Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
221 Cards in this Set
- Front
- Back
|
GPB Spore-forming Catalase positive Non-hemolytic Nonmotile Penicillin sensitive |
Bacillus anthracis |
|
|
What organism is the etiologic agent of anthrax? |
B. anthracis |
|
|
What is the spore stain? |
Primary stain: Malachite green Counterstain: Safranin Malachite green is driven into cells with heat (doesn't adhere well to cell wall) Malachite green rinses easily from vegetative cells |
|
|
What is PEA? |
Phenylethyl alcohol agar For GP |
|
|
Most Bacillus species are: |
Beta-hemolytic Motile |
|
|
How are humans generally infected with Bacillus anthracis? |
As a result of contact with animals or animal products |
|
|
What are the three types of anthrax? |
Cutaneous anthrax- site of spore penetration Pulmonary anthrax- inhalation of spores Gastrointestinal anthrax- ingestion of spores |
|
|
What organism has filamentous projections, "Medusa head" on SBA with consistency of beaten egg whites? |
Bacillus anthracis |
|
|
What organism has large, square-ended GP, "bamboo" rods? |
Bacillus anthracis |
|
|
What is the clinical significance of Bacillus cereus? |
Food poisoning -Diarrheal type: watery diarrhea caused by enterotoxin -Emetic type: vomiting caused by emetic toxin Serious infection |
|
|
What are the virulence factors of Bacillus anthracis? |
Anti-phagocytic capsule Exotoxin for cell and tissue destruction |
|
|
A suspected infection of B. cereus needs to be worked up from the contaminated food, not the stool because... |
B. cereus is a part of the stool normal flora |
|
|
Normal stool flora Large GP rods w/spores beta-hemolytic Motile Penicillin-resistant |
Bacillus cereus |
|
|
Think cheese think... |
Listeria monocytogenes (also found in soil, vegetation, other animal products |
|
|
What are the clinical infections of Listeria monocytogenes? |
Most common: infections is newborns and immunocompromised adults (bacteremia, meningitis)
-Congenital (usually results in still birth, if born usually results in sepsis or meningitis) -Gastroenteritis in healthy folks (food poisoning) |
|
|
What GP organism has colony morphology that resembles S. agalactiaea? |
L. monocytogenes |
|
|
Facultative Beta-hemolytic GP small rod (almost coccal) Non-sporulating Catalase + Tumbling motility + Esculin hydrolysis + Sodium hippurate hydrolysis + CAMP + (shovel, wedge) Glucose F |
Listeria monocytogenes |
|
|
What organism has cold enrichment and will grow at 4C? |
Listeria monocytogenes |
|
|
"Diptheroids" are... And where are they found? |
Corynebacterium sp. Found widely distributed in nature, many species are part of normal flora |
|
|
GP, club-shaped, pleomorphic rods Beta-hemolytic small zone Non-spore forming Catalase + Glucose F Sucrose = Urease = Nitrate reduction variable Toxin production |
Corynebacterium diptheriae |
|
|
GP, club-shaped, pleomorphic, palisading rods Non-hemolytic Non-spore forming Catalase + Glucose O Sucrose = Urease = Nitrate reduction = |
Corynebacterium jeikium |
|
|
What organism is commonly a urinary tract pathogen seen in long-term hospitalized, older patients who are immunocompromised and catheterized? |
Corynebacterium urealyticum |
|
|
Diptheria is... |
A disease of the respiratory tract Pseudomembrane should be cultured |
|
|
What is the pathogenesis of Corynebacterium dptheriae and what usually leads to death of infected individuals? |
Found primarily on epithelial cells of respiratory tract of persons with disease or carriers
Infection occurs by droplets or contact Produces exotoxin that causes necrosis- forms grayish pseudomemebrane (WBC and organism) Death usually occurs by congestive heart failure |
|
|
What is Loeffler's media used for? |
Good for C. diptheriae Produce metachromatic granules when grown on this media |
|
|
What is Tinsdale agar CTBA good for? |
