Antibiotics 2021new - Lecture notes 1 PDF

Preview

Summary

Review manual...

Description

Advanced Practice Education Associates

Antibiotics

NOTICE: This material is copyrighted by APEA. Your purchase provides access to the Course Manual content for you alone. In addition, your purchase permits printing of ONE copy of the Course Manual content. Printing of multiple copies is a violation of copyright.

OVERVIEW • • •

Difference between gram-positive, gram-negative organisms Beta lactam ring, allergies Antimicrobial spectra of antibiotic classes

44 Copyright 2021 Advanced Practice Education Associates

GRAM-POSITIVE AND GRAM-NEGATIVE ORGANISMS Gram-Positive Bugs • Staphylococcus • Streptococcus • Enterococcus • C. difficile Gram-Negative Bugs • Just about everything else!  Neisseria gonorrhoeae  Neisseria meningitidis  E. coli, Shigella, Campylobacter, Salmonella  Pasteurella  Rickettsia, Borrelia  Proteus, Pseudomonas, Legionella, others Gram-Positive Bugs • Staphylococcus  Staphylococcus aureus (skin) ▪ MSSA (Staphylococcus aureus) (skin) ▪ MRSA (Staphylococcus aureus) (skin)  Staph saprophyticus (UTI, vagina)  Staph epidermis (skin) • Streptococcus  Strep pyogenes (throat)  Strep pneumoniae (lungs)  Strep viridans (dental abscess, endocarditis)  Strep agalactiae (Group B Strep) • Enterococcus  Enterococcus faecalis (urinary tract)  Enterococcus faecium (urinary tract) • Other Gram-Positive Bugs  Clostridium difficile  Listeria monocytogenes (listeriosis): outbreaks in food or ice cream!  Propionibacterium acne (acne)  Corynebacterium diphtheriae (diphtheria)  Clostridium botulinum (botulism)  Clostridium tetani (tetanus)  Bacillus anthracis (anthrax) Gram-Negative Bugs — Just about everything else! • Neisseria gonorrhoeae, meningitidis • Atypical pathogens (Mycoplasma pneumoniae, Chlamydophila pneumoniae, Legionella pneumophila) • E. coli, Shigella, Campylobacter, Salmonella • Pasteurella • Rickettsia, Borrelia • Proteus, Pseudomonas, Legionella, others Empiric Treatment - 2 Concepts • Difference between gram-positive and gram-negative bugs • Beta-lactam ring Additional Notes:

Copyright 2021 Advanced Practice Education Associates

45

BETA-LACTAM RING, ALLERGIES What’s a Beta-Lactam? • It’s an antibiotic with a beta-lactam ring • Any PCN or cephalosporin Beta-Lactam Ring - 2 Points • Allergic reactions • Beta lactamase Question: So, if a patient says, “I’m allergic to penicillin,” Can you safely prescribe a cephalosporin?

Image Copyright StudyBlue Inc. All rights reserved. https://www.studyblue.com/notes/note/n/clinicalpharmacology-of-b-lactam-antibiotics/deck/1059156

__________________________________________________________________________________________ Well … IF you are PCN allergic, you’re either allergic to the pink pentagon OR the blue box

Image Copyright StudyBlue Inc. All rights reserved. https://www.studyblue.com/notes/note/n/clinical-pharmacology-of-b-lactamantibiotics/deck/1059156

Question: If you are allergic to the pink pentagon, can you safely take a cephalosporin? __________________________________________________________________________________________ If you are allergic to the blue box in PCN, can you safely take a cephalosporin? __________________________________________________________________________________________ Allergy to PCN only: How common is it? • Estimated 90-98% of PCN-allergic patients are allergic to the pink pentagon and can safely take cephalosporins! Allergy to PCN and Cephs: How common is it? NOT very! • AT MOST: 2-10% of patients who are allergic to PCN are allergic to the blue box AND will also be allergic to cephalosporins “Amelie's Rules” • Rule 1: Never give a cephalosporin if PCN reaction was anaphylaxis!!! • Rule 2: Don’t give a cephalosporin if PCN reaction was HIVES!!!  Hives = IgE mediated, Type I RXN • Rule 3: Give a cephalosporin if PCN reaction was morbilliform rash!!!

Anaphylaxis Image Copyright © 2017 science4u http://science4u.info/virtuallab/allergy-laboratory/acuteanaphylaxis/

Hives Image Copyright © 2018 DERMBOARD. All Rights Reserved. https://dermboard.org/rashes/hives-urticaria/

46 Copyright 2021 Advanced Practice Education Associates

Morbilliform Rash Image Copyright © 2011 UpToDate Reproduced with permission from: www.visualdx.com. Logical Images, Inc. https://somepomed.org/articulos/contents/mobipreview.ht m?35/30/36329

Morbilliform Rash • Rash is macular or maculopapular, lesions are fixed, area expands over several days • May itch • More prevalent in children • More common with aminopenicillins (amoxicillin and ampicillin) Question: What’s an example of a famous viral infection that occurs with exposure to an antibiotic? __________________________________________________________________________________________ Morbilliform Rash: Usually T cell-mediated • Concurrent viral infections predispose patients to morbilliform rash • Mechanism by which this occurs is unknown Beta-Lactam Ring - Second Point • Allergies • Beta lactamase Image Copyright StudyBlue Inc. All rights reserved. https://www.studyblue.com/notes/note/n/ clinical-pharmacology-of-b-lactamantibiotics/deck/1059156

What is Beta Lactamase? • An enzyme that smart bacteria learn how to produce

What does Beta Lactamase do? • It destroys the beta-lactam ring on PCN and cephalosporins! And if you destroy the blue box … antibiotic won't work!  Some smart chemist … “We will not be outsmarted by the bugs!”

