gastro Flashcards
CMV colitis flare investigation
Cytomegalovirus may be a cause of a colitis flare and should be suspected in patients with steroid refractory disease. The presence of multiple intranuclear inclusion bodies on colonic biopsy is highly indicative.
PBC
Pruritus and lethargy are the classical presenting symptoms of primary biliary cirrhosis (PBC). Patients may have associated autoimmune conditions such as thyroid disease, Raynaud’s and Addison’s diseases.
Clinical features include:
Stigmata of chronic liver disease
Excoriations due to pruritus, and
Xanthelasma.
Blood results show elevated ALP and GGT with mildly elevated transaminases. A rise in bilirubin is usually a late sign. Prothrombin time may also be elevated due to impaired synthetic function or vitamin K malabsorption. IgM will be raised. AMA autoantibodies are positive in 95% of cases.
Abdominal ultrasound must be performed in all cases to exclude biliary duct dilatation. The need for liver biopsy is debated as it rarely affects the management but it is indicated in cases of diagnostic uncertainty.
PBC increases the risk of hepatocellular carcinoma but often focal liver lesions are seen on ultrasound in cases of HCC.
grading encephalopathy
Pruritus and lethargy are the classical presenting symptoms of primary biliary cirrhosis (PBC). Patients may have associated autoimmune conditions such as thyroid disease, Raynaud’s and Addison’s diseases.
Clinical features include:
Stigmata of chronic liver disease
Excoriations due to pruritus, and
Xanthelasma.
Blood results show elevated ALP and GGT with mildly elevated transaminases. A rise in bilirubin is usually a late sign. Prothrombin time may also be elevated due to impaired synthetic function or vitamin K malabsorption. IgM will be raised. AMA autoantibodies are positive in 95% of cases.
Abdominal ultrasound must be performed in all cases to exclude biliary duct dilatation. The need for liver biopsy is debated as it rarely affects the management but it is indicated in cases of diagnostic uncertainty.
PBC increases the risk of hepatocellular carcinoma but often focal liver lesions are seen on ultrasound in cases of HCC.
small bowel bacterial overgrowth
Steatorrhoea and flatulence are classic presenting features of small bowel bacterial overgrowth.
At risk groups are those with:
absent gastric acid secretion
small bowel diverticulae
fistulae between the small and large bowel
small bowel strictures
diabetic neuropathy, and
adhesions.
Biochemically there is classically a low vitamin B12 level and normal or elevated folate level as a result of bacterial metabolism of B12 to folate.
Bile salt malabsorption
Bile salt malabsorption causes secretory diarrhoea (watery) and is a result of failure of bile salt reabsorption due to disease of the terminal ileum.
Melanosis coli
Melanosis coli is found in patients who use and abuse anthraquinone laxatives. Melanosis coli is a histological diagnosis made from rectal biopsy material which shows numerous macrophages filled with brown pigment within the lamina propria. This phenomenon is seen in over 70% of persons who use anthraquinone laxatives (for example, cascara sagrada, senna, and frangula) within several months of use.
The condition is benign and reversible on stopping the laxatives.
The macroscopic appearance varies from deep black pigmentation to reticulated brown discolouration.
Melanosis coli may involve the entire large intestine, but can be segmental.
The discolouration is caused by deposits of lipofuscin rather than true melanin deposition.
Anthraquinone cathartics induce apoptosis of epithelial cells of the large intestine. The apoptotic bodies are taken up by epithelial macrophages and they are converted to lipofuscin.
hyponatremia and DLD
The British Society of Gastroenterology guidelines suggest that where the serum sodium is ≤120 mmol/L diuretic therapy should be stopped and patients should receive volume expansion with colloid or normal saline.
These guidelines also advise that fluid restriction should only be used in patients who are clinically euvolaemic, not on diuretics and have severe hyponatraemia with a normal serum creatinine.
Bloody ascitic fluid
Bloody ascitic fluid with a Gram stain revealing Gram negative bacilli and Gram positive cocci is suggestive of bowel perforation.
Anti-mitochondiral antibodies
Anti-mitochondiral antibodies are positive in 95% of cases of primary biliary cirrhosis.
Autoimmune gastritis
Autoimmune gastritis is associated with anti-gastric parietal cell antibodies, with or without pernicious anaemia.
Anti-liver kidney microsomal antibodie
Anti-liver kidney microsomal antibodies are found in autoimmune chronic hepatitis.
coeliac antibodies
Anti-endomysial and anti-tissue transglutaminase antibodies are found in patients with coeliac disease.
Bartter’s syndrome
hypokalaemic metabolic alkalosis with urinary potassium wasting characteristic of Bartter’s syndrome.
Bartter’s syndrome usually presents in childhood with polyuria, nocturnal enuresis and growth retardation.