Good for C. diptheriae- can be differentiated by brown halo around colony Tellurite is reduced to metallic tellurium by Corynebacterium species forming gray-black colonies |
|
|
Definitive identification of C. diptheriae requires what? |
Demonstration of toxin production by the isolate Perform toxigenicity tests -Elek test -PCR (will tell you if organism has toxin gene not expression) -ELISA |
|
|
C. jeikeium infects... And causes... |
Immunocompromised patients
IV drug users Septicemia Meningitis Pulmonary disease |
|
|
Corynebacterium jeikeium and C. urealyticum are susceptible to... |
Vancomycin |
|
|
GP, long filamentous rods Non-sporulating Non- or alpha-hemolytic Microaerophilic Catalase = Nonmotile H2S + |
Erysipelothrix rhusiopathiae (will show "test tube brush" growth pattern in semi-solid motility media |
|
|
What organism is the only GPR that is H2S+? |
Erysipelothrix rhusiopathiae |
|
|
Turkeys and swine= |
Erysipelothrix rhusiopathiae |
|
|
GP, long slender rods or curly Q's Non-sporulating Alpha-hemolytic (sometimes gamma) Microaerophilic Catalase = H2S = Resistant to vancomycin |
Lactobacillus sp. |
|
|
Lactobacillus sp. are found... |
Normal flora Rarely pathogenic |
|
|
What organism is best isolated on human blood agar? |
Gardnerella vaginalis |
|
|
GP, pleomorphic rods Non-sporulating Clue cells Catalase = Sodium hippurate + Hydrolyzes starch Beta-hemolytic with human RBCs |
Gardnerella vaginalis |
|
|
What are clue cells? |
Vaginal epithelial cells coated with bacteria giving distinctive stippled appearance Gardnerella vaginalis |
|
|
What organism may pit the agar and produce a black dot on the agar under the colony? |
Arcanobacterium sp. (A. haemolyticum) |
|
|
GP, pleomorphic, slight branching rods Non-sporulating Beta-hemolytic (small zones) Catalase = Reverse CAMP + PYR + (some strains) |
Arcanobacterium sp. (A. haemolyticum) |
|
|
Why is Reverse CAMP + for Arcanobacterium haemolyticum? |
Because of phospholipase D production that inhibits beta lysin of S. aureus |
|
|
GP, pleomorphic, slight branching rods Non-sporulating Beta-hemolytic (small zones) Catalase = Reverse CAMP = |
Arcanobacterium pyogenes |
|
|
GP, pleomorphic, branching rods (beaded look) Non-sporulating Aerobic 3-30 days Chalky, wrinkled Partially acid-fast + Catalase + Lysozyme resistance + |
Nocardia sp. (N. asteroides and N. braziliensis) |
|
|
Arcanobacterium haemolyticum causes... Arcanobacterium pyogenes causes... |
A. haemolyticum causes pharyngitis in kids A. pyogenes is an animal pathogen that causes bacteremia, skin infections, otitis media... |
|
|
What do Nocardia sp. cause? |
Cutaneous infections usually a result of traumatic injury N. brasiliensis causes 80% of cutaneous infections Pulmonary infections typically caused by N. asteroides in immunocompromised patients |
|
|
GP rods with extensive branching Non-sporulating Aerobic 3-30 days Chalky, wrinkled Partially acid-fast = Catalase + Lysozyme resistance = |
Streptomyces sp. |
|
|
GP, diptheroid rods, filaments, branching Non-sporulating Non-hemolytic 3-14 days Mucoid and salmon pink Carbohydrate utilization = Partially acid-fast + |
Rhodococcus equi Typically pulmonary infections in immunocompromised individuals |
|
|
Most are normal flora of stool... |
Enterobacteriaceae |
|
|
Enterobacteriaceae are... |
Fermenters Oxidase = Grow on MAC |
|
|
What are the most commonly encountered GNBs in clinical specimens? |
Enterics |
|
|
Enterics are divided into two categories... |
Opportunistic pathogens Primary Intestinal pathogens (not commensal flora) |
|
|
True or False: Colony morphology on primary isolation media is a useful tool in identifying Enterobacteriaceae. |
False In general, colony morphology is large, gray, smooth, beta- or non-hemolytic |
|
|
In stool cultures, BA is mainly used for... |
Looking for an imbalance in GN to GP/yeast organisms (should mostly be GN- normal flora) |
|
|
