Infectious Disease: Other Antibiotics

Question 1

What is the MOA for sulfonamide Abx

Answer 1

inhibit bacterial synthesis of folate

Question 2

What do bacteria require folate for

Answer 2

Thymidine/DNA synthesis

Question 3

What are common Sulfonamide drugs

Answer 3

Sulfamethoxazole (SMX)

Sulfisoxazole

Sulfadiazine

Question 4

How do common Sulfonamide Abx works

Answer 4

Mimic PABA to inhibit Dihydropteroate Synthase

Question 5

What are sulfonamides commonly combined with

Answer 5

Trimethoprim (TMP-SMX)

provides sequential block of THF synthesis

Question 6

What coverage does TMP-SMX provide

Answer 6

Gram (+) including most MRSA

Gram (-) but not Pseudomonas

Question 7

What are 2 major uses for TMP-SMX

Answer 7

Uncomplicated UTI’s

Pneumocystis Pneumonia
-treatment
-prophylaxis

Question 8

What are common adverse effects of Sulfonamides

Answer 8

Hypersensitivity reactions

Nephrotoxicity

Photosensitivity

Hemolysis in G6PD deficient patients

Binds albumin

Question 9

What patient population is associated with Sulfonamide induced Hemolysis

Answer 9

G6PD deficiency

Question 10

What is a consequence of Sulfonamides displacing Albumin

Answer 10

Displaces other substances
-Warfarin: increase INR
-Kernicterus in newborns

Question 11

What is the MOA of Trimethoprim (TMP)

Answer 11

Preferentially inhibits bacterial dihydrofolate reductase to inhibit DNA synthesis of rapidly dividing cells

Question 12

What adverse effect is associated with Trimethoprim

Answer 12

Bone marrow suppression
-Pancytopenia
-megaloblastic anemia
-leukopenia
-thrombocytopenia

Question 13

How can you avoid bone marrow suppression in Trimethoprim use

Answer 13

Folate supplementation

Question 14

What patient population is Trimethoprim (TMP) avoided in

Answer 14

Pregnancy due to increased folate demand

Question 15

What electrolyte abnormality is associated with Trimethoprim (TMP)

Answer 15

Hyperkalemia

Question 16

How does TMP cause Hyperkalemia

Answer 16

blocks ENAC
-blocks K into urine

similar to K sparring diuretics

Question 17

What patients should you be cautious of hyperkalemia in when using TMP

Answer 17

ACE-I

ARBs

Aldosterone Antagonists

Question 18

What is the treatment of choice for Pneumocystis Pneumonia (PCP)

Answer 18

TMP-SMX

Question 19

What are alternative therapies for PCP

Answer 19

Dapsone

Pentamidine

Atovaquone (malaria drug)

Question 20

What is the MOA of Dapsone

Answer 20

Competes with PABA for dihydropteroate Synthase

Question 21

What diseases are Dapsone used in

Answer 21

PCP pneumonia

Mycobacterium Leprae (Leprosy)

Question 22

What is the MOA of Fluoroquinolones

Answer 22

Inhibits Enzymes needed for bacterial DNA synthesis

Question 23

What enzymes are inhibited by Fluoroquinolones

Answer 23

DNA Gyrase

Topoisomerase IV

Question 24

What are common Fluoroquinolone drugs

Answer 24

Ciprofloxacin

Levofloxacin

Moxifloxacin

Question 25

What is the coverage of Fluoroquinolones

Answer 25

Many gram (+) Many Gram (-) Many atypicals

Question 26

What are common uses for Fluoroquinolones

Answer 26

UTI -E. Coli g- Pneumonia -S. Pneumo -H. Flu -Atypicals Abdominal infections -enteric g-

Question 27

What are common used of Ciprofloxacin

Answer 27

Pseudomonas GI infections UTI Otitis Externa (drops)

Question 28

What Fluoroquinolone is most reliable to cover Pseudomonas

Answer 28

Ciprofloxacin

Question 29

What Fluoroquinolones are commonly used in Pneumonia

Answer 29

Levofloxacin Moxifloxacin

Question 30

What Are common adverse effects of Fluoroquinolones

Answer 30

Tendinopathy Neuropathy QT prolongation

Question 31

What patient populations can you not use Fluoroquinolones in

Answer 31

Pregnancy Children

Question 32

What disrupts absorption of Fluoroquinolones

Answer 32

Antacids Sulcralfate

Question 33

What key drugs have absorption disrupted by Antacids (4)

Answer 33

Tetracycline Fluoroquinolones Isoniazid Fe supplements

Question 34

What is the MOA of Vancomycin

Answer 34

Inhibits cell wall synthesis -binds DALA DALA to prevent crosslinking and cause cell death

Question 35

What is Vancomycin effective against

Answer 35

only gram (+) bacteria

Question 36

Why is vancomycin only effective against g (+) bacteria

Answer 36

Too large to pass the outer membrane of g(-) bacteria

Question 37

What are the major uses of Vancomycin (3)

Answer 37

MRSA C. Diff Penicillin-resistant S. Pneumoniae

Question 38

What form is Vancomycin given for MRSA

Answer 38

IV

Question 39

What form of Vancomycin is given for C. Diff

Answer 39

Oral -not absorbed so it only acts in intestines

Question 40

What adverse effects are associated with Vancomycin

Answer 40

Nephrotoxicity Ototoxicity Vancomycin infusion reaction (Red-man syndrome)

Question 41

What Abx class increases the risk of nephrotoxicity with Vancomycin

Answer 41

Aminoglycosides

Question 42

What is the MOA of Metronidazole

Answer 42

Causes DNA breakage/destabilization leading to cell death

Question 43

What is unique about Metronidazole

Answer 43

It is a prodrug that must be reduced to be activated

Question 44

What type of bacteria are capable of reducing Metronidazole to its active form

Answer 44

Only Anaerobic bacteria

Question 45

What are common uses of Metronidazole

Answer 45

H. Pylori Bacterial vaginosis Anaerobic Protozoa "anaerobes below the diaphragm"

Question 46

What is the role of Metronidazole for H. Pylori

Answer 46

Part of triple therapy

Question 47

What is the role of Metronidazole in Bacterial Vaginosis

Answer 47

Treats Gardnerella Vaginalis

Question 48

What anaerobic protozoa does Metronidazole commonly treat

Answer 48

Trichomonas Vaginalis Entamoeba Histolytics Giardia Lamblia

Question 49

What adverse effects are commonly associated with Metronidazole

Answer 49

Unpleasant Metal Taste Abd Discomfort/Nausea Disulfiram-like reaction with alcohol

Question 50

What is the major use of Nitrofurantoin

Answer 50

Uncomplicated UTI

Question 51

What can Nitrofurantoin trigger

Answer 51

Hemolysis in G6PD patients

Question 52

Is Nitrofurantoin safe in pregancy

Answer 52

yes