Term
| Give the distinguishing features of the Pseudomonas genus? What are the important species? |
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Definition
-Gram- rods (like this whole set lol)
-**Oxidase+
-*Strictly aerobic (*don't ferment anything)
-Pseudomonas aeruginosa is the only species of note |
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Term
| What are the distinguishing features of Pseudomonas aeruginosa? |
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Definition
-Has a **blue-green to yellow-green appearance
-**Grape like odor
-Has *oxidase
-Is incapsulated in a slime layer (the "P" in the Some Killers Have Pretty Nice Capsules mnemonic) |
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Term
| Where do we find Pseudomonas aeruginosa and how is it transmitted? |
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Definition
-We find it in **water
-Transmitted on *flowers & raw vegetables; don't allow in burn units anymore |
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Term
| What are the virulence factors for Pseudomonas aeruginosa? |
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Definition
-Endotoxin (as always for gram-)
-**Pseudomonas exotoxin A; ADP ribosylates EF-2 on ribosome inhibiting protein synth
-Capsule/slime layer; antiphagocytic |
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Term
| What are the diseases associated with Pseudomonas aeruginosa? |
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Definition
IN HEALTHY
1. GI colonization; loose stools, transient
2. *Hot tub folliculitis (usually folliculitis is *Staph aureus)
3. Eye ulcers; from trauma
**BURN PATIENTS
4. Cellulitis; with blue green pus -->systemic (sepsis) etc.
NEUTROPENIC PATIENTS & *GGD
5. Pneumonia and sepsis
CATHETERIZED PATIENTS
6. UTIs
*CYSTIC FIBROSIS
7. Pneumonias; hard to get rid of bc of slime layer |
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Term
| How do we diagnose and treat? |
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Definition
-We do a gram stain and culture (it is a distinct color, doesn't ferment, is oxidase positive, and has the odor)
-Easy to culture
-Treat with special antipseudomonal penicillins in combination with other drugs
-Very resistant bc of nosocomial nature
-Because cases are nosocomial, we try to prevent contamination/exposure more than anything |
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Term
| Describe the Francisella genus? What are the members? |
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Definition
-Small gram- rods
-*Facultative intracellular pathogens (in Macs; inhibits phagolysosome formation--> granulomatous response)
-Francisella tularensis is the only member of note
-It is a potential **biowarfare agent via aerosol (Damn that Francis!) |
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Term
| What is the source and transmission? Where is it endemic? |
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Definition
-It is found in wild animals, particularly rabbits and deer (zoonotic)
-Found throughout US, esp. Arkansas and Missouri
-It is transmitted either by **tick bite (dermacentor) or skinning **rabbits (rabbit fever)
-Think of taking grandma Francis hunting haha |
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Term
| What are the diseases? How do we treat? |
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Definition
Tularemia (aka rabbit fever);
1. Ulceroglandular; fever, ulcer at the site of implantation (cut or bite), regional lymph node enlargement
2. Pneumonia; inhaling aerosols (skinning/biowarfare)
3. Typhoidal tularemia; GI from eating undercooked rabbit
-Diagnose mostly by history and then treat with *streptomycin, or prophylax with *live vaccine |
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Term
| What are the members and the identification info for the Bordetella species? |
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Definition
-Bordetella pertussis; gram- small rods, *strict aerobic
-Grows on **Regal-Lowe (newer) or Bordet-Gengou media (types of charcoal blood agar)
-Can also use immunofluorescence etc. |
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Term
| What is the reservoir and the transmission for Bordetella pertussis? |
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Definition
-Vaccinated humans are the reservoir (vaccine protection is gone after about 10 years)
-Transmitted with respiratory droplets |
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Term
| What are the virulence factors for Bordetella pertussis? |
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Definition
1. **Filamentous hemagglutinin; allows attachment to *ciliated epithelial cells (slows the cilia down-->junk)
2. **Pertussis toxin; AB component toxin that causes *ADP ribosylation of Gi (inc. cAMP), effects cell signaling
-Efflux of ions and water
-Activates islet cells-->*hypoglycemia
-Increased histamine sensitivity
3. Adenylate cyclase toxin; inhibits phags and local edema
4. Tracheal cytotoxin; kills cilia |
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Term
| What is the disease and stages for Bordetella pertussis? |
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Definition
Whooping cough;
-Incubation; 7-10
-Catarrhal; 1-2 weeks (cold) [best for diagnosis]
-Paroxysmal; 2-4 weeks (whoops, vomiting)
-Convalescent; 3-4,5, weeks (getting better)
-Can only culture during catarrhal and first half of paroxysmal stage (*Regan-Lowe & Bordet-Gengou*)
-Secondary diseases are often acquired during convalescent stage
-Note, the whoop is to catch your breath after coughing and can get so bad as to produce some cyanosis
-Note that the times are additive (about 2 mo. total) |
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Term
| What is the treatment/prevention for Bordetella pertussis? |
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Definition
-We mainly give supportive care (*erythromycin if <6mo.)
Have two vaccines;
-DTP; old, killed whole bac)
-DTap; newer toxoid and filamentous hemagglutin vaccine |
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Term
| What defines the genus Legionella? Members? |
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Definition
-Pleomorphic rods requiring **cysteine and iron** (buffered charcoal yeast extract, or **BCYE)
-Catalase and oxidase positive
-Stains poorly (usually use florescence instead)
-Live in water
-Legionella pneumophilia (got it's name because of the Legionaries convention were the AC was contaminated) |
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Term
| What do we have to know about Legionella pneumophilia? |
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Definition
-**Facultative intracellular (granulomatous response)
-Associated with contaminated air-conditioning (aerosol)
-**No person to person spread
-Old heavy smokers, alcohol, and IC'd all predispose
1. *Legionnaires disease ("atypical pneumonia")
-Also get diarrhea and mental confusion (not in GI)
2. Pontiac fever; only pneumonitis (not deadly)
-What happens in a younger person (simply milder)
-Treat with erythromycin |
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Term
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Definition
Camplobacter jejuni
ID;
-Curved rods (*gull's wings) with *polar flagella
-*Oxidase positive
-Microaerophilic and grows well at **higher temps (42˚C)
-Grow on Camplobacter or *Skirrow agar
Features;
-***Most common cause of infectious diarrhea worldwide***
-*Low infectious dose and fecal-oral (esp. from **poultry)
-*Invasive-->**blood and pus in stool (rarely septicemia)
-Cross reactivity leads to ***Guillain-Barre syndrome |
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Term
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Definition
-H. pylori is the species
-***Urease positive, *oxidase positive, & *helical with *flagella (motile)
-Microaerophilic
-Urease makes *ammonia to locally neutralize stomach acid
-*Mucinase allows mucous layer penetration
-Leads to **gastric and duodenal ulcers
-Increases risk of **stomach cancers
-Can diagnose with a **breath test for urease after swallowing some 13C-urea-->ammonia + 13C-CO2 |
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Term
| Brucella? Aquired? Disease? |
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Definition
-**Zoonosis; cattle (B. abortus), goats (B. melitensis), pigs (B. suis)-->also unpasteurized milk (esp. travel to Mexico)
-(think vets, ppl in cali and TX, butchers, soldiers, etc.)
-Facultative intracellular-->granulomatous response
BRUCELLOSIS (**undulant fever)
-Goes up and down, often in evening with flu symptoms
-***ProFUUUSE sweating***
-Also a CHRONIC FORM with cyclical bouts of **depression and perfuse sweating**
-Potential in biowarfare |
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