CLINICAL INFECTIONS: GASTROINTESTINAL

Question 1

Sterile sites

Answer 1

Peritoneal space, pancreas, gall bladder, liver

Question 2

non-sterile sites

Answer 2

Mouth, oesophagus, stomach, small bowel, large bowel

Question 3

Angular chelitis

Answer 3

Acute/chronic inflamamtion of the skin located at the lateral commisures of the mouth. caused by candida/staph aures travelling from within the mouth to outside where theres been excessive exposure to saliva. People more at risk with dentures.
Symptoms: erythema, maceration (breaking down of skin due to moisture), scaling, lesions often bilateral.
Treat with antifungals/antibiotics.

Question 4

Bacterial overgrowth

Bacterial translocation

Answer 4

1) In small bowel –>associated with malabsorption / chronic dioarrhoea. may result from low production of HCL, surgery or radiation damage.
2) Defined as passage of viable bacteria from the gastrointestinal (GI) tract to extraintestinal sites, such as the mesenteric lymph node complex (MLN), liver, spleen, kidney, and bloodstream.
May be Cholestatic pattern of liver test abnormalities. murphys sign positive,

Question 5

Biliary tract infection

Answer 5

Inflammation of vessels in the biliary tree.
Symptoms: fever, abdo pain, jaundice and cholangitis. Pain 1 hour after eating fatty foods. Murphys sign.
Abnormal LFT’s caused by blockages –> enables bacteria to grow in the stagnation.

Question 6

Complicated abdominal infection

Answer 6

Defined as an infection that extends beyond the hollow viscus of origin into the peritoneal space. is associated with either abscess formation or peritonitis.

Question 7

Dental infections

Answer 7

• Dental alveolar infection –> swelling and acute pain.
  Acid produced by bacteria (strep mutans and lactobacillus spp) erodes the enamel and bone. bacteria moves inside tooth and causes inflammation
  Diagnosis: X-ray and examination: Areas of translucency show erosion.
  Peridontal infection: plaque beneath the gingival margin e.g peridontitis–> needs antibiotics!

Question 8

Deep neck space infections

Answer 8

rapid onset and can progress to life-threatening conditions.
Symtoms: painful swallowing, unilateral sore throat, ear ache. Signs: lock jaw, unilateral deviation of uvula to unaffected side.
Unilateral swellings of the tonsil. normally caused by strep pyogenes.

Question 9

Gastroeneritis

Answer 9

Dystentry: blood in faeces, diarrhoea (3 or more loose stools per day. Acute is under 14 days infection. Caused by pre-formed toxins eg staphylococcal toxin.
Diagnosis based on bristol stool chart.
Treat with oral rehydration.

Question 10

H.pylori infection

Answer 10

Can produce ammonia which neutralises PH and enables h.pylori to grow.
Symptoms: stomach pain and ulcers
10-15% patients with h.pylori develop stomach ulcers.
Diagnosis: urease breath test, serology.
Treat with antibiotics and PPIs.

Question 11

Hepatosplenic candidiasis

Answer 11

Seen in patients with haematological malignancies who are recovering from neutropenia e.g. post chemo so body begins to react to candida present.
Symptoms: liver pain, abdo pain, raised LFT’S, lesions of candida.

Question 12

Mucositis

Answer 12

Inflammation of the mucous membranes of the GI tract.

Occurs 2 weeks after stopping chemo

Question 13

Oral Hairy Leucoplakia

Answer 13

common in patients with AIDS. Develop flat white plains onthe tongue caused by epstein barr virus.
Treat with anti-retrovirals.

Question 14

Oral herpes

Answer 14

90% of people get herpes once and 10% get symptoms

Question 15

Oral candidiasis

Answer 15

Pseudomembranous form = most common and appears as white plaques on the buccal mucosa, tongue or oropharynx.
many are aysmptomatic, but some have pain on eating.

Question 16

Oesophageal candidiasis

Answer 16

Pain on swallowing. Patients usually localise pain to a retrosternal area.
Most common in HIV affected patients. AIDS defining illness.

Question 17

Liver abscess

Answer 17

Obstruction from billiary tree = commonest cause. e.g. portal vein obstruction following peritonitis or colonic perforation.
Diagnosed: serum alkaline phosphatase elevated usually. Imaging used.

Question 18

TB

Answer 18

Symptoms: local eg non healing oral ulcers, gastric ulcers giving gastric outflow obstruction, enterocutaneous fistulas.
Diagnosis: upper GI endoscopy with biopsies of small intestine = diagnostic test of choice and PCR for the organism.

Question 19

Whipples disease

Answer 19

Caused by Tropheryma Whipplei = bacterium detected in sewerage.
Symptoms: joint issues, chronic diarrhoea, malabsorption and weight loss.
GI symptoms that you’d associate with other things, usually investigated last of all.

Question 20

Antibiotic associated diarrhoea

Answer 20

Occurs in 5-30% patients during/ up to 2 months after antibiotic treatment. Due to disruption of gut micobiota. Change in metabolism (carbohydrates/bile acids)

Question 21

Appendicitis

Answer 21

Complicated: needs surgical management plus antibiotics
Uncomplicated: surgical management plus single dose of antibiotic prophylaxis.
Difficult to diagnose and CT’s miss 10%.

Question 22

Uncomplicated diverticulitis

Answer 22

No need for antibiotics, however it is used in treating complicated cases alongside draining abscesses.

Question 23

Complicated abdominal infection

Answer 23

One that extends past the souce organ.

Question 24

Pancreatits

Answer 24

Anribiotics should be withheld until infection is proven with positive cultures,

Question 25

Oesophageal rupture

Answer 25

Boerhaave syndrome is a spontaneous perforation of the esophagus that results from a suddenincrease in intraesophageal pressure combined with negative intrathoracic pressure. Rupture in the intrathroacic eosophagus results in contamination of the mediastinal cavity with gastric contents –> Chemical mediastinitis.
Management: avoid oral intake. Need nutritional support, typically paraenteral, IV PPI’s, antibiotics and drainage of fluid from necrotic tissue.