General - small bowel disease

Question 1

Hernia

Answer 1

Defined as the protrusion of part/whole of an organ or tissue through the wall of the cavity that normally contains it

Question 2

Epigastric hernia

Answer 2

Occurs in the upper midline through the fibres of the linea alba
Typically secondary to raised chronic intra-abdominal pressure eg. obesity, pregnancy/ascites
Relatively common, mostly affecting middle-aged men
Typically asymptomatic, but may present as a midline mass that disappear when lying on the back

Question 3

Paraumbilical hernia

Answer 3

Herniation through the linea alba around the umbilical region
Typically secondary to raised chronic intra-abdominal pressure & present as a lump around the umbilical region
Generally they contain pre-peritoneal fat although they can occasionally contain bowel

Question 4

Spigelian hernia

Answer 4

Rare form of abdominal hernia that occurs at the semilunar line (the tendinous lateral border of the rectus) around the level of the arcuate line
Clinically, they present as a small tender mass at the lower lateral edge of the rectus abdominus
High risk of strangulation and so should be repaired urgently

Question 5

Obturator hernia

Answer 5

Hernia of the pelvic floor, occurring through the obturator foramen, into the obturator canal
More common in women, typically in elderly patients
Classically present with a mass in the upper medial thigh & patient will often have features of small bowel obstruction
~50% of cases – compression of the obturator nerve = positive Howship-Romberg sign (hip and knee pain exacerbated by thigh extension, medial rotation and abduction)

Question 6

Littre’s hernia

Answer 6

Herniation of a Meckel’s diverticulum
Most commonly occurs in the inguinal canal and many will become strangulated

Question 7

Lumbar hernia

Answer 7

Rare posterior hernias, that typically occur spontaneously/iatrogenically following surgery
Present as a posterior mass, often with associated back pain

Question 8

Richter’s hernia

Answer 8

Can occur at any other sites and is a partial herniation of bowel, whereby the anti-mesenteric border becomes strangulated -> only part of the lumen of the bowel is within the hernial sac
Patients will present with a tender irreducible mass at the herniating orifice and have varying levels of obstruction (often surgical emergencies)

Question 9

Angiodysplasia

Answer 9

Most common vascular abnormality of the GI tract
Caused by the formation of arteriovenous malformations between previously healthy blood vessels
Most commonly in the caecum and ascending colon

Question 10

Angiodysplasia pathophysiology

Answer 10

1) Acquired – begins as reduced submucosal venous drainage in the colon due to chronic and intermittent contraction of the colon, giving rise to dilated and tortuous veins, results in the loss of pre-capillary sphincter competency -> causes the formation of small arterio-venous communications
2) Congenital

Question 11

Angiodysplasia clinical features

Answer 11

Asymptomatic
Painless occult PR bleeding
Acute haemorrhage
Degree of symptoms will depend upon the location and severity of the malformation (upper GI = haematemesis or melena, lower GI = more likely to present as haematochezia)

Question 12

Angiodysplasia investigations

Answer 12

Lab tests – blood tests, group and save/crossmatch
Imaging – upper GI endoscopy and/or colonoscopy depending on the suspected site of bleeding
Wireless capsule endoscopy for small bowel bleeds
Overt angiodysplastic bleed – mesenteric angiography may be required to confirm the location of a lesion in order to plan for intervention as necessary

Question 13

Angiodysplasia management

Answer 13

Patients admitted with angiodysplasia can be treated conservatively – bed-rest, IV fluid support, potential tranexamic acid
Persistent/severe cases:
1) Endoscopy – argon plasma coagulation
2) Mesenteric angiography – used for small bowel lesions that cannot be treated endoscopically
Surgical management – resection and anastomosis of the affected segment of bowel is necessary

Question 14

Angiodysplasia complications

Answer 14

Mainly related to treatment – re-bleeding post therapy is common
Endoscopic techniques – bowel perforation
Mesenteric angiography – haematoma formation, arterial dissection, thrombosis & bowel ischaemia

Question 15

Femoral hernia

Answer 15

Abdominal viscera/omentum passes through the femoral ring and into the potential space of the femoral canal
More common in women than men

Question 16

Femoral hernia risk factors

Answer 16

Female
Pregnancy
Raised intra-abdominal pressure
Increasing age

Question 17

Femoral hernia clinical features

Answer 17

Small lump in the groin
30% of femoral hernia cases will present as an emergency – obstruction/strangulation
Important to identify the exact location of the lump in the groin
- Femoral hernia: found infero-lateral to the pubic tubercle
- Inguinal hernia: found supero-medial to the pubic tubercle

Question 18

Femoral hernia investigations

Answer 18

Radiological – ultrasound scanning, CT abdomen-pelvis

Question 19

Femoral hernia management

Answer 19

Should be managed surgically, ideally within 2 weeks of presentation due to the high risk of strangulation
Two different approaches:
- Low approach: incision is made below the inguinal ligament
- High approach: incision is made above the inguinal ligament, preferred in an emergency
Operation involves reducing the hernia and then narrowing the femoral ring

Question 20

Femoral hernia complications

Answer 20

Risk of strangulation
Obstruction

Question 21

Gastroenteritis

Answer 21

Inflammation of the GI tract, usually considered infective in origin

Question 22

Gastroenteritis risk factors

Answer 22

Poor food preparation
Immunocompromised
Poor personal hygiene

Question 23

Gastroenteritis clinical features

Answer 23

Cramp-like abdominal pain
Diarrhoea
May be associated vomiting, night sweats & weight loss reported
Features from the history – bowel movements, affected family/friends, recent travel abroad, recent use of antibiotics within the previous four weeks

