Gram negative bacilli Flashcards
What are the cell wall/membrane antigens associated with gram negative bacteria
O=cell wall antigen
H=flagella antigen
K= capsule antigen
Endotoxin= Lipid A
Describe Vibrio cholerae in terms of morphology, virulence factors, major illnesses associated w/ the microbe, and transmission rout
Morphology= G negative curved/comma shaped bacillus
Virulence= cholera toxin
Illness= massive diarrhea “rice water stools” caused by cholera toxin, minimal to no blood because bacteria are noninvasive (stay in intestine)
Transmission: ingestion of bacteria, mainly in tropical asia/india, africa, s. america
True or false few organisms are needed to be ingested to cause cholera
False= must ingest large # of bacteria to cause cholera
What is the treatment for cholera
Replacement of fluids via balanced IVF’s or oral glucose/electrolyte replacement
only use Abx for severely compromised pts
Describe Vibrio parahaemolyticus in terms of morphology, major illnesses associated w/ the microbe, and transmission route
Morphology= G negative curved/comma shaped bacillus
Illness= mild gastroenteritis
transmission= shellfish in Asian pacific costal waters, rare in US
Describe Vibrio vulvificus in terms of morphology, major illnesses associated w/ the microbe, and transmission route
Morphology= G negative curved/comma shaped bacillus
Illness= acute gastroenteritis, septicemia, and severe cellulitis/hemorrhagic bullae/narcoticizing fasciitis
transmission= raw seafood or warm water
Describe Campylobacter jejuni in terms of morphology, culture enviroment, major illnesses associated w/ the microbe, transmission route, and treatment
Morphology= G negative S or gull wing” shaped bacillus
Culture enviroment=microaerophilic w/ increased CO2, can grow in bile salts
Illnesses = #1 or #2 cause of gastroenteritis in N. America
Transmission=fecal oral route from undercooked chicken contaminated beef or raw milk
Treatment
- typically no Abx just rehydrate
- may use Abx in compromised pts or to eliminate carrier state
Describe Heliobacter pylori in terms of morphology, major illnesses associated w/ the microbe, and dx testing
Morphology= G negative curved shaped bacillus
Illness= gastric ulcers likened w/ stomach Ca
Testing= Breath urease test or endoscopy/biopsy
Describe Salmonella in terms of morphology, major illnesses associated w/ the microbe (include signs/symptoms), transmission route, and treatment
Morphology= G negative bacillus (Enterobacteriaceae family)
Illness
- gastroenteritis
- Typhoid (Enteric) fever= persistent fever, headache, malaise, rose spots on skin
Transmission= contaminated food and water (poultry, reptiles or human typhoid carries)
Treatment= no Abx unless compromised pt, infants, elderly, and typhoid
- susceptibility is needed
In a carrier state for typhoid where do the bacteria localize
Gallbladder, liver, spleen, sometime bone
True or false Salmonella enterica is the only species we care about
True, only one species but multiple serotypes
Describe Shigella in terms of morphology, virulence, major illnesses associated w/ the microbe (include signs/symptoms), transmission route, and treatment
Morphology= G negative bacillus (Enterobacteriaceae family)
Virulence= Shiga toxin (exotoxin), endotoxin, invasive enzymes
Illness
-pussy/bloody diarrhea (dysentery) caused by combo of Shigella toxin(diarrhea) and Endotoxin (pus and bleeding)
Transmission= fecal oral route, via small # of bacteria to make you sick
Treatment= rehydration and 3rd generation cephalosporin need Abx susceptibility
What is the most frequently isolated antigenic group of Shigella
Group D
Describe Escherichia coli in terms of morphology, virulence factors, major illnesses associated w/ the microbe (include signs/symptoms), transmission route, and treatment
Morphology= G negative bacillus (Enterobacteriaceae family)
Virulence= normal microbiota, but can become pathogenic from plasmid
Illness
- UTI=75-80% of all UTIs
- Travelers diarrhea= ETEC releases cholera like toxin, no mucus or blood
- Hemorrhagic diarrhea= STEC and EHEC produce shiga toxin
- Hemolytic uremic syndrome= from STEC or EHEC
- Wound infection
Transmission= fecal contaminated meat/food like cows or chicken
Treatment= possible Abx but need susceptibility
Describe Yersinia enterocolitica in terms of morphology, major illnesses associated w/ the microbe (include signs/symptoms), transmission route,
Morphology: G negative bacillus (Enterobacteriaceae family)
Illness: mild bloody diarrhea (bacteria are invasive)
Transmission: contaminated pork, milk, water, fecal oral (may shed for 90days after symptoms)