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Flashcards in ANTIMICROBIALS Deck (230)
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1

The uptake of which type of antibiotics is inhibited by divalent cations?

Tetracyclines

1

What are the AE (6) of sulfonamides?

Hypersensitivity, hemolysis in G6PD, nephrotoxicity (tubulointerstitial nephritis), photosensitivity, KERNICTERUS, and displace drugs from albumin such as warfarin

1

This TB drug blocks the synthesis of mycolic acid

Isoniazid

1

What drug is used to treat Giardia in A) Non pregnant and B) Pregnant

A) metronidazole B) Paramomycin

1

What kind of drugs are nevirapine, delavirdine, and efavirenz?

NNRTI's

2

What are 3 beta-lactamase inhibitors?

Clavulanic acid, sulbactam, and tazobactam

2

What are sulbactam, tazobactam, and clavulanic acid used for?

Beta lactamase inhibitors

2

Which 3rd generation cephalosporin is used against Pseudomonas?

Ceftazidime

2

With which drugs are aminoglycosides synergistic? What problems arise?

Cephalosporins potentiate them but they also increase the risk for nephrotoxicity

2

Which 2 types of antibiotics cannot be taken with antacids?

Tetracyclines and Fluoroquinolones

2

Which 2 antifungals affect cell wall synthesis?

Caspofungin and Anidulfungin

2

In which tissue is griseofulvin most likely to deposit?

Keratin containing tissues

2

What is praziquantel used to Tx?

Flukes such as Schistosoma

2

MOA of zanamavir

neuraminidase inhibitor that decreases release of influenza A and B viral progeny

2

What are the 2 neuraminidase inhibitors?

Zanamavir and Oseltamivir

3

Which bacteria can you NOT use the penicillinase resistant penicillins on?

MRSA

3

What is the MOA of cilastatin, always given with?

Inhibits renal dehydropeptidase I to prevent the breakdown of imipenem

3

Why do you avoid tetracyclines in pregnancy?

Discolored teeth and inhibition of bone growth

3

What is nifurtimox used to Tx?

Trypanosoma cruzi

3

What drug can be used to treat HBV, HCV, and Kaposi's?

IFN alpha

4

What is the mechanism of resistance to the aminopenicillins?

Beta-lactamases (same as regular penicillins)

4

Which monobactam prevents peptidoglycan crosslinking by binding to PBP3

Aztreonam

4

What is the mechanism of resistance to aminoglycosides?

transferase enzymes that inactivate the drug via acetylation, adenylation, or phosphorylation

4

How do you prophylax against recurrent UTI's?

TMP-SMX

4

What is the antiviral that inhibits IMP dehydrogenase indicated for (2)?

This is ribavirin (Chronic Hepatitis C and RSV)

4

What CMV drug must be coadministered with probenecid?

Cidofovir due to nephrotoxicity

5

This drug inhibits renal dehydropeptidase I to prevent breakdown of imipenem

cilastatin

5

What is the AE of zidovudine?

anemia (NRTI)

7

This TB drug blocks arabinosyltransferase and decreases carbohydrate polymerization of the cell wall

Ethambutol

7

How do you prophylax against endocarditis from surgery and dental procedures?

Penicillins

8

Which antibiotic inhibits dihydrofolate reductase? Which drug also does this as an antineoplastic?

Trimethoprim; Methotrexate

9

Which generation of cephalosporins covers gram positive bacteria and Proteus, E. coli, and Klebsiella?

First Generation (PEcK)

9

What is the major AE of chloroquine?

Retinopathy

11

Which type of anemia is formed by trimethoprim? What could you give to rescue?

Megaloblastic anemia (lack of folate); rescue with folinic acid (leucovorin) same as for methotrexate

11

Which enzyme activates isoniazid to the active form?

Mycobacterial Catalase Peroxidase (KatG)

12

How do you prophylax against strep pharyngitis in a kid with Hx of rheumatic fever?

oral penicillin

13

What is the MOA of griseofulvin?