Question 24

Gastroenteritis investigations

Answer 24

Not necessary for most cases, as the condition is usually self-limiting
Stool culture is often warranted, esp in cases with blood/mucus, patient is immunocompromised, severe/persistent

Question 25

Gastroenteritis management

Answer 25

Rehydration, encouraging oral fluid intake where possible Education to prevent future episodes Exclusion from work is usually 48 hours

Question 26

Gastroenteritis viruses

Answer 26

Norovirus – most common form of viral gastroenteritis in adults Rotavirus – severe diarrhoea among infants and young children Adenovirus – common cause of diarrhoea in children

Question 27

Gastroenteritis bacteria

Answer 27

Campylobacter – gram negative bacillus, most common cause of food poisoning E. Coli – gram negative bacillus, typically transmitted through contaminated foodstuffs Salmonella – gram negative flagellated bacillus, transmitted through undercooked poultry/raw eggs Shigella – gram negative bacillus, commonly acquired from contaminated dairy products and water

Question 28

Gastroenteritis bacterial toxins

Answer 28

Toxins from bacteria often cause an acute onset of diarrhoea & vomiting and symptoms tend to last less than 24 hours, common bacterial toxins can arise from: - Staphylococcus aureus: typically found in meat or dairy products - Bacillus cereus: usually found in reheated rice, rapid-onset vomiting and abdominal cramps - Clostridium perfringes: re-heating meat dishes - Vibrio cholera: acquired most commonly from contaminated water supplies

Question 29

Gastroenteritis parasites

Answer 29

More common in travellers’ diarrhoea Cryptosporidium: self-limiting watery diarrhoea and abdominal cramps Entamoeba histolytica: becomes acquired from the ingestion of food/water contaminated with faeces Giardia intestinalis: transmitted through direct contact or faeco-oral route Schistosoma: acquired through contaminated water

Question 30

Hospital-acquired gastroenteritis

Answer 30

C. difficile, a gram positive organism that can develop following the use of broad-spectrum antibiotics Produce large amounts of exotoxins A & B Severe bloody diarrhoea and has the potential to develop into toxic megacolon Investigation – stool culture and C. difficile toxin testing Treatment – IV fluid rehydration and oral metronidazole

Question 31

Non-infective causes gastroenteritis

Answer 31

Radiation colitis Inflammatory bowel disease Microscopic colitis Chronic ischaemic colitis – compromise in blood supply to the colon

Question 32

Inguinal hernia

Answer 32

Occurs when abdominal cavity contents enter into the inguinal canal Most common type of hernia

Question 33

Direct inguinal hernia

Answer 33

Bowel enters the inguinal canal ‘directly’ through a weakness in the posterior wall of the canal (Hesselbach’s triangle) Most commonly in older patients, often secondary to abdominal wall laxity/significant increase in intra-abdominal pressure

Question 34

Indirect inguinal hernia

Answer 34

Bowel enters the inguinal canal via the deep inguinal ring Arise from incomplete closure of the processus vaginalis, an outpouching of peritoneum allowing for embryonic testicular descent -> usually deemed congenital in origin

Question 35

Indirect inguinal hernia risk factors

Answer 35

Male gender Increasing age Raised intra-abdominal pressure High BMI

Question 36

Inguinal hernia clinical features

Answer 36

Lump in the groin, which will initially disappear with minimal pressure/when the patient lies down Specific features - Cough impulse - Location: inguinal hernia appear superomedial to the pubic tubercle - Reducible: lying down/with gentle pressure

Question 37

Inguinal hernia investigations

Answer 37

Hernia is typically a clinical diagnosis Ultrasound scan is recommended as first line imaging Patients with features of obstruction/strangulation – CT imaging

Question 38

Inguinal hernia management

Answer 38

Symptomatic inguinal hernia should be offered surgical intervention Surgical intervention - Hernia repairs can be performed via open repair/laparoscopic repair - Open mesh repairs are preferred for those with primary inguinal hernias - Laparoscopic approach: bilateral or recurrent inguinal hernias

Question 39

Inguinal hernia complications

Answer 39

Incarceration Strangulation Obstruction Following repair: haematoma/seroma formation, recurrence, chronic pain or damage to vas deferens/testicular vessels

Question 40

Small bowel tumours

Answer 40

Most arise from the duodenum & less commonly arise from the jejunum Small bowel neoplasms can be either benign/malignant: - Benign tumours – typically adenomas - Malignant tumours – adenocarcinomas/neuroendocrine tumours

Question 41

Small bowel tumours pathophysiology

Answer 41

Believed to arise from pre-existing adenomas through a sequential accumulation of genetic abnormalities Tumour suppressor gene p53 and the oncogene KRAS have been implicated in over 50% cases

Question 42

Small bowel tumours risk factors

Answer 42

Non-modifiable – increasing age, Crohn’s disease, coeliac disease, certain genetic conditions Modifiable – smoking, obesity, low fibre intake, high intake of red meats and alcohol excess

Question 43

Small bowel tumours clinical features

Answer 43

Initially asymptomatic Cause small bowel obstruction due to luminal narrowing, less commonly present with PR bleeding Examination – abdominal mass, cachexia, jaundice, hepatomegaly, ascites

Question 44

Small bowel tumours investigations

Answer 44

Blood tests – elevated CEA levels, elevated 5-HIAA Imaging – upper Gi endoscopy, MRI enterography Majority of patients present with features of bowel obstruction, often the diagnosis is made via CT imaging PET-CT imaging is useful is metastatic disease is suspected

Question 45

Small bowel tumours management

Answer 45

Any symptomatic benign small bowel tumour should be resected either endoscopically/through surgical resection Adjuvant chemotherapy is likely required for lymph node positive disease Chemotherapy for metastatic disease