Flashcards in Review of posters 13/05/2016 Deck (74):
Primary biliary cholangitis (cirrhosis)
Autoimmune disorder where the T cells attack the cells lining the bile duct.
Pathology of PBC
T cells attack the cells lining the bile duct. They become damaged and start to leak out bile into the interstitial space. This bile eventually gets into the bloodstream.
Why does the immune system only target bile duct cells?
Patients with autoimmune PBC have high levels of anti-microbial antibodies (antibodies that attack the mitochondria) which are specific to bile ductule cells.
Symptoms and clinical signs of PBC
Pruiritis (itchy skin)
What will blood tests show?
Raised ALP and GGT. Probably raised serum bilirubin in later stages of disease.
Treatment of PBC
What organism causes TB?
How does TB spread?
Via airborne droplets
Pathology of TB
Droplets inhaled- get into the lungs. Alveolar macrophages then ingest them. Inside the alveolar macrophages the bacilli proliferate and cause them to release neutrophil attracting chemokines and cytokines. This causes an inflammatory response and granulomas form. In the middle of the granuloma is a caseous necrotic centre.
Describe the differences in findings between latent TB and primary TB.
Latent TB- bacilli present in ghon focus
Primary TB- bacilli present in lung tissues and secretions aswell as in the ghon focus
Latent TB- non infectious
Primary TB- highly infectious
Latent TB- no symptoms
Primary TB- symptoms
Latent TB- Sputum smear and culture negative
Primary TB- sputum smear and culture positive
Latent TB- CXR normal
Primary TB- CXR showing consolidation and effusi
Symptoms of TB
Tiredness and fatigue
What is latent TB?
Generally- people who develop TB are immunocompromised in some way which allows it to take over. However if TB infects a normal individual the body will form an immune response against it and will remember it.
Treatment of TB
2 months of:
Rifampicin- yellow body fluids
Isoniazid- yellow skin
Ethambutol - blurred vision
Pyraxinamide - gout exacerbation
4 months of
Tests for TB
Ziehl Neelson test- stains bacilli yellow orange
Culture- 6 weeks
Smear and sputum sample
Define a hernia
An abnormal protrusion of a viscera out with its normal body cavity
Name hernias coming from natural openings
Inguinal, femoral, umbilical, splegian, obtrurator, oesophageal hiatus
Name hernias coming from weak areas
Incisional, epigastric, paraumbilical, parastornal
Predisposing factors to hernias
Obesity, heavy lifting, pregnancy, physical debility
Hernia coming out of the umbilical region
Congenital defect- weakness
Usually resolves by the time they are 3, if not surgically remove
Arise from congenital weakness in the linea alba. Usually contains extraperitoneal fat.
Asymptomatic/local symptoms (treat with surgery)
Defect in the femoral canal.
Below and lateral to the pubic tubercle. Loss of groin crease. Typically elderly, thin female.
Paediatric inguinal hernia
Processes vaginalis- This is the hole in the peritoneal cavity where the testes descend through. Usually closes but sometimes it doesnt and areas of bowel can come through.
Two types- indirect and direct
Indirect- lateral to inferior epigastric vessels
Direct- medial to inferior epigastric vessels.
Indirect inguinal hernia
May reach scrotum.
Congenital hernias are indirect
Can be controlled by digital pressure
Direct inguinal hernia
Through transversalis fascia
Poorly controlled by digital pressure
Complications of hernias
Chronic neurogenic pain
Testicular pain and atrophy
Acute urinary retention
Operations performed on hernias
Suture, open mesh, laparoscopic
Herniotomy- excision of peritoneal sac
Herniorraphy- repair of defect in wall
Post op advice for people with hernias
No driving for a week
Avoid heavy lifting.
Hepatitis spread by sex, blood, or from mother to child
Hep B or Hep C
Lab tests for hep B
Hep B surface antigen present (HBsAg)
If individual is highly infectious they will have Hep B e surface antigen (HBeAg)
More antigen will be present in more infectious individuals
Children and acute hep B
Child is more likely to develop chronic Hep B
Which Hepatitis virus is most likely to become chronic?
Which peiple are at risk of developing Hep B?
Densely populated areas
Muiltiple sexual partners
IV Drug use
Labs for Hep C
Screen for Hep C IgG antibodies
Hep C virus RNA test- positive will mean viral RNA present
Always as a co-infection or superinfection with Hep B. (co-infection when you are infected with both at the same time, super infection is affected by Hep D afterwards)
Worsens symptoms of hep B
How is Hepatitis A spread?
Faecal- oral route
Who is most likely to get infected with Hep A?
Densely populated and poor hygienic areas
Describe Hep A infection?
