Question | Answer |
How is gonorrheal conjuctivitis in newborns prevented? | Crede Method- eyes of newborn are rinsed with 1% silver nitrate |
What diseases does the DPT or DTaP immunize against? | A. Dipthera B. Tetnus c.Pertusis |
What is the characteristic lesion of anaerobic infections? | Necrosis- dead tissue |
Which specimens are likely to contain clinically significant anaerobes? | a sample aspirated with needle and syringe or pus from a deep wound with a foul odor. |
Which specimens are unacceptable for anaerobic culture? | A. Swabs from surface wounds B. Coughed up sputum and stomach contents |
What is the Gram stain of Neisseria? | Gram negative diplococci |
Where are Neisseria species normal flora? | Throat, sputum |
What does a direct smear of urethral discharge that is positive for gonorrhea look like? | positive smear- intracellular gram negative diplococci |
What must Neisseria have in the atmosphere to grow? | CO2 |
What is the gram stain of Staphylococcus? | Gram Positive in a cocci cluster |
What is an enterotoxin? | An exotoxin that cause gastrointestinal symptoms like nausea, vomiting, diarrhea. Produced by S. aureus. It is a common cause of food poisoning. |
What are some infections caused by S. aureus? | A. Boils B. Pimples/ Acne C. Wounds/ Post op D.TSS E. HAI- Health care Associated Infection.(nosocomial) |
Where is S. epidermidis normal flora? | Skin, throat and vagina |
What is the gram stain of Streptococcus? | Gram Pos cocci chains |
What does Strep require in the atmosphere to grow? | CO2 |
Define alpha hemolysis | Green halo surrounding colony hemolysis slight or incomplete |
Define beta hemolysis | Clear colorless halo |
Define gamma hemolysis | no change in blood surrounding colony |
Which Lancefield group of the beta Streptococcus is the most pathogenic? | Group A S. pyogenes |
Which Lancefield group causes infection in newborns? | Group B |
What does GBS stand for? | Group B Strep |
What organism is the bacitracin disk test used on? | Beta hemolytic strep |
What are the several infections caused by Group A beta hemolytic Streptococci? | A. Strep throat B. Scarlet fever C. AGN D. Rheumatic Fever (RF) E. Osteomyelitis F. meningitis G. acute endocarditis |
What is an erythrogenic toxin? | An exotoxin that causes a rash. Produced by Group A beta strep |
What is droplet nuclei? | Fine spray given off by nose and mouth |
Where is Enterococcus normal flora and what kind of infection does it frequently cause? | Intestine- Urinary Tract Infection (UTI) |
What is the typical colony appearance of Streptococcus pneumonia? | Gray, mucoid, translucent and alpha hemolytic |
What disease does S. pneumoniae cause? | Lobar pneumonia and otitis media(ear infections) |
What ingredient converts liquid to a solid medium? | Agar |
Describe Selective media | Uses dyes, antibiotics and others. Inhibts growth of certain organisms and permits growth of others. Used for fecal, urine, sputum, bacteria normally present inhibited so pathogens, if present, can be seen. EXAMPLE:strep augar |
Describe differential media | uses dyes, indicators and others Gives colonies of a particular organism a distinct and easily recognizable appearance EXAMPLE: E. Coli |
Describe Enriched media | Contains complex organic materials that certain fastidious organisms require to grow |
What are the four solutions used to do a Gram stains? | A. Crystal violet- primary stain B. Iodine- mordant- sticks in dye C. Acetone/alcohol- decolorizer- strips out dye D. Safranin-counter stain |
What color is Gram positive? | Purple |
What color is Gram negative? | Red |
What shape are cocci? | Round |
What shape are bacilli? | Rod Shape |
What shape are spirilla? | Spiral |
Describe cell wall | Varies in composition, accounts for different stain reactors. Rigid structure, maintains shape, some protection |
Describe plasma membrane | Semi permiable- regulates passage of materials in and out of cell wall |
Describe nucleoid | Area that stores genetic material. DNA and RNA. Not a true nucleus. |
Describe a capsule | A capsule is a sticky or gummy envelope secreted by some bacteria. Protects from phagocytosis associated with virulence mucoid growth on the augar |
Describe flagella | Aids in locomotion, propels cell |
Describe spore/endospore | Thick walled oval body. Resistant to adverse conditions, such as, heat, chemicals, drying, boiling for hours and freezing for 6 months |
Define Aerobe | Will grow in presence of free oxygen |
Describe anaerobe | Can not grow in presence of free oxygen. Obtains oxygen from other oxygen containing molecules |
Describe facultative anaerobe | |
Define obligate anaerobe | Can grow only in complete absence of free oxygen |
What pH is best for bacterial growth? | 7- tolerates narrow range 6-8 |
What is the best time to use bacterial cultures for lab studies? | 18-24 hrs 37 degrees Celsius |
What is sterilization? | Completely destroys all living organisms |
What is pathogen? | Disease causing organism |
What is bactericidal | Causes death of bacteria |
What is bacteriostatic/Bacteriostasis? | Inhibits growth or multiplication of bacteria |
What is Disinfection/ disinfectant? | Eliminates many or all pathogens. Effective against vegetative not spores |
What is Antiseptic? | Prevents or combats infection on the body |
How does incineration sterilize items? | It burns them up and reduces to ashes |
