Chapter 20 (Campylobacter and Helicobacter) and Chapter 21 (Nonfermenters and Misfits)

Pseudomonas aeruginosa P. aeruginosa is the most commonly isolated species of the genus in clinical specimens. It is an uncommon part of the normal bacterial biota and is isolated from less than 12% of normal stool specimens. It may, however, account for 5% to 15% of all nosocomial infections, especially pneumonia and bacteremia.

What Pseudomonas sp. is the nonfermenter that is the leading cause of nosocomial pneumonia and bacteremia?

Oxidase Most nonfermentative gram-negative bacilli are oxidase-positive, a feature that differentiates them from the Enterobacteriaceae (except Plesiomonas, which is oxidase-positive).

What biochemical test will differentiate nonfermenters from Enterobacteriaceae (except Plesiomonas)?

B. mallei

What is the causative agent of glanders?

Erythromycin he drug of choice for treating intestinal campylobacteriosis is erythromycin, although most patients recover without antimicrobial intervention.

What is the drug of choice for treating intestinal campylobacteriosis?

Burkholderia cepacia

What nonfermenter may produce a weak, slow, positive oxidase reaction?

B. pseudomallei

What organism causes melioidosis?

Campylobacter

What organism has a microscopic morphology of tiny, curved, gram-negative rods, with S-shapes or seagull-wing shapes on Gram stain?

P. aeruginosa

What organism is a common cause of pulmonary disease among individuals with cystic fibrosis?

Chromobacterium violaceum

What organism is an opportunistic pathogen that strikes the immunocompromised patient with neutrophil deficits and produces a violet pigment on nonselective agar?

Burkholderia cepacia

What organism is associated with pneumonia in patients with cystic fibrosis or chronic granulomatous disease (CGD)?

Campylobacter

What organism may play a role in Guillain-Barré syndrome (GBS)?

Carbohydrates

What substances do nonfermenters fail to ferment in traditional media?

42° C

What temperature is an optimal growth temperature for Campylobacter jejuni?

Microaerophilic and capnophilic

What type of an atmosphere do campylobacters require for growth?

Cary-Blair

When collecting specimens that may contain Campylobacter spp. bacteria, what transport medium should they be placed in, if a delay in transport is possible?

Acinetobacter spp.

Which gram-negative coccobacilli can appear as gram-positive cocci in smears made from blood culture bottles?

Burkholderia mallei zoonosis glanders

Which nonfermenter is considered by government agencies to be a potential bioterrorist agent?

Alcaligenes faecalis Burkholderia cepacia Acinetobacter lwoffii Yersinia entercolitica ----- you don't belong here

Which of the following Gram negative bacteria ferments glucose?

Endotoxin Exotoxins Capsule All of the above----------- P. aeruginosa may produce a variety of factors that lend to its pathogenicity, such as endotoxin (lipopolysaccharides), motility, pili, capsule, and several exotoxins: proteases, hemolysins, lecithinase, elastase, and DNase. Despite a number of virulence factors, this bacterium is still considered an opportunistic pathogen.

Which of the following is a virulence factor of Pseudomonas aeruginosa?

Burkholderia cepacia

A 17 year old girl with cystic fibrosis is diagnosed with pneumonia. A sputum sample grew gram negative bacilli with yellow smooth colonies that have the following biochemical reactions: Oxidase: positive TSI: K/K glucose: oxidized fluorescence: negative lysine decarboxylase: positive The most likely organism is: Burkholderia cepacia Klebsiella pneumoniae Shewanella putrifaciens Stenotrophomonas maltophlia

Brucella agar base, 10% sheep red blood cells, vancomycin, trimethoprim, polymyxin B, amphotericin B, and cephalothin.

CAMPY-BAP (blood agar plate) contains

Hippurate hydrolysis positive

Campylobacter jejuni can be identified by its microscopic morphology, characteristic motility, oxidase positivity, and this.

Pseudomonas aeruginosa

Cetrimide agar is used as a selective isolation agar for which organism? Acinetobacter spp. Pseudomonas aeruginosa Moraxella spp. Stenotrophomonas maltophilia

weak fermenters. cause of nosocomial infections. ubiquitous in soil and water. All the above

Characteristics of most members of the family Flavobacteriaceae

Burkholderia cepacia

Colonies of this bacteria are nonwrinkled, and this trait may be used to differentiate isolates from P. stutzeri, which also produces a yellow pigment. It does not fluoresce like P. aeruginosa, but can produce a nonfluorescing yellow or green pigment that may diffuse into the media.

Campylobacter The typical colony morphology of Campylobacter jejuni and other enteric campylobacters is moist, "runny looking," and spreading. Colonies are usually nonhemolytic; some are round and raised, whereas others may be flat.

