Gastroenterology and Hepatology Lecture Review

Vocabulary flashcards covering functional anatomy, physiology, and specific diseases in gastroenterology and hepatology from the lecture text.

Dysphagia

Defined as difficulty in swallowing.

Odynophagia

Pain during swallowing, usually from gastro-oesophageal reflux or candidiasis.

Globus sensation

A sensation in which anxious people feel a lump in the throat without organic cause.

Dyspepsia

Symptoms such as discomfort, bloating and nausea, which are thought to originate from the upper gastrointestinal tract.

Heartburn

Retrosternal, burning discomfort, often rising up into the chest and sometimes accompanied by regurgitation of acidic or bitter fluid into the throat.

Haematemesis

Vomiting of blood, which appears red with clots when bleeding is rapid or black ('coffee grounds') when less severe.

Melaena

The passage of black, tarry stools containing altered blood, usually caused by bleeding from the upper gastrointestinal tract.

Diarrhoea

Defined as the passage of more than $200\,g$ of stool daily.

Steatorrhoea

Bulky, pale and offensive stools that float in the toilet, signifying fat malabsorption.

Constipation

Defined as the infrequent passage of hard stools.

Oesophagus

A muscular tube that extends $25\,cm$ from the cricoid cartilage to the cardiac orifice of the stomach.

Parietal cells

Gastric cells that secrete hydrogen and chloride ions into the lumen to form hydrochloric acid and produce intrinsic factor.

Gastrin

A hormone produced by G cells in the antrum that stimulates acid secretion and mucosal growth.

Somatostatin

A hormone secreted from D cells throughout the stomach that inhibits gastrin and insulin secretion and decreases acid secretion.

Enterokinase

A brush border enzyme that converts inert trypsinogen to the active proteolytic enzyme trypsin.

Intestinal microbiota

The microorganisms that live in a particular niche within the human body, numbering approximately $10^{14}$ residents.

Interstitial cells of Cajal

Stellate cells of mesenchymal origin that act as the 'pacemaker' of the gut.

Migrating motor complexes (MMCs)

Waves of contraction spreading from the stomach to the ileum every $90\,minutes$ or so between meals and during fasting.

Gastrocolic reflex

A reflex stimulated after meals involved in the propulsion of faeces to the rectum, mediated by hormones like $5\text{-hydroxytryptamine}$, motilin and CCK.

Blatchford score

A risk scoring system used before endoscopy to predict the need for intervention in patients with acute upper gastrointestinal haemorr hage.

Barrett’s oesophagus

A pre-malignant condition in which the normal squamous lining of the lower oesophagus is replaced by columnar mucosa.

Achalasia

An oesophageal motility disorder characterized by a hypertonic lower oesophageal sphincter and failure of propagated oesophageal contraction.

Boerhaave’s syndrome

Spontaneous oesophageal perforation resulting from forceful vomiting and retching.

Gastritis

A histological diagnosis of gastric inflammation, often erosive and haemorrhagic when acute.

Zollinger–Ellison syndrome

A rare disorder characterized by severe peptic ulceration, gastric acid hypersecretion and a gastrin-secreting neuro-endocrine tumour.

Gastroparesis

Defective gastric emptying without mechanical obstruction of the stomach or duodenum.

Coeliac disease

An inflammatory disorder of the small bowel resulting from intolerance to wheat gluten in genetically susceptible individuals.

Tropical sprue

Chronic, progressive malabsorption occurring mainly in the West Indies, southern India, Malaysia and Indonesia, often starting after an acute diarrhoeal illness.

Whipple’s disease

A rare multisystem disease caused by infection with the Gram-positive bacillus Tropheryma whipplei.

Crohn’s disease

A chronic inflammatory bowel disease characterized by transmural inflammation, skip lesions and deep fissuring ulcers ('cobblestone' appearance).

Ulcerative colitis

A chronic inflammatory bowel disease involving only the colon, where inflammation is limited to the mucosa and spread is continuous from the rectum.