NLF GN colonies on MAC are... |
possibly Salmonella or Shigella organisms LF colonies and LF colonies precipitating bile salts are normal flora |
|
|
What is EMB? |
Eosin-methylene blue Selective differential Allows most GN to grow Metallic green = lactose + |
|
|
What is SS? |
Selective for Salmonella-Shigella agar Contains Lactose, Sodium thiosulfate Stool cultures: Pink/red= normal flora Colorless w/out black center: possibly Shigella or Salmonella Colorless w/black center: possibly Salmonella |
|
|
What is HE |
Hektoen enteric Selective for Salmonella and Shigella Contains Bile salts, lactose, bromothymol blue, sodium thiosulfate (H2S) |
|
|
NF on HE think... |
Salmonella or Shigella |
|
|
What is XLD? |
Xylose, lysine, deoxycholate Selective for Salmonella and Shigella A little better for Shigella Contains sodium deoxycholate, lactose, sucrose, phenol red, lysine for DC detection Yellow= F, LDC=red |
|
|
What is CIN agar? |
Cefsulodin-inrgasan-novobiocin Selective differential for Yersinia enterolitica "Bull's eye" colonies mannitol is differentiating agent |
|
|
TSI: K/K= K/A= K/A w/H2S= A/A= |
TSI: K/K= NF K/A= Glucose F K/A w/H2S= Glucose F with H2S A/A= Glucose + Lactose + Sucrose F or Glucose + Sucrose F or Glucose + Lactose F |
|
|
What is ONPG? |
Detects beta-galactosidase activity Helpful in identifying slow lactose fermenters deficient in permease enzyme (NOTE-all lactose fermenters with the permease enzyme will also be ONPG+) |
|
|
What does Indole test for and what is the Indole tube and spot interpretation: |
Looking for production of tryptophan if organism produces tryptophanase Tube: Red + Orange/no red = Spot: Blue + No color change = |
|
|
What is MR-VP and what is the interpretation? |
Glucose fermentation in one of two pathways. MR: Red+, not red= VP: Red+, not red= |
|
|
What is DNase and what is useful for? |
Looking for presence of DNase Very useful in the identification of genus Serratia |
|
|
What are the three types of antigenic determinants for Enterobacteriaceae? |
O (somatic antigen) cell wall- heat stable used to organize organisms in genus K (capsular antigen) covers O ag- heat labile not all have K (E. coli, Klebsiella, Salmonella) H (flagellar antigen) heat labile used to serotype within species |
|
|
What are the 7 tribes of Enterobacteriaceae? |
Escherichieae Salmonelleae Klebsielleae Citrobacteriaceae Proteeae Yersinieae Edwardsielleae |
|
|
What organism can be biochemically mistaken for Shigella? |
E. coli |
|
|
Phenylalanine Deaminase (PAD) + |
Tribe Proteeae |
|
|
What is the mostcommon cause of UTI and kidney infection inhumans as well as the mostcommon causes of septicemia and meningitis among neonates? |
E. coli |
|
|
What is EHEC? |
Enterohemorrhagic E. coli ProducesShiga toxin/verotoxin E. coliO157:H7 and others Toxins cause inflammatory response, bloody diarrhea, no WBC in stool, associated with HUS |
|
|
How can you differentiate E. coli O157:H7 from other strains? |
Sorbitol utilization = (SMAC) All other strains can utilize |
|
|
E. coli Colony morphology: EMB MAC |
EMB: metallic green sheen MAC: dark pink with pink diffusion (strong LF) |
|
|
What is EPEC? |
Enteropathogenic E. coli primarily in infants and children outbreaks in hospital nurseries Diarrhea with mucous but not bloody |
|
|
What is ETEC? |
Enterotoxigenic E. coli “traveler’s diarrhea” watery diarrhea without blood self-limiting, usually not identified |
|
|
What is EIEC? |
Enteroinvasive E. coli produce dysentery with bowel penetration, invasion and destruction ofintestinal mucosa watery diarrheawith blood do NOT ferment lactose |
|
|
What is EAEC? |
Enteroaggregative E. coli Cause diarrhea byadhering to the mucosal surface of the intestine watery diarrhea |
|
|
What is DAEC? |
Diffusely adherent E. coli Associated with UTI’s anddiarrhealdisease, esp. in children and pregnant women |
|
|
