Module #3: Patho/Pharm

Penicillin - bacteriostatic or bactericidal?

• bactericidal

  • kills a wide variety of gram positive and some gram negative bacteria

Penicillin is also know as

beta-lactam antibiotics

• some bacteria produce enzyme (beta-lactamase) capable of of destroying PCN

• to improve effectiveness, typically paired with beta-lactamase inhibitor

penicillin- common formulations

• oral: amoxicillin/clavlanic acid (Augmentin)

• intravenous: ampicillin/sulbactam (Unasyn), piperacillin/tazobactam (Zosyn), Nafcillin

• IM: Procaine, Benzathine

sulfonamides - bacteriostatic or bactericidal?

• bacterostatic

  • effective against some gram-positive and many gram-negative bacteria, but resistance is wide-spread

sulfonamides - common indications?

• UTIs

• treatment or prevention of pneumocystis pneumonia

• ear infections (otitis media)

sulfonamides - formulations

• oral or injectable

  • sulfamethoxazole-trimethoprim (Bactrim, Bactrim DS, Septra)

  • sulfisoxazole (combined with erythomycin)

Cephalosporins - bacteriostatic or bactericidal?

• bactericidal

  • five generations with increasing expanded coverage to include gram positive, gram negative, and/or anaerobic infections

Cephalosporins - common indications?

• strep throat

• ear infections

• UTIs

• skin infections

• meningitis

Cephalosporins - fomulations

• injectable

  • cefazolin (Ancef, Kefzol)

  • ceftriaxone (Rocephin)

  • cefepime (Maxipime)

Carbapenems- bacteriostatic or bactericidal?

• bactericidal

  • broadest antibacterial action of any antibiotics to date (“Big Guns”)

  • risk for seizure activity - may require dose adjustments in renal impairment

Carbapenems - indications

• used for moderate to life-threatening bacterial infections

  • connective tissue

  • complex intrabdominal tissue

  • osteomyelitis

  • meningitis

  • multi-drug resistant hospital-acquired infections

Carbapenems - formulations

• meropenem (Merrem)

• ertapenem (Ivnanz)

• imipenem/cilastatin (Primaxin)

Macrolides - bacteriostatic or bactericidal?

• bacteriostatic - may be contraindicated due to the risk for cardiac dysrhythmia (prolonged QT interval)

Carbapenems - common indications

• community-aquired pneumonia

• Pertussis (whopping cough)

• Uncomplicated skin infections

• Listeria

• Chlamydia

• Legionella

Carbapenems - formulations

• oral

  • clarithromycin (Biaxin)

  • erythromycin

  • azithromycin (Zithromax)→ also available for IV admin

Tetracyclines - bacteriostatic or bactericidal?

• bacteriostatic - broad-spectrum against spirochetes and a variety of gram-negative and gram-positive bacteria

Tetracyclines- used to treat?

• Acne

• Chlamydia

• Syphilis

• RMSF

• Lyme disease

• MRSA

Tetracyclines- formulations

• oral - doxycycline (Vibramycin)

• injection - tigecycline (Glycylcycline)

Aminoglycosides - bacteriostatic or bactericidal?

• bactericidal - highly potent Big Guns for virulent infections

Aminoglycosides - which require monitoring of serum levels for dosing adjustment?

• Nephrotoxic

• Ototoxic

Aminoglycosides - typically used for?

• systemic infection (septicemia)

  • also prophylaxis in high risk GI or GU procedures

Aminoglycosides - formulations

• Intravenous only

  • gentamicin

  • tobramycin

  • streptomycin

what is dosing adjustment based off of?

• based on calculations using lab values

  • Serum Creatinine (renal function)

trough

time of lowest expected drug level

peak

time of highest expected drug level

florquinolones - bacteriostatic or bactericidal?

• bactericidal

  • broad-spectrum of activity

florquinolones - adverse effects

• prolonged QT-interval → lethal cardiac dysrhythmias, hypoglycemia, tendon rupture, Myasthenia gravis

florquinolones - used for

• used for difficult to treat infections

  • UTIs when other options are not effective

  • bacterial prostatitis

  • Anthax

  • Plauge

florquinolones - formulations

• oral or injection

  • ciprofloxacin (Cipro)

  • levofloxacin (Levaquin)

  • moxifloxacin (Avelox)

Glycopeptides -bacteriostatic or bactericidal?

