GI infections Flashcards
What is the most common type of bacteria in the gut?
Bacteroides and GNR
Name two causes of oseophagitis?
CMV and candida infection
Name a cause of gastritis?
H.pylori
What is a liver abcess?
A liver abscess is a mass filled with pus inside the liver.[1] Common causes are abdominal conditions such as appendicitis or diverticulitis due to haematogenous spread through the portal vein.[2] It can also develop as a complication of a liver injury.
Pyogenic liver abscess, which is most often polymicrobial, accounts for 80% of hepatic abscess cases in the United States.
Amoebic liver abscess due to Entamoeba histolytica accounts for 10% of cases. The incidence is much higher in developing countries.
Fungal abscess, most often due to Candida species, accounts for less than 10% of cases.
What are symptoms of a gallbladder infection?
Charcot triad: jaundice, pain and fever
What is a common cause of pancreatitis?
Mumps
What are common causes of enteritis of the small intestine?
Rotavirus, norovirus, GNR
What are the common causative agents of infection of the large bowel?
Colitis? CMV, clostririduum, TB
Diverticulitis? GNR, anaerobes
What are the different parts of the Bristol stool chart?
Bristol stool chart = 1-7
Type 1 is hard, lumpy (like maltersers)/ pellet like
Type 2 - is hard, sauasage like but with lumps (like a lion bar)
Type 3 -(flake like) sausage with cracks
Type 4 - smooth (like a ripple bar)
Type 5 - soft pellets (like revels)
Type 6 - (soft like ice cream)
Type 7 - (watery like chocolate milk)
What is the most important thing to prevent in gastro-enteritis?
Dehydration
What is the most common risk factor for oesophagitis? What should you check for?
HIV status or immunocompromised
What is the 2nd most common causative agent of oesophagitis?
CMV
What is a useful way to test for oesophagitis caused by CMV?
There was a significant association between the detection of owl’s eye inclusion bodies and positive CMV PCR (p < 0.001)
How is CMV treated?
Treat immunosuppression +/- ganciclovir
How is thrush treated?
Check HIV status and treat with fluconazole
What is a test for H pylori?
Urease breath test
CLO test Rapid urease test, also known as the CLO test (Campylobacter-like organism test), is a rapid diagnostic test for diagnosis of Helicobacter pylori.
What diseases can untreated H pylori cause?
Gastric cancer
Gastric MALT lymphoma
What is the treatment for H pylori?
PPI
Amoxicillin / metronidazole
Clarithromycin
1 week
What does it mean if diarrhea is watery?
What does it mean if the diarrhea is bloody?
Large intestine is affected
What is a staph aureus food infection like?
Its incubation period lasts one to six hours,[38] with the illness itself lasting from 30 minutes to 3 days
Spores survive, despite organism dying in gut.
Caused by uncooked food
Gram positive
What is the incubation period of a S aureus infection?
Its incubation period lasts one to six hours,[38] with the illness itself lasting from 30 minutes to 3 days
What symptoms are more common in S aureus infection? Which one symptom is not common?
Vomiting
Fever
Abdo pain
(less chance of diarrhoea)
What is Clostridium perfringens?
Gram positive
Spore form once ingsted
Incubation time is between 18 and 24 hours after ingestion of contaminated food.
Resolves in 1 day
Can cause diarrhoea, abdo pain and fever.
What type of bacteria is clostridium perfringens?
Gram positive
What is the incubation period? How long does it last?
18-24 hours
But lasts once day
Which antibiotics increase risk of C. difficle?
Ones that start with C (+ A, E, I. O, U)
A - co-amoxiclav
E - ceftriaxone
I - clindamycin
O - ciprofloaxicin
U - PPI
How is a clostridium difficicle infection treated?
Mild - metronidazole (IV or oral)
Moderate/ severe - vancomycin (oral or rectal). Oral as cannot pass membrane
Recurrent infections - treat with Fidaxomicin
Therapy
What are the main symptoms of c difficile infection?
Foul smelling diarrhoea, dehydration, shock, pain
What are the two types of infection linked to Bacillus cereus?
Emetic (1-5 h) like S .aureus
Diarrhoeal (18-24h) like C difficule
Rice not heated enough
What medication should be given orally?
Vancomycin as doesn’t pass
What is the incubation of cholera?
1-5 days
Where has there been a recent outbreak of cholera?
Yemen
How is cholera treated?
Rehydration
Ciprofloxacin
What does salmonella typhi cause?
Enteric fever
What does salmonella typhi invade?
Peyer’s patches
What is the pathogenesis of salmonella typhi?
Incubation 5-12 days before infection starts
What is the pathogenesis of salmonella typhi?
How is salmonella typhi treated?
Ceftriaxone, ampicillin, meropenem (cell wall inhibition)
What is shigella?
Bloody diarrhea and tenesmus
Can cause reactive arhritis, conjuctivitus, HUS
Why should you not give antibiotics in E coli 0157
Causes more release of toxin
What is the incubation of campylobacter?
3 days
What can shigella cause?
HUS and reactive arthritis
What does giardia cause?
Flattened villi, lactose intolerance
What is Whipple’s disease?
Affects absorption caused by Tropheryma whippelii.
What type of testing can be done on stool?
MC and S
C diff antigen testing
Ova, cysts and parasites checking
What are the components of gram stains?
Crystal violet
Iodine
Alcohol
Safranin
Is staphylococcus aureus coagulase positive or negative?
Positive
Is staphlococcus epidermis coagulase positive or negative?
Negative
What separates the upper and lower respiratory tract?
Vocal folds
What is coryza?
Means runny or stuffy nose
What percent of sore throats/ pharyngitis are viral?
90%
What is an important bacterial cause of pharyngitis?
GAS - group A strep
What is Lemierre’s syndrome?
Fusobacterium necrophorim
Lemierre’s syndrome refers to infectious thrombophlebitis of the internal jugular vein. It most often develops as a complication of a bacterial sore throat infection in young, otherwise healthy adults. The thrombophlebitis is a serious condition and may lead to further systemic complications such as bacteria in the blood or septic emboli.
What is Lemierre;s syndrome?
Clots in jugular caused by fusobacterium necrophorum
What are some causes of pharnygitis?
90% viral e.g. coronavirus
Group A strep pygenes - beta haemolytic
Group B and C strep
Diptheria
EBV
Lemiere’s (rare)
What is Lancefield classification for?
Strep
Lancefield grouping is a system of classification that classifies catalase -negative Gram-positive cocci based on the carbohydrate composition of bacterial antigens found on their cell walls.
What classification can be used for streptococcus?
Lancefield
What is the Centor score?
For whether there is an exudate
What is the FEVERPAIN score?
The FeverPAIN Score for Strep Pharyngitis was developed to try and help assess which patients with pharyngitis have streptococcal infections.
What scoring systems can be used for pharyngitis?
FEVERPAIN and CENTOR
What is the treatment for GAS?
Phenoxymethylpenicillin
Common brand names: Penicillin V
(if allergic macrolide clarithomycin)
What can GAS cause if untreated?
Quinsy
Scalet fever
Rheumatic fever
Glumerulonephritos
Where is diptheria common?
Eastern europe and Bangladesh
How long is the incubation period for infectious mononucleosis?
1 month.
How should infective mononucleosis be managed?
Avoid contact sports for 6 weeks