MAC pink LF; EMB green sheen Oxidase = KIA A/A w/gas H2S = Indole + Citrate = MR + VP = Lysine + Motility + |
E. coli |
|
|
What are the genera of Tribe Escherichieae? |
Escherichia Shigella |
|
|
What genus causes dysentery and transmission only occurs human to human (humans only known reservoir)? |
Shigella |
|
|
What are the four species (serotypes) of Shigella that cause dysentery? |
Shigella dysenteriae -Group A (most severe) Shigella flexneri -Group B Shigella boydii - Group C Shigella sonnei - Group D (leastsevere) |
|
|
Dirty Fingers Bring Shigella |
S. dysenteriae A S. flexneri B S. boydii C S. sonnei D |
|
|
MAC NLF HE Green XLD Red Oxidase = KIA K/A H2S = ONPG = LDC = ODC = Nonmotile |
Shigella sp. subgroups A, B, C |
|
|
MAC NLF HE Green XLD Red Oxidase = KIA K/A H2S = ONPG + LDC = ODC + Nonmotile |
Shigella sonnei |
|
|
All Shigella isolates must be... |
serotyped Based on O antigen to divide into serotypes If organism shows no agglutination, must be heated and retested (to destroy K ag) |
|
|
What are the genera in the Tribe Salmonelleae? |
Salmonella |
|
|
What infections result from Salmonella? |
varying degrees of gastroenteritis and enteric fever Most commonly caused by contaminated food |
|
|
What is Enteric fever? |
Typhoid fever (only infects humans) Lymphatic system to blood to gall bladder to GI Caused by Salmonella serotype Typhi (Also paratyphoid fever-milder disease caused by Salmonella serotype Paratyphi) |
|
|
What is the most pathogenic of Salmonella sp? |
Salmonella serotype Typhi (S. enterica subgroup 1 serotype) |
|
|
Oxidase = KIA K/A w/H2S LDC + ODC + Indole = Citrate + (95%) |
Salmonella sp. (enterica) |
|
|
Oxidase = KIA K/A w/trace H2S LDC + ODC = Indole = Citrate = |
Salmonella Typhi |
|
|
Oxidase = KIA K/A w/H2S (10%) LDC = ODC + Indole = Citrate = |
Salmonella Paratyphi |
|
|
All Salmonella isolates must be... |
Serotyped Screen with 2 polyvalent antisera ID with monovalent antisera (Most concerned about if it has D antigen) |
|
|
What are the genera in the Tribe Klebsielleae? |
Serratia Klebsiella Enterobacter Hafnia |
|
|
Tribe Klebsielleae primarily cause... |
Pneumonia (also wound and UTI) |
|
|
Oxidase = KIA K/A H2S =; TSI A/A H2S = LDC + ODC + ONPG + Indole = Citrate + VP + DNase + Gelatinase + |
Genus Serratia |
|
|
Serratia marcescens will appear ________ on MAC |
Red
BUT not a lactose F Organism produces red pigment |
|
|
Sputum red "currant jelly-like" and patient has destructive pneumonia with necrosis |
Klebsiella pneumoniae |
|
|
Mucoid colonies BA Oxidase = KIA A/A w/gas H2S = LDC + Indole = Citrate + Nonmotile VP + |
Klebsiella pneumoniae |
|
|
Oxidase = KIA A/A w/gas H2S = LDC + Indole + Citrate + Nonmotile VP + |
Klebsiella oxytoca |
|
|
Oxidase = KIA A/A w/gas H2S = LDC = ODC + Indole = Citrate + MR = VP + |
Enterobacter cloacae |
|
|
Oxidase = KIA A/A w/gas H2S = LDC + ODC + Indole = Citrate + MR = VP + |
Enterobacter aerogenes |
|
|
What is the major characteristic of Hafnia alvei? |
Delayed citrate reaction |
|
|
Oxidase = KIA K/A or A/A (75%) H2S + (78%) LDC = ODC = Indole = (60%) Citrate + (78%) |
Citrobacter freundii |
|
|
Oxidase = KIA K/A or A/A (50%) H2S = LDC = ODC + Indole + Citrate + |
Citrobacter koseri |
|
|
What sets Tribe Proteeae apart? |
All normal flora Deaminate Phenylalanine and Tryptophan (PAD +) All are lactose = |
|
|
What enteric has swarming motility on BAP? |
Genus Proteus |
|
|
What genera are of the Tribe Proteeae? |
Proteus Providencia Morganella |
|
|
Oxidase = KIA K/A H2S + TSI K/A H2S + ODC + Indole = Urea ++ |
Proteus mirabilis |
|
|
Oxidase = KIA K/A H2S + TSI A/A H2S + ODC = Indole + Urea ++ |
Proteus vulgaris |
|
|
Providencia rettgeri is a pathogen of... Providencia stuartii can cause... |
Providencia rettgeri is a pathogen of urinary tract. Providencia stuartii can cause nosocomial outbreaks in burn units |
|
|
What can help differentiate Providencia sp.? |