Toxic megacolon

A life-threatening complication of colitis where the transverse colon dilates to more than $6\,cm$, risking perforation.

Irritable bowel syndrome (IBS)

A clinical diagnosis based on recurrent abdominal pain or discomfort on at least $3\,days$ per month in the last $3\,months$, associated with abnormal defecation.

Familial adenomatous polyposis (FAP)

An autosomal dominant disorder resulting from germline mutation of the APC gene, leading to hundreds or thousands of adenomatous colonic polyps.

Peutz–Jeghers syndrome

An autosomal dominant disorder characterized by multiple hamartomatous polyps and melanin pigmentation of the lips, mouth and digits.

Hereditary non-polyposis colon cancer (HNPCC)

Also known as Lynch syndrome, an autosomal dominant condition caused by germline mutations in DNA mismatch repair genes.

Hirschsprung’s disease

Constipation and colonic dilatation due to congenital absence of ganglion cells in a segment of the large intestine.

Ogilvie’s syndrome

Acute colonic pseudo-obstruction characterized by massive enlargement of the proximal colon without mechanical obstruction.

Stellate cells (Ito cells)

Liver cells located in the space of Disse that store vitamin A and play a key role in producing fibrous tissue during liver injury.

Prothrombin time (PT)

A measure of the time taken for blood to clot; it is one of the most important biomarkers of hepatocyte synthetic function.

Jaundice

Yellowish discoloration of skin and sclera detectable when plasma bilirubin exceeds $40\,\mu mol/L$ ($\cong 2.5\,mg/dL$).

Serum–ascites albumin gradient (SAAG)

A gradient calculated by subtracting ascites albumin from serum albumin; a value of $> 11\,g/L$ ($1.1\,g/dL$) is predictive of portal hypertension.

Spontaneous bacterial peritonitis (SBP)

Infection of ascitic fluid indicated by an ascites neutrophil count of $> 250 \times 10^{6}/L$.

Hepatic encephalopathy

A neuropsychiatric syndrome caused by liver disease, characterized by features such as flapping tremor, constructional apraxia and slurred speech.

Cirrhosis

A condition characterized by diffuse hepatic fibrosis and nodule formation.

Portal hypertension

A condition defined clinically by a hepatic venous pressure gradient exceeding $10\,mmHg$.

Transjugular intrahepatic portosystemic stent shunt (TIPSS)

A procedure using a stent placed between the portal vein and hepatic vein to reduce portal pressure.

Primary biliary cholangitis (PBC)

A chronic cholestatic liver disease predominantly affecting women, characterized by antimitochondrial antibodies (AMA) and damage to small bile ducts.

Primary sclerosing cholangitis (PSC)

A cholestatic liver disease caused by diffuse inflammation and fibrosis leading to obliteration of the entire biliary tree, often associated with ulcerative colitis.

Hepatocellular carcinoma (HCC)

The most common primary liver tumour, for which cirrhosis is present in $75\text{--}90\%$ of cases.

Gilbert’s syndrome

The most common inherited disorder of bilirubin metabolism, causing mild unconjugated hyperbilirubinaemia especially with fasting.

Haemochromatosis

A condition resulting in increased total body iron deposited in organs; hereditary forms are most commonly due to the C282Y mutation in the HFE protein.

Wilson’s disease

An autosomal recessive disorder of copper metabolism caused by mutations in the ATP7B gene, leading to copper deposition in the liver, brain and eyes.

Budd–Chiari syndrome

An uncommon condition caused by thrombosis of the larger hepatic veins and sometimes the inferior vena cava.

Charcot’s triad

The clinical presentation of jaundice, right upper quadrant pain and fever, indicative of acute cholangitis.

Grey Turner’s sign

Discoloration of the flanks, a feature of severe pancreatitis with haemorrhage.

Cullen’s sign

Discoloration of the periumbilical region, a feature of severe pancreatitis with haemorrhage.

Kayser–Fleischer rings

Greenish-brown discoloration of the corneal margin caused by copper deposition in Wilson's disease.