1b Flashcards
- distinguishes Klebsiella spp., from other members of the family Enterobacteriaceae
Absence of motility
Usually found in the G.I tract; free living in soil, water and plants
All are possess a polysaccharide capsule (encapsulated)
Klebsiella
Kblebsiella
General Characteristics
Capable of utilizing_____ as carbon source and can grow in____
citrate
KCN broth
Klebsiella
Do not produce indole (except_____!)
They possess______ antigens
Urease___ and ornithine decarboxylase___
K. oyxtoca
O and K
(+)
(-)
Klebsiella
Unable to produce H,S
All are lactose fermenter except (2)
Further ferments glucose via the VP pathway
K. ozaenae and K. rhinoscleromatis
Has a polysaccharide capsule - DISTINCT
FEATURE
• Confers phagocytosis protection and against antimicrobial absorption.
• Responsible for the moist, MUCOID, colonies
• Also tests positive for Neufeld Quellung test (capsular swelling)
Kblebsiella pneumoniae
(Friedlander’s bacilli)
Kblebsiella pneumoniae
Disease Association
• Community - Acquired Pneumonia
(CAP), nosocomial
• Opportunistic infections newborns, elderly patients, among and seriously ill patients.
• Wound infections, UTI
and
bacteraemia
Kblebsiella pneumoniae
is an important cause of ventilator-associated pnuemonia.
Carbapenemase - producing K.pneumoniae
Klebsiella
• - these are versatile Beta-lactamases
that can hydrolyze penicillins, cephalosporins, monobactams, and carbapenems
• Renders many beta lactam drugs inactive
Carbapenemase
Laboratory Diagnosis
Gram stain - Gram negative bacilli
Culture - large, moist, mucoid colonies on EMB, MacConkey and XLD
Kblebsiella pneumoniae (Friedlander’s bacilli)
Growth in KCN using Moeller KCN Broth Base
• Supplemented with potassium cyanide, is useful in differentiating organisms based on their ability to grow in the presence of cyanide.
• Used for the differentiation of the members of Enterobacteriacee on the basis of potassium cyanide tolerance.
Test is positive if there is marked turbidity in the tube. In negative tests, there is no growth.
Kblebsiella pneumoniae (Friedlander’s bacilli)
Bacteria that tolerate KCN -
Bacteria that are inhibited by KCN -
Proteus, Klebsiella, Citrobacter
Salmonella, Shigella, Escherichia
Causative agent of antibiotic-associated hemorrhagic colitis (AAHC).
Kblebsiella oxytoca
• Observed.
during
therapy
amoxicillin, penicillins, or ampicillin.
with amoxicillin-clavulanate,
• Sudden onset of bloody diarrhea a after 2 to 7 days of treatment with the oral antibiotics (mentioned in the previous bullet).
Kblebsiella oxytoca
• Antibiotic therapy disrupts the normal gut microbiota and promotes
the overgrowth of Klebsiella oxytoca with subsequent production of cytotoxin
called tilivallin that mitotic arrestotI host cells and induces apoptosis.
• resolves spontaneously within 2-3 days when the offending antibiotics are discontinued.
antibiotic-associated hemorrhagic colitis (AAHC)
Formerly called Donovania granulomatis then Calymmatobacterium granulomatis before being reclassified as
Klebsiella granulomatis
§ Causes granuloma inguinale – a granulomatous
disease affecting the genitalia and inguinal area
Klebsiella granulomatis
Disease is called donovanosis
§ Transmitted through unprotected sexual intercourse
§ After prolonged incubation of weeks to months, subcutaneous nodules appear on the genitalia or in the genital area
K granulomatis
Kblebsiella granulomatis
are rod-shaped, oval organisms that can be seen in the cytoplasm of mononuclear phagocytes or histiocytes in tissue samples from patients with
granuloma inguinale.
They appear deep purple when
stained with Wright’s stain.
Donovan bodies
Causes Rhinoscleroma a chronic
granulomatous disease
Kblebsiella rhinoscleromatis
commonly affects the nasal cavity
and nasopharynx, but it can also
involve the larynx, trachea, bronchi,
middle ear, and orbit.
Acquired via inhalation of
respiratory droplets containing
the causative agents
Kblebsiella rhinoscleromatis
Kblebsiella rhinoscleromatis
Diagnosis of rhinoscleromatis
depends on the identification of the
pathognomonic_______ which is most prominent during granulomatous phase.
Mickulicz cells
(MCs)
foamy macrophages with numerous
cytoplasmic vacuoles containing
viable and nonviable Klebsiella bacilli
Mickulicz cells (MCs)-
Causative agent of chronic atrophic rhinitis called ozena.
Kblebsiella ozanae
is a disease of the nose in which the bony ridges and mucous membranes of the nose waste away
Transmitted via person-to-person contact
Ozena
