SEMR: Gram (-) bacilli Flashcards by JHOANNA LYNN LUMBOY

aka enterics or coliforms

Enterobacteriaceae

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all enterobacteriaceae are oxidase negative except for

Plesiomonas shigelloides

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all enterobacteriaceae are motile at body temperature except

klebsiella, shigella, yersinia KYS

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Enterobacteriaceae
Opportunistic Members

UTI, Septicemia, CNS and diarrheal diseases

Disease syndromes
1. Uropathogenic E. coli
2. Enterotoxigenic E.coli (ETEC)
3. Enteroinvasive E. coli (EIEC)
4. Enterophatogenic E. coli (EPEC)
5. Enterohemorrhagic E. coli (EHEC)
6. Enteroadherent E. coli (EAEC)

Escherichia coli

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Enterobacteriaceae
Opportunistic Members
Escherichia coli

-Most common cause of UTI in humans
-Virulence factor :
1. pili
2. cytolysins
3. aerobactin

Uropathogenic E. coli

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Enterobacteriaceae
Opportunistic Members
Escherichia coli

Virulence factor:
adherence to epithelial cells

Pili

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Enterobacteriaceae
Opportunistic Members
Escherichia coli

Virulence factor: inhibit immune effector cells

Cytolysins

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Enterobacteriaceae
Opportunistic Members
Escherichia coli

Virulence factor: chelate iron

Aerobactin

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Enterobacteriaceae
Opportunistic Members
Escherichia coli

Also known “Montezuma’s revenge” or “turista”

Enterotoxigenic E. coli (ETEC)

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Enterobacteriaceae
Opportunistic Members
Escherichia coli

Disease
-Epidemic (infant) diarrhea and traveler’s diarrhea

Virulence factor
-Fimbria
-Heat-labile (LT) and heat stable (ST) enterotoxins

Enterotoxigenic E. coli (ETEC)

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Enterobacteriaceae
Opportunistic Members
Escherichia coli

Virulence factor
-Invades enterocytes causing Shigella like infection

Enteroinvasive E. coli (EIEC)

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Enterobacteriaceae
Opportunistic Members
Escherichia coli

Disease
-Dysentery and Bloody stools

Other Characteristics- Sereny test (+)
-Strains can be non-motile or non-lactose fermenter

Enteroinvasive E. coli (EIEC)

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Enterobacteriaceae
Opportunistic Members
Escherichia coli

Virulence factor
-Bundle-forming pilus for attachment to cells
of the small bowel

Enteropathogenic E. coli (EPEC)

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Enterobacteriaceae
Opportunistic Members
Escherichia coli

Disease:
-Infantile diarrhea (watery with mucus but no blood)

Enteropathogenic E. coli (EPEC)

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Enterobacteriaceae
Opportunistic Members
Escherichia coli

Also known as Verotoxic E.coli (VTEC)

Enterohemorrhagic E. coli(EHEC)

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Enterobacteriaceae
Opportunistic Members
Escherichia coli

Virulence factor
-Cytotoxin (Verotoxin I & II) similar to Shiga toxin
-Serotype 0157:H7 strain (STEC) (sorbitol-MAC and
MUG negative)

Enterohemorrhagic E. coli(EHEC)

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Enterobacteriaceae
Opportunistic Members
Escherichia coli

Disease
-Hemorrhagic colitis and hemolytic uremic syndrome

Enterohemorrhagic E. coli(EHEC)

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Enterobacteriaceae
Opportunistic Members
Escherichia coli

Enteroadherent E. coli

-Associated with UTI and diarrheal disease

Diffusely adherent E.coli (DAEC)

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Enterobacteriaceae
Opportunistic Members
Escherichia coli

Enteroadherent E. coli

-Adhere to HEp2 in a aggregative “stacked-brick “
pattern
-Produces watery diarrhea

Enteroaggregative E.coli (EAEC)

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Enterobacteriaceae
Opportunistic Members

