Vibrio And non fermenters Flashcards
Classification of Vibrio
Halophilic - need salt 7-10%
Non - Halophilic - cannot grow at high salt
Halophilic Vibrio includes
V. Parahemolyticus
V. Alginolyticus
V. Vulnificus
Non Halophilic Vibrio includes
V. Cholerae
V. Mimicus
Gardener and Venkatraman classification of Vibrio
Vibrio - Vibrio cholera : 1) O1 2)O139 3) O2-O138
O1 is further classified into
Classical
Eltor and
Eltor variants
Eltor for any test
For any sensitivity
For carriers
Test - Positive
Sensitivity - Resistant
Carriers - more
Infectivity dose of Vibrio cholera
10^8 CFU/ml - high infectivity dose (most of Vibrio killed by acid in stomach)
In cholera, mucus is crossed by which enzyme
Mucinase
Intestinal epithelial adhesion in cholera is done with the help of
Toxin coregulated pilus (TCP)
Which toxin breaks tight junctions in case of cholera
Zona occludens toxin
Cholera toxin is coded by which gene
CTx gene
Cholera toxin mechanism of action
Fragment A : MOA - Activates adneylate cyclase - increases cAMP - phosphorylation of CFTR - ions secreted in lumen - Rice water stool
Fragment B - Binds to GM1 ganglioside
Which toxin increases cAMP
CAMP
Cholera toxin
Anthrax toxin
ETEC (labile)
Pertussis
Incubation period of Cholera
1-5 days
Carrier of Cholera
Eltor»_space; Classical
Clinical features of Cholera
Rice water stools - Sudden onset, mucus flakes, fishy odor
Transport medium used for Diagnosis of cholera
Venkatraman Ramakrishna medium
Carry Blair medium
Microscopic Findings of V. Cholera
Comma shaped, curved Gram -ve organism
Fish in stream appearance
Motility shown by V Cholera
Darting/Shooting star Motility
Monotrichous flagella
Fish in stream appearance
MacConkey agar finding for V. Cholera
Non lactose fermenter
Blood agar and Nutrient agar findings for V Cholera
Blood agar - Greenish Hemolysis
Nutrient agar - Translucent colonies (bluish tinge in light)
Gelatin swab finding for V. Cholera
Napiform/turnip liquifaction
Enrichment media used for V. Cholera
Alkaline peptone water
Monsours taurocholate tellurite peptone water
Selective media used for cholera
TCBS (Thiosulfate citrate bile salt sucrose)
ABSA (Alkaline bile salt agar)
GTTA (Gelatin Taurocholate Trypticase tellurite agar) - Black centre and halo
Which selective media can be used to differentiate between Sucrose fermenter and Non Sucrose fermenter
TCBS ( Thiosulfate citrate bile salt sucrose)
Indicator - Bromothymol blue
Biochemical tests used for cholera
CCOINSS
C - Cholera red reaction
C - Catalase +ve
O - Oxidase +ve
I - Indole test +ve
N - Nitrate reduction +ve
S - Sucrose lysis +ve
S - String test
In cholera red reaction, Red color is due to
Nitrosoindole Compound
String test
Treat the sample with 0.5% deoxycholate - Vibrio damage - DNA Comes out - Strings seen
Treatment of Cholera
ORS with or without Fluids
Antibiotics if needed - Doxycycline (adults), Azithromycin (Children, Pregnancy)
Vaccine for Cholera
Live oral vaccine
Vibrio mimicus is known to cause
Mimicus - Macchi food
Gasteroenteritis due to seafood consumption
Vibrio Parahemolyticus is known to cause
Gasteroenteritis (seafood)
Wound infection
Kanagawa phenomenon is shown by
Vibrio Parahemolyticus
Kanagawa phenomenon
On Wagatsuma agar (Blood agar with 2-4% salt)
Pathogenic strains - Hemolytic
Non pathogenic strains - Non Hemolytic
Vibrio vulnificus can cause
Normal individuals - Gasteroenteritis
Immunocompromised - Sepsis
Which Halophilic Vibrio can be a lactose fermenter
V. Vulnificus
Vibrio Alginolyticus is known to cause
Conjunctivitis
Otitis media
Which Halophilic Vibrio is most tolerant to Nacl
V Alginolyticus
Which Vibrio species shows Swarming motility
V. Parahemolyticus
V. Alginolyticus
Examples of Non fermenters
Uses sugars oxidatively
Pseudomonas
Burkholdiera Mallei
Burkholdiera Pseudomallei
Acinetobacter Baumanni
Pseudomonas features
Gram negative bacillus
Catalse+ve
Oxidae +ve
Virulence factors of Pseudomonas
Capsule +
Pigments shown by Pseudomonas
Pyocyanosis (Blue green pigment)
Pyoverdine - Greenish yellow
Pyorubin - Red
Pyomelanin - Brown black
Pyocyanosis enhances on which medium
Kings medium
Alginic acid is found in
Mucoid strains of Pseudomonas
Biofilm production
Toxins of Pseudomonas and MOA
Exotoxin A - decrease protein synthesis by ADP phosphorylation of EF2
Clinical features of Pseudomonas
PSM HUB
Pneumonia (HAP, VAP)
Swimmers ear/Simple otitsi externa
Hot tub Folliculitis
Shanghai fever - Sepsis + enteric disease
Meningitis
UTI (Catheter Associated)
Burn wound infections
Green Nail syndrome
Microscopic Findings of Pseudomonas
Gram -ve
Can be motile
Pigment enhanced by Kings medium
Iridescence property shown by Pseudomonas
Large opaque colonies with metallic shine
Selective media used for Pseudomonas
Cetrimide agar
Pseudomonas Mnemonic
PSEUDOMONAS
P - Pigments - enhances on Kings medium
S - Sweet/Fruity odor
E - Iridescence (Colonies metallic shine)
U - Use sugar Oxidatively
MO - Motile
N - Non lactose fermenter
A - Agar beta hemolytic
S - Selective - Cetrimide agar
Pseudomonas is susceptible to
Silver salts
Silver sulphonamide in topical burn creams
Burkholdiera Pseudomallei causes
Meliodosis
Burkholdiera Pseudomallei is also known as
Vietnam time bomb or
Whitemore bacillus
Culture used for Burkholdiera Pseudomallei
ASA (Ashdown agar) - Crystal Violet with gentamicin
Microscopic Findings of burkholdiera Pseudomallei
Safety pin appearance
Treatment of Burkholdiera Pseudomallei
Carbapenem, Imipenem
Burkholdiera Mallei causes
Disease in animals (Glanders disease)
Diagnosis of Burkholdiera Mallei
Strauss reaction - inoculation in Guinea pig - testicular swelling
Clinical features of Burkholdiera Mallei
Skin ulcers
Pneumonia
Lymphadenopathy
Which Burkholdiera is most common and most potent
Burkholdiera Cepacia
Burkholdiera Cepacia is associated with
Chronic granulomatous disease
And Cystic fibrosis
Burkholdiera Cepacia Mnemonic
CePaCiA
Most common Burkholdiera
Most Potent
A/w Chronic Granulomatous disease and Cystic fibrosis
A - Antibiotic resistance
