Pesudomonas  Characteristics(3)

• Motile, polar flagella, obligate aerobe, can grow in nitrogen
• Grow on simple media, likes water and associated with plant material
• some produce water soluble pigments and mucoid polysaccharide capsule.

Pseudomonas Aeruginosa

Characteristics

• Pyocyanin (blue/green) and Fluorescin  (green/yellow) H2O soluble pigments
• Grape like aroma

Pseudomonas aeruginosa

Pathogenic Characteristics

* Opportunistic (debillitated, immunocompromised patients)

* Resistant to many antibiotics

* Cause septicemia, endocarditis, pulmonary, ear, burn, urinary tract, gastrointestinal, eye, musculoskeletal infections

Pseudomonas aerigonosa Virulence Factors

(non toxin factors)

* pili-attachment

* capsule- antiphagocytic, attachment in CF patients

P. aeruginosa

Exotoxin A

P. aerigonosa

Exoenzymes

P Aerigonosa

Cytotoxin

P. aerigonosa

Other Pathogenic Enzymes

* Variety of proteases: elastase, alkaline protease.

* Elastase causes hemorrhage and necrosis

Alkaline protease causes degradation of complement, IgG and IgM

P. aerigonosa

Phospholipase C

Vibrionaceae Characteristics

* Facultative, motile with polar flagella

* Grow well in alkaline media pH9-9.6

* Simple nutritional requirements

* Cholerae, parahaemolyticus, vulnificus, alginolyticus commone pathogens

Cholera

* Caused by V. cholerae O1 and O139 serotypes

* Spread via conaminated water

* colonizes brush border, remains in intestine lumen

*Cholera toxin

* Watery diarrhea, "rice" mucus spots, no blood

* Severe loss of water, hypovolemic shock, metabolic acidosis

Cholera Toxin

* Enterotoxin inducing secretory diarrhea

* A and 5B units, same function as in diptheria

* ADP ribosylates G proteon, increase cAMP.

* Hypersecretoin of Cl- and HCO3-, water follows osmotically

V. parahaemolyticus Characteristics

* Halophilic, Marine, unlike cholerae--> needs salt to grow

* Free living in coastal water

V. parahaemolyticus Infection

* Gastroenteritis from uncooked, raw seafood

* Explosive water diarrhea

* Self limiting

* Pathogeni strains have kana gawa hemolysin (WTF?)

V. vulnificus Infection

* Causes rapidly progressive wound infections

* From exposure to contaminated seawater

*Septicemia following raw oyster consumption

             50% mortality

             Pre-existing liver disease predisposes to          septicemia

Campylobacter Characteristics

* Curved rod, highly motile, microaerophilic

* Gram stain shows S shape, comma shape, and gull winged shape

C. jejuni Infection

* Main cause of diarrheal disease

* Widely in animals- milk, water, food contamination transmits to humans

* Bloody, mucus diarrhea, fever, abdominal cramps

* Infects sml and lrg intestine

* Self limiting within about 1 week

Heliobacter

Characteristics

* Mainly causes stomach and duodenal diseases

* Strongly curved, hard to culture

* Highly motile, microaerophilic

* Urease: allows it to grow at low pH

* Oxidase Positive

H. pylori Infection

* Gastritis, duodenitis, peptic and duodenal ulcers.

*  Found in mucosa of epithelial but doesn't invade mucosa layer

* Exotoxin called vacuolating cytotoxin

* CagA--> unknown function

* Pathogenicity Island--> type IV secretion. Produces a proinflammatory cytokine IL-8

Treponema Characteristics

Spirochetes

* long, slender, spiral Gram -

* Similar wall and membrane to gram - but more flexible

*All motile with periplasmic flagella

* Hard to stain (use darkfield, silber, or Anitbody)

*Slender tightly coiled, 6-10 axial filaments

T. pertenue and T. carateum

• * T. pertenue Cause Yaws in tropics 
• * T. carateum Cause pinta in S.A.
• * Common characteristics:
  • chronic skin lesions
  • non veneral
  • poor personal hygiene, insect vectors
  • give false positive for syphyllis with serological test
  • penicillin sensitive

T. pallidum infection

• syphyllis
• systemmic onset
• two phases
• Diagnose under microscope, serologically, or with Ag. Cannot grow in lab
• Penicillin treatment over long period of time

Congenital Syphyllis

Borrelia Characteristics

* Causes relapsing fever, Lymes disease

* Transmitted by blood sucking arthropods

*  not common to culture for diagnosis

* long, thick spirochetes loose irregular coils with 15-30 axial filaments

Relapsing Fever:

Louse Borne

* From B. recurrentis

* person to person transmission

* Crowding, cold, poverty

* Same clinical picture as Tick borne (another flash card)

Relapsing Fever:

Tick Born

* Caused by B. hermsil

* Tick to human transmission via an animal reservior

* Vacation, outdoor, warm weather

*Same clinical picture as Louse Borne

Relapsing Fever:

Clinical Picture

Sudden onset, fever, chills, headache, muscle pain, vomit, diarrhea

Recovery-disease-Recovery-disease cycle

Illness=Bacteremia

Recovery= Antibody response

Relapse= New Antigen

*Stain with Wright, Gram, or Gimensa to diagnose, no serological testing

Lyme Disease

Caused by B. burgdorferi

3-30 days after bite, erythema chronicum migrans skin lesion

Flu lke symptoms for one month

If persists: neuro-cardio, arthralgias, arthritis

Serological diagnosis for early stage from CSF and blood

Late Stage: no more spirochetes but cross reactivity to Ig cause symptoms

ANUG  (acute necrotizing ulcerative gingivitis)

* B. vincentii, Vincent's Infection, "Trench Mouth"

* Painful, oral infection, inflammation, gingivae ncrosis

* Mix of Borrelia and fusiform gram (-) bacteria make fusispirochete complex.

* Gram stain useful for diagnosis

* Bad oral hygiene, stress, anxiety contribute to infection

*Treat with antibiotics

Leptospiria Characteristics

* Slender, tightly coiled, hooked end(s), 2 axial filaments

* Obligate anaerobes

* Unlike most spirochetes, can be cultured on normal media

Leptospirosis

*Typically animal disease

* L. interrogans is pathogeni species. Pig, Dog, rat serotype transmit to humans via contaminated water or urine in exposed skin or mucus membranes

* Infects brain, lungs, liver, kidney,

*Fever, chills, headache, phtophobia, GI disturbance, msucle pain

* Signs of jaundice, hemorrhage, azotemia=poor prognosis

Leptospirosis

Diagnosis

* Examine specimen with darkfield microscopy

* Culture on Fletcher's media, aerobic, 25C

* Agglutination with serum

          Week 1 use CSF and Blood

          After 1 week, use urine sample

* Treat with antibiotics

Spirochetes

Treponema

Borrelia

Leptospira