Bartter’s syndrome is associated with hyperplasia of the juxtaglomerular apparatus.
haemochromatosis
Clinical signs of haemochromatosis include hepatomegaly, cirrhosis and splenomegaly. Patients may have cardiomyopathy and endocrine complications including diabetes mellitus, hypogonadism, panhypopituitarism and testicular atrophy. The term ‘bronze diabetes’ comes from the skin pigmentation which is seen in these patients. Chondrocalcinosis and arthritis may also develop. Hepatocellular carcinoma should be excluded especially in those with cirrhosis with three to six monthly alpha fetoprotein and ultrasound.
wilsons disease
Wilson’s disease presents between the ages of three and 40 years. Acute hepatitis, acute liver failure and decompensated cirrhosis are all recognised with Wilson’s disease.
Neuropsychiatric features are common in adolescence and early adulthood with behavioural change, parkinsonism and cognitive impairment.
Kayser-Fleischer rings are seen in patients with neurological disease.
Primary sclerosing cholangitis
Primary sclerosing cholangitis is associated with inflammatory bowel disease. Patients often present with pruritus, intermittent jaundice and right upper quadrant pain. Features of cholangitis (fever, pain and jaundice) usually occur subsequent to instrumentation such as endoscopic retrograde cholangiopancreatography (ERCP). Examination reveals signs of chronic liver disease and signs of portal hypertension may be present.
GORD management
In endoscopically determined gastro-oesophageal reflux disease or oesophagitis full-dose proton pump inhibition for one month will typically result in healing in 76%, continuation for a further month increases this by a further 14%. In those failing to respond to two months of full dose therapy doubling the dose of proton pump inhibitor increases response rate.
In those failing to respond to a double dose of proton pump inhibition an H2 receptor antagonist may be added or substituted in treatment or a prokinetic agent added to treatment. Simply extending the duration of proton pump inhibitor therapy beyond two months without any additional change is not recommended.
Repeat gastroscopy is not recommended in the absence of new or emergent symptoms or where there is severe resistance to therapy.
It is also the latter group in whom referral for consideration of acid reflux reduction surgery might be considered.
GORD management
In endoscopically determined gastro-oesophageal reflux disease or oesophagitis full-dose proton pump inhibition for one month will typically result in healing in 76%, continuation for a further month increases this by a further 14%. In those failing to respond to two months of full dose therapy doubling the dose of proton pump inhibitor increases response rate.
In those failing to respond to a double dose of proton pump inhibition an H2 receptor antagonist may be added or substituted in treatment or a prokinetic agent added to treatment. Simply extending the duration of proton pump inhibitor therapy beyond two months without any additional change is not recommended.
Repeat gastroscopy is not recommended in the absence of new or emergent symptoms or where there is severe resistance to therapy.
It is also the latter group in whom referral for consideration of acid reflux reduction surgery might be considered.
iron deficiency investigations
The serum ferritin is the most powerful marker of iron deficiency in the absence of inflammation, should there be inflammation transferrin saturation should be used.
IBS investigations
Abdominal bloating, alternating diarrhoea and constipation, abdominal pain relieved by defecation and urgency are all classical features of irritable bowel syndrome. Adequate history must be taken to exclude red flag symptoms such as weight loss. Coeliac disease must be excluded as a possible alternative diagnosis.
NICE guidelines on the diagnosis and management of Irritable bowel syndrome (CG61) state that in the presence of a history classical for irritable bowel syndrome (and the absence of red flag symptoms such as weight loss) the following are sufficient to exclude other causes of bowel symptoms:
A normal full blood count
C-reactive protein
Erythrocyte sedimentation rate, and
Negative anti-tissue transglutaminase antibodies.
Risk factors for toxic megacolon in UC
management of ulcerative colitis identify the following as risk factors for the precipitation of toxic colonic dilatation:
Hypokalaemia Hypomagnesaemia Under-treatment Purgative bowel preparations for colonoscopy Non-steroidals Opioids Anti-cholinergics, and Anti-diarrhoeal agents.
gastric vs duodenal ulcer
Patients with gastric ulceration tend to suffer from anorexia and weight loss while those with a duodenal ulcer maintain or gain weight.
Although weight gain may be suggestive of duodenal ulceration the characteristic clinical feature which aids the diagnosis is abdominal pain which is relieved by eating. Endoscopy should be performed to confirm ulceration.
Risk factors for peptic ulceration include Helicobacter pylori (H. pylori) infection, non-steroidal anti-inflammatory drug (NSAID) use, cigarette smoking and genetic factors - Lewis blood group antigens facilitate H. pylori attachment to the mucosa.
medication that cause dyspepsia
The following drugs are recognised as causing dyspepsia:
Steroids Calcium channel blockers Theophyllines Nitrates Bisphosphonates, and Non-steroidal anti-inflammatory drugs. This is either due to irritation of the mucosa (for example, bisphosphonates, steroids) or relaxation of the lower oesophageal sphincter increasing reflux (for example, calcium channel blockers, nitrates).
