Typhoid Flashcards
which pathogen causes typhoid?
salmonella typhoid (bacterium)
which 2 main groups of salmonella enterica bacteria exist?
typhoid and non-typhoid
salmonella typhoid is a subspecies of which bacterium?
salmonella enterica
can typhoid be fatal?
yes
are salmonella bacteria gram negative or positive? which shape? do they have a capsule?
negative, rod shaped, encapsulated
s. typhoid targets which part of the intestine?
distal ileum
which cell type does s. typhoid target in the distal ileum? where do the bacteria get transported?
M-cells, the bacteria gets transported into the Peyer’s patches
are s. typhoid protected from antibodies? why is this?
yes, because of their polysaccharide later (contains VI capsular antigen virulence factor)
s. typhoid in distal ileum: which immune cells are recruited towards the site of infection? which immune cells are reduced?
monocytes and macrophages are recruited, leukocytes are reduced
what is the effect of monocytes and macrophage recruitment into the distal ileum? what can be the complication?
hypertrophy and necrosis of the epithelial cells -> can lead to ileal perforation and peritonitis
what happens after s. typhoid is endocytosed by macrophages?
it goes into a vacuole, but it prevents fusion with lysosomes -> keeps on replicating inside the macrophage
what happens with s. typhoid infected macrophages, via which system do they get transported?
to which organs? (name a few)
they get transported via the lymphatic system to:
- liver
- gall bladder
- spleen
- bone marrow
- lymf nodes
what happens when s. typhoid induces apoptosis of macrophages?
bacteria get released into the bloodstream -> sepsis
in which organ does s. typhoid remain in chronic typhoid?
what happens from time to time?
gall bladder
From time to time gets released into feces (swept along with bile)
typhoid: transmission route? example?
feces -> oral
from contaminated hands to objects or mouth e.g. food prepared with unwashed hands
can typhoid be transmitted from asymptomatic persons?
yes
is s. typhoid sensitive to gastric acid?
yes (so you need a lot of bacteria to cause an infection)
how fast do symptoms appear after contracting typhoid?
1-2 weeks
how long does typhoid fever take?
4-6 weeks
what are the intial symptoms of typhoid? (4)
- fever
- abdominal pain
- constipation -> diarrhea
- rose/salmon color spots on chest/abdomen
what are symptoms of typhoid that can occur as the infection spreads?
- hepatosplenomegaly
- dehydration, weakness, headaches, altered mental state (advanced cases)
typhoid: diagnosis?
blood culture, stool culture
typhoid: diagnosis in asymptomatic people?
bile culture
typhoid: treatment?
management of symptoms: fluid/electrolytes, NSAIDs
antibiotics (e.g. ceftriaxone)
typhoid: treatment of carriers?
antibiotics, removal gall bladder
what are the vaccines for typhoid?
intramuscular (inactivated) or oral (live)
