusception?

Redcurrant jelly stool Recital bleeding May have vomiting Colicky Abdominal pain Signs: May have abdominal mass usually in RUQ or epigastrium

What is intussusception?

A telescoping of intestine in to another portion of intestine, this drags mesentary with it, obstructing the mesentary. Oedema, mucosal bleeding and pressure occur. This causes bleeding in to the bowel and can create the redcurrant jelly stools.

Which syndrome affecting the intestines is characterised by vitamin B12 deficiency?

Imerslund-grasbeck syndrome A rare, autosomal recessive condition affecting the cubilin receptors in the ileum. So no vitamin B12 can be absorbed

Who is most at risk of C. Diff infections?

Those who are in hospital and have been on antibiotics - “clears the way” for c.dif

What is travellers diarrhoea?

Gastroenteritis (diarrhoea; production of 2+ unformed stools per day) following travel abroad

What is acute gastroenteritis?

3 or more episodes of diarrhoea per day for less than two weeks

What is persistent gastroenteritis?

More than three episodes per day for greater than two weeks

What is a c. Diff infection?

An infection of the colon with the gram positive anaerobes clostridium difficile C.diff is normally present in the gut, but becomes dominant when other flora is killed off by antibiotics Produces A and B spore forming rods, forms toxins that causes inflammatory response, and can cause pseudomembrane formation (raised yellow-white plaques in the colon on top of erythematous mucosa), which can lead to toxic megacolon, ileus or colonic perforation and peritonitis Transmission is most commonly faecal-oral Incubation time = 2-3 days Severity grades: 1. Mild - no WCC incr, less than 3 eps of loose stools 2. Moderate - WCC incr and 3-5 loose stools 3. Severe; WCC over 15 (10^9/L) Or serum creatinine 50% above baseline Or temp >38.5 Or radiological signs of severe colitis 4. Life threatening; Signs of toxic megacolon Signs of partial or complete ileus (slowing of gastric motility accompanied by distension, without mechanical obstruction - diagnosis of exclusion after obstruction is rules out)

What is toxic megacolon?

Toxic colitis with dilated colon Signs include abdo pain, distension, hypotension, increased heart rate, fever and chills

What is campylobacter?

Most common cause of gastroenteritis in the uk Comes from poultry, cattle and domestic animals Incubation:1-7 days Transmission - faecal oral Can cause toxic megacolon If severe - give macrolides

What is ETEC?

Enterotoxigenic e coli Causes a very watery diarrhoea (like cholera), with cramps and nausea Incubation = 12-72 hours Transmission: oral

What is EHEC?

Enterohaemorrhagic E. coli - E. coli H7O157 From beef and other foods Does NOT cause fever Incubation: 12-60 hours

What is salmonella enteriditus and typhimurium?

A pair of types of salmonella From raw eggs, lizards and other foods Can cause dysentery Causes pyrexia

What is enteric fever?

Type of gastroenteritis caused by Salmonella typhi and paratyphi types From water and food, Carried by humans. Does not cause dysentery Can cause meningioencephalitis or osteomyelitis

What is shigella?

A bacterial type of dysentery Transmission - faecal oral, from human carriers Incubation - 1-8 days Can cause toxic megacolon

What is amoebiasis?

Type of gastroenteritis parasitic infection causing cysts throughout the body (abscesses in the liver etc) Causes dysentery

What is schistomiasis?

A type of parasitic gastroenteritis organism. Lots of different types. There is a reaction from the immune system causing granuloma formation due to the schistosome eggs, causing severe active colitis. Need to kill adult worms AND the eggs