Intro to Microbiology

What pathogens are common for left-sided endocarditis

Strep Viridians

Staph Aureus

What are studies to order for suspected infective endocarditis

TTE

Blood Culture and Stain

What side of the heart is more common to get infective endocarditis

Left

What are risk factors for infective endocarditis

CHD

Degenerative Valvular Disease

Intracardiac Device

IVDA

What are physical signs of infective endocarditis

Petechiae

Splinter Hemorrhage

Janeway Lesions

Osler Nodes

Roth Spots

HACEK pathogens

Organisms that can cause endocarditis

• Haemophilus

• Actinobacillus

• Cardiobacterium hominis

• Eikenella corrodens

• Kingella kingae

What type of bacteria is infective endocarditis is typically

Gram +

What are the steps of gram staining

1. Crystal Violet Dye

2. Gram’s Iodine Solution

3. Decolor (ETOH)

4. Counterstain (Safranin)

What are the results of Gram stain

Purple = +

Red = -

No Stain = Neither

Vancomycin 

An abx that effective at targeting Gram +

What is the MOA of vancomycin

It interferes with the late-stage synthesis of peptidoglycan, an important component of the cell wall of Gram + bacteria

Why does vancomycin not work on Gram - bacteria

They are surrounded by a lipid bilayer

What are indicators of bacteremia

Fever

Malaise

New Murmur

When do we consider sinusitis bacterial

> 1 week of symptoms

What are the most common pathogens for bacterial sinusitis

Strep Pneumonia (+)

H. flu (-)

Moraxella catarrhalis (-)

What is the abx of choice for infective endo

Vancomycin

What is the abx of choice for bacterial sinusitis

Amoxicllin

How does Amoxicillin work

Prevents the synthesis of cell wall

Why does amoxicllin work with some Gram - bacteria

Porin Channels

If someone with sinusitis has had abx within the last 4-6 weeks, what is the drug of choice

Amoxicillin-Clavulanate (Augmentin(

If somone with bacterial sinusitis has a PCN allergy, what is the drug of coice

Macrolides (Azithromycin)

What is the MOA of macrolides

Binds to ribosomes and inhibits protein synthesis in bacteria

What is initial diagnositc test for suspected cholecystitis

RUQ Abd US

What signs indicate a case of acute cholecysitis

RUQ pain

Fever

Leukocytosis

Murphy’s Sign +

If somone has biliary pain but no signs of acute cholecystitis, what should be expected

Biliary Colic

What will labs appear with acute cholecysitis

Leukocytosis

Mild elevate of AST and ALT

Normal Tbili and Alk Phos

What are signs of an US that indicates cholecysitis

Wall thickening

Pericholecystic Fluid

What is the plan of action for acute cholecystitis

Pain Management

NPO with IV Fluids

Consult Surgery

Abx

What types of bacteria are common for acute cholecystitis

Anaerobes

E. coli (-)

Klebsiella (-)

Where are anaerobes most common in the body

Gut 

Mucocutaneous Surfaces

What is the drug of choice for anaerobic infections

Metronidazole

What is the MOA of metronidazole

Inhibits protein synthesis by breaking down DNA

What is the drug of choice for Gram - coverage in acute cholecystisis

Cephalosporins

What is the MOA of cephalosporins

Inhibition of cell wall synthesis 

What is the trend of coverage with cephalosporins

As the generation increases, Gram + coverage gets weaker and Gram - coverage gets stronger

What is the only cephalosporin to work for pseudomonas

Cefazidime

Cephalexin

1st Gen Cephalosporin

Cefazolin

1st Gen cephalosporin

Cefuroxime

2nd Gen Cephalosporin

Ceforxitin

2nd Gen Cephalosporin

Ceftriaxone

3rd Gen Cephalosporin

Cefotazime

3rd Gen Cephalosporin

If cephalosporins cannot be used, what is the drug of choice for Gram - coverrage

Fluoroquinolones

Ciprofloxacin

Fluoroquinolones

Levofloxacin

Fluoroquinolones

What is the drug of choice for acute cholecystitis

Piperacillin-Tazobactam (Zosyn)