THE ANTIBIOTICS PENICILLINS Ampicillin, Amoxicillin, Penicillin G, Penicillin K Gram-Positive Organisms NOT Staphylococcus Streptococcus Group A, B, C, G Enterococcus, Strep pneumoniae, Drug-resistant Strep pneumoniae (DRSP), C. botulinum (wound, not food) Quiz • Can amoxicillin really kill DRSP? __________________________________________________________________________________________ • What dose for adults? __________________________________________________________________________________________ • What dose for peds? __________________________________________________________________________________________ Pediatric (weight-based dose) can NEVER exceed adult dose! Extended-Spectrum PENICILLINS Amoxicillin/Clavulanic acid (Augmentin) Gram-Positive, Gram-Negative Organisms Beta lactamase, NOT MRSA Streptococcus Group A, B, C, G, Enterococcus, Strep pneumoniae, DRSP, MSSA

H. influenzae, M. catarrhalis, E. coli, Neisseria, C. diphtheria

Quiz • How would you know if a bug produced beta lactamase? __________________________________________________________________________________________ Copyright 2021 Advanced Practice Education Associates

47

Sulfonamides TMP-SMX (Bactrim, Septra) Gram-Negative Organisms MRSA, E. coli ???? Staph: MSSA, MRSA, CA-MRSA, Not Strep, Not E. coli (USE IF COST IS AN ISSUE) Tetracyclines Doxycycline, Minocycline, Vibramycin Gram-Negative Organisms Atypicals, MRSA Minocycline is good choice for MSSA and CA-MRSA Doxy/Mino good choices for atypical pathogens and lower resp tract pathogens

H. flu, E. coli, Legionella, Mycoplasma, Chlamydophila, Rickettsia (tick- and tickborne infections)

Cephalosporins Cephs First Generation Second Generation Third Generation

Coverage Gram + Gram + Gram Gram + Gram - Beta lactamase

Cephalosporins 1st Generation Cephalexin (Keflex), Cefadroxil (Duricef) Gram-Positive Organisms Staph: MSSA, Strep Cephalosporins 2nd Generation Cefuroxime (Ceftin), Cefaclor (Ceclor), Cefprozil (Cefzil) Gram-Positive, Gram-Negative Organisms Staph: MSSA, Streptococcus

H. flu, E. coli, Proteus mirabilis

Cephalosporins 3rd Generation Ceftibuten (Cedax), Cefixime (Suprax) Weak Gram-Positive, Gram-Negative Organisms Beta-lactamase Producers Strep Groups NOT Staph

H. flu, M. cat, E. coli, Klebsiella, Salmonella, Shigella

Cephalosporins Extended-Spectrum 3rd Generation Ceftriaxone (Rocephin), Cefdinir (Omnicef), Cefpodoxime (Vantin), Cefditoren (Spectracef) Gram-Positive, Gram-Negative Organisms Beta-lactamase Producers Strep Staph: MSSA

H. flu, M. cat, E. coli, Salmonella, Shigella, Proteus mirabilis Macrolides - Later Generation Azithromycin (Zithromax), Clarithromycin (Biaxin) Atypical pathogens

Staph: MSSA, ??? Strep, NOT Enterococcus, Listeria 48 Copyright 2021 Advanced Practice Education Associates

M. cat, Legionella sp., Chlamydophila, Mycoplasma

Fluroquinolones Quinolones 2nd Generation 3rd Generation

Coverage Gram Gram + Gram Beta lactamase producers, atypical pathogens, DRSP Gram + Gram - (above the belt) Beta lactamase producers, atypical pathogens, DRSP

4th Generation

Fluoroquinolones 2nd Generation Ciprofloxacin (Cipro) Gram-Negative Organisms, Atypical Pathogens M. cat, H. flu, E. coli, Legionella, Chlamydophila, Mycoplasma, Klebsiella, anthrax, other gramnegatives

Staph: MSSA, ??? Strep, NOT Enterococcus NOT MRSA

Respiratory Fluoroquinolones 3rd Generation Levofloxacin (Levaquin) Gram-Positive, Gram-Negative, Atypical Pathogens, DRSP, Aerobes, Anaerobes Strep: all, M. cat, H. flu, E. coli, Legionella, Chlamydophila, Mycoplasma, Klebsiella, ± Pseudomonas

Staph: MSSA, Listeria NOT MRSA

Respiratory Fluoroquinolones 4th Generation Moxifloxacin (Avelox), Gemifloxacin (Factive), *Delafloxacin (Baxdela) Gram-Positive, Gram-Negative (above the belt), Atypical Pathogens, DRSP Strep: all sp., M. cat, H. flu, Legionella, Chlamydophila, Mycoplasma, Klebsiella

Staph: MSSA, Listeria, Not urinary pathogens *Skin/skin structure inf (MRSA)

Miscellaneous Nitrofurantoin (Macrobid) Bladder pathogens only E. coli Miscellaneous (Lincosamide) Clindamycin Gram-Positives, Aerobes, Anaerobes MSSA, CA-MRSA (usually), Streptococcus Glycopeptide Vancomycin Gram-Positives, Anaerobes MSSA, MRSA, CA-MRSA (usually), Streptococcus

C. difficile (oral)

Do you see antibiotics more clearly?

Copyright 2021 Advanced Practice Education Associates

49

Resources for Antibiotics • • • •

Amelie’s Antibiotic Cards; APEA Pharm in a Flash flashcards; APEA CareOnPoint, a mobile clinical reference tool developed by NPs; available by subscription (provides contact hours): https://apea.com/careonpoint Hollier, A. (Ed.).(2021). Clinical Guidelines in Primary Care. (4th ed.). APEA. Additional Notes:

50 Copyright 2021 Advanced Practice Education Associates...