Pseudomonas is a type of bacteria that can cause infections. Pseudomonas is a common genus of bacteria, which can create infections in the body under certain circumstances. There are many different types of Pseudomonas bacteria

1. Pseudomonas
known to cause disease in
humans are associated with
opportunistic infections
Attribution-NonCommercial-ShareAlike
4.0 International (CC BY-NC-SA 4.0)

2. Introduction
• more than 140 species, most of which are saprophytic
• known to cause disease in humans are associated with opportunistic infections,
which are
• Only two species, P mallei and P pseudomallei, produce specific human diseases:
glanders and melioidosis.
• P aeruginosa is a ubiquitous free-living bacterium and is found in most moist
environments, causes disease in hospitalized patients (cancer and burns)
1. P aeruginosa
2. P fluorescens
3. P putida
4. P cepacian
5. P stutzeri
6. P maltophilia
7. P putrefaciens

3. Pseudomonas aeruginosa
• Gram-negative rod, Obligate aerobe, Motile, Oxidase and catalase positive
• 0.5 to 0.8 μm by 1.5 to 3.0 μm, grows well at 25° C to 37° C, can grow even at 42° C
• Almost all strains are motile by means of a single polar flagellum, and some strains
have two or three flagella
• The flagella yield heat-labile antigens (H antigen). Antibodies against this antigen is
used for their serological identification
• PILI: may be antiphagocytic and probably aids in bacterial attachment, thereby
promoting colonization.
• resists high concentrations of salt, dyes, weak antiseptics, and many commonly
used antibiotics.

4. Pseudomonas aeruginosa
Alginate
(cystic fibrosis
isolates,
antiphagocytic)
Pilus
(Attachment)
Flagellum
(motility)
Endotoxin
(shock)
Toxin A
Hemolysin
Pigments
Protease
Exoenzyme S
leukocidin
Structure and pathogenic mechanisms of P aeruginosa.

5. Pathogenesis
• P. aeruginosa can produce a lot of antigens some of them are
• Almost all strains of P aeruginosa are hemolytic on blood agar plates
• Hemolysin produced is toxic to alveolar macrophages and play a role in pulmonary
infections
• This leukocidin (also called cytotoxin) damages lymphocyte
1. Endotoxin
2. Hemolysin
3. Leukocidin
4. Pigments: fluorescein,
pycocyanin
5. Proteases: elastase
6. Toxin A
7. Exoenzyme S
8. Phospholipase c

6. Pathogenesis
• P. aeruginosa can produce a lot of antigens some of them are
• extracellular polysaccharide impede phagocytosis and impair diffusion of
antibiotics.
• Proteases induce formation of hemorrhagic lesions, which become necrotic within
24 hours. It contribute to the tissue destruction that accompanies P aeruginosa eye
or lung infections and may aid bacteria in tissue invasion
1. Endotoxin
2. Hemolysin
3. Leukocidin
4. Pigments: fluorescein,
pycocyanin
5. Proteases: elastase
6. Toxin A
7. Exoenzyme S
8. Phospholipase c

7. Pathogenesis
Toxin A
• most toxic known extracellular protein of P aeruginosa
• Toxicity has been attributed to its ability to inhibit protein synthesis
• by catalyzing the transfer of the ADP-ribosyl moiety of nicotinamide adenine
dinucleotide (NAD) onto elongation factor 2 (EF-2). The resultant ADP-ribosyl-EF-2
complex is inactive in protein synthesis
• most patients surviving P aeruginosa sepsis have elevated levels of antitoxin A
antibody
• toxin A may be a major virulence factor of P aeruginosa
• toxin A-deficient mutants are less virulent

8. Pathogenesis
Exoenzyme S
• A second ADP-ribosyltransferase
• catalyzes the transfer of ADP-ribose onto a number of GTP-binding proteins,
including the product of the proto-oncogene c-H-ras (p2lC-H-ras)
• it does not modify elongation factor 2
• S-deficient mutants are less virulent

9. Clinical Manifestations
• P aeruginosa causes various infections
• most cystic fibrosis patients ultimately die of localized P aeruginosa infections
• Necrotizing P aeruginosa pneumonia may occur in other patients following the use
of contaminated respirators
1. Infections on skin and
skeletal tissues, Burn wounds,
Surgical wounds
2. Respiratory tract: Pneumonia and
chronic infection in cystic fibrosis
patients
3. CNS infections
4. Endocarditis
5. UTI
6. Bacteremia

10. Clinical Manifestations
• Cause severe corneal infections following eye surgery or injury
• It is found in pure culture, especially in children with middle ear infections
• It occasionally causes meningitis following lumbar puncture and endocarditis
following cardiac surgery
• It has been associated with some diarrheal disease episodes

11. Infections of other Pseudomonas
• P maltophilia is found in water and in both raw and pasteurized milk. It has been
associated with pneumonia, endocarditis, urinary tract infections, wound
infections, septicemia, and meningitis
• P cepacian: nosocomial and include endocarditis, necrotizing vasculitis, pneumonia,
wound infections, and urinary tract infections. highly resistant to aminoglycosides
and other antibiotics

12. Symptoms
Blood
A bacterial infection of the blood is called bacteremia. A blood infection is one of
the most severe infections caused by pseudomonas. Symptoms may include:
• fever
• chills
• fatigue
• muscle and joint pain
can also cause very low blood pressure, known as hemodynamic shock, which
can lead to failure of other organs including the heart, kidneys, and liver.

13. Symptoms
Lungs
Infection of the lungs is called pneumonia. Symptoms include:
• chills
• fever
• cough with or without sputum production
• difficulty breathing

14. Symptoms
Skin
When this bacterium infects the skin, it most often affects the hair follicles. This
is called folliculitis. Symptoms may include:
• redness of the skin
• abscess formation in the skin
• draining wounds
• Ecthyma Gangrenosum: Cutaneous infection seen in immunocompromised
and burn patients

15. Symptoms
Ear
An external ear canal infection may sometimes be caused by pseudomonas and
result in “swimmer’s ear.” Symptoms may include:
• swelling
• ear pain
• itching inside the ear
• discharge from the ear
• difficulty hearing

16. Symptoms
Eye
• Acute bacterial conjunctivitis
• Bacterial Keratitis
• Endophthalmitis

17. Symptoms
Eye
Pseudomonas keratitis. There is a large epithelial defect associated with a ring-like stromal
infiltrate, which is “soupy” in appearance owing to stromal necrosis. The noninvolved areas of
the cornea have a characteristic “ground glass” appearance. A small hypopyon is present.

18. Diagnosis
• isolation and laboratory identification
• identified on the basis of its Gram morphology, inability to ferment lactose, a
positive oxidase reaction, its fruity odor, and its ability to grow at 4 2° C
• Fluorescence under ultraviolet radiation helps in early identification of P aeruginosa
colonies and also is useful in suggesting its presence in wounds

19. Diagnosis
Pseudomonas aeruginosa on Pseudomonas cetrimide agar, (a) P.
aeruginosa under light lamp showing green pyocyanin pigment
and (b) P. aeruginosa give fluorescence under UV lamp

20. Control
• by observing proper isolation procedures, aseptic technique, and careful cleaning
and monitoring of respirators, catheters, and other instruments
• Topical therapy of burn wounds with antibacterial agents such as mafenide or silver
sulfadiazine, coupled with surgical debridement
• Pseudomonas aeruginosa is frequently resistant to many commonly used
antibiotics
• many strains are susceptible to gentamicin, tobramycin, colistin, and amikacin
• combination of gentamicin and carbenicillin is frequently used to treat severe
Pseudomonas infections, especially in patients with leukopenia