Friedlander’s bacilli

Klebsiella

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Enterobacteriaceae
Opportunistic Members

Disease syndromes
-Respiratory tract (pneumonia) ,wound, urinary tract,
blood (septicemia) ,and CSF (Meningitis) infections

B-C. Klebsiella
(Friedlander’s bacilli) and
Enterobacter

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Enterobacteriaceae
Opportunistic Members

-May be encapsulated and appears as mucoid colonies
that tend to “string”.
-Klebsiella is Associated with plasmid-mediated ESBL’s

Klebsiella(Friedlander’s bacilli) and
Enterobacter

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Important IMVC Reactions for Lactose Fermenters

Indole: +
MR: +
VP: -
Citrate:-

E. coli

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Important IMVC Reactions for Lactose Fermenters

Indole: -
MR: -
VP: +
Citrate: +

K. pneumoniae subs. pneumoniae

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Important IMVC Reactions for Lactose Fermenters Indole: + MR: + VP: - Citrate: +

K. pneumoniae subs. oxytoca

Important Decarboxylase Reactions for Lactose Fermenters LDC: + ODC: - ADH: -

K. pneumoniae subs. pneumoniae K. pneumoniae subs. oxytoca

Important Decarboxylase Reactions for Lactose Fermenters LDC: + ODC: + ADH: -

E. aerogenes

Important Decarboxylase Reactions for Lactose Fermenters LDC: - ODC: + ADH: +

E. cloacae

Enterobacteriaceae Opportunistic Members Virulence factor -Nosocomial and opportunistic pathogens causing bacteremia, septicemia, urinary tract, respiratory tract (pneumonias) and wound infections. -ONPG Positive

Serratia and Citrobacter

Enterobacteriaceae Opportunistic Members Serratiaand Citrobacter produces a red pigment (prodigiosin)

S. marcescens

Enterobacteriaceae Opportunistic Members Serratiaand Citrobacter produces Lipase, Gelatinase and DNase.

S. marcescens

Enterobacteriaceae Differentiation of Tribe Proteeae Reaction Indole: - MR/VP: +/- Citrate: + Urease: + H2S: + ODC: + Motility: s/+

P. mirabilis

Enterobacteriaceae Differentiation of Tribe Proteeae Reaction Indole: + MR/VP: +/- Citrate: d Urease: + H2S: + ODC: - Motility: s/+

P. vulgaris

Enterobacteriaceae Differentiation of Tribe Proteeae Reaction Indole: + MR/VP:+/- Citrate:+ Urease: +/- H2S:- ODC:- Motility: +

Prov. stuartii

Enterobacteriaceae Differentiation of Tribe Proteeae Reaction Indole:+ MR/VP:+/- Citrate: + Urease: + H2S:- ODC:- Motility:+

Prov. retgerri

Enterobacteriaceae Differentiation of Tribe Proteeae Reaction Indole:+ MR/VP: +/- Citrate: - Urease: + H2S: - ODC: + Motility: +

M. morganii

Enterobacteriaceae Primary Intestinal Pathogens -has 7 subspecies (1, 2, 3a, 3b, 4, 5, 6) -Almost all clinical isolates are of Subgroup I

Salmonella

Enterobacteriaceae Primary Intestinal Pathogens Citrate V Gas + H2S V LDC + ODC +

Choleraesuis

Enterobacteriaceae Primary Intestinal Pathogens Citrate - Gas - H2S - LDC - ODC +

Paratyphi

Enterobacteriaceae Primary Intestinal Pathogens Citrate - Gas - H2S + LDC + ODC -

Typhi

Enterobacteriaceae Primary Intestinal Pathogens Virulence Factors -Fimbria, ability to transverse intestinal mucosa, enterotoxin (gastroenteritis)

Salmonella enterica subsp. enterica

Enterobacteriaceae Primary Intestinal Pathogens Clinical Infections i. Acute gastroenteritis or food poisoning ii. Enteric Fever (Typhoid fever) iii. Bacteremia iv. Carrier state