A Campy blood agar plate incubated at 42° C from a stool exhibits colonies that are nonhemolytic, moist, "runny looking," and spreading. The Gram stain shows tiny gram-negative rods with some S-shapes and seagull-wing shapes. What is growing on the plate?

growth at 42 degrees C

A characteristic that is helpful in separating Pseudomonas aeruginosa from other members of the Pseudomonas family is: a positive test for cytochrome oxidase oxidative metabolism of OF test production of fluoescein pigment growth at 42 degrees C

Burkholderia pseudomallei

A college student who recently studied a semester abroad in Southeast Asia is admitted to the hospital with a diagnosis of "glanders-like" infection (melioidosis) . A sputum specimen grows a small gram-negative rod that is positive for oxidase, reduces nitrate to gas and oxidizes glucose, lactose and mannitol. What is the most likely organism? Stenotrophomonas maltophilia Burkholderia pseudomallei Pseudomonas aeruginosa Acinetobacter baumannii

urea broth

A gastroenterologist submits a gastric biopsy from a patient with a peptic ulcer. To obtain presumptive evidence of Helicobacter pylori, a portion of the specimen should be added to which media? urea broth tetrathionate selenite tryptophan

Chromobacterium

A genus that is found in soil and water and causes infections in immunocompromised patients has the following characteristics: Sheep blood agar: Violet pigment MacConkey agar: growth Oxidase: positive OF glucose: fermenter indole: negative The genus is: Campylobacter Chromobacterium Aeromonas Serratia

Helicobacter pylori Keyword: gastric biopsy

A gram stain touch prep from a gastric biopsy shows gram negative bacilli that are slender and curved. The most likely pathogen is:

gastroenteritis

Elizabethkingae meningosepticum causes all the following diseases, except

Helicobacter pylori

Major cause of Type B gastritis and associated with gastric cancer

Chromobacterium violaceum

Fermentative, gram-negative bacillus that may be oxidase positive, so it may be mistaken initially as a nonfermenter in the laboratory. It is motile with polar flagella and, as its name implies, produces a violet pigment about 91% of the time.

indole-positive.

All of the following are characteristics of pseudomonads, except

Anemia Poor prognostic factors associated with P. aeruginosa bacteremia include septic shock, granulocytopenia, inappropriate antimicrobial therapy, and the presence of septic metastatic lesions.

All of the following are poor prognostic factors associated with Pseudomonas aeruginosa bacteremia, except

growth at 42 degrees C, pyocyanin production, gelatinase production

An organism has been identified as a member of the fluorescent group of Pseudomonas. Which of the following sets of tests should be used to determine the species of the organism?

Pseudomonas stutzeri Pseudomonas stutzeri typically produces a dry, wrinkled colony. The colony morphology resembles Burkholderia pseudomallei. This bacterium in not a common clinical isolate and is a rare pathogen.

An oxidase-positive, nonfermentative gram-negative bacillus that characteristically produces dry, wrinkled colonies describes

Burkholderia cepacia

Oxidative-fermentative base-polymyxin B-bacitracin-lactose (OFPBL) media is the best media to use to isolate which one of the following organisms from the sputa of patients with cystic fibrosis? A. delafieldii R. pickettii B. cepacia B. pseudomallei

Pyocyanin

Pseudomonas aeruginosa also produces this pigment in addition to pyoverdin

β-hemolysis

Pseudomonas aeruginosa displays what type of hemolysis

Fluoroquinolones

Pseudomonas aeruginosa is resistant to all the following antimicrobial agents, except

DNase

Stenotrophomonas maltophilia is positive for this test. Oxidase Lactose fermentation DNase None of the above

Acinetobacter spp

Strictly aerobic coccobacilli or even cocci. Oxidase NEGATIVE, nonmotile, purple hue.

Pseudomonas aeruginosa

The third most common cause of gram-negative bacillary bacteremia, after E. coli and Klebsiella pneumoniae

Pseudomonas aeruginosa. Acinetobacter spp. Stenotrophomonas maltophilia Pseudomonas putida -------------

The three nonfermenters that make up the majority of isolates routinely seen in clinical laboratories include all the following, except

Alcaligenes faecalis and Achromobacter spp

These 2 possess peritrichous flagella and are obligately aerobic, oxidase positive gram-negative bacilli.

Acineetobacter Steno malto Russell Crow Pseudomonas cepacia (slow weak positive) Pseudomonas luteola and P. oryzihabitans

These guys are Oxidase negative.

Moraxella spp

These weak ass species are susceptible to penicillin (an unusual characteristic for a nonfermenter), and are notably in the wrong ****ing chapter

Stenotrophomonas "Steno malto" maltophilia

Third most common nonfermentative, gram-negative bacillus isolated in the clinical laboratory. Nosocomial, Oxidase NEGATIVE, SXT drug of choice

Acinetobacter Iwoffi

This acinetobacter spp is asaccharolytic, and susceptible to almost all antimicrobials.

