Day: March 13, 2024

Overview Eosinophilic oesophagitis is a chronic immune-mediated disease, characterised by eosinophil-predominant inflammation. Eosinophilic oesophagitis (EO or EoE if American spelling) is an increasingly recognised oesophageal disorder. It is a chronic immune-mediated oesophageal disorder that is characterised clinically by symptoms of oesophageal dysfunction and histologically by an eosinophil-predominant inflammatory response. EO usually occurs in the third and fourth decades of life and most commonly affects men with some genetic elements identified. Aetiology Eosinophilic oesophagitis is an allergy-driven disease. Like most allergy-driven diseases, the causes of EO is incompletely understood but related to genetic, environmental and host immune factors. There is a strong association

Definition & classification Crohn’s disease is a chronic inflammatory disorder, which can affect any part of the gastrointestinal tract from mouth to anus. Inflammatory bowel disease Inflammatory bowel disease (IBD) is an umbrella term for two chronic inflammatory disorders of the gastrointestinal system: Ulcerative colitis (UC) Crohn’s disease (CD) Though related, the two conditions have different pathologies, presentations and treatments. Whilst UC is a continuous inflammation of the mucosa starting in the rectum (in most cases) and limited to the colon, in CD transmural patchy inflammation is seen throughout the gastrointestinal tract. Crohns disease Crohns disease is a form of inflammatory bowel disease characterised

Overview Constipation is a common complaint that refers to the infrequent passage of stool, difficulty passing stool, and/or a sensation of incomplete emptying. Constipation refers to passing infrequent and/or hard stools, difficulty passing stools (e.g. straining), and/or the feeling of incomplete emptying. It is an extremely common complaint that can occur at any age. It is important to remember that the term is very broad and refers to different difficulties in defaecation. In general, constipation may occur acutely and resolve or become a chronic problem. Acute constipation is commonly due to medications (e.g. opioids). Chronic describes constipation that has been present for ≥ 3 months

Definition & classification Coeliac disease is a systemic autoimmune condition triggered by dietary gluten peptides. Coeliac disease is common among northern Europeans. Within the UK, the estimated prevalence is 1%. It is considered to be twice as common in females as in males. The condition may present at any age; however a growing proportion of patients are diagnosed in older age. The presentation is varied, ranging from diarrhoea and bloating, to iron-deficiency anaemia or osteoporosis. Aetiology Coeliac disease develops due to intolerance to proteins called ‘prolamins’. Gluten is a general term for the proteins found within wheat and other cereal grains. It is a complex mixture of

Overview Barrett’s oesophagus refers to columnar metaplasia of the distal oesophagus. Barrett’s oesophagus (BO) is defined as any portion of the normal distal oesophageal squamous epithelial lining being replaced by metaplastic columnar epithelium. Metaplasia refers to the transformation one mature cell type into another. This metaplastic change is the consequence of persistent oesophageal injury due to chronic reflux of stomach content. The condition is important because it can predispose to the development of oesophageal adenocarcinoma with a 0.33% annual risk in patients with BO without dysplasia (i.e. abnormal cells). Epidemiology Barrett’s oesophagus is a prevalent condition. BO is estimated to occur in 5-15% of patients undergoing upper

Overview Lower gastrointestinal bleeding (LGIB) classically refers to bleeding that occurs distal to the ligament of Treitz. The ligament of Treitz (suspensory ligament of the duodenum) marks the boundary between the upper and lower gastrointestinal (GI) tracts. It arises from the right crus of the diaphragm and suspends the duodenojejunal flexure. LGIB may be acute or chronic: Acute LGIB: presents with PR bleeding or altered blood with or without signs of shock. This note will focus on acute LGIBs. Chronic LGIB: typically asymptomatic and picked up incidentally following blood tests indicating iron deficiency anaemia. Signs or biochemistry of chronic LGIB are indications

Overview Achalasia is a rare motility disorder that affects the oesophagus. Achalasia is a primary motility disorder of the oesophagus that is characterised by failure to relax of the lower oesophageal sphincter. The cardinal symptom of achalasia is dysphagia (difficulty swallowing), which is typically to both solids and liquids. Symptoms are usually slowly progressive and it may be months or years before a patient seeks medical attention. Epidemiology Achalasia is a rare disorder. The global prevalence of achalasia is estimated at 1.8-12.6 per 100,000 persons per year. The peak onset is between 30-60 years of age and there is no sex predilection. Aetiology & pathophysiology

Overview This is a four-part series covering gastrointestinal physiology. Part I – Overview of the gastrointestinal system & the oral cavity. Part II – Digestion: stomach & control of digestion. Part III – Secretion: pancreas & hepatobiliary system. Part IV – Absorption: small intestine. The small intestine is the main site of absorption within the gastrointestinal tract. It is approximately 3-6m in length, extending from the pylorus of the stomach to the ileocaecal valve, and is divided into the: Duodenum: runs from the pylorus of the stomach to duodenojejunal junction in a C-shape. It is the shortest part of the small intestine, typically 25cm in length.

Overview This is a four-part series covering gastrointestinal physiology. Part I – Overview of the gastrointestinal system & the oral cavity. Part II – Digestion: stomach & control of digestion. Part III – Secretion: pancreas & hepatobiliary system. Part IV – Absorption: small intestines. In part III we look at the secretions of the hepatobiliary system and the exocrine pancreas. Their secretions, released into the small intestines are essential to the normal digestion and absorption of nutrients: Hepatobiliary system: this consists of the liver, gallbladder and bile ducts. Bile is secreted by hepatocytes into the biliary circulation. It is stored in the bile duct and released

Overview This is a four-part series covering gastrointestinal physiology. Part I – Overview of the gastrointestinal system & the oral cavity. Part II – Digestion: stomach & control of digestion. Part III – Secretion: pancreas & hepatobiliary system. Part IV – Absorption: small intestines. In part II we will take a look at the stomach and its role in digestion. The stomach is a highly specialised organ whose epithelium secretes hydrochloric acid and digestive enzymes. Its capacity reaches around 1-1.5L in adults. It receives food from the oesphagus and mixes it with gastric secretions, aiding digestion and forming chyme (acidic semi-liquid partially digested material). Chyme is

Overview This is a four-part series covering gastrointestinal physiology. Part I – Overview of the gastrointestinal system & the oral cavity. Part II – Digestion: stomach & control of digestion. Part III – Secretion: pancreas & hepatobiliary system. Part IV – Absorption: small intestines. The gastrointestinal (GI) system can be divided into the digestive tract & accessory organs. Digestive tract The digestive tract is a continuous tube that runs from mouth to anus. The lumen of the digestive tract is continuous with the external environment and is therefore not sterile. The digestive tract is approximately 9m in length in its uncontracted state (4.5m in contracted state). It is divided into different