Home » Microbiology » Klebsiella-Entrobacter-Serratia Group

Klebsiella-Entrobacter-Serratia Group

Most of these are opportunistic bacteria, usually present in the large intestine.

Klebsiella pneumoniae
Klebsiella pneumoniae

Pathogenesis

Klebsiella pneumoniae
Infection with K. pneumonia is usually primary, thus it is non opportunistic bacteria. Very large polysaccharide capsule is present, making it antiphagocytic.

Enterobacter and Serratia
Infection occurs in hospitalized patients. Septic shock may occur due to endotoxins secreted.

Predisposing Factors

Klebsiella

  • Elderly
  • Chronic  respiratory  disease
  • Diabetes
  • Alcoholism
  • Immunity
  • Malnutrition
Enterobacter
Enterobacter

Entrobacter and Serratia

  • Invasive procedures
  • Intravenous catheterization
  • Respiratory intubation
  • Urinary tract manipulation
  • Respiratory therapy devices

Clinical Symptoms

  • Pneumonia
  • UTI
  • Bacteremia
  • Secondary spread to meninges and liver

Klebsiella
•    Thick, bloody, sputum ( current- jelly sputum)
•    Necrosis
•    Abscess formation

K. ozaena
Atrophic rhinitis

K. rhinoscleromatis    

Destructive granuloma of nose and pharynx .

Serratia
Serratia

Lab-Diagnosis  

Specimen
•    Urine
•    Pus
•    Sputum
•    Infected tissues

Microscopy

Following features are observed under microscope:

Klebsiella Enterobacter Serratia
Gram- negative rods Gram- negative rods Gram- negative rods
Non- motile Motile Motile
Capsulated Non Capsulated Non Capsulated
Facultative anaerobe Facultative anaerobe Facultative anaerobe

Culture

Blood agar
On blood agar, Klebsiella give large, grey- white mucoid colonies. Enterobacter form grey white colonies.

MacConkey
On MacConkey agar Klebsiella form mucoid, pink lactose fermenting colonies, while Serratia form non lactose fermenting colonies.

CLED
Klebsiella form yellow, mucoid colonies

Biochemical Tests

  Klebsiella Enterobactor Serratia

 

Urease Slow Strain dependent
Voges proskauer + + +
B-galactosidase + + +
Lactase + + Strain dependent
Mannitol + + +
Glucose + + +
Sucrose + Strain dependent +
Oxidase
Citrate + + +
Motility + +
Indole
Lysine decarboxylase + Strain dependent +

TSI Agar

  Klebsiella Enterobactor Serratia

 

Slant Acidic Acidic Both
Butt Acidic Acidic Acidic
Gas + + Strain dependent
H2S

Check Also

Macroconidia of Epidermophyton floccosum and filamentous hyphae

Cutaneous Mycoses

Cutaneous mycoses are the diseases caused by fungi and involving the skin, hair and nails. …

Leave a Reply

Your email address will not be published. Required fields are marked *