Gastroenterology Flashcards
Which antibiotic is most strongly associated with Clostridium difficile infections?
Clindamycin
What is ranitidine?
H2 receptor antagonist
What is the MELD score?
The Model for End-stage Liver Disease (MELD) score
A cirrhosis severity scoring system that predicts three-month survival
What is the Child-Pugh score?
A method of determining prognosis in liver disease, particularly cirrhosis
Which clinical features suggest decompensation of cirrhosis?
Jaundice
Ascites
Variceal haemorrhage
Hepatic encephalopathy
What causes ascites in liver disease?
Portal hypertension rather than hypoalbuminemia
Why do patients with liver disease have hypoalbuminemia?
The liver produces albumin
How is hepatic encephalopathy treated?
Lactulose
How does lactulose work in hepatic encephalopathy?
lactulose is converted to lactic acid by intestinal flora → acidification in the gut leads to conversion of ammonia (NH3) to ammonium (NH4+) → ammonium is excreted in the faeces → decreased blood ammonia concentration
What is the function of bile?
Absorption of fat and fat-soluble vitamins
What is Reynold’s pentad?
Ascending cholangitis
- RUQ pain
- Jaundice
- Fever
- Shock (low BP, tachycardia)
- Altered mental status
What is the most common benign tumour of the kidney?
Angiomyolipoma
What is a Sister Mary Joseph nodule?
Palpable nodule bulging into the umbilicus as a result of metastasis of malignant cancer in the pelvis or abdomen
What is emphysematous cholecystitis?
Infection of the gallbladder with gas-forming bacteria
Air is found in the gallbladder wall or lumen
What is the most common renal malignancy in adults?
Renal cell carcinoma
What is the triad of renal cell carcinoma?
- Haematuria (most common)
- Flank pain
- Palpable flank pass
Only 5-10% of patients present with all three components of the triad
What is the major complication of rapid paracentesis?
Paracentesis-induced circulatory shock
Fast reaccumulation of ascites
Hyponatremia
Renal impairment
Impaired survival
How does alpha-1-antitrypsin deficiency affect the liver?
Impaired secretion of alpha-1-antitrypsin by hepatocytes → intracellular accumulation of alpha-1-antitrypsin → hepatocyte destruction → hepatitis and liver cirrhosis
Which two antibiotics can be used for C. diff infection?
Metronidazole
Vancomycin (severe disease)
Only time when oral vanc is used. Vanc is not absorbed by the GI but stays in the large bowel where it can kill C diff
Which biomarkers can be used to diagnose and monitor IBD?
Faecal calprotectin and lactoferrin
What is cholelithiasis?
Gallstones
What is cholecystitis?
Inflammation of the gallbladder
What is cholangitis?
Infection of the biliary tree
What are the risk factors for cholelithiasis?
Fat, Female, Fertile (multiple children or pregnant), Forty (or older), Fair-skinned, Family history
6 F’s
What is charcot’s triad for cholangitis?
- Abdominal pain
- High fever
- Jaundice
What is the most common cause of Budd-Chiari syndrome?
Polycythemia vera
What is Budd-Chiari syndrome?
Hepatic venous obstruction → hepatomegaly, ascites, abdominal discomfort
What is the most important risk factor for AAAs?
Smoking
Also advancing age, atherosclerosis, hypercholesterolaemia, hypertension
Where is splenic pain referred to?
Left shoulder
What is McBurney’s sign?
Point tenderness in the area one-third of the distance from the right anterior superior iliac spine to the umbilicus
Suggests appendicitis
What is Rovsing’s sign
Deep palpation of the LLQ causes RLQ pain
Appendicitis
What is the psoas sign?
RLQ pain with extension of the right leg against resistance
Appendicitis
What is the obturator sign?
RLQ pain with flexion and internal rotation of the right leg
Appendicitis
Name 3 of the most common organisms found in abdominal sepsis from the stomach or duodenum
1. Streptococcus
- Candida
- Lactobacilli
- Fungi
* Aerobic species predominate*
Name 3 of the most common organisms found in abdominal sepsis from the bowel and appendix
1. E. coli
2. Bacteroides fragilis
- Clostridium
- Peptostreptococcus
- E. faecalis
Anaerobes predominate
Which 3 organisms are most commonly responsible for cholecystitis?
- E. coli
- Klebsiella
- Enterococcus
Bowel ischaemia dramatically increases the risk of sepsis from which organism?
Clostridium
What do Cullen’s and Grey Turner’s signs suggest?
Retroperitoneal bleeding
Non-specific and sensitive sign of haemorrhagic pancreatitis, but associated with a poor prognosis
Also ruptured or leaking AAA
An increased proportion of immature neutrophils in the blood is known as a right or left shift?
Left shift
What type of nociceptors are most commonly involved in visceral pain and what stimulates them?
Mechanoreceptors
Stimulated by stretch
What type of nociceptors are most commonly involved in somatic pain and what stimulates them?
Chemoreceptors
Stimulated by blood or inflammatory cytokines
What electrolyte abnormality is found in pancreatitis?
Hypocalcaemia
Lipase breaks down peripancreatic and mesenteric fat → release of free fatty acids that bind calcium →hypocalcaemia
What is the most common cause of acute pancreatitis?
Gallstone
Distal to the ampulla of Vater, impeding the flow of pancreatic secretions
Which organs are retroperitoneal?
SAD PUCKER
S: suprarenal (adrenal) gland
A: aorta/IVC
D: duodenum (second and third part)
P: pancreas (except tail)
U: ureters
C: colon (ascending and descending)
K: kidneys
E: (o)esophagus
R: rectum