Fastidious and Unusual Gram Negative Bacilli (Part 1)

most haemophilus species are part of the normal _____ flora.

upper respiratory tract

list 3 haemophilus species exceptions that are not part of the normal upper respiratory tract flora.

haemophilus influenzae; haemophilus aegypticus, haemophilus ducreyi

haemophilus serotypes are based on the organism’s polysaccharide _____.

capsule

what are the 6 types of haemophilus serotypes?

a, b, c, d, e, f

what bacterial genus gram stain is described below:

• pleomorphic GNR

• coccobacillary (usually) → filamentous

• can stain faintly and be missed

haemophilus

acridine orange stain is more sensitive method for detecting _____ microscopically.

haemophilus

which haemophilus species does not require X factor or V factor or both?

haemophilus aphrophilus

which factor refers to “hemin”?

X factor

which factor refers to “nicotinamideadenine dinucleotide = NAD”?

V factor

factors X and V are found in ____.

RBCs

rabbit and horse blood agar supports the growth of haemophilus, but not _____ blood agar.

sheep

although haemophilus does not normally grow on sheep blood agar, if another organism is present that can supply factor V (NAD), V factor requiring haemophilus may grow as ____ colonies in the hemolytic zone of another organism.

satelliting

what agar contains both X and V factors?

CHOC

haemophilus is beta lactam _____.

resistant

which haemophilus is considered the most invasive?

haemophilus influenzae type b (Hib)

haemophilus biogroup aegypticus causes what condition?

pink eye

which bacteria was the leading cause of invasive disease (meningitis and bacteremia) in children <2 years?

haemophilus influenzae type b (Hib)

a vaccine (conjugate) dramatically reduced cases of haemophils influenzae type b (Hib) in the US. true or false?

true

which bacteria was linked to brazilian purpuric fever outbreaks in the 1980s?

haemophilus influenzae biogroup aegypticus

which bacteria may cause an STD that causes a chancroid or “soft chancre”?

haemophilus ducreyi

what bacteria causes the following symptoms:

• painful genital ulcers

• buboes (swollen lymph nodes containing pus) in the groin

haemophilus ducreyi

what bacteria often goes missed/misdiagnosed due to the similarities to herpes and syphilis?

haemophilus ducreyi

what bacteria’s gram stain and colonies characteristics best fit the following information:

• colony: dome shaped and adherent

• gram stain: groups of GNR

  • “school of fish” or “railroad tracks”

haemophilus ducreyi

other haemophilus species are usually nonpathogenic, but they are opportunistic pathogens and are associated with what condition?

endocarditis

which members of the HACEK group are associated with slowly progressive (subacute) bacterial endocarditis?

haemophilus

which haemophilus species is associated with the following results:

• requires X factor

• requires V factor

• no hemolysis

haemophilus influenzae

which haemophilus species is associated with the following results:

• does not require X factor

• requires V factor

• no hemolysis

haemophilus parainfluenzae

which haemophilus species is associated with the following results:

• requires X factor

• requires V factor

• hemolytic

haemophilus haemolyticus

which haemophilus species is associated with the following results:

• does not require X factor

• requires V factor

• hemolytic

haemophilus parahaemolyticus

which haemophilus species is associated with the following results:

• variable requirements for X factor

• does not require V factor

• no hemolysis

haemophilus aphrophilus

which haemophilus species is associated with the following results:

• requires X factor

• does not require V factor

• no hemolysis

haemophilus ducreyi

the following information describes _____

• each section of a mueller hinton contains a different additive

  • horse blood: determines hemolytic activity

  • X factor (hemin) only

  • V factor only (NAD)

  • X and V factor

quadrant plate

what test determines if the isolate requires X factor (hemin)?

porphyrin test

what test is associated with the following information:

• ALA → porphobilinogen → porphyrins → hemin

• porphobilinogen + kovac’s reagent → red color (positive)

• porphyrin + UV light (wood’s light) → red/orange fluorescent (postive)

porphyrin test

the 3 clinically significant species of bordatella include bordatella pertussis, bordatella parapertussis, and bordatella bronchiseptica and are all found in humans, but which of these 3 are often normal flora of a variety of animals (dogs, cats, swine, rabbits,…)?

bordatella bronchiseptica

which bacteria is the causative agent of whooping cough?

bordatella pertussis

what is another term for the condition of whooping cough?

pertussis

what refers to an infection of the tracheobronchial epithelium?

whooping cough

what is the major virulence factor of whooping cough?

pertussis toxin (PT)

what virulence factor causes histamine sensitization, promotion of lymphocytes, insulin secretion, and immune effector cell response?

pertussis toxin (PT)

bordatella pertussis requires special medium for isolation (fastidious) that contain the neutralizing substance _____ because this bacterium is inhibited by many substances.

charcoal

the bacteria ____ will grow on the following media because of the inclusion of charcoal:

• BCYE

• bordet-gengou (BG)

• charcoal horse blood agar

• jones kendrick charcoal agar

bordatella pertussis

bordatella pertussis is very susceptible to environmental changes and survives only briefly outside of the human respiratory tract. true or false?

true

what bacteria is describe below:

• tiny, glistening, compact

  • bisected pearls

  • mercury drops (silver colored)

• may be beta-hemolytic on BG agar

bordatella pertussis

what condition is described below:

• adheres to ciliated bronchial epithelium via filamentous hemagglutinin (Fha) = virulence factor

• bacteria immobilizes the cilia and destroys the ciliated epithelial cells

• bacteria does not directly invade the cells of the respiratory tract

whooping cough

a common complication of whooping cough is _____ (e.g., streptococcus pneumoniae).

superinfection

which stage of whooping cough/pertussis is described below:

• profuse and mucoid rhinorrhea, persisting for 1-2 weeks

• most infectious stage: large # organisms in nasopharynx and mucoid secretions

catarrhal

which stage of whooping cough/pertussis is described below:

• persistent cough (the appearance of this marks the transition away from catarrhal)

• coughing can occur up to 50x a day for 2-4 weeks

  • characteristic inspiratory whoop follows a series of coughs

  • vomiting frequently follows the whoop (when finally breathe air in)

  • exhaustion can occur → barely able to breathe

  • apnea may follow, particularly in infants

paroxysmal

the ____ stage of pertussis/whooping cough depict marked lymphocytosis (even up to 40,000/mm³).

paroxysmal

which stage of whooping cough/pertussis is described below:

• frequency/severity of paroxysmal coughing and other features gradually fade

• 3-4 week stage

convalescent

a partially immune person and those <6 months old may not show all the typical features of the 3 stages of pertussis/whooping cough. true or false?

true

which vaccine is describe below:

• TDaP

  • tetanus, diphtheria, acellular pertussis

• 5 doses: 2 months, 4 months, 6 months, 15-18 months, 4-6 years

childhood

which vaccine is describe below:

• Tdap

  • necessary as vaccinated adolescents and adults can be carriers/spread infection

  • symptoms like common cold

adolescent/adult booster

herd immunity requires ____% of population be vaccinated.

93-95%

those most likely to die due to avoiding vaccinations are _____ (>70% of fatal cases).

infants

which bordatella species is described below:

• causes a less severe pertussis-like illness

• nasopharyngeal swab/aspirate preferred

• fragile bacteria but less fastidious

  • usually isolated on bordatella pertussis media, but can grow on BAP and may grow on CHOC, MAC, and BCYE

bordatella parapertussis

which bordatella species is described below:

• may cause a variety of infections

  • pneumoniae

  • bacteremia

  • wound infections

• not fastidious

  • grows on BAP, CHOC, MAC, SS agars, BCYE, and bordatella media

bordatella bronchiseptica

what identification methods are preferred for bordatella pertussis and parapertussis because the are relatively inactive biochemically?

serologic

direct fluorescent antibody (DFA) can be performed on ____ specimens for the identification of bordatella.

nasopharyngeal

PCR for bordatella pertussis DNA should only test with the S and S of pertussis to avoid the risk of false _____ results.

positive

what bacterial genus is described below:

• faintly staining gram negative coccobacilli

  • to enhance staining: substitute carbol fuchsin for safranin

  • extend counterstain time

• nonmotile, non acid fast, non-spore forming

brucella

brucella is ____ for catalase, oxidase, and urease.

positive

brucella can be zoonotic. which species is associated with the normal flora of the genitourinary tract of cattle?

brucella abortus

brucella can be zoonotic. which species is associated with dogs?

brucella canis

brucella can be zoonotic. which species is associated with sheep and goat?

brucella melitensis

brucella can be zoonotic. which species is associated with pigs?

brucella suis

what bacteria is associated with being a cause for abortion, sterility, and decreased milk production in cattle, goats, and pigs?

brucella

brucella specimens of choice are blood and bone marrow. true or false?

true

what bacteria blood culture should be held in the system for 21-30 days and subcultured every 4-5 days?

brucella

which brucella species is associated with the following:

• CO2 requirement: negative

• H2S production: negative

• growth in presence of:

  • thionin: positive

  • basic fuschin: positive

brucella melitensis

which brucella species is associated with the following:

• CO2 requirement: positive

• H2S production: positive

• growth in presence of:

  • thionin: negative

  • basic fuschin: positive

brucella abortus

which brucella species is associated with the following:

• CO2 requirement: negative

• H2S production: variable

• growth in presence of:

  • thionin: positive

  • basic fuschin: negative

brucella suis

brucella species demonstrate a ____ colony form associated with the presence of small capsule and virulence

smooth

identifying to the genus level (e.g., brucella species) is not sufficient for patient care. true or false?

false

most brucella are catalase, oxidase, UREASE, and NITRATE _____.

positive

brucellosis can be diagnosed by detecting brucella species ____ in patient serum.

antibodies

a common agglutination test for detecting brucella species antibodies uses which species of brucella cells as an antigen to detect the following:

• brucella abortus

• brucella melitensis

• brucella suis

brucella abortus

agglutination test for detecting brucella species antibodies do not detect antibodies to which species of brucella?

brucella canis

what condition refers to an undulant fever acquired through contact with animals or animal products?

brucellosis

what condition is associated with the following:

• ingestion of raw meat of milk (about 10% of infections)

• can enter the body through tiny cracks in the skin or through mucous membranes (e.g., GI tract)

• inhalation infectious aerosols

brucellosis

cases of brucellosis attributed to brucella abortus cattle vaccine strain RB51 are resistant to ____, first line antibiotic used to treat human brucellosis.

rifampin

which BSL is required for culture brucella bacteria?

BSL3

BSL2 precautions do not suffice when handling patient samples containing brucella. true or false?

false

which condition is described below:

• after penetration of skin/mucous membranes, organisms carried within PMNs through the lymph → systemic circulation via lymph nodes and thoracic duct

  • virulent strians can enter and multiply within macrophages in the liver, spleen, bone marrow

  • if not controlled locally, infection progresses with formation of small granulomas and with release of bacteria back into circulation

brucellosis

what condition is associated with recurrent bacteremic episodes: recurrent chills and fever?

brucellosis