Acinetobacter baumannii

This acinetobacter spp is saccharolytic, and is resistant to many antimicrobials.

Skirrow agar

This agar is selective for H. pylori

Pseudomonas aeruginosa S. aureus smells like an old sock. P. mirabilis smells putrid. Nocardia sp. smells like a freshly plowed field.

This bacterium is said to have a fruity or grapelike smell.

Burkholderia "Are you not entertained" gladioli

This contrarian pathogen is negative for oxidase (some strains weakly positive), motile by means of one or two polar flagella and is catalase and urease positive, oxidizes glucose, is mannitol positive and decarboxylase negative, grows on MAC agar, and is 100% resistant to polymyxin B. Inhabits colosseums and likes swords.

Exotoxin A

This exotoxin of Pseudomonas aeruginosa functions similarly to diptheria toxin by blocking protein synthesis

Burkholderia mallei

This guy causes glanders, a super serious zoonotic disease that affects livestock. Considered a potential bioterrorism agent.

Burkholderia pseudomallei

This guy causes melioidosis, an aggressive pulmonary disease with metastatic abscesses in the lungs.

Pseudomonas aeruginosa

This pseudomonad likes to hang out at 42° C with campylobacter

Elizabethkingia meningoseptica

This species is in the running for having the dumbest name ever.

Burkholderia pseudomallei

This species should be suspected when a nonfermatative wrinkled colony with bipolar staining is isolated. Ashdown media is selective for this guy.

Growth at 35-37 degrees C Unlike jejuni

Which of the following results is typical of Campylobacter fetus subspecies fetus?

Burkholderia pseudomallei

Which organism exhibits bipolar staining on the Gram stain, which resembles a "safety-pin" appearance? B. mallei B. pseudomallei B. diminuta B. vesicularis

Acinetobacter spp.

Which organism may be mistaken for a lactose fermenter on MacConkey agar because of colonies exhibiting a purple hue on the media? Acinetobacter spp. P. luteola S. maltophilia Bordetella holmesii

Pseudomonas stutzeri

Who dis? Hint: its wrinkled

Acineetobacter

Who dis? Is that a purple hue? Neeto!

Pseudomonas aeruginosa

Who dis? Note the discoloration

Elizabethkingia meningoseptica

Who dis? Note the growth with yellow pigment on sheep blood agar (SBA) (left) and absence of growth on MacConkey plate (right)

Psychrobacter immobilis

psychrotropic, and the optimal temperature for growth is 20° C. They have been isolated from fish, processed meat, and poultry. Clinically, they have been isolated from the eye of a newborn, who had acquired the infection nosocomially via a water source.

P. aeruginosa Keywords: metallic sheen, grapelike odor, cetrimide agar

A microbiologist is reading the plates from a sputum culture. On the sheep blood agar (SBA), the microbiologist sees flat spreading colonies with a metallic sheen. On cetrimide agar, a fluorescent green color is seen in the medium with clear colonies. On MacConkey, medium clear colonies are seen that have a fruity or grapelike odor. What is the most likely organism?

Pseudomonas aeruginosa P. aeruginosa is a gram-negative rod that produces a green pigment and sometimes a metallic sheen on culture media. S. marcescens produces a brick-red pigment. C. violaceum produces a purple pigment. P. melaninogenica produces a brown-black pigment.

A microbiologist is reading the plates from a sputum culture. The culture is from a patient with cystic fibrosis. One organism dominates the blood agar, chocolate, and MacConkey plates. The MacConkey plate shows an organism with a green pigment and a metallic sheen. The probable identification for this organism is

will grow on MAC and EMB media Iwoffi dont give a **** he grow anywhere

Acinetobacter lwoffi differs from Neisseria gonorrhoeae in that Acinetobacter :

A rapid urease test done on a gastric biopsy H. pylori may be presumptively identified in a gastric biopsy specimen by testing for the presence of a rapid urease reaction. Urease activity may also be detected by the urea breath test.

How is Helicobacter pylori presumptively identified?

Nosocomial

In what single setting does Stenotrophomonas maltophilia typically produce disease?

Gastric, urea, breath test, Type B gastritis, 37° C

Keywords for Helicobacter pylori

aminoglycosides ---- This one ceftazidime. SXT. piperacillin

Members of the Alcaligenes are usually susceptible to all the following antimicrobial agents, except

Pyoverdin

Members of the Pseudomonas fluorescent group all produce this pigment

Pseudomonas.

Not including organisms in the Enterobacteriaceae family, the most common gram-negative bacilli encountered in clinical specimens are: Pseudomonas. Burkholderia. Ralstonia. Vibrio.