Citrate + |
|
|
Oxidase = KIA K/A H2S = ODC = Indole + Urea + Citrate + |
Providencia sp. (Note: P. stuartii can be urea =) |
|
|
Oxidase = KIA K/A H2S = ODC + Indole + Urea + |
Morganella morganii |
|
|
What is the causative organism of the plague? |
Yersinia pestis |
|
|
What are the three forms of the plague? |
Bubonic- painful inflammatory swelling of lymph node Pneumonic- 2ary to bubonic- in blood, respiratory tract (can be transmitted person to person) Septicemic- blood infection w/out buboes Vector is rat flea and human is accidental host |
|
|
Yersinia enterocolitica mainly causes... |
Acute gastroenteritis Most common form of Yersinia |
|
|
How is Yersinia enterocolitica similar to Listeria? |
Can use cold enrichment to isolate because it can survive refrigerator temps |
|
|
GN coccobacilli, bipolar staining "safety pin" with Wayson's stain |
Yersinia sp. |
|
|
Oxidase = KIA K/A (orange delayed GF) H2S = ONPG + (slow) ODC = Urea = Nonmotile |
Yersinia pestis |
|
|
Oxidase =
KIA K/A (orange delayed GF) H2S = ONPG + (slow) ODC + Urea + (75%) Rapid Motile RT Nonmotile 37C |
Yersinia enterocolitica |
|
|
Oxidase = KIA K/A H2S + Indole + Citrate = Urea = LDC + |
Edwardsiella tarda |
|
|
WHat is IMViC? |
Indole Methyl Red VP Citrate |
|
|
IMViC + + = = |
E. coli |
|
|
IMViC = = + + |
Klebsiella pneumoniae (also Enterobacter) |
|
|
(GN, Oxidase =) Lactose F think... |
E. coli Klebsiella Enterobacter (possibly Citrobacter) |
|
|
(GN, Oxidase =) Lactose F with mucoid colonies think... |
Klebsiella Enterobacter |
|
|
(GN, Oxidase =) H2S + think... |
Proteus sp. Salmonella sp. Citrobacter freundii possibly Edwardsiella tarda |
|
|
(GN, Oxidase =) Nonmotile think... |
Klebsiella Shigella Yersinia enterocolitica at 35C |
|
|
(GN, Oxidase =) Deamination (PAD/TDA) + think... |
Proteus Providencia Morganella |
|
|
(GN, Oxidase =) VP + think... |
Klebsiella Enterobacter Serratia |
|
|
(GN, Oxidase =) DNase + think... |
Serratia |
|
|
(GN, Oxidase =) Gelatinase + think... |
Serratia |
|
|
What are the types of infections associated with Aerobic NF GNB? |
Predominantly Opportunistic Septicemia Meningitis Osteomyelitis Wound infections following surgery/trauma Nosocomial infections |
|
|
What organisms are somewhat resistant to disinfectants and antibiotics? |
Aerobic NF GNB |
|
|
What is genus specific and also used for identification of Aerobic NF GNB? |
Growth on MAC |
|
|
How are NF GNB distinguished from Enterobacteriaceae? |
Utilization of glucose NF oxidize glucose rather than ferment |
|
|
What are some preliminary clues that an organism is a NF? |
-Long, thin GN rods or coccobacilli -Oxidase + (not all NF) -NG or slow growth on MAC -TSI nonreactive (K/K) -Resistant to antibiotics |
|
|
Differentiation of NF begins with... Then the next step would be... |
Initial breakdown: -O/F -growth on MAC -Oxidase Next Step: Based on above grouping, use specific set of differential media to ID (speciation can be difficult) |
|
|
What is Hugh-Leifson's O/F? |
Protein to Carbohydrate ratio of 1:5 (King's formulation is 2:1) Allows for better detection of carbohydrate utilization acid end products by decreasing formation of oxidative products Uses bromothymol blue pH indicator |
|
|
What are the interpretations for Hugh-Leifson's O/F? |
Both tubes yellow: facultative Open yellow, closed green: oxidative Both tubes green: assaccharolytic |
|
|
Most Enterobacteriaceae have flagella. What type? |
Peritrichous flagella (coming from all sides) |
|
|
What motility test is most accurate for Aerobic NF GNB and why? |
Hanging drop motility because some NF have polar flagella and they need oxygen to grow |
|
|
What is the acetamide test and what is the interpretation? |
Determines is organism can utilize acetamide as sole carbon source Blue + No color change = |
|
|
Smells of green apples... |
Alcaligenes faecalis |
|
|
Smells of grapes and Fritos...