• bactericidal

  • highly potent big guns for virulent infections

glycopeptides - require monitoring of…

• monitoring of serum levels for dosing adjustment

  • Nephrotoxic

  • Ototoxic

  • Monitor for Red Man Syndrome

glycopeptides are commonly used for treating

• MRSA

• complicated skin infections

• C. difficile associated diarrhea

• Endocarditis resistant to beta-lactams and other antibiotics

glycopeptides formulations

• oral or injectable

  • vancomycin (Vancocin)

  • daptomycin

what are common OTC topical antibiotics and some examples

• products that treat or prevent minor cuts, scrapes, or burns on the skin that may get infected with bacteria

• examples available in creams, ointments, and sprays

  • Polysporin (bacitracin/polymyxin)

  • Neosporin (bacitancin/neomycin/polymyxin B)

  • Neosporin Plus (neomycin/polymyxin/pramoxine)

therapeutic response

decrease in specific s/s of infection are noted (fever, elevated WBC count, redness, inflammation, drainage, pain)

sub-therapeutic response

s/s of infection do not improve

superinfection

• pseudomembranous colitis: C. diff

• Secondary infection (thrush, vaginitis)

• resistance

what are common side effects of meds

• nausea

• diarrhea

• fever

• vomiting

• photosensitivity: the sensitivity to light and/or being more prone to sunburn while on tx

• tooth discoloration: most prevalent in children whose teeth are still developing

adverse reactions

allergic reactions or stevens-johnson syndrome

allergic reaction

• hives

• trouble breathing

• swelling of the face or tongue

Stevens-Johnson Syndrome (SJS)

• disorder of the skin and mucous membranes most commonly seen in pt with a weakened immune system or family hx of SJS

  • starts with flu-like symptoms (i.e. sore throat, fever)

  • can be followed by painful rash that spreads like blisters

  • skin pain

  • cough

  • pain in mouth and throat

Rx considerations include

• age

• pregnancy & lactation

• immune system

• renal dysfunction

• hepatic dysfunction

• poor perfusion

• multidrug-resistant organism

MDROs are

• Multidrug-resistant organisms

• need broader coverage

common risk factors of MDROs

• prior antimicrobial therapy in the preceding 3 mos

• hospitalization for greater than 2 days within the preceding 3 mos

• current hospitalization exceeding 5d

• high frequency of resistance in the community or local hospital unit (assessed using hospital antibiograms)

• immunosuppressive diseases and/or therapies

A fungus amoung us

• Candida Auris

• this fungus presents a serious global health threat per CDC for three main reasons:

  • often multidrug-resitant

  • difficult to identify w/ standard lab methods, and can be misidentified in labs w/o specific technology which can lead to inappopriate management

  • has cause outbreaks in healthcare settings

C. Auris risk for infection in healthy people…

• is very low

• in U.S. is spreads mostly in longterm healthcare facilities among patients with severe medical problems

• otherwise healthy people do not seem to be at risk for C. auris infections but can be colonized on the skin

how does antibiotic resistance happen?

1. lots of germs; a few drug resistant

2. antibiotics kill bacteria causing illness, as well as good bacteria protecting the body from infection

3. the drug-resistant bacteria are now allowed to grow and take over

4. some bacteria give their drug-resistance to other bacteria, causing more problems

examples of how antibiotic resistance spreads

• animals get antibiotics and develop resistant bacteria in their guts → drug resistant bacteria can remain on meat from animals when not handled or cooked properly and the bacteria can spread to humans

• fertilized or water containing animal feces and drug-resistant bacteria is used on food crops → drug-resistant bacteria in the animal feces can remain on cops and be eaten and these bacteria can remain in human gut

• can spread in the general community

• person gets care at a hospital or other facility → resistant germs spread direct or indirectly to other pt or on unclean hands of healthcare providers

Large-scale efforts to address AR

• California Antimicrobial Stewardship Program Initiative

• Transatlantic Taskforce on Antimicrobial Resistance (TATFAR)

• U.S. National Action Plan for Combating Antibiotic-Resistant Bacteria

• One Health

Antimicrobial Stewardship for RNs

• vaccinations to prevent infections

• practice and educated others on infection prevention → hand hygiene!!!!

• talk to pt and families about when antibiotics are and are not needed, and discuss possible harms such as allergic reactions, C.diff and antibiotic resistant infections → discourage saving “left-over” antibiotics

• avoid antibiotics for infections of predominantly viral cause

• avoid treating positive cultures in the absence of s/s → treat infection, not contamination/colonization

Nursing Considerations: Infection Control and Tx

1. employ appropriate infection control measures

2. identify infection source and organism

3. advocate for appropriate tx

4. Monitor for S/S side effects and adverse reactions

employ appropriate infection control measures

• prevention via identification removal of unnecessary indwelling devices

• practice proper hand hygiene and environmental disinfection

• utilize PPE correctly and patient isolation when deemed necessary

identify infection source and organism

• ensure cultures are properly collected

• follow-up and communicate culture results

• recognize that antibiotics are not always indicate

advocate for appropriate tx

• limit use of broad spectrum antibiotics

• ensure tx is in line with microbiology results

• engage physicians and pharmacists regarding oral therapy options

Monitor for S/S side effects and adverse reactions

• Educate patient regarding potential side effects & treat PRN

• Recognize s/s of anaphylaxis or other adverse reaction

• Assess for S/S consistent with C. difficile