Interferes with fungal microtubules and disrupts mitosis

14

Which drugs block the conversion of lanosterol to ergosterol?

azoles

15

What are the 3 anti-staphylococcal penicillins?

Nafcillin, Oxacillin, and Dicloxacillin

16

MOA of oseltamivir

neuraminidase inhibitor that decreases release of influenza A and B viral progeny

17

What bugs are covered by second generation cephalosporins?

Gram positives, Haemophilus, Enterobacter, Neisseria, Proteus, E. coli, Klebsiella (HEN PEcK)

18

What drug inhibits HIV integrase

Raltegravir

19

What is the advantage of a cephalosporin over a penicillin regarding beta-lactamase?

Cephalosporins are overall less sensitive to beta lactamase

20

Which 2 antifungals affect membrane function?

Amphotericin B, Nystatin

22

Why are tetracyclines so effective against Chlamydia and Rickettsia?

They can accumulate intracellularly

23

In which setting would you choose aztreonam over aminoglycosides? Can you give both?

In renal failure because aminoglycosides are nephrotoxic. However, the two are synergistic so can be given together under other circumstances.

23

Describe the full MOA of acyclovir

Gets into cells and is monophosporylated by viral thymidine kinase to the active form. This then functions as a guanosine analog and causes CHAIN TERMINATION (no 3' OH)

25

What is the MOA of macrolides?

Bind to 23S rRNA at the 50S ribosome and prevent translocation

25

How do you treat tuberculous leprosy?

Dapsone and Rifampin

25

What is famciclovir used for?

VZV; this drug is related to acylclovir

27

MOA of ergosterol

Binds ergosterol to form membrane pores in fungi

28

What is the MOA of flucytosine? Used for?

blocks DNA and RNA synthesis by using cytosine deaminase to convert to 5 FU

28

What other disorders can hydroxychloroquine be used for aside from malaria?

Rheumatologic disorders

29

What highly virulent bug is covered by ceftaroline?

MRSA

30

Which beta-lactams may cause vitamin K deficiency? How would this manifest?

Cephalosporins, bleeding (loss of II, VII, IX, X, and proteins C and S)

31

2 antibiotic classes inhibiting 30 S

Aminoglycosides and tetracyclines

32

What are the 4 AE of vancomycin?

Nephrotoxicity, Ototoxicity, and Thrombophlebitis as well as Red Man Syndrome

32

This antibiotic blocks peptidyltransferase at the 50S subunit

Chloramphenicol

34

What is the mechanism of resistance to tetracyclines?

Decreased uptake by cells or increased efflux by PLASMID ENCODED GENES

35

Which antibiotics function by blocking DNA topoisomerase II and IV?

Fluoroquinolones

36

Which TB drug may cause optic neuropathy?

Ethambutol

37

AE of macrolides (5)

Motility issues, Arrhythmia (QT prolonged), Cholestatic hepatitis, Rash, eOsinophilia (MACRO)

38

What is the MOA of aminoglycosides

Bind 30 S ribosome to inhibit formation of initiation complex

38

What are the 2 most serious side effects of amphotericin

Nephrotoxicity and Arryhthmias (and the arrhythmias are ultimately due to the nephrotoxicity)

40

How do you prophylax against gonococcal and chlamydial conjunctivitis in a newborn?

Erythromycin ointment

41

What determines the half life of isoniazid?

whether the person is a fast or slow acetylator

41

How can you reverse the bone marrow suppression caused by NRTI's?

G-CSF and EPO

42

What do you use to treat onychomycosis?

Terbinafine

44

What is the DOC for Leishmaniasis?

Sodium Stibogluconate

45

How do you prophylax against meningitis?

Ciprofloxacin = adults; Rifampin = kids

46

Why do you avoid chloramphenicol in pregnancy?

Gray Baby syndrome, baby has low levels of UDP glucuronyl transferase

47

What must you co-administer with cidofovir?

It is nephrotoxic so it should be given probenicid and IV saline to decrease toxicity

48

What is the mechanism of resistance to penicillins?

