Skip to main content

Pseudomonas aeruginosa /pathogen/laboratory diagnosis/ trentment / AST/

By

www.time2026end.com
Pseudomonas aeruginosa

Scientific classification
Domain:Bacteria
Phylum:Proteobacteria
Class:Gammaproteobacteria
Order:Pseudomonadales
Family:Pseudomonadaceae
Genus:Pseudomonas
Species:
P. aeruginosa
Binomial name
Pseudomonas aeruginosa
  • Gram-negative, rod-shaped bacterium 
  • P. aeruginosa is a Obligate aerobe
  • that can cause disease in plants and animals, including humans.
Image result for pseudomonas aeruginosa

Pathogen


  •  It is found in soil, water, skin flora, and most man-made environments throughout the world.
  • An opportunistic, nosocomial pathogen of immunocompromised individuals, P. aeruginosa typically infects the airway, urinary tract, burns, and wounds, and also causes other blood infections.[25]
  • which can cause infections in the blood, lungs (pneumonia), or other parts of the body after surgery
  • The organism is considered opportunistic insofar as serious infection often occurs during existing diseases or conditions 
Image result for pseudomonas aeruginosa

Laboratory diagnosis

Identification

TestResults
Gram Stain-
Oxidase+
Indole Production-
Methyl Red-
Voges-Proskaeur-
Citrate+
Hydrogen Sulfide Production-
Urea Hydrolysis-
Phenylalanine Deaminase-
Lysine Decarboxylase-
Motility+
Gelatin Hydrolysis+
Acid from lactose-
acid from glucose-

acid from maltose-
acid from mannitol+
acid from sucrose-
nitrate reduction+
DNAse-
Lipase+
Pigment+ (bluish green pigmentation)
Catalase+
HemolysisBeta/variable
Image result for pseudomonas aeruginosa

Treatment

Many P. aeruginosa isolates are resistant to a large range of antibiotics and may demonstrate additional resistance after unsuccessful treatment. It should usually be possible to guide treatment according to laboratory sensitivities, rather than choosing an antibiotic empirically. If antibiotics are started empirically, then every effort should be made to obtain cultures (before administering first dose of antibiotic), and the choice of antibiotic used should be reviewed when the culture results are available.
 Antibiotics that may have activity against P. aeruginosa include:
Image result for pseudomonas aeruginosa disease
  • aminoglycosides (gentamicin, amikacin, tobramycin, but not kanamycin)
  • quinolones (ciprofloxacin, levofloxacin, but not moxifloxacin)
  • cephalosporins (ceftazidime, cefepime, cefoperazone, cefpirome, ceftobiprole, but not cefuroxime, cefotaxime, or ceftriaxone)
  • antipseudomonal penicillins: carboxypenicillins (carbenicillin and ticarcillin), and ureidopenicillins (mezlocillin, azlocillin, and piperacillin). P. aeruginosa is intrinsically resistant to all other penicillins.
  • carbapenems (meropenem, imipenem, doripenem, but not ertapenem)
  • polymyxins (polymyxin B and colistin)[60]
  • monobactams (aztreonam)
Antimicrobial Susceptibility Testing (AST)

Testing Conditions

Medium: Disk diffusion: MHA

Broth dilution: CAMHB
Agar dilution: MHA
Inoculum: Broth culture method or colony suspension, equivalent to a
0.5 McFarland standard
Incubation: 35°C±  2°C; ambient air
Disk diffusion: 16–18 hours
Dilution methods: 16–20 hours

Antimicrobial agent
Disk content
Susceptible
Resistant
piperacillin
100ug
   ³21
£14
ceftazidime
30ug
³18
£14
piperacillin-tazobactam
100ug
³21
£16
amikacin
30ug
³17
£14
aztreonam
30ug
³22
£15
cefepime
30ug
³18
£14
ceftazidime-avibactam
30ug
³21
£20
ciprofloxacin
15ug
³21
£15
doripenem
10ug
³19
£15

Thoroughly washing hands and cleaning equipment in hospitals can help prevent infection. Outside a hospital, avoiding hot tubs and swimming pools that are poorly cared for can help prevent infections. You should remove swimming garments and shower with soap after getting out of the water. Drying your ears after swimming can also help prevent swimmer’s ear.
There are several things you can do to prevent infection if you are recovering from a procedure or receiving a treatment in a hospital:
  • Tell your nurse if any of your dressings become loose or look wet.
  • Tell your nurse if you think any tubes of IV lines have come loose.
  • Make sure you fully understand the treatment or procedure your doctor has requested for you.
References:
M100  Performance Standards for Antimicrobial
Susceptibility Testing-CLSI-2018
Labels:

Comments

Post a Comment

Popular posts from this blog

Simmons Citrate Agar biochemistry test for Enterobacteriaceae

By
Simmons Citrate Agar Simmons Citrate Agar  is an agar medium used for the differentiation of Enterobacteriaceae based on the utilization of citrate as the sole source of carbon.  Ingredients per liter of deionized water: Principle of Simmons Citrate Agar Uses of Simmons Citrate Agar 1.     It is used for the differentiation of Gram-negative bacteria on the basis of citrate utilization. 2.     Simmons Citrate Agar may be used to differentiate citrate-positive  Salmonella enteritidis  and members of  Salmonella  subgenus II, III and IV from the citrate-negative  Salmonella typhi, Salmonella paratyphi  A,  Salmonella pullorum  and  Salmonella gallinarum . 3.     Simmons Citrate Agar is primarily used to aid in the identification of Enterobacteriaceae. Uses include: Escherichia coli ...
Post a Comment
Read more

Triple Sugar Iron Test

By
The Triple Sugar Iron (TSI) Test  To determine the ability of an organism to ferment glucose, lactose, and sucrose, and their ability to produce hydrogen sulfide. Principle The Triple Sugar Iron (TSI) test is a microbiological test named for its ability to test a microorganism’s ability to ferment sugars and to produce hydrogen sulfide. An agar slant of a special medium with multiple sugars constituting a pH-sensitive dye (phenol red), 1% lactose, 1% sucrose, 0.1% glucose, as well as sodium thiosulfate and ferrous sulfate or ferrous ammonium sulfate is used for carrying out the test.  . Due to the building of acid during fermentation, the pH falls. The acid base indicator Phenol red. is incorporated for detecting carbohydrate fermentation that is indicated by the change in color of the carbohydrate medium from orange red to yellow in the pres...
Post a Comment
Read more

Simmons Citrate Test

By
Simmons Citrate Reaction It  used to differentiate among the Gram-Negative bacilli in the family Enterobacteriaceae. Principle  Citrate agar is used to test an organism’s ability to utilize citrate as a source of energy. The medium contains  citrate  as the sole  carbon source  and  inorganic ammonium salts (NH4H2PO4)  as the sole source of  nitrogen . Bacteria that can grow on this medium produce an enzyme,  citrate-permease , capable of converting  citrate  to  pyruvate .  Pyruvate  can then enter the organism’s metabolic cycle for the production of  energy . Growth is indicative of utilization of citrate, an intermediate metabolite in the  Krebs cycle . When the bacteria metabolize  citrate , the  ammonium salts  are broken down to  ammonia , which increases  alkalinity . The shift in pH turns the...
Post a Comment
Read more