Infectious Diseases

What lab test is used to determine between gram positive Staphylococcus vs Streptococcus

Catalase Test

What species is determined if the bacteria is Catalase Positive (breaks down H2O2)

Staphylococcus

What species is determined if the bacteria is Catalase Negative (no H2O2 breakdown)

Streptococcus

What lab test is used to distinguish Catalase Negative species, Streptococcus

Hemolytic test

What species is determined if it was a (catalase neg) Alpha (partial) Hemolytic Streptococci?

Streptococcus pneumoniae

What species is determined if it was a (catalase neg) Beta (complete) Hemolytic Streptococci?

Streptococcus pyogenes (group A)

Streptococcus agalactiae (group B)

What lab test is used to distinguish between Staphylococcus Aureus vs Staphylococcus Epidermis?

Coagulase Test

What species is determined if the bacteria is Coagulase Positive?

Staphylococcus aureus

What species is determined if the bacteria is Coagulase Negative?

Staphylococcus epidermis

What species is Gram +, Anaerobic, Bacilli

C. difficile

How are Gram -, Aerobic, Bacilli distinguished?

Lactose Fermentation presentation

The following Gram -, Bacilli, Aerobic species are identified to have ___

E. coli
Klebsiella pneumoniae
Enterobacter species

Lactose Fermentation

The following Gram -, Bacilli, Aerobic, Oxidase + species are identified to have ___

Pseudomonas aeruginosa

No Lactose Fermentation

Most clinically relevant Gram -, ANAerobic, Bacilli species

B. fragilis

Identify the class of the following agents:

Penicillins
Cephalosporins
Carbapenems
Monobactams

Beta Lactams

What Beta Lactams do NOT need renal adjustments

Ceftriaxone

Nafcillin

Dicloxacillin

Identify the class of the following agents:

Cipro/Levo/Moxi-floxacin

Fluoroquinolones

Which Fluoroquinolones do NOT need renal adjustments

Moxifloxacin

Identify the class of the following agents:

Azith/Clarith/Eryth-romycin

Macrolides

Which Macrolide DO require renal adjustment

Clarithromycin

T/F: Clindamycin requires renal adjustment

False

T/F: Bactrim requires Renal adjustments

True

T/F: Aminoglycosides require renal adjustments

True, with Therapeutic Drug Monitoring (TDM)

Which specific anti-infection agent DOES require Hepatic adjustments

Metronidazole

T/F: Doxy/Mino-cycline require Renal Adjustments

False

T/F: Vancomycin require renal adjustment

True, with Therapeutic Drug Monitoring (TDM)

T/F: Linezolid requires renal adjustments

False

T/F: Tetracycline require renal adjustments

True

What is Abx allergy Type 1’s mediator with possible signs of Anaphylaxis, Urticaria, Angioedema, Wheezing, Hypotension occurring < 1 hour

IgE

What Abx allergy class has an unknown mediator with possible signs of Maculopapular eruptions or Pruritis occurring >72 hours

Idiopathic

What are the three agents that can be used safely in IgE and non-IgE mediated rxn to PCNs?

Cefazolin

Ceftriaxone

Cefepime

What agents has the biggest cross-reactivity risk PNCs and Cephalosporins

Amoxicillin

Ampicillin

Cephalexin

What classes have low risk for cross-reactivity with all PCNs and Cephalosporins

Carbapenems

Monobactams (Aztreonam)

Patients can outgrow true PCN allergy if they had NO reaction for how long?

5-10 years

T/F: Abx can be used for colonized/contaminated cultures in patients and for viral infections

False

What are the Gram -, multi-drug resistant infections that is considered to be an Urgent threat

Carbapenem-Resistant Enterobacteriaceae (CRE)

What are the Gram -, multi-drug resistant infections that is considered to be a Serious threat

ESBL-producing Enterobacteriaceae

Multidrug-resistant Acinetobacter

Multidrug-resistant Pseudomonas aeruginosa

What is the main antimicrobial resistance mechanism for Gram - infections

Enzymatic modification

If a bacteria has a CTX-M enzyme present, what Abx / Abx structure is it mostly resistant to

Beta-Lactams (except Carbapenems)

What type of bacteria can have CTX-M enzymes present

Extended Spectrum Beta-Lactams (ESBLs)

What is the often the drug class of choice when treating ESBLs

Carbapenems

If a bacteria has a Klebsiella pneumoniae carbapenemases (KPC) enzyme present, what Abx / Abx structure is it mostly resistant to

Beta-Lactams

If a bacteria has a AmpC enzyme present, what Abx / Abx structure is it mostly resistant to

3rd generation Cephalosporins

What antimicrobial resistance mechanism is mainly used in Gram +, S. Aureus

Target site change

What gram +, S. Aureus gene indicates for MRSA, resulting in resistance to all Beta-Lactams

Mec A

What is the main drug to treat MRSA

Vancomycin

What gram +, S. Aureus (and Enterococcus) gene indicates for VRSA, resulting in resistance to all Beta-Lactams and Vancomycin

Van A

What is an indicator that the bacteria is MSSA

Oxacillin and Nafcillin susceptible

What is an indicator that the bacteria is MRSA

Oxacillin, Nafcillin, Beta-Lactam Resistant

S. Aureus MSSA mnemonic

A Cleaning Van Lined with Taro ran over the Back Toe of my Dog and kNOCked him over

S. Aureus MRSA mnemonic

A Cleaning Van Lined with Taro ran over the Back Toe of my Dog

Pseudomonas mnemonic

Even Today, MAFIA Pseudomonas still Challenged 3 out of 4 clinicians

What are the dug of choice for MSSA

Nafcillin

Oxacillin

Cefazolin

what are the drug alternatives for MSSA

Cefazolin (non-IgE)

Vancomycin (true PCN allergy)

What gram status is Aztreonam used for in true PCN allergy patients

Gram Negative

What are the drug of choice for HA-MRSA

Vancomycin

What are the drug alternatives for HA-MRSA

Daptomycin (avoid in pneumonia)

Linezolid (not for bacteremia)

What are the drug of choice for CA-MRSA

Bactrim

What are the drug alternatives for CA-MRSA

Clindamycin

Doxycycline

What are the drug of choice for Pseudomonas

Piperacillin-Tazobactam

Ceftazidime

Cefepime

Carbapenems (except Ertapenem)

Aminoglycosides (no gentamicin; not for monotherapy)

What are the drug alternatives for Pseudomonas

Aztreonam (true PCN allergy)

Cipro/Levo-floxacin

Aminoglycosides (no gentamicin; not for monotherapy)

What is a key consideration when treating Pseudomonas

Utilize 2 agents with different MOA

T/F: when treating Pseudomonas, it is best practice use 2 beta lactams

False; 2 agents of different MOAs