Labs for Hep A
IgM hep A present
How is hepatitis E spread?
Faecal oral route
Who is hepatitis E most common in?
Travellers (more common in tropical areas)
How does Hep E present?
Acute- similarly to hep A.
SERIOUS IN PREGNANT WOMEN
Management of acute hepatitis
Monitor for encaphylopathy
Monitor for resolution
Notify public health
Test for other infections and vaccinate against these
Management of chronic hepatitis
Vaccination against other hepatitis
Treat before established cirrhosis sets in.
Drug treatment of hepatitis
Peginterferon Alpha 2a- stimulates immune system to attack virus.
Describe the formation of bilirubin.
Old red blood cells are eaten by macrophages. The haemoglobin gets broken down into heme and globin. The globin goes on to form amino acids. However the haem is further broken down into iron and protoporphyrin.
This is then converted to unconjugated bilirubin (which is insoluble in water). Therefore to get to the liver it needs albumin to transport it in the blood.
When it reaches the hepatocyte, unconjugated bilirubin is converted by uridine glycorynl transferase (UGT) to conjugated bilirubin.
Conjugated bilirubin travels to the bile duct where it becomes concentrated.
On eating- bile is secreted into the duodenum where it reacts with microbes to form urobilinogen. THis becomes spontaneously oxidised to urobilin (which is excreted in faeces or recycled by the livers and kidneys).
What does an increase in unconjugated bilirubin do?
Increase could be due to increased breakdown of reb blood cells prematurely (extravasculation haemolytic anaemia) or due to red blood cells not forming right (ineffective haematopoesis).
This leads to an increase in unconjugated bilirubin in the blood and therefore jaundice.
What does an increase in conjugated bilirubin do?
Pigmented gall stones
Physiologic jaundice of the newborn
Decreased UGT levels (uridine glutamyl transferase) therefore no conversion of UCB to CB
UCB is not soluble and can build up in places like the brain
Decreased UGT- infection, stress and starvation exacerbate this.
Crigler Naff syndrome
No UGT- fatal
Dubin Johnson Syndrome
Conjugated bilirubin can't move into bile canniculi and therefore build up in the hepatocyte.
Something obstructs the flow of bile- leads to back up of bile into the blood.
Obstruction of the cystic duct (most likely due to gallstones) causing back up of bile and the gall bladder to enlarge.
Symptoms of acute cholecystitis
Biliary colic pain
Pain becomes more localised and causes severe RUQ pain
Pain felt when gallstones temporarily obstruct the cystic duct. Pain is constant. Exacerbated by eating (especially fatty foods). Nausea and vomiting.
Pain may radiate over right shoulder or spontaneously stop. May need opiate analgesisa
Common bile duct stones
Stones in the common bile duct
Presents as biliary colic, fever, jaundice.
Investigations into common bile duct stones
Increased serum bilirubin
Increased ALP and GGT
Investigations into acute cholecystitis
Raised ALP and GGT
Slightly elevated serum bilirubin
Ultrasound will show thickened bile duct walls/enlarged bile duct.
Management of acute cholecystitis
Nil by mouth
Wait for it to settle and then perform cholecystectomy.
Cancer of the biliary tree. Could be intrahepatic (in the bile ducts inside the liver) or extra hepatic (in the cystic, hepatic, gallbladder). Associated with primary sclerosing cholangins, chronic infection.
Usually presents with jaundice
Investigations into cholangiocarcinoma
Treatment of cholangiocarcinoma
Resection or radical chemotherapy
Cancer of the gallbladder
Benign polyps- adenomas
Related to calcification which is the final stage in acute cholecystitis. Also polyps greater than 10mm in diameter are likely to become malignant.
Symptoms of acute pancreatitis
Epigastric pain that radiates through to the back
In severe cases- tachycardia, hypotension, Cullens sign and Grey Turners sign.
Causes of acute pancreatitis
Alcohol, viral infection (cocksackie), gallstones, pancreatic tumours, drugs.
Anything that leads to increased intracellular calcium. Blockage of the pancreatic duct leads to early activation of trypsinogen to form trypsin. This somehow leads to increased intrapancreatic pressure and increased calcium depositation.
Blood tests and investigations
Causes of chronic pancreatitis
Chronic alchohol consumption
Symptoms of chronic pancreatitis
Epigastric pain- may be episodic
Malabsorption or diabetes
Gallstone related jaundice
Treatment of chronic pancreatitis
Opiate analgesia and NSAIDs for the pain.
Describe autoimmune pancreatitis
Defect in the PRSS1 gene that is involved with the activation of trypsin. IgG4 related. Dense lymphoblastic infiltrate. Reversed by corticosteroids.