Control Infection Drugs

(antibacterial)

antimicrobial stewardship

a coordinated program that promotes the appropriate use of antibiotics, which improves patient outcomes and reduces microbial resistance

• sulfonamides

• penicillin

• cephalosporins

• macrolides

• quinolones

• aminoglycosides

• tetracyclines

common categories of antimicrobial

sulfonamides

• were one of the first groups of drugs used as antibiotics

• do not actually destroy bacteria but rather inhibit their growth - considered bacteriostatic antibiotics

• inhibit the growth of susceptible bacteria by preventing bacterial synthesis of folic acid

• for: UTI, Enterobacter species, Escherichia coli, Klebsiella spp., proteus mirabilis, proteus vulgaris, respiratory tract infection, prophylaxis, Stenotrophomonas maltophilia

• contraindicated: pregnant women at term and in infants younger than 2 months of age

beta-lactam antibiotics

• are so named because of the beta-lactam ring that is part of their chemical structure

Penicillins

• are a very large group of chemically related antibiotics that were first derived from a mold (fungus) often seen on bread or fruit

• indication: prevention and treatment of infections caused by gram-positive bacteria, gram-negative and anaerobic coverage, pneumonia, intraabdominal infections, sepsis

• contraindications: drug allergy

• natural penicillins

• penicillinase-resistance penicillins

• aminopenicillins

• extended-spectrum penicillins

4 subgroups of penicillins

lethargy, anxiety, depression, seizures

adverse effects of penicillin (LADS)

cephalosporins

• are semisynthetic antibiotics widely used in clinical practice

• are structurally and pharamacologically related to penicillin which works by interfering bacterial cell wall synthesis

carbapenems

• have the broadest antibacterial action of any antibiotic to date; are bactericidal and inhibit cell wall synthesis

• often reserved for complicated body cavity and connective tissue infections in acutely ill hospitalized patients

• adverse effect: drug-induced seizure activity

• contraindication: anaphylactic-type reactions to penicillin

aztreonam

• is most commonly used when gram-negative coverage is needed in patients with a penicillin allergy

• the only one monobactam in clinical use

macrolides

• are a large group of antibiotics that first became available in the early 1950s with the introduction of erythromycin

• are considered bacteriostatic; however, in high enough concentrations they may be bactericidal to some susceptible bacteria

• MOA: inhibit protein synthesis by binding reversely to the 50S ribosomal subunits of susceptible microorganisms

• indications: streptococcus pyogenes, Haemophilus influenzae, spirochetal infections, gonorrhea and chlamydia and mycoplasma infections

palpitations, chest pain, QT prolongatio

adverse effects of macrolides (PCQ)

tetracyclines

are bacteriostatic drugs that inhibit bacterial protein synthesis by binding to the 30S bacterial ribosome

tigecycline

• is structurally related to minocycline, but is the first in a new class called glycylcyclines

• MOA: inhibiting protein synthesis in susceptible bacteria; inhibit the growth of and kill

• indications: mycoplasma, chlamydia, rickettsia, balantidiasis

• contraindications: drug allergy, avoided in pregnant women and nursing women and in children younger than 8 years of age

• coccus

• bacillus

• coccobacillus

• fusiform bacillus

• vibrio

• spirillum

• spirochete

bacterial morphology shapes (CBCFVSS)

(1) gram-positive organisms

(2) gram-negative organisms

(1) bacteria that stain purple

(2) bacteria that stain red

fevers, chills, sweats, redness, pain and swelling, fatigue, weight loss, increased rbc count, formation of pus

signs and symptoms of infection (FCSRPFWIF)

antibiotics

are most effective when their actions are combined with functioning bodily defense mechanisms

community-associated infection

an infection that is acquired by a person who has not recently (within the past year) been hospitalized or had a medical procedure (e.g., dialysis, surgery, catheterization)

health care-associated infection/ nosocomial infection

• an infection that a patient acquires during the course of receiving the treatment for another condition in a health care institution.

• the infection was not present or incubating at the time of admission but occurs greater than 48 hours after admission

1. methicillin-resistant staphylococcus aureus (MRSA)

2. enterococcus, klebsiella, acinetobacter

1 being one of the most common (MRSA)

2 other serious pathogens (EKA)

handwashing

is the single most important health care professionals can do to not prevent the spread of these potentially deadly infections

empiric therapy

the antibiotic selected is one that can best kill the microorganisms known to be the most common causes of infection

definitive therapy

once the results of culture and sensitivity testing are available (usually in 48-72 hrs), the antibiotic therapy is then tailored to treat the identified organisms by using the most narrow-spectrum, least toxic drug based on sensitivity results

prophylactic antibiotic therapy

this is often the case patients are scheduled to undergo a procedure in which the likelihood of dangerous microbial contamination is high during or after the procedure, that is antibiotics are given for prophylaxis

1. broad-spectrum antibiotics

2. narrow-spectrum antibiotics

1. are those that are active against numerous organisms (gram- postive, negative, anaerobic)

2. are effective against only a few organisms

age, allergy history, kidney or live function, pregnancy status, genetic characteristics, site of infection, host defenses

host factors (AAKPGSH)

teratogens

drugs that cause developmental abnormalities in the fetus

slow acetylation

a common genetic host factor in which the rate of metabolism of certain drugs is reduced

glucose-6-phosphate dehydrogenase deficiency

an inherent disorder in which the RBC are partially or completely deficient of this, a critical enzyme in metabolism of glucose

• penicillin

• cephalosporins

• carbapenems

• monobactams

beta-lactam antibiotics 4 major subclasses

• they share a common structure and mechanism of action; they inhibit the synthesis of the bacterial peptidoglycan cell wall

natural penicillin

1. penicillin G

2. penicillin V

although many modifications of the original natural structure have been made, these are the only 2 in clinical use

1. for IV or IM

2. for PO dosage

penicillinase resistant drugs (cloxacillin, dicloxacillin, nafcillin, oxacillin)

stable against hydrolysis by most staphylococcal penicillinases

aminopenicillins (amoxicillin, ampicillin)

have an amino group attached to the basic penicillin structure that enhances their activity against gram-negative bacteria compared with natural penicillins

extended spectrum drugs (piperacillin, ticarcillin, carbenicillin)

have wider spectra of activity than do all other penicillins