W7- Haemophilus, & the HACEK Group Flashcards
HACEK group
-they all reside in human ORAL CAVITY and Nasopharynx and can cause Endocarditis
- Haemophilus
- Aggregabacterium
- Cardiobacterium
- Eikenella
- Kingella
General characteristic of HAEMOPHILUS
- gram (-)
- PLEOMORPHIC coccobacilli or rods
- facultative anaerobic
- ferment carbohydrates
- obligate parasite
- “blood lover’
- require performed growth factors present in blood
Haemophilus
What is the major pathogenic species in the genus Haemophilus
- H. influenzae
- H. aegyptius
- h. ducreyi
X factor
-hemin or hematin
X for UNKNOWN
V factor
- nicotinamide adenine dinucleotide NAD
- V for VITAMIN
T/F
Haemophilus spp. with the prefix PARA need only V factor for growth
TRUE
T/F
if they are V factor dependent they DO NOT GROW in SBA
TRUE
A phenomenon that helps in the recognition of Haemophilus spp. that need V factor
SATELLITISM
T/F
Satellitism happens when an organism, such as S. aureus, S. pneumoniae, Neisseria spp., produces V factor as a by-product of metabolism -
TRUE
What is the virulence factor of Haemophilus influenzae
- capsule
- IgA protease
- Adherance by fimbriae & other structures
- outer membrane proteins & LPS
What virulence factor plays the most signif8icant role (not a;; strains) of H. influenzae
CAPSULE
What serotype of H. influenzae caused the most invasive infection leading cause of meningitis
SEROTYPE B
T/F
NOT ALL strains of H. influenzae are encapsulated
TRUE
What species of the Genus Haemophilus produces IgA protease
H. influenza
What are the two patterns of the disease attributed to H. influenzae
- INVASIVE
- LOCALIZED
a Pattern, caused by encspsulated strains bacteremia plays a significant role
Invasive
(e.g., SAME PT
septicemia, arthritis, meningitis, epiglottitis, pneumonia & tracheitis )
it is the more common pattern of disease
LOCALIZED
e.g.,COS,,, Conjunctivitis, sinusitis Otitis media with effusion in the middle ear infections
it is occasionally associated with invasive diseases
NTHi (non-typepable H. influenzae) strains (e.g., bronchit8is, pneumonia in older patients )
in localized H. influenzae infections, what organ serves as the reservoir in chronic middle ear infections and that the bacteria develop biofilms
Adenoid
Haemophilus Aegyptius
It is associated with an acute contagious conductivitis: PINK EYE
haemophilus aEgYptius
it can cause conjunctivitis, mainly in PEDIATRIC populations
Haemophilus influenzae biogroup aegyptius
it can cause a severe systemic disease: Brazilian purpuric fever
Haemophilus influenzae biogroup aegyptius
