Microbiology 2% Flashcards
The prevention of sepsis by the exclusion, destruction or inhibition of growth or multiplication of microorganisms from body tissue and fluids.
Antisepsis
Chemical compounds that combat sepsis by inhibiting the growth of microorganisms without necessarily killing them.
Used on skin and tissue, arrest the growth of endogenous microorganisms (resident flora), and must not destroy tissue.
Antiseptics
Free of microorganisms including all spores
Sterile
What is the most difficult bacteria to kill?
Spores
Why are spores difficult to kill?
Because they form a hard, protective coating around themselves(they are encapsulated)
If we kill the spores we know that we….
killed all the microorganisms.
Why do we do spore testing?
To make sure that our method of sterilization is effective.
How is spore testing performed?
With a biological monitoring kit, at set intervals, findings are documented, must recall instruments if bad spore test.
What does the biological monitoring it contain?
An incubator, a box of spore vials, and a log book
How often should you do spore testing?
Depending on how often you run your load…
1x per week, several x per week, or 1 x per mo.
How do you do spore testing?
Take a spore vial, put in pill pack and autoclave it just like you would your instruments. When it comes out take out of pill pack and take that spore vial and put in incubator along with the other spore vial that you didn’t sterilize(this is the control). Incubate both for 48-72 hours or however long kit says to incubate them. When you take them both out they should look different. The one that was sterilized shouldn’t have grown any microorganisms but the one that was not should have. They need to look different if they look the same there is a problem with autoclave. Document findings in the log book.
The absence of microorganisms that cause disease.
Aspesis
A severe, febrile toxic state resulting form infection with microorganisms, with or without septicemia (blood infection)
Sepsis
What does febrile mean?
With a fever
This means that you treat every pt as if they are known to have an infectious disease and take appropriate precautions to prevent the spread of disease.
Universal precautions
How should you disinfect horizontal surfaces?
With and EPA-registered germicide which attacks hepatitis and HIV
What does PPE stand for?
Personal protective equipment
What items are considered PPE?
Masks, gowns, gloves, shoe covers (these 4 are one time use), and goggles(reuseable)
What is the purpose of PPE?
To help protect you from exposure to others’ blood, body fluids, or splash protection or laser light protection.
What is the purpose of PPE?
To help protect you from exposure to others’ blood, body fluids, or splash protection or laser light protection.
Exposure to another’s blood or body fluid either from a needle stick or a splash is know as…
exposure incident
What is your employer required to provide you with if there is an exposure incident?
counseling, testing, and treatment at no charge.
Hepatitis A is transmitted through the ______route
oral, fecal
HIV/AIDS, Hepatitis B, and Hep C are what type of pathogens?
Blood born
Devices that are designed to help prevent needle stick injuries.
Safety syringes
Osha requires the employees be included in the selection of ____
safety devices, including safety needles.
What are the characteristics of a safety syringe?
Barrier between hands and needle
hands to remain behind the needle at all times
An integral part of the device-not an accessory
In effect before disassembly; remains in effect after disposal
As simple as possible; requires little or no training to use effectively
A method of differentiating bacteria based on chemical and physical properties of the cells wall, is almost always the first step in identifying bacteria.
Gram staining
Gram positive microorganisms stain what color?
Blue
Gram negative microorganisms stain….
Pink
Explain how to to gram staining.
1.Obtain a tissue sample
2. Spread tissue evenly and thinly on glass slide
3. Fix smear by quickly passing over flame 2-3x
4. Flood smear with Crystal Violet
5. Gently rinse with tap water
6. Flood with iodine
7. Gently rinse with tap water
8. Decolorize with alcohol or acetone, let excess drain off slide
9. Rinse decolorizer off with tap water
10. Flood slide with counterstain Saffranin
11. Gently rinse slide with tap water
12. Drain slide, allow to air dry
13. Examine slide under microscope
What are the 3 basic types of Bacteria?
Cocci, Bacilli, Sprochetes(spiral)
Which bacteria is round?
Cocci
Which bacteria is a rod shape?
Bacilli
Which bacteria is spiral shaped?
Spirochetes
What type of Bacteria is Staph and Strep?
Cocci
Is Staph and Step gram positive or negative?
Gram positive
What type of bacteria is Gonococcus and Meningococcus?