|
Pseudomonas aeruginosa |
|
|
What is the most commonly isolated NF GNB? |
Pseudomonas |
|
|
One of the leading causes of hospital acquired infections is... |
Pseudomonas aeruginosa |
|
|
Aerobic GNB Oxidase + Indole = MAC growth Glucose, xylose Oxidizer Acetamide + Growth at 42C Arginine dihydrolase + Nitrate + |
Pseudomonas aeruginosa |
|
|
Pseudomonas aeruginosa may be mucoid on BA if... |
Mucoid if producing alginate Cystic fibrosis |
|
|
BA: Flat, gray green with metallic sheen, beta-hemolytic, grape-like odor |
Pseudomonas aeruginosa |
|
|
Pseudomonas aeruginosa is the only GN NF that produces... |
Pyocyanin (blue-green pigment) |
|
|
What agar can be used to detect pyocyanin and pyoverdin? |
Cetrimide agar |
|
|
Pyocyanin + pyoverdin = |
characteristic green that fluoresces under UV light |
|
|
What are the virulence factors of Pseudomonas aeruginosa? |
-Pili (attachment to cell surface) -Lipopolysaccharide (endotoxin) -Exotoxin A (inhibits protein synthesis) -Proteolytic enzymes -Extracellular alginate slime (inhibits phagocytosis especially in CF pts) -Intrisic antimicrobial resistance |
|
|
A blue-green pus in wound infection is seen with... |
Pseudomonas aeruginosa |
|
|
What types of patients are often infected by Pseudomonas aeruginosa? |
-Leukocytopenic -CF patients -Immunosuppressed -Extensive burns -IV drug abuser |
|
|
What are the other fluorescent pseudomonads? |
Pseudomonas fluorescens Pseudomonas putida |
|
|
How can you differentiate Pseudomonas fluorescens and putida from Pseudomonas aeruginosa? |
Fail to grow at 42C Acetamide = Nitrate = NO pyocyanin |
|
|
How can you differentiate Pseudomonas fluorescens from Pseudomonas putida? |
Both: non-hemolytic, best growth at 25-30C, pyoverdin pigment only Pseudomonas fluorescens: gelatin + Pseudomonas putida: gelatin = |
|
|
Non-fluorescent Pseudomonad is... |
Pseudomonas stutzeri |
|
|
Pseudomonas stutzeri colony morphology resembles what organism, what does it look like, and why is this significant? |
Resembles Burkholderia pseudomallei Wrinkled, adherent, leathery, hard, dry, yellow Significant because this organism is a potential bioterrorism agent |
|
|
How do you differentiate Pseudomonas stutzeri from other Pseudomonads? |
Arginine dihydrolase = (most others +) No fluorescent pigment Oxidizes maltose (most others can't) |
|
|
What is the clinical significance of Burkholderia pseudomallei? |
Causes meliodosis (aggressive granulomatous pulmonary infection) Acquired by ingestion, inhalation, or inoculation Classified as potential bioterrorist agent |
|
|
GNR bi-polar staining BAP smooth mucoid turns dry wrinkled MAC NLF Oxidizer + Oxidase + Earthy smell |
Burkholderia pseudomallei |
|
|
Burkholderia pseudomallei must be differentiated from Pseudomonas stutzeri using what tests? |
Lactose oxidation and Arginine dihydrolase Burkholderia pseudomallei: lactose oxidizer and arginine dihydrolase + Pseudomonoas stutzeri: Lactose oxidizer = and arginine dihydrolase = |
|
|
What organism is second to Pseudomonas aeruginosa in isolation form CF patients? |
Burkholderia cepacia complex |
|
|
What is the BAP colony morphology for Burkholderia cepacia complex? |
Smooth, mucoid, strong earthy odor, usually non-pigmented but may produce bright yellow on iron containing media.
