Other Gram - Bacteria Flashcards
fermentation of lactose
- fermentation of lactose –> pink colonies on MacConkey agar
- “lactose is key”
- “test with MacConKEE’s agar”
examples of lactose fermenting enteric bacteria
- Klebsiella
- E. coli
- Enterobacter
- Serratia (weak fermenter)
what does E. coli produce, and how does that work as lactose?
-
E. coli produces beta-galactosidase
- beta galactosidase breaks fown lactose into glucose and galactose
lactose fermenting enteric bacteria and EMB agar
- lactose fermenters grow as purple/black colonies
- E. coli grows colonies with a green sheen
properties of Neisseria
- gram - diplococci
- metabolic glucose
- produce IgA proteases
is N. gonorrhoeae intra or extra cellular?
- intracellular
- within neutrophils
2 types of Neisseria and what they ferment
- Meningococci
- “MeninGococci ferment Maltose and Glucose”
- Gonococci
- “Gonococci ferment Glucose”
properties of Gonococci Neisseria
- no polysaccharide capsule
- no maltose metabolized
- no vaccine due to antigenic variation of pilus proteins
- sexually or perinatally transmitted
what does gonococci Neisseria cause?
- gonorrhea
- septic arthritis
- neonatal conjunctivitis
- pelvic inflammatory dz (PID)
- Fitz Hugh Curtis Syndrome
how to prevent sexual transmission of gonococci Neisseria?
- condoms
how to prevent neonatal blindness caused by gonococci Neisseria?
- erythromycin eye ointment
gonococci Neisseria–treatment
- ceftriaxone
- (azithromycin or docycycline) for possible chlamydial coinfection
properties of meningococci Neisseria
- polysaccharide capsule
- maltose fermentation
- vaccine–type B not widely available
- transmitted via respiratory and oral secretions
what does meningococci Neisseria cause?
- meningococcemia with petechial hemorrhages and gangrene of toes
- meningitis
- Waterhouse Friderichsen syndrome
- adrenal insufficiency
- fever DIC
- shock
meningococci Neisseria–prophylaxis in close contacts
- rifampin
- ciprofloxacin OR
- ceftriaxone
meningococci Neisseria–treatment
- ceftriaxone
- Penicillin G
properties of Bordetella pertussis
- gram -
- aerobic
- coccobacillus
Bordetella pertussis–virulence factors
- pertussis toxin–disable Gi
- tracheal cytotoxin
what does Berdetella pertussis cause?
- whooping cough
how to prevent bordetella pertussis?
- Tdap, DTaP vaccines
what may Bordetella pertussis be mistaken as, and why?
- may be mistaken as viral infection due to lymphocytic infiltrate resulting from immune response
properties of Campylobacter jejuni
- gram -
- comma or S shaped with polar flagella
- oxidase +
- grows at 42 deg C)
- “Campylobacter likes the hot campfire”
- fecal oral transmission through person to person contact or via ingestion of undercooked contaminated poultry or meat, unpasteurized milk
what does Campylobacter jejuni cause?
- bloody diarrhea especially in children
what is a risk factor for Campylobacter jejuni?
- contact with infected animals (dogs, cats, pigs) is also a risk factor
what is Camphylobacter jejuni a common antecedent of?
- Guillain Barre Syndrome
- reactive arthritis
properties of Vibrio cholerae
- gram -
- flagellated
- comma shaped
- oxidase +
- grows in alkaline media
- requires large incoculum (high ID50) unless host has dec gastric acidity
where is Vibrio cholerae endemic?
- developing countries
what does Vibrio cholerae cause and by what mechanism?
- produces profuse rice water diarrhea
- via enterotoxin that permanently activates Gs –> inc cAMP
what is Vibrio cholerae sensitive to?
- stomach acid–acid labile
what is necessary with a Vibrio cholerae infection?
- prompt oral rehydration