Salmonella enterica subsp. enterica

Enterobacteriaceae Primary Intestinal Pathogens Clinical Infections: Salmonella enterica subsp. enterica -Associated with S. Typhi and S. Paratyphi -Isolated in blood at (weeks 1 to 2), in stool (weeks 2 and 3), and in urine (weeks 3 and 4)

Enteric Fever (Typhoid fever)

Enterobacteriaceae Primary Intestinal Pathogens Clinical Infections: Salmonella enterica subsp. enterica Associated with S. Typhimurium, S. Paratyphi and S. Choleraesuis

Bacteremia

Enterobacteriaceae Primary Intestinal Pathogens Clinical Infections: Salmonella enterica subsp. enterica harbor organisms in the gallbladder

Carrier state

Enterobacteriaceae Primary Intestinal Pathogens -Appears as metallic colonies with a black ring in Bismuth sulfite agar. -Diagnosed with WIDAL'S TEST in reference laboratories.

Salmonella enterica subsp. enterica

Enterobacteriaceae Primary Intestinal Pathogens Motile H2S (+) Exp. Paratyphi A Lysine Decarboxylase (+) Infectious Dose: 10^6

Salmonella

Enterobacteriaceae Primary Intestinal Pathogens Non-motile H2S (-) Lysine Decarboxylase (-) Infectious Dose: 100-200

Shigella

Enterobacteriaceae Primary Intestinal Pathogens Mannitol – ONPG V ODC – ONPG – Serogroup A

S. dysenteriae

Enterobacteriaceae Primary Intestinal Pathogens Mannitol + ONPG – ODC – ONPG – Serogroup B

S. flexneri

Enterobacteriaceae Primary Intestinal Pathogens Mannitol + ONPG V ODC – ONPG – Serogroup C

S. boydii

Enterobacteriaceae Primary Intestinal Pathogens Mannitol + ONPG V + ODC + ONPG + Serogroup D

S. sonnei

Enterobacteriaceae Primary Intestinal Pathogens Virulence Factors -Mediate attachment and invasion of mucosal cells. -S. dysenteriaeproduces neurotoxin and enterotoxin -Other species produce only enteroxin

Shigella

Enterobacteriaceae Primary Intestinal Pathogens Clinical Infections -Shigellosis or bacillary dysentery i. First Stage involves watery diarrhea ii. Dysenteric phase - Bloody and mucoid stools

Shigella

Enterobacteriaceae Primary Intestinal Pathogens Disease §Bubonic (Glandular) and Pneumonic Plaque

Yersinia pestis

Enterobacteriaceae Primary Intestinal Pathogens Laboratory Diagnosis -Bipolar staining "safety pin appearance" -Exhibit a cauliflower appearance at 48 hrs in SBA -Exhibit a “stalactite pattern” in broth culture -Preferential growth at 25°C to 30°C

Yersinia pestis

Enterobacteriaceae Primary Intestinal Pathogens Disease -Acute enteritis (enterocolitis) -Arthritis and Erythema nodosum

Yersinia enterocolitica

Enterobacteriaceae Primary Intestinal Pathogens Laboratory Diagnosis -Bipolar staining "safety pin appearance" -Bull’s eye colonies in CIN agar in 48 hours -Preferential growth at 25°C to 30°C, Motile at 25°C

Yersinia enterocolitica

Enterobacteriaceae Primary Intestinal Pathogens Disease Pseudotubercles

Yersinia pseudotuberculosis

Enterobacteriaceae Primary Intestinal Pathogens Laboratory Diagnosis -Bipolar staining "safety pin appearance" -Motile at 18°C to 22°C

Yersinia pseudotuberculosis

Enterobacteriaceae Primary Intestinal Pathogens Yersinia TSI Yellow/Orange Christensen Urea – Motility at 25°C – ODC – Sucrose –

Y. pestis

Enterobacteriaceae Primary Intestinal Pathogens Yersinia TSI Yellow/Orange Christensen Urea + Motility at 25°C+ ODC + Sucrose +

