Quinolones, Folic acid antagonists and Urinary antiseptics

Question 1

Fluoroquinolone targets _________ in Gram negatives and _________ in Gram positive bacteria

Answer 1

DNA gyrase, topoisomerase IV

Question 2

Name 3 fluoroquinolones

Answer 2

ciprofloxacin, levofloxacin, moxifloxacin

Question 3

Fluroquinolones should be administered at least _________ hours before consumption of dairy products or substances that contain divalent cations

Answer 3

2 hours

Best on empty stomach

Question 4

Name the two respiratory quinolones

Answer 4

Levofloxacin and moxifloxacin

Question 5

Name at least 3 adverse effects associated with the use of fluroquinolones.

Answer 5

1. Phototoxicity
2. Tendinitis or tendon rupture
3. Prolong QT interval
4. Peripheral Neuropathy
5. GI distress
6. Arthropathy

Question 6

Which antibiotics are known to cause phototoxicity?

Answer 6

Tetracyclines, fluoroquinolones

Question 7

Fluoroquinolones are contraindicated in _________

Answer 7

1. Children < 18 years old

2. Pregnant women

Question 8

Can fluoroquinolones be used when breastfeeding?

Answer 8

No

Question 9

Name 3 folate synthesis inhibitors

Answer 9

Sulfonamides, trimethoprim, cotrimoxazole

Question 10

Folic acid is vitamin B9 that is needed in humans to produce healthy ___________

Answer 10

red blood cells

Question 11

Which enzyme does sulfonamide inhibit?

Answer 11

Dihydropteroate synthase

Question 12

Sulfonamides are only effective in bacteria that synthesize their own __________?

Answer 12

folic acid

Question 13

Sulfonamides can cause nephrotoxicity as a result of __________?

Answer 13

crystalluria

Question 14

G6PD deficient patients using sulfonamides can suffer from __________

Answer 14

hemolytic anemia

Question 15

Usage of sulfonamides in last trimester can cause __________ in newborns

Answer 15

kernicterus

Question 16

Which enzyme does trimethoprim inhibit?

Answer 16

Dihydrofolate reductase

Question 17

Trimethoprim can cause __________ deficiency in humans

Answer 17

folic acid

Question 18

Folic acid deficiency caused by trimethoprim can be managed by giving the patients _____________ .

Answer 18

Folinic acid

Question 19

Cotrimoxazole is a combination of which 2 antibiotics, and in what ratio?

Answer 19

Trimethoprim and sulfamethoxazole, 1:5 respectively

Question 20

Name an antibiotic which is used as the choice of drug for the management of pneumocystis pneumonia

Answer 20

Cotrimoxazole

Question 21

Cotrimoxazole is contraindicated in which trimester(s) of pregnancy?

Answer 21

First and last trimester

Question 22

Name at LEAST two indications for cotrimoxazole

Answer 22

1. Uncomplicated UTI

2. Pneumocystis pneumonia

Question 23

Name at LEAST 3 adverse effects related to the use of cotrimoxazole

Answer 23

1. GI related adverse effects like nausea, vomitting, CDAD
2. Rash
3. Photosensitivity
4. Blood disorders including megaloblastic anemia, leukopenia, and thrombocytopenia
5. Haemolytic anaemia in G6PD deficient patients

Question 24

What is nitrofurantoin’s mechanism of action?

Answer 24

It is converted by the bacteria to a highly active intermediate, which disrupts the synthesis of DNA, RNA and metabolic processes.

Question 25

Nitrofurantoin is effective in treatment of _________ .

Answer 25

lower UTI

Question 26

Nitrofurantoin can cause urine colour to turn _________ .

Answer 26

brown

Question 27

How is nitrofurantoin cleared?

Answer 27

Renal clearance

Question 28

G6PD deficient patients using nitrofurantoin are susceptible to ___________ .

Answer 28

Hematologic disturbances such as hemolytic anemia, leukopenia

Question 29

What is G6PD, and why is it important in red blood cells?

Answer 29

The glucose-6-phosphate dehydrogenase (G6PD) enzyme is the central factor of the antioxidant defense system in red blood cells, which helps maintain high levels of reduced glutathione (GSH) and nicotine adenine dinucleotide phosphate (NADPH), to protect the RBC from oxidative damage caused by reactive oxygen species.

Question 30

Name 3 groups of patients in whom nitrofurantoin may be contraindicated.

Answer 30

1. Patients with impaired renal function
2. Pregnant women (at term > 37 weeks)
3. Infants <1 mth of age

Question 31

What would be examples of recommended treatment options for simple UTI in healthy women of reproductive age?

Answer 31

1. Cotrimoxazole

2. Nitrofurantoin

Question 32

Name an antibiotic that can be administered orally for the management of Pseudomonas aeruginosa

Answer 32

Ciprofloxacin

Question 33

Can ciprofloxacin be used in the management of MRSA infections?

Answer 33

No, due to high rates of resistance.