What does the autoclave use to sterilize items? | High heat and moisture/ steam under pressure |
Define normal flora | Present in certain body regions at all times. Do not normally cause diseae |
Define virulence | Ability to cause disease. Can it penetrate, spread, kill RBC's, Kill WBC |
Define opportunist | Can not invade tissue of healthy individual, can become pathogenic if body resistance is lower |
How are specimens labeled? | Patient name, source or site, date, time, physician name |
Which samples would you put in the refrigerator? | Urine in sterile container, sputum and rectal swab |
Which samples would you keep at room temp? | Throat culturette, anaerobic wound, urine preservative |
What samples are put in the incubator? | Any specimen on media |
What are three purposes of transport media? | A. Keeps swab from drying out
B. Maintains favorable pH
C. Prevents active metabolism |
What type of urine sample is used for culture? | Clean catch midstream |
What must be avoided when the patient collects a stool sample? | water from toilet and urine |
How is rickettsiae transmitted? | By insect bites- arthropod vectors |
What does H influenzae cause? | Meningitis in children |
What is the name of the immunization given to prevent infection with H influenzae? | Hib |
What does Bordetella pertussis cause? | Whooping cough |
What does the P in the DPT immunize against? | pertusis |
What are enteric bacilli? | Gram neg causes infection in intestines |
What are the characteristics that all Enterobacteriaceae have? | a. all gram neg bacilli
b.aerobic
c.motile or nomotile
d.all oxidase neg
e. all ferment glucose |
What grows on an EMB plate? | only gram neg |
What is inhibited from growing on EMB? | gram pos |
What can E. Coli cause? | a. UTI
b. pyelonepheitis- infection of kidney
c. infant diarrhea |
How is Shigella transmitted? | Oral Fecal route |
What does Salmonella typhosa cause? | typhoid fever |
How is S. typhosa transmitted? | Oral fecal route |
What is the Gram Stain of Salmonella typhosa? | Gram Neg Bacilli |
Which type of urine sample is required for a urine culture? | clean catch- midstream-sterile container. Refrigerate until plated |
What does each of the following urine culture results mean? a. less than 10,000 CFU/ml b. 10,000-100,000 CFU/mL c.greater than 100,000 CFU/mL d. many species | a. contamination- NF b. possible infection c. infection/ UTI d. appears to be contaminated/ repeat culture if clinically indicated |
What does AFB stand for? | AFB= Acid Fast Bacilli |
What does Mycobacterium tuberculosis cause? | an example of AFB- causes TB |
How is Mycobacterium tuberculosis transmitted? | droplet nuclei |
what are characteristics of spirochetes? | a. spiral b. move by spinning/ turning corkskrew c.stain poorly or not at all with Gram d. does not grow outside the body |
What does Treponema pallidum cause? | Syphilis |
What are two ways to test for syphilis? | a. antibodies against it b. exudate from lesion/ dark field microscopy |
what is the first clinical sigh on syphilis? | chancre- Ulcer |
what does Borreila burgdorferi cause and how is the disease transmitted? | Lyme disease, deer and rodent tick |
What is mycology? | study of fungi |
What is ringworm or tinea? | superficial fungal infection of skin, hair or nails |
How are superficial funfal infections checked for? | KOH potassium hydroxide lactophend blue |
What can Candida albicans cause? | a. Thrush b. vaginitis |
What are parasites? | must live on other living matter. eukaryotic |
What is an O & P test? | Ova and parasite in stool |
How do you perform a cellulose tape collection for Enterobius vermicularis? | causes pinworm - eggs picked up from skin of parianal region with scotch tape |
What size are viruses compared to other living organisms? | They are the smallest living organisms |
Viruses are described as what kind of parasite? And what does that mean? | Obligate intracellular parasite Must reproduce within living cells |
What is the structure of a virus? | DNA or RNA core with a protein coat |
How are viral diseases often diagnosed? | depends on the virus- patient symptoms and direct testing |
Define latency? | State of being inactive can recur |
Define oncogenicity | transform a normal cell into a cancer cell |
Define teratogenicity | Causes physical defects in the embryo fetus |
What is HSV type 1? And symptoms? | Herpes simplex virus Type 1- fever, blisters or cold sores |
What is HSV type 2? and symptoms? | Herpes simplex vrius Type 2- genital herpes- STD |
What is VZV? What does it cause? | Varicella Zoster Virus- Chicken Pox |
What is EBV? What does is cause? | Epstein bar virus- Mononucleosis |
What is HBV? How is it spread? | Hepatitis B virus- Blood and blood products, semen, vaginal secretions and breast milk |
What is HPV? What does it cause? | Human Papilloma Virus- causes warts, genital warts, cervical cancer |
What is Morbillivirus? | causes measles |
What is Rubella? | geman measles |
What is HIV? How is it spread? | Human Immunodeficiency Virus- AIDS- Blood and blood products, semen, vaginal secretions and breast milk |
What is HAV? How is it spread? | Hepatitis A Virus- Oral- Fecal route |
Which viruses are transmitted by the oral-fecal route? | HAV |
Which viruses does the MMR vaccinate against? | Measles, Mumps and Rubella |