Beta Lactamase

48

Which antibiotic is best for anaerobes below the diaphragm?

Metronidazole

49

Which ribosomal inhibitors can cause QT prolongation?

macrolides

49

Which antiviral inhibits IMP dehydrogenase?

Ribavirin

50

What is used to Tx flukes such as Schistosomes?

Praziquantel

51

What kind of bugs are covered by 3rd generation cephalosporins?

Serious gram negative infections

52

Why do you avoid aminoglycosides in pregnancy?

They are ototoxic

54

What is IFN B used to TX?

Multiple Sclerosis

55

What are the AE of ribavirin (2)?

Hemolytic anemia and SEVERE TERATOGEN

56

Which drugs inhibit squalene epoxidase and therefore prevent formation of lanosterol?

Terbinafine and Naftifine

57

How do you prevent red man syndrome?

Antihistamines and a slow infusion rate of vancomycin

58

Which azole is best for candidal infections of all kinds?

Fluconazole

59

Which tetracycline is best for a renally impaired patient?

Doxycycline because it is fecally excreted

61

This tetracycline is excreted fecally rather than renally

Doxycycline

62

What autoantibodies may be found in the serum of a person on isoniazid?

Antihistone; it causes a lupus like syndrome

63

What is the mechanism of resistance to macrolides

methylation of the 23S rRNA binding site

65

What is the MOA of chloroquine?

Blocks detoxification of heme to HEMOZOIN so heme accumulates and is toxic to plasmodia

66

Which antifungal drug interferes with microtubule function and may be carcinogenic?

Griseofulvin

68

Which cephalosporin covers MRSA?

Ceftaroline

69

Why do infants on chloramphenicol get "Gray baby syndrome"

They lack liver UDP-glucuronyl transferase to glucuronidate it

70

What are the main 3 AE of protease inhibitors?

Hyperglycemia, GI intolerance, and Lipodystrophy

72

Which 2 antifungals inhibit lanosterol synthesis?

Naftifine and Terbinafine

73

Ototoxicity with aminoglycosides is potentiated with __________ while nephrotoxicity is potentiated with ______________

Loop diuretics; Cephalosporins

74

Which drugs are given as prophylaxis for A) Mycobacterium tuberculosis B) MAC and C) M. leprae?

A) Isoniazid B) Azithromycin (when CD4

76

Why is cefazolin used prior to surgery?

To prevent staphylococcal wound infections

78

What do you use to treat NADPH oxidase deficiency?

IFN gamma

79

Major AE of rifampin

orange body fluids and hepatoxicity (induce CYP450)

80

Which protease inhibitor is used to "boost" others by inhibiting cytochrome P450?

Ritonavir

81

Which antiviral should you use against HSV? VZV?

HSV = Acyclovir; VZV = Famciclovir

82

What is the AE of raltegravir?

hypercholesterolemia

83

What are suramin and melarsoprol used to treat?

Trypanosoma brucei

84

Which tetracycline is rarely used as an antibiotic but instead to act as a diuretic in SIADH?

Demeclocycline

85

Why do you avoid clarithromycin in pregnancy?

Embryotoxic

86

What is the utility of ritonavir vs. other protease inhibitors?

Ritonavir is used to boost the concentrations of others by inhibiting cytochrome P450

87

Which medication would increase the likelihood of tendon rupture in a patient taking fluoroquinolones?

Corticosteroids (prednisone)

88

What are the AE of cephalosporins?

Hypersensitivity, Vitamin K deficiency (bleeding), and increased nephrotoxicity of aminoglycosides

89

Aminoglycosides and tetracyclines both act on _____ S

30 S

91

What is valganciclovir?

Prodrug of ganciclovir with better oral bioavailability

92

What are the 4 AE of aminoglycosides?

Nephrotoxicity, Neuromuscular blockade, Ototoxicity, and Teratogenic

93

Which ribosomal inhibitors can cause cholestatic hepatitis?

Macrolides

95

Which azole is best for Blastomyces, Coccidiodes, and Histoplasma?

Itraconazle

97

Name 2 aminