Anti-Microbial Therapy

Antibiotic Drug ClassesMajor IndicationsTherapeutic EffectAdverse Reactions

What are Microbes?

Microorganisms (Moos) Bacteria Mycoplasms Spirochetes Fungi Viruses

What are bacteria?

Got Oxygen? Aerobic -need O2 Anaerobic –no O2

Shape Up! Round cocci Rod-like bacilli Spiral spirochetes

Gram’s stain Gram positive Gram negative

A bit o’history

2000BC Here eat this root.

1000AD That root is heathen, say this prayer.

1850AD That prayer is superstition, drink this potion.

1920AD That potion is snake oil, swallow this pill.

1945AD That pill is ineffective, take this penicillin.

1955AD Oops, bugs mutated, take this tetracycline.

1960-1999AD 39 more mutations, take this more powerful antibiotic.

2000AD The bugs have won ! Here eat this root.

Organs of the Immune System

The organs of the immune system are stationed throughout the body. Tonsils & Adenoids Thymus Lymph nodes Spleen Appendix Bone marrow

The Immune Response

Inflammation Protective mechanism of body tissues Histamine, prostaglandins, leukotrienes

Fever Increase thermostat set point

Body vasoconstriction, goose flesh, shiver (heat conservation)

Re-establish normal set point Body increase cutaneous blood flow, sweating

(heat loss)

Moo’s Anatomy

Resistance Gene Exchange

Target Molecule Alter drug receptor

Alter Entry/Removal of drug/pollutant

Inactivate/decompose drug/pollutant Destruction

Sequester/by-pass Develop alternate

pathways to circumvent AB

Mutant Species Development

Spontaneous Mutation DNA change/adapt

Microbial Sex Transduction

To lead across Transformation

Change condition or function

Jumping Genes Conjugation/Acquired

Union, fusion 2 gametes for reproduction

Four Antibiotic RULES

Finish the bottle Don’t be tempted

by leftovers Work with your

health care provider

Don’t skip doses

Antibiotic Action

Inhibit cell wall synthesis Inhibit protein synthesis Prevent folic acid synthesis Interfere with DNA synthesis

Inhibitors of Cell Wall Synthesis

Beta Lactam Compounds Penicillin's MOA & Uses Agents

Penicillin V Dicloxacillin, Methicillin Ampicillin, Amoxicillin-Clavulanate Mezlocillin, Ticarcillin

Cell Wall Inhibitors cont.

Bacteriocidal Allergy/Resistance Pharmacokinetics

Cephalosporins Cephalexin/Cefadroxil Ceftriazone (Rocephin)

Other Inhibitors of Cell Wall Synthesis Vancomycin

Inhibitors of Microbial Protein Synthesis (Bacteriostatic)

Chloramphenicol Tetracycline

Minocycline Macrolides

Azithromycin Clarithromycin Erythromycin

Clindamycin

Amino glycosides Aerobic gram

negative microorganisms Streptomycin Tobramycin Gentamycin

Miscellaneous Metronidazole

Anaerobic bacteria Protozoa

Anti-Folate DNA Gyrase

Sulfonamides “Sulfas”

Sulfasoxazole Single agent

Bacteriostatic Trimethoprim /

Sulfamethoxazole Septra DS Bactrim DS Double agents

Bacteriocidal

Fluoroquinolones “FLOXACINs

Ciprofloxacin Levofloxacin

Clinical Implications

Use Misuse

Patient demand Misdiagnosis Counterfeits Agricultural Use International Travel

Super infection 2% of persons TX w/AB

Serious Drug Interactions

Increase risk of bleed PCN & warfarin PCN & NSAIDs Cephal & warfarin Cephal & NSAIDs

Oto & nephrotox Vancomycin & AG Two or more AG

Antabuse reaction Metronidazole/Etoh Metronid/disulfiram

Summary Slide

Organs of the Immune System The Immune Response Moo’s Anatomy & Resistance Four Antibiotic RULES Inhibitors of Cell Wall Synthesis Inhibitors of Microbial Protein

Synthesis (Bacteriostatic)

Summary Slide (cont.)

Anti-Folate DNA Gyrase Serious Drug Interactions

Case Study Antibiotics

TL is a 29-year-old female, 59 kg, who presents at clinic with a 2-week history of abdominal pain, nocturia and frequency of urination. PE is unremarkable except some lower abdominal tenderness. A clean catch midstream urine sample is collected. The results are 10-25 WBC/HPF with a few gram-positive cocci in clusters and gram negative rods. She is empirically started on Macrobid 100mg bid x 7 days. TL returns to clinic 3 days later with a productive cough, wheezing, and heaviness on her chest and shaking chills. She is severely nauseous. Her breathing is labored with

rales and wheezing. Pregnancy results are positive.

Points to Ponder

Discuss her symptoms and relate them to a possible health problem.

Discuss the antibiotic empiric treatment. Should it be changed?

Consider the relationship between pregnancy and UTI.

What respiratory therapy would you consider?