Y. enterocolitica

Enterobacteriaceae Primary Intestinal Pathogens Yersinia TSI Yellow/Orange Christensen Urea+ Motility at 25°C + ODC – Sucrose –

Y. pseudotuberculosis

Enterobacteriaceae Primary Intestinal Pathogens Yersinia Cefsulodin-Irgasan-Novobiocin inhibits gram (+) bacteria and most gram (-) bacilli

Cefsulodin

Enterobacteriaceae Primary Intestinal Pathogens Yersinia Cefsulodin-Irgasan-Novobiocin inhibits gram (+) cocci

Novobiocin

Enterobacteriaceae Primary Intestinal Pathogens Yersinia Cefsulodin-Irgasan-Novobiocin inhibits gram (-) bacteria

Crystal violet

O-F Media Change in color in both tubes. Enterobacteriaceae, Vibrio, Aeromonas, Plesiomonas and Chromobacterium

Fermentative

O-F Media Change in color in tubes w/out mineral oil (Open tube) Acinetobacter, Stenotrophomonas, Pseudomonas, Burkholderia

Oxidative

O-F Media No change in color in both tubes. Alcaligenes, Oligella

Nonsaccharolytic

Oxidase - Dark purple (Positive) Pseudomonas and Burkholderia

Positive

Nonfermenting Gram (-) Bacilli -75% of nonfermenters in nosocomial bacteremias and 5% to 15% of nosocomial infections -Causes bacteremia, wound infection, pulmonary disease (Cystic fibrosis patients), UTI, endocarditis, meningitis -Otitis media and JACUZZI/ HOT TUB syndrome

Pseudomonas aeruginosa

Pseudomonas aeruginosa Virulence Factor most important exotoxin; blocks protein synthesis

Exotoxin A

Pseudomonas aeruginosa Virulence Factor Polysaccharide polymer in mucoid strains

Alginate

Nonfermenting Gram (-) Bacilli Identifying Characteristics 1. Strict aerobic 2. Pigmented 3. FRUITY, GRAPELIKE or “CORN TORTILLA LIKE” Odor (2-aminoacetophenone) 4. Growth at 42°C 5. Grows in Cetrimide Agar 6. Acetamide Positive

Pseudomonas aeruginosa

Pseudomonas aeruginosa Pigments green- P.fluorescens/P. putida

Fluorescein (Pyoverdin)

Pseudomonas aeruginosa Pigments blue

Pyocyanin

Pseudomonas aeruginosa Pigments red

Pyorubin

Pseudomonas aeruginosa Pigments brown/black (P. stutzeri)

Pyomelanin

Nonfermenting Gram (-) Bacilli Clinical significance 1. Associated with ventilators, humidifiers, catheters, etc. 2. Opportunistic (1-3% of all nosocomial infection, 2ndmost commonly isolated non-fermenter); burns, trauma 3. About 25% of adults present in skin; 7% in pharynx 4. Ubiquitous; found in soil, water, foodstuffs

Acinetobacter spp

Nonfermenting Gram (-) Bacilli Acinetobacter spp Saccharolytic (glucose oxidizing), nonhemolytic strains.

A. baumannii

Nonfermenting Gram (-) Bacilli Acinetobacter spp Asaccharolytic, nonhemolytic strains.

A. lwoffii

Nonfermenting Gram (-) Bacilli Acinetobacter spp β-hemolytic strains.

A. haemolyticus

Nonfermenting Gram (-) Bacilli Identifying Characteristics 1. Plump, paired gram negative coccobacilli

Acinetobacter spp.

Nonfermenting Gram (-) Bacilli Acinetobacter spp. may exhibit PURPLISH hue (due to lactose oxidation)

A. baumannii

Nonfermenting Gram (-) Bacilli Acinetobacter spp. appears with a BLUE-GREY (cornflower blue) center in EMB.

