Fastidious Flashcards
Require growth factors
X and v factor
Non-motile, facultatively anaerobic, oxidase and catalase positive, nitrate reductase positive
Haemophilus
Phenomenon observed in species requiring V factor
Satellitism
Erroneously implicated in the influenza pandemic of 1889-1890
Haemophilus influenzae
What are the virulence factors of Haemophilus influenzae?
- capsule
- IgA protease
- adherence mechanism
- outer membrane proteins
- lipopolysaccharide
Causes osteoarthritis in children
Kingella kingae
Bleach like odor
Haemophilus influenzae
Legionella requires ______ for growth
L-cysteine
Mushroom odor
Haemophilus influenzae
Pinkeye conjunctivitis
Haemophilus aegypticus
Urine specimen for Ag detection
Legionella
What are the two patterns of H. influenzae?
- Encapsulated strains
- unencaosulated strains
Haemophilus influenzae serotype b (HIB) in children
Meningitis
Rapid onset, acute inflammation, intense edema of the epiglottis
Epiglottitis
Life threatening disease in children
Bacterial tracheitis
What is other name of harmophilus aegypticus?
Koch-Weeks bacillus
Observed in conjunctivitis exudates from egyptians by koch in 1883
Haemophilus aegypticus
Associated with pinkeye conjunctivitis
Haemophilus aegypticus
Agent of chancroid, type of genital ulcer disease
Haemophilus ducreyi
Infects mucosal epithelium, genital and nongenital skin, and regional lymph nodes
Haemophilus ducreyi
Endocarditis of insidious onset
Haemophilus parainfluenzae
Pharyngitis
Haemophilus parahaemolyticus
What are the specimen for Haemophilus?
- Blood
- CSF
- middle ear exudate
- joint fluids
What we can use for response specimens
CAP supplemented with bacitracin (300 mg/L)
For H. aegypticus and H. ducreyi what media can we use ?
CAP supplemented with 1% Iso-VitaleX or Vitox
Translucent, tannish, moist, smooth, convex, with distinct odor
Haemophilus influenzae
Small, flat, smooth, nonmucoid, transparent to opaque, tan or yellow
Haemophilus ducreyi
School of fish or railroad tracks appearance
Haemophilus ducreyi
Used to differentiate heme-producing species of Haemophilus
Porphyrin test
Test the ability of the organisms to convert d-aminolevulinic acid (d-ALA) into porphyrins or porphobilinogens
Porphyrin test
Cannot synthesize heme and are not X factor positive (required hemin)
Porphyrin negative
Can synthesize heme and x factor negative
Porphyrin positive
What reagent is addrd to porphobilinogen?
Kovac’s reagent
HACEK
H - Haemophilus
A - aggregatibacter, actinomycetemcomitans, A. aphrophilus
C - cardiobacterium hominis
E - eikenella corrodens
K - kingella spp
Found in dental plaque and gingival scrapings
Colonies are conves, granular, and yellow with an opaque zone near the center of CAP
Aggregatibacter aphrophilus
Isolated from blood, lung tissue, abscessess of the mouth and brain
Isolated grow better in increased carbon dioxide
Aggregatibacter actinomycetemcomitans
Form rosettes, swellings, long filaments or sticklike structures in yeast extract
Cardiobacterium hominis
Agar pitting colonies
Cardiobacterium hominis
Cellulitis in drug addict
Implicated in periodontitis, meningitis, empyema, pneumonia, osteomyelitis, arthritis
Eikenella corrodens
Members are coccobacillary to short bacilli with swuared ends that occur in paird or short chains
Grows on Thayer-Martin agar
Kingella
Has been associated with bacteremia and abscesses
Kingella dinitrificans
Important pathogrn in pediatric population
Kingella kingae
Systemic and pneumonic forms are possible but cutaneous infection resulting from animals bites is common
Pasteurella
What is the most common specie of pasteurella?
Pasteurella multocida
Also known as mediterranean, crimean, malta fevers
Brucella
Nonspecific symptoms occur within 1-4 weeks of exposure
Acute infection
Undulating fevers, arthritis and epididymoorchitis
Subchronic or undulant form
Depression, arthritis, and chronic fatigue syndrome
Chronic form
Four common isolated species of brucella
Brucella melitensis
Brucrlla abortus
Brucella suis
Brucella canis
B. abortus natural host
Cattle
Brucella suis natural host
Swine
B. melitensis natural host
Goat or sheep
B. canis natural host
Dogs
Most common specie of francisella
Francisella tularensis
Zoomotic disease also known as rabbit fever, deerfly fever, lemming fever, water rat trappers’ disease
Tularemia
Associated with nosocomial infection.
Legionella
Most common specie of legionella
Legionella pneumophila
Found in lakes, rivers, hot springs, and mud
Legionella
Media used for isolation of legionella
Buffered charcoal yeast extract agar BCYE with L-cysteine
On BCYE the colonies appear
Grayish white, blue-green, convex, glistening.
Ground glass appearance
Legionella
What are the rapid methods?
- urine antigen test
- direct fluorescent antibody rest
Detection of legionella antigen in urine specimen using radioimmunoassay and enzyme immunoassay
Urine antigen test
Fluorescein isothiocyanate labelled antibodies bind to antigens on the cell surface, and the Ag-Ab complexexls are detected using fluorescent microscope
Direct fluorescent antibody test
Primary human pathogens
Bordetella pertussis and borderella parapertussis
Causes whooping cough or pertussis
Bordetella
Opportunistic pathogen
Bordetella bronchiseptica
What are the virulence factors of bordatella
- filamentous hemagglutinin
- pertactin
- pertussis toxin
- tracheal cytotoxin
Nonspecific signs; infection is highly communicable
Catarrhal phase
Sudden onset of severe, repetitive coughing followed by fever ye characteristics “whoop” at the end of coughing spell
Paroxysmal phase
Decrease in frequency and severity of coughing spells
Convalescent phase
Human disease with no animal reservoir or vector
Acquired through respiratory droplet or direct contact with secretion
Pertussis
One of the most highly communicable diseases of childhood
Pertussis
Respiratory tract pathogen of animals includding dogs, in which it causes kennel cough
Bordetella bronchiseptica
Specimen of choice for brucella
Nasopharyngeal aspirates or swabs
