Gastro Flashcards
What is Whipple’s Disease?
A rare, chronic multisystem condition thought to be caused by a combination of infection with the gram-positive actinobacteria, Tropheryma whippelei, alongside an abnormal response of cell-mediated immunity.
Symptoms of Whipple’s Disease?
Gastro: abdominal pain and distention, diarrhoea and steatorrea, anorexia, and weight loss
Other: generalised lymphadenopathy, arthropathy, cough, intermittent pyrexia.
As infection progresses, can get respiratory, cardiac and CNS involvement e.g cognitive function abnormalities, oculomasticatory and oculofascioskeletal myorhythmia).
What investigations should you do in Whipple’s disease?
OGD: jejunum biopsies that show PAS-positive macrophages.
PCR to identify bacterial DNA
Immunohistochemistry: antibodies against Tropheryma Whippelei.
LP: All patients should have an LP to rule out CNS involvement
Management of Whipple’s Disease?
Long-term abx e.g:
14 days of ceftriaxone or benzylpenicillin
1 year maintenance therapy with trimethoprim/ sulfamethoxazole
Prognosis of Whipple’s Disease?
Fatal without treatment.
CNS involvement and arthopathy may be irreversible.
40% relapse following initial successful response to treatment
Epidemiology and risk factor for Whipple’s?
Middle-age to older men.
Associated with HLA-B27
Aetiology of Gilbert’s Syndrome?
A mild loss of glucuronosyltransferase activit
Inheritance of Gilbert’s Syndrome?
Autosomal recessive
Features on blood tests in Gilbert’s Syndrome?
Unconjugated hyperbilirubinaemia
Clinical features of Gilbert’s?
Episodes of fasting induced by fasting or infection, usually self-limiting
What is Crigler-Najjar Syndrome?
A form of glucuronosyltransferase deficiency.
Diff types of Criggler-Najjar Syndrome?
Type I (autosomal recessive) results from the loss of both copies of the gene and causes death in early childhood if a transplant is not carried out.
Type II (predeominantly autosomal recessive but can also be autosomal dominant) is the inherited loss of one gene, which causes a much milder illness with an unconjugated hyperbilirubinaemia.
Pre-hepatic causes of jaundice?
Haemolytic anaemia
Drugs
Malaria
Gilbert’s Syndrome
Crigler-Najjar Syndrome
Hepatic causes of jaundice?
Viral infection e.g hepatitis, EBV, HIV
Alcohol
NAFLD
Autoimmune liver disorders
Metabolid causes e.g Dubin-Johnson syndrome, haemochromatosis, Wilson’s disease
Malignancy of the biliary system
Drugs
Post-hepatic causes of jaundice?
Gall stones
Extra-hepatic malignancy
Pancreatitis
Pre-hepatic phase of bilirubin metabolism?
Haemoglobin molecules are broken down in macrophages into biliverdin and then bilirubin. This mainly occurs in the spleen and liver.
Bilirubin is then released and bound to albumin and transported to the liver.
Hepatic phase of bilirubin metabolism?
Hepatocytes selectively remove unconjugated bilirubin from the blood
Within the hepatocytes, glucoronic acid is attached to the bilirubin and it becomes conjugate bilirubin.
Post-hepatic phase of bilirubin metabolism?
Conjugated bilirubin is transported through the liver –> cystic ducts –> gallbladder.
In the intestine, some bilirubin is passed into stool, the rest is converted into urobilogens via the gut flora and reabsorbed and excreted via the kidneys
Drugs causing acute hepatitis?
isoniazid, rifampicin, methyldopa, atenolol, enalapril, verapamil, nifedipine, amiodarone, ketoconazole, cytotoxics and halothane.
Drugs causing acute cholestasis?
oestrogens, ciclosporin, azathioprine, chlorpromazine, haloperidol, cimetidine, ranitidine, erythromycin, nitrofurantoin, imipramine, ibuprofen and hypoglycaemics.
Which PPI reduces anti-platelet effect of clopidogrel?
Omeprazole
Pathophysiology of primary sclerosing cholangitis?
An autoimmune-mediated disease causing progressive intrahepatc and extrahepatic bile duct inflammation, stricturing and cholestasis leading to scaring of the bile ducts and accumuation of toxins.
What proportion of patients with sc also have UC?
60-70%
Investigation of choice for PSC?
MRCP- shows strictures