A. baumannii

Nonfermenting Gram (-) Bacilli Clinical significance 1. Contaminants in blood drawing equipment (collection tubes, disinfectants, transducers, venous catheters, etc.) 2. Opportunistic (3rdmost commonly isolated among nonfermenters) 3. Intrinsic resistance commonly used antibacterial agent (aminoglycosides and beta lactams)

Stenotrophomonas maltophilia

Nonfermenting Gram (-) Bacilli Clinical significance “Melioidosis” -Bipolar staining (safety pin) in Gram Stain

Burkholderia pseudomallei

Nonfermenting Gram (-) Bacilli Burkholderia pseudomallei (pulmonar disease) formation of abscess

Melioidosis

Nonfermenting Gram (-) Bacilli Identifying characteristics 1. Bipolar staining (safety pin) in Gram Stain 2. Smooth to wrinkled colonies in BAP 3. Wrinkled and deep pink in Ashdown media 4. “Earthy odor” 5. “Sniffing” of plate is discouraged (work on BSC)

Burkholderia pseudomallei

Nonfermenting Gram (-) Bacilli “Associated with patients with CF (cystic fibrosis) and CGD (chronic granulomatous disease)

Burkholderia gladioli

Nonfermenting Gram (-) Bacilli -Glanders- zoonosis affecting horses,mules,donkeys. Formation of nodular lesions in lungs. Coughing, fever and release of infectious nasal discharge. -Potential bioterrorist agent -Nonmotile; non-pigmented colonies; no distinct odor

Burkholderia mallei

Nonfermenting Gram (-) Bacilli Biochemical Physiologic Characteristics Oxidase: - Pigment: Y Glucose: + Maltose: S/+ Growth at 42°: +/-

S. maltophilia

Nonfermenting Gram (-) Bacilli Biochemical Physiologic Characteristics Oxidase: - Pigment: - Glucose: - Maltose: - Growth at 42°: -

A. lwoffii

Nonfermenting Gram (-) Bacilli Biochemical Physiologic Characteristics Oxidase: - Pigment: - Glucose: + Maltose: +/- Growth at 42°: +

A. baumannii

Nonfermenting Gram (-) Bacilli Biochemical Physiologic Characteristics Oxidase: Pyoverdin: Pyocyanin Acetamide 42° Growth: Gelatin hydrolysis: LDC-ONPG:

Nonfermenting Gram (-) Bacilli Biochemical Physiologic Characteristics Oxidase: + Pyoverdin: + Pyocyanin Acetamide 42° Growth: - Gelatin hydrolysis: + LDC-ONPG: -

P. fluorescens

Nonfermenting Gram (-) Bacilli Biochemical Physiologic Characteristics Oxidase: + Pyoverdin: + Pyocyanin Acetamide 42° Growth: - Gelatin hydrolysis: - LDC-ONPG: -

P. putida

Nonfermenting Gram (-) Bacilli Biochemical Physiologic Characteristics Oxidase: + Pyoverdin: - Pyocyanin Acetamide 42° Growth: Gelatin hydrolysis: LDC-ONPG: +/-

B. cepacia

Nonfermenting Gram (-) Bacilli Biochemical Physiologic Characteristics Oxidase: + Pyoverdin: - Pyocyanin Acetamide 42° Growth: Gelatin hydrolysis: LDC-ONPG: -

B. pseudomallei

General Characteristics i. Dysgonic (slower or poorer growing) ii. Associated to SUBACUTE BACTERIAL ENDOCARDITIS iii. Normal biota of the oral cavity iv. Fail to grow in MacConkey v. Glucose fermenter (Require serum to the fermentative media) vi. Opportunistic bacteria

Fastidious Gram Negative Bacilli

HACEK Group 1. Aggregatibacter (formerly Haemophilus) aphrophilus 2.Aggregatibacter (formerly Actinobacillus) actinomycetemcomitans 3.Cardiobacterium hominis 4.Eikenella corrodens 5.Kingella spp.

Fastidious Gram Negative Bacilli HACEK Group -“foam loving” or needing high conc.of CO2 - Found in dental and gingival scrapings

Aggregatibacter aphrophilus

Fastidious Gram Negative Bacilli HACEK Group Virulence Factor -Collagenase and Leukotoxin Disease -Destructive periodontitis -Subacute bacterial endocarditis

Aggregatibacter actinomycetemcomitans

Fastidious Gram Negative Bacilli HACEK Group Microscopic characteristics -Short bacilli in pairs /chains -Bipolar staining “Morse Code” appearance.

Aggregatibacter actinomycetemcomitans

Fastidious Gram Negative Bacilli HACEK Group Colonial appearance -Pinpoint (24 hr ). With star shape with 4 to 6 point” in the center of the colony (48 hrs).

Aggregatibacter actinomycetemcomitans

Fastidious Gram Negative Bacilli HACEK Group Disease -Oral Infections -Subacute bacterial endocarditis Characteristics -Fermenter (dysgonic); pits agar -Pleomorphic gram (-) rod that tend to form rosettes or long filaments

Cardiobacterium hominis

Fastidious Gram Negative Bacilli HACEK Group Disease -Infections from human bites or fights (clenched fist wounds) -Cellulitis-needle use by drug addicts -Oral Infections and Subacute bacterial endocarditis

Eikenella corrodens

Fastidious Gram Negative Bacilli HACEK Group Characteristics -Non Fermenter; Pit agar; Chlorine bleachlike odor -Non-motile, oxidase positive, asaccharolytic, catalase negative; yellow pigment

Eikenella corrodens

Fastidious Gram Negative Bacilli HACEK Group Disease-major gram(-) bacteria in bone infections in chidren below 3y.o -Oral, blood, bone Infections -Subacute bacterial endocarditis

Kingella spp.

Fastidious Gram Negative Bacilli HACEK Group Kingella spp. Characteristics -Short bacilli to coccobacilli with squared ends in pairs/in chains -Fermenter (dysgonic); pits agar -Nonhemolytic (--) or β-hemolytic (K.kingae)

K. denitrificans

K.kingae

Fastidious Gram Negative Bacilli Infections Periodontitis; Local infection to fulminant infection (septicemia) esp. in neutropenic patients

Capnocytophaga

Fastidious Gram Negative Bacilli i. Microscopy -Thin and fusiform, spindle-shaped, coccoid and curved filaments ii. Culture Characteristics -Haze (gliding motility) on solid surface -opaque, shiny; pale beige or yellowish -Resemble HACEK in CO2 requirement §May produce yellow pigment; can resemble colonies of E.corrodens

Capnocytophaga

Fastidious Gram Negative Bacilli Infections -Systemic, pneumonic and cutaneous infection from animal (often cats) bites (zoonosis) Laboratory Diagnosis i. Microscopy -Coccobacilli (ovoid, filamentous or bacilli); Bipolar staining ii. Culture Characteristics -Grayish, non hemolytic, mucoid with narrow green to brown halo around the colony

Pasteurella multocida

Fastidious Gram Negative Bacilli Infections -Brucellosis (Undulant/Malta fever)- zoonosis-acquired through aerosol, percutaneous and oral routes; Category B biological agents ( high morbidity, low mortality) Symptoms: fever,malaise,headache,anorexia,myalgia Laboratory Diagnosis Microscopy -Coccobacili or bacilli Culture and Other Characteristics -Smooth, raised and translucent colonies -Facultative intracellular pathogens -Biosafety Practice Level 3

Brucella

Fastidious Gram Negative Bacilli Brucella Natural Host:Goat or sheep Serum Agglutination: + H2S (Lead Acetate): - Urease: V Thionine: - Fuchsin:-

B.melitensis

Fastidious Gram Negative Bacilli Brucella Natural Host:Cattle Serum Agglutination:+ H2S (Lead Acetate):+ Urease: +<2 hrs. Thionine: + Fuchsin:-