|
|
|
What is BCSA and OFPBL and what are they used for? |
-Burkholderia cepacia selective agar -Oxidative, fermentative, polymixin B, bacitracin, lactose agar Used for CF patient respiratory specimens |
|
|
NF GNR MAC growth + Oxidase + (weak, slow) Growth at 42C variable Oxidizer (glucose, lactose, maltose) LDC (Moeller based) + Polymyxin B resistant |
Burkholderia cepacia complex |
|
|
What two organisms are LDC (Moeller based) +? |
Burkholderia cepacia complex Stenotrophomonas maltophilia |
|
|
What is the clinical significance of Burkholderia mallei? |
Causes glanders A zoonosis fo donkeys, horses, mules Rare in humans Considered potential bioterrorist agent |
|
|
NF GN coccobacillus BAP nondescript MAC growth variable Oxidase variable Oxidizes glucose Nitrate + Arginine dihydrolase + Nonmotile |
Burkholderia mallei |
|
|
Elizabethkingia meningosepticum was formerly known as... |
Chryseobacterium meningosepticum |
|
|
What is the clinical significance of Elizabethkingia meningosepticum? |
Neonatal meningitis and sepsis (Nursery epidemics) |
|
|
NF thin GNR with swollen ends BAP smooth, large, pale yellow MAC growth variable/= Oxidase + Nonmotile Glucose oxidizer delayed Indole + |
Elizabethkingia meningosepticum |
|
|
What organism is the third most commonly encountered NF in clinical specimens? |
Stenotrophomonas maltophilia |
|
|
What types of infections are caused by Stenotrophomonas maltophilia? |
Pneumonia UTIs Wound infections Bacteremia (often catheter related) |
|
|
BA: Smooth, shiny, pale yellow-lavender green, smells of ammonia |
Stenotrophomonas maltophilia |
|
|
NF GNB Oxidase = Glucose oxidizer weak Growth at 42C = Maltose oxidizer strong LDC (Moeller based) + DNase + |
Stenotrophomonas maltophilia |
|
|
What genus is the second most commonly encountered NF in clinical specimens? |
Acinetobacter sp. |
|
|
NF GN plump coccobacilli (diplococci) BAP translucent to opaque never pigmented MAC colorless to slightly pink/purplish Oxidase = Nonmotile Glucose oxidizer |
Acinetobacter baumannii |
|
|
NF GN plump coccobacilli (diplococci) BAP translucent to opaque never pigmented MAC colorless to slightly pink/purplish Oxidase = Nonmotile Assaccharolytic |
Acinetobacter lwoffii |
|
|
The species A. baumannii and A. lwoffii are the most frequently Acinetobacter species isolated. How do you tell them apart? |
Glucose oxidation Acinetobacter lwoffii: Assaccharolytic Acinetobacter baumannii: Glucose oxidizer |
|
|
What organsims are bichemically inert and so what characteristic can you use to differentiate them? |
Alcaligenes/Achromobacter Alcaligenes Xylose oxidizer = Achromobacter Xylose oxidizer + (strong) |
|
|
What is the clinical significance of Alcaligenes/Achromobacter? |
Alcaligenes faecalis: opportunistic pathogen Achromobacter xylosoxidans: nosocomial septicemia and severe pulmonary symptoms in CF and intubated children |
|
|
GNB or coccobacilli
Oxidase + Motile Growth on MAC Glucose oxidizer (weak or assaccharolytic) LDC = |
Alcaligenes/Achromobacter |
|
|
NF GN plump coccobacilli BAP tiny pinpoint MAC slow or NG Oxidase + Nonmotile Assaccharolytic Highly susceptible to penicillin |
Moraxella (except catarrhalis) |
|
|
What organism must you check for beta-lactamase production? |
Moraxella (except catarrhalis) |
|
|
Almost all species of __________ are pathogenic for humans. |
Vibrio sp. |
|
|
What are the four major Vibrio species that might be found in the clinical lab? |
V. cholerae
V. parahaemolyticus V. vulnificus V. alginolyticus |
|
|
Which Vibrio species are halophilic? |
V. parahaemolyticus V. vulnificus V. alginolyticus |
|
|
What are characteristic common among Vibrio, Aeromonas, Plesiomonas, Campylobacter, Helicobacter, and Chromobacterium sp. |
Facultative GNR Glucose F Oxidase + Polar flagella if motile |
|
|
What is TCBS? |
Thiosulfate citrate bile salts sucrose Selective differential for GN Enhances growth of Vibrio Differential color reaction for Sucrose Yellow = sucrose + |
|
|
