Cultures
match the bug with the drug
Gram Stain
method for IDENTIFYING bacteria.
-If the bacteria are PURPLE, then they are GRAM+ because they have a thick cell wall and retain the purple dye.
-If the bacteria are PINK, they are Gram- because their membranes are thinner.
*Doctors use this method to pre
Sensitivity testing
Test preformed on colonies of bacteria to determine which antibiotic the bacteria is affected by
Bacteriostatic
doesn't kill- inhibits the growth of microorganisms. immune competent system is needed, use to weaken the bacteria, and the persons own immune system takes over
Bacteriocidal
kills-destroys the invading organisms. infection is severe, patient is immune incompetent
Staph aureaus and Staph epidermides
Gram + cocci, like wounds, catheters, surgical sites.
Enterics (e-coli, shigella, salmonella, klebsiella, enterobacter, serratia, proteus
Gram -, like the urinary tract and the lungs
Neisseria
Gram -, likes the genitalia
Haemophilus influenza and Neisseria Meningitides
Gram -, likes the lungs and meninges
Anaerobes
often foul smelling. like the mouth, GI tract, skin, diabetic feet. ex: Bacteriodes Fragilis, Clostridium Difficle (c-diff)
Inhibition of bacterial cell wall synthesis
antibiotic prevents the formation of the cell wall, the acteria becomes osmotically unstable, swells and bursts. Because human cells lack a cell wall, these drugs have "selective toxicity."
EX: penicillins, cephalosporins, carbapenims, monobactims.
Antimetabolites
disrupt critical metabolic reactions inside the bacterial cell therby interfering with bacterial growth. generall considered bacteriostatic.
EX: sulfonamides.
Interference with DNA replication
fluoroquinolones destroy bacteria by interfering with DNA gyrase, an enzyme necessary for synthesis of DNA. The bacteria then die (bacteriocidal).
EX: quinolones, metronidazole.
Interference with protein synthesis (50S Ribosome)
binding to the ribosomal subunit inside of bacterial cells prevents the production of the bacterial protein needed for bacterial growth, causing bacterial death. Can also be damaging to human cells
EX: macrolides
Interference with protein synthesis (30S Ribosome)
prevent protein synthesis by binding to ribosomes. Cause bacteria cell death.
EX: aminoglycosides, tetracyclines.
Type I allergic reactions
hypotension, fever, pruritis, flushing, bronchospasm, wheezing, hives, anaphylaxis , Increased production of IgE antibodies.
Type II reactions
hemolytic anemia, thrombocytopenia, neutropenia, pulmonary, hepatic or renal conditons
Type III reactions
Fever, rash, arthralgias
Type IV reactions
cutaneous reactions, dermatitis, includes contact dermatitis
Pruritis
medical term for itching
Anaphylaxis
life-threatening reaction to a foreign substance; symptoms include blockage of air passages, decreased blood pressure, generalized edema
Hemolytic anemia
Reduction in Red cells due to excessive cell destruction
Thrombocytopenia
an abnormally decreased number of platelets in the blood, impairing the clotting process
neutropenia
The total number of neutrophils are abnormally low putting the patient at increased risk of infection
Arthralgias
muscle pain and aches but with no evidence of arthritis
MRSA
methicillin resistant staphylococcus aureus is not susceptible to extended-penicillin antibiotic forumulas.
EX: methicillin, oxacillin, or nafcillin
VRE
vancomycin resistant enterococcus disrupts mucosal and skin barriers. Considered superinfections and seen in elderly and the debilitated.
Peak Level
the highest blood level achieved
Trough Level
the lowest blood level just before the next dose
Nephrotoxicity
toxicity to the kidneys, manifesting in compromised renal function.most are reversible if identified rapidly and the drug is discontinued.
Hepatotoxicity
a destructive effect on the liver, especially in those who already have liver disease
Ototoxicity
hearing loss, often reversible-- but not always
Superinfection
while already on an antibiotic. caused by an organism different from that which caused the initial infection. The microbe responsible is usually resistant to the treatment given for the initial infection.
prophylaxis
use of a drug to prevent potential for infection of a person at risk
Urticaria
hives; an acute allergic reaction in which round wheals (welts) develop on the skin, usually accompanied by intense itching
Natural Penicillin
penicillin G (Pfizerpen)
cidal
inhibit cell wall synthesis
gram +
give on empty stomach usually combined w/ a salt (K+)
Penicillinase-Resistant Penicillins
nafcillin (Unipen)
Cidal
destroying enzymes & inhibit cell wall synthesis
Staph
give w/ water only (no juices) on empty stomach
Amino-penicillins
ampicillin (Omnipen)
Cidal
inhibit cell wall synthesis through enhanced activity against gram - organisms
Gram + and Gram -
rash is not allergy-OK in pregnancy
Extended-Spectrum Penicillins
ticarcillin (Ticar)
Cidal
inhibit cell wall synthesis & have a greater spectrum of activity
Gram +, More Gram -
Cover pseudomonas. Often used w/ aminoglycosides d/t synergy and ability pseudomonas to develop resistance
Interference with Cell Wall Synthesis
Classifications w/i this category include: penicillins, cephalosporins, carbapenims, monobactims. inhibiting the bacterial enzyme that is necessary for cell division and cellular synthesis.
Cephalosporins
4 generations. derived from synthetically altered fungus. Very similar to penicillins. Newer generations cover more Gram - and less Gram +. Watch for cross sensitivity w/ penicillin
First Generation
cefazolin (Ancef)
Cidal
inhibit cell wall synthesis
Gram +
cheapest
Second Generation
cefoxitin (mefoxin)
Cidal
inhibit cell wall synthesis
Less gram -. More gram +
good for surgical prophylazis and colorectal infections. Not for pseudomonas
Third Generation
cefriazone (Rocephin)
Cidal
inhibit cell wall synthesis
Less gram -. more gram +
crosses blood-brain barrier. Covers pseudomonas
Fourth Generation
cefeprim (Maxipime)
Cidal
inhibit cell wall synthesis
good gram + and - coverage
crosses blood-brain barrier. greater spectrum. Used w/ UTI's and skin infections.
Carbapenems
imipenem-cilastin (primaxin)
Cidal
Binds to penicillin binding proteins and is very resistant to antibiotic-inhibiting actions of some bacteria
VERY broad spectrum VERY potent
primarily for resistant organism. can cause sezures broadest spectra antibiotic
Monobactams
aztreonam (Azactam)
cidal
inhibits cell wall synthesis
gram - narrow spectrum ecoli, klebsiella, pseudomonas
serious systemic inections and UTI's monitor renal function