Abdominal fever and other Salmonella infections; Flashcards
what is diarrhoea syndrome ?
3 or more stools daily
acute - <14 days
subacute 14-30 days
chronic- lasting more than 30 days
viral etiology of diarrhoea syndrome ?
rotavirus (transited through air)
adenovirus ?
norovirus - ?
bacterial etiology of diarrhea ?
shigella
vibrio cholera - most severe
ecoli
parasite etiology od diarrhea syndrome ?
lamblia giardia
what are the different types of diarrhea and their causes ?
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criteria for infectious diarrhea ?
watery diarrhea - rotavirus , vibrio cholera , salmonella
acute for 3 days and self limiting except for cholera - sever dehydration through rice stool - hypovolemic shock
bloody diarrhea / inflammatory - shigella , salmonella , enterohemrrhagic eccoli
lasts longer that watery diarrhea 2-7 days
and colon usually primary site
secretory diarrhea
D+V = s aureus , clostridium perfinges - 24hrs after ingestion
hospital acquired diarrhea
infants - rotavirus
adults - antibody associated diarrhea - clindamycin
travellers diarrhea
most cases 80 percent - enetrotoxigen related coli
shigella in contaminated food water
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criteria for infectious diarrhea ?
acute diarrhoea syndrome - lasting up to less than 14 days of diarrhoea
with the following symptoms - abdominal pain , nausea , vomiting , tenesmus
with
toxic infectious syndrome
EPIDEMIOLOGY of salmonella typhi ?
where there is the least amount of sanitation
east and southeast asia , africa
which SALMONELLA SPECIES CAUSES TYPHOID FEVER ?
Unlike other Salmonella species that primarily cause local intestinal inflammation
Salmonella Typhi and Paratyphi A, B, and C characteristically invade the gastrointestinal tract into the bloodstream, survive and reproduce within macrophages,
what is the RESERVOIR FOR SALMONELLA ENTERICA SEROTYPE TYPHI ?
and other salmonella species ?
only humans for salmonella enterica serotype typhi
other salmonella species have humans and animals as reservoirs - intestines , pigs , cows, chicken
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In typhoid fever and non
typhoidal salmonellosis, one important factor is important:
an asymptomatic
human carrier state exists for the agents of either form of the disease. The carrier state may last from
many weeks to years
.
what are the CHARACTERISTICS for salmonella ?
gram negative rod
hydrogen sulfide producing
facultative anaerobe
PERITICHOUS FLAGELLA
OXIdase negative
salmonella enterica serotype Enteritidis and typhimurium is resistant to gastric acid
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however S typhi High infectious dose required → NOT resistant against gastric acid
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typhoid toxin is exclusively produced by intracellular S. Typh
Salmonella cytolethal distending toxin (S-CDT), first described as the “typhoid toxin
DNA damage in eukaryotic cells.
TRANSMISSION in typhoid fever ?
fecal to oral - through contaminated stool
or through contaminated food and drink
what is the PATHOPHYSIOLOGY OF TYPHOID FEVER ?
oral uptake of a large number of organisms are needed to cause infection unlike shigella few as 10
migration to peyer patch at distal ileum
infection of macrophages - nd disseminates into organs of the mononuclear phagocyte system (e.g., lymph nodes, liver, spleen, bone marrow)
infected macrophages go int the blood stream - and this causessepticemia
what is the INCUBATION PERIOD FOR TYPHOID FEVER ?
5-30 days
after 3 weeks - chronic salmonella carriers
what are the CLINICAL SYMPTOMS IN TYPHOID FEVER ?
week 1
hyperthermia
STEP LADDER RISE IN TEMPERATURE (40-41°C) over 4 to 5
days, accompanied by headache
RELATIVE bradycardia - usually heart rate increases with rise in body temperature
but in typhoid fever this phenomena is significantly reduced (thats why it is relative bradycardia)
constipation
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week 2
fever -
no chills
and unresponsive to antipyretics
mild HEPATOSPLENOMEGALY
ROSE COLOURED SPOTS (rose coloured exanthema or rash) - in the upper chest and abdomen - mostly around navel
TYPHOID TONGUE - grey yellow coated tongue with red edges
abdominal pain and headache
diarrhea - YELLOW GREEN - pea soup - PURULENT BLOODY NECROSIS OF PEYER PATCHES
ILEUS BEcauses Peters patches become swollen
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weeks 3
all features of week 2
The patient will appear in the “TYPHOID STATE” which is a state of prolonged apathy,
toxemia,
delirium, disorientation and/or coma.
if left untreated high chance of gastrointestinal ulceration with bleeding and perforation - peritonitis
in rare cases - meningitis / myocarditis
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WEEK 4
RECOVERY
how is TYPHOID FEVER DIFFERENT FROM PARATYPHOID FEVER ?
Symptoms usually begin six to thirty days after exposure and are the same as those
of typhoid fever
Gradual onset of a high fever over several days
Without
treatment symptoms may last weeks or months.
DIAGNOSIS OF TYPHOID FEVER ?
lab anemia leukocytosis or leukopenia --absolute eosinopenia ! abnormal liver function
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detecting pathogen
blood culture - detectable in starting one week of clinical syndrome
stool culture - Cultures may be positive from weeks 2–3, but they are often negative despite active infection
bone marrow culture - might be positive even after antibiotic treatmnet
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Produces hydrogen sulfide (H2S) on TSI agar (Triple sugar iron agar)
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SEROLOGY - WIDAL TEST - WEEK 2 ONWARDS
agglutinating antibodies against the O and H antigens of S. Typhi.