Curved GNB BAP beta-hemolytic MAC NLF TCBS yellow = Sucrose F Growth in 0% NaCl Motile Oxidase + Nitrate + |
Vibrio cholerae |
|
|
What are the two major biotypes of Cholera? |
O1 classic El Tor |
|
|
What is cholera? |
Enterotoxin production "cholera toxin" affects absorptive ability of GI Rice water stools 10-30/day with mucous Dehydration, hypovolemic shock Human is only host |
|
|
Curved GNB BAP beta-hemolytic, MAC NLF TCBS green = Sucrose NF ODC + LDC + Indole + Growth in 6% NaCl Motile Oxidase + Nitrate + |
Vibrio parahaemolyticus |
|
|
What disease states are associated with Vibrio parahaemolyticus? |
Gastrointestinal diseas - more self-limiting
Common in Japan Raw or improperly cooked seafood |
|
|
Curved GNB BAP Non-hemolytic, MAC LF TCBS green = Sucrose NF ODC variable LDC + Indole + Growth in 6% NaCl Motile Oxidase + Nitrate + |
Vibrio vulnificus |
|
|
What organism is associated with history of traumatic aquatic wound? |
Vibrio vulnificus |
|
|
Curved GNB BAP beta-hemolytic, MAC NLF TCBS yellow = Sucrose F LDC + Indole + Growth in 6% NaCl Motile Oxidase + Nitrate + |
Vibrio alginolyticus |
|
|
Straight GNB SBA beta-hemolytic, MAC NLF or LF CIN pink colonies Sucrose F Inositol NF LDC + ADH + ODC = Indole + Growth in 0% NaCl Esculin +, Gelatin +, DNase + |
Aeromonas hydrophila |
|
|
What organism is isolated form retail produce and animal meat products?
|
Aeromonas hydrophila |
|
|
How does Plesiomonas shigelloides stand out from Aeromonas? |
Decarboxylation/dihydrolase (LDC, ADH, ODC +) AND Esculin, gelatin, DNase (all =) |
|
|
Pleomorphic GNR SBA Non-hemolytic shiny opaque Lactose variable, delayed F Sucrose NF Inositol F LDC + ADH + ODC + Indole + Growth in 0% NaCl Esculin =, Gelatin =, DNase = |
Plesiomonas shigelloides |
|
|
What is the habitat for Aeromonas hydrophila? |
Water and sewage |
|
|
What is the habitat for Plesiomonas shigelloides? |
Fresh water in tropical areas |
|
|
Plesiomonas shares antigenic structures with... |
Shigella Less virulent though |
|
|
Slightly curved GNB Smells like almonds SBA and MAC violet pigment colonies Oxidase + Motile Indole = Glucose F Sucrose variable F |
Chromobacterum violaceum |
|
|
The violet pigment of _______________ can interfere with what reaction? How do you solve this problem? |
Violet pigment on Chromobacterum violaceum can interfere with oxidase reaction. You can grow the organism in an anaerobic environment to prevent pigment production |
|
|
What is the disease state associated with Chromobacterum violaceum? |
Opportunistic pathogen that attacks patients with neutrophil defects Skin lesion is the usual port of entry |
|
|
Campylobacter sp. are associated with what condition? |
Diarrhea and systemic infections |
|
|
Curved GNB "seagull wing" shape BAP gray/pink, moist, spreading MAC NG Grows best at 42C Darting motility Assaccharolytic Microaerophilic and Capnophilic Urease = |
Campylobacter jejuni |
|
|
Carbolfuschin may need to be used as counterstain for what organism and why? |
Campylobacter jejuni B/c stains poorly and carbolfuschin is a deeper red |
|
|
GNB "seagull wings" Oxidase + Catalase + Hippurate hydrolysis + Growth at 42C Nalidixic acid susceptible Cephalothin resistant Darting motility |
Campylobacter jejuni |
|
|
What is the leading cause of diarrhea worldwide? |
Campylobacter jejuni |
|
|
What is the main difference in differentiating Campylobacter species? |
Campylobacter jejuni is hippurate hydrolysis + and other species are negative |
|
|
Helicobacter pylori is associated with what cliniclal conditions? |
Gastric, peptic, and duodenal ulcers Produces low-grade inflammatory response which damages tissues resulting in ulcers |
|
|
What is the mechanism that H. pylori can survive in human stomachs?
|
Produces urease to breakdown urea to ammonia and neutralize stomach pH |
|
|
How do you test for H. pylori? |
Strongly urease positive Usually detected using non-culture methods and can be presumptively identified through gastric biopsy using Onto Christensen's urea medium (looking for rapid color change) |
