Klebsiella pneumonia

Babylon Uneversity
College of Medicine
Dept. of Microbiology
Prof.Dr.Ilham AL-Saedi Assist.Prof.Dr.Maysa Salih


Klebsiella pneumonia
? Species of Klebsiella are: Klebsiella aerogenes; K. granulomatis; K. milletis; K. oxytoca; K. cf. planticola B43; K. pneumoniae; K. senegalensis; K. singaporensis; K. variicola
? Gram –negative, baciili
? Have thick capsule
? Member of normal flora of colon
? Free-living in soil and water
? 10% carrier rate in upper respiratory tract
? Have multiple pilli-help in adherence to respiratory and urinary epithelium
• Diseases by Klebsiella pneumonia:
- An opportunistic pathogen
1. Lobar pneumonia: in immunosuppressed host,thick mucoid sputum
2. Urinary tract infections
• Lab identification:
- Culture on MacConkey agar: lactose fermenter and mucouid colonies.
- Citrate+, indole -, non-motile, TSI: butt-acidic, Slant-acidic
• Treatment:
- Among the most resistant of all enterobactericiae to antimicrobials especially for beta-lactam antibiotics.

Enterobacter
• Enterobacter is a genus of common Gram-negative, facultatively anaerobic, rod-shaped bacteria of the family Enterobacteriaceae.
• Several strains of these bacteria are pathogenic and cause opportunistic infections in immunocompromised (usually hospitalized) hosts and in those who are on mechanical ventilation.
• The urinary and respiratory tracts are the most common sites of infection. It is also a fecal coliform, along with Escherichia.
• Two clinically important species from this genus are E. aerogenes and E. cloacae.
• Its laboratory characteristics are lactose positive, indole negative and urease negative and is a non-fecal coliform.
• Enterobacter infections can include bacteremia, lower respiratory tract infections, skin and soft-tissue infections, urinary tract infections (UTIs), endocarditis, intra-abdominal infections, septic arthritis, osteomyelitis, CNS infections, and ophthalmic infections.
• Enterobacter infections can necessitate prolonged hospitalization, multiple and varied imaging studies and laboratory tests, various surgical and nonsurgical procedures, and powerful and expensive antimicrobial agents.
• Enterobacter infections do not have a clinical presentation that is specific enough to differentiate them from other acute bacterial infections.
• Signs of Enterobacter bacteremia include the following:
- Physical examination findings consistent with systemic inflammatory response syndrome (SIRS): Including heart rate that exceeds 90 bpm, a respiratory rate greater than 20, and a temperature above 38°C or below 36°C.
- Fever: Occurring in more than 80% of children and adults with Enterobacter bacteremia.
- Hypotension and shock: Occur in as many as one third of cases.
- Septic shock: Manifested as disseminated intravascular coagulation, jaundice, acute respiratory distress syndrome, and other complications of organ failure.
- Cyanosis and mottling: Frequently reported in children with Enterobacter bacteremia.
- Lower respiratory tract infections.
• Enterobacter lower respiratory tract infections can manifest identically to those caused by Streptococcus pneumoniae or other organisms. The physical examination findings may include the following: High fever or hypothermia, Tachycardia, Hypoxemia, Tachypnea, Cyanosis
• Urine analysis: Always indicated for urinary tract infections (UTIs) Factors in the microbiologic diagnosis and assessment of Enterobacter infection include the following:
• The most important test to document Enterobacter infections is culture; when the patient presents with signs of systemic inflammation (eg, fever, tachycardia, tachypnea) with or without shock (eg, hypotension, decreased urinary output), blood cultures are mandatory Direct Gram staining of the specimen is also useful, because it allows rapid diagnosis of an infection caused by gram-negative bacilli and helps in the selection of antibiotics with known activity against most of these bacteria.
• In the laboratory, growth of Enterobacter isolates is expected to be detectable in 24 hours or less; Enterobacter species grow rapidly on selective (ie, MacConkey) and nonselective (ie, sheep blood) agars.



Proteus
? Gram negative rods
? Activity motile with peritrchous flagella
? Swarming phenomenon on agar media
? Some strains are non-motile (OXK, OX2, OX19).
• Biochemical reactions:
- Non-lactose fermenter
- Urease +ve
- Produce H2S (Black sediment in TSI agar medium
• Important species:
- P. vulgaris
- P. merabilis
• Pathogenicity and diseases
- Normal flora in colon of man and animal
- Free living in water, sewage and decomposing matters
- An opportunistic pathogen
• Causes:
? UTI due to:
1. Active motility- invade urinary tract
2. Urease production- hydrolase urea to ammonia
- Encourage stone formation
- Favor growth of other organisms
? Wound infection
• Lab identification of proteus
- Swarming growth on blood agar
- Non-lactose fermenter on MacConkey agar
- Blackening of TSI due to H2S production
- Urease +, Indole [P. merabilis –ve, p. vulgaris +ve.
• Treatment:
- Usually resistance to penicillin
- Good response to cephalosporin, aminoglycosides and quinolones
• Well-felix reaction
Cell wall O antigen of OX-2, OX-19, OX-K (strains of Proteus) cross-react with antigen of several species of Rickettsia.
These Proteus antigen can be used in laboratory to detect presence of specific antibodies against certain Rickettsia in patients serum.