B. abortus

Fastidious Gram Negative Bacilli Brucella Natural Host:Swine Serum Agglutination:+ H2S (Lead Acetate):+ Urease: +<0.5 hrs. Thionine: - Fuchsin: +

B.suis

Fastidious Gram Negative Bacilli Brucella Natural Host:Dogs Serum Agglutination:- H2S (Lead Acetate):- Urease: +<0.5 hrs. Thionine: - Fuchsin:-

B. canis

Fastidious Gram Negative Bacilli Infections- zoonosis (ingestion, inhalation, arthropod bite), highly infectious -Tularemia (ulceroglandular, pneumonic, etc)-rabbit fever, water rat trappers disease Laboratory Diagnosis Microscopy -Small, non-motile, coccobacili or bacilli Culture and Other Characteristics -Strictly aerobic; require cysteine, cystine or thiosulfate (SBA, BCYE agar, CHOC) -Gray-white, smooth, raised colonies -Biosafety Practice Level 3

Francisella tularensis

Fastidious Gram Negative Bacilli Clinical Significance i. Virulence Factor a. Enter, survive and multiply within macrophages b. Survive and multiply within free-living protozoa c. Multiply at 20°C to 43°C and survive at 40°C to 60°C d. Capacity to adhere and persist in piped water systems Infections- Atypical pneumonia a. Legionnaire’s disease- fever w/ pneumonia (sporadic,epidemic,nosocomial) a. Pontiac Fever- fever w/o pneumonia

Legionella pneumophila

Fastidious Gram Negative Bacilli Epidemiology -Aquatic sources (lakes, rivers, hot springs and mud) -Man made distribution systems -Humidifiers and respiratory therapy equipment Specimen Collection and Handling -Respiratory secretion, body fluids, abscess, blood. Urine for Ag detection Microscopic Examination -Pleomorphic and weakly staining gram (-) bacilli -Direct immunofluorescent antibody test, Silver or Giemsa stains

Legionella pneumophila

Fastidious Gram Negative Bacilli Colony Morphology -Grayish-white or blue green, convex, and glistening measuring 2-4 mm in diameter -Characteristic "ground-glass" colony

Legionella pneumophila

Fastidious Gram Negative Bacilli Bordetella Virulence Factors facilitate attachment to ciliated epithelial cells.

FHA and Pertactin

Fastidious Gram Negative Bacilli Bordetella Virulence Factors interferes to signal transduction.

Pertussis toxin

Fastidious Gram Negative Bacilli Bordetella Virulence Factors inhibits host epithelial and immune effector cells.

Adenylate cyclase toxin

Fastidious Gram Negative Bacilli Bordetella Virulence Factors causes ciliostasis and DNA synthesis

Tracheal cytotoxin

Fastidious Gram Negative Bacilli Clinical Manifestations -Pertussis (whooping cough) -Catarrhal, Paroxysmal, Convalescent phase Epidemiology -Droplets or direct contact with secretions -Organism adhere and replicate on ciliated respiratory epithelial cells

Bordetella Bordetella pertussis and B. parapertussis

Fastidious Gram Negative Bacilli Microscopic and Colony morphology -Tiny gram-negative coccobacilli -Smooth, glistening and silver, resembling mercury droplets

Bordetella Bordetella pertussis and B. parapertussis

Fastidious Gram Negative Bacilli Bordetella Laboratory Diagnosis Charcoal-horse blood + (3-5 d) Blood agar - Mac/Catalase/Motility - Oxidase + Urease -

B. pertussis

Fastidious Gram Negative Bacilli Bordetella Laboratory Diagnosis Charcoal-horse blood + (2-3 d) Blood agar + Mac/Catalase/Motility - Oxidase - Urease + 24 hours

B. parapertussis

Fastidious Gram Negative Bacilli Bordetella Laboratory Diagnosis Charcoal-horse blood + (1-2 d) Blood agar + Mac/Catalase/Motility + Oxidase + Urease + 4 hours

B. bronchiseptica

SEMR: Gram (-) bacilli Flashcards

(132 cards)