Cocci
Is Gonococcus and Meningococcus gram positive or negative?
Gram Negative
What type of bacteria is Corneobacterium, Bacillus, and Mycobacterium?
Bacilli
Is Corneobacterium, Bacillus, and Myobacterium gram negative or positive?
Gram positive
What type of bacteria is Pseudomonas, Haemophilus, and Moraxella?
Bacilli
Is Pseudomonas, Haemophilus, and Moraxella gram negative or positive?
Gram negative
What type of bacteria is Syphillis?
Spirochetes
How do microorganisms invade tissue structure?
By some alteration in the tissue structure.
What are some of the things that cause an alteration in the tissue structure of the eye that allows microorganisms to invade?
Trauma, Radiation therapy, ocular sx, inadequate blink, lid abnormalities, tear anomalies, corneal degenerative changes, immuno-compromised (DM, AIDs, oral steroids, alcholism, renal transplant)
Pus producing, appears in skin, boils, and styes (Canada, Northern Us)
Staphylococcus Aureus
The multi-drug resistant form of Staph aureus.
MRSA
What is the most common strep that invades the eye?
Streptococus Pneumoniae
Why doesn’t Strep Pneumoniae stain with gram staining and what is used instead?
Because it is encapsulated
India ink
Streptococcus Pneumoniae cause what eye conditions?
Conjunctivitis, K ulcer, Endophthalmitis
This is the most devastating bacillus to invade the eye, is most common cause of K ulcer in CL wearers, common in Southern US.
Pseudomonas
(CL bacteria)
Spirochete that can’t be seen through routine microscope and must be viewed with Darkfield illumination.
Syphilis
Smallest organisms that are not visible with traditional microscope.
Viruses
Viruses must be viewed with what type of microscopy?
Fluorescence microscopy and Electron microscopy
What are the viruses found in eyes?
Adenovirus, Herpes Zoster Virus Ophthlamicus, and Herpes Simplex Keratitis
Adenovirus causes….
conjunctivitis
What is Darkfield illumination
light is not shined directly on the slide, rarely used since we have blood tests to identify syphilis
Bacteria live ___the cell wall
outside
Viruses live ____the cell.
within
Viruses are much more damaging than bacteria because they….
penetrate the cell wall
________is a common virus we deal with in ophthalmology. It is commonly associated with upper respiratory infection and can cause conjunctivitis.
Adenovirus
What is a positive Hutchinson’s sign?
It means pt with herpes has sores on the tip of her nose, this is a sign that pt is 99% likely to have herpes in the eye. (vice vera if tip of nose clear negative Hutchinson’s sign)
What nerve does the herpes zoster virus reside on?
5th trigeminal Nerve
(sores will follow the midline of face)
Fungi are _____
acellular
How do fungi reproduce?
by using the host metabolism
If pt cornea is scratched by a twig they may develop a what?
Fungi
Chlamydia is _____
intra cellular
Where is Chlamydia common?
The US
A parasite that lives in soil, tap water, spas and some pools that can be devastating to the K
Acanthomeoeba
Candida, Fusarium and Aspergillus are types of what?
Fungi
Chlamydia can cause…
Keratoconjunctivitis, trachoma
Acanthomeoeba is a …..
parasite
How long does it take to get smear results and why?
minutes or hours because we are just staining the and then we look at them under the microscope
How long do culture results take? Why?
Days
Positive as soon as one day
Negative always takes 3 day.
If culture is negative at day 1 or day 2 it doesn’t mean it will be negative at day 3.
What do we use to identify bacteria and fungi
gram stain
What do we use to identify the cell structure and the presence of inclusion bodies(which is evidence of inflammation?
Giemsa and Wright
________contains specific nutrients to allow microorganisms to thrive it can be solid or liquid.
Culture media
By placing an abx soaked disc on a culture plate we can test…….
micro organisms sensitivity to different drugs.
What is the basic medium that we use in ophthalmology?
Blood agar
Petry dishes are incubated ______to lessen the possability of contamination from air born particle and to prevent water condensation from accumulating and disturbing microbs.
upside down
When sending a tissue specimen to the lab send it ______ with formalin if sent to pathology for microscopic exam or send to the lab in sterile jar _____ to bacteriology for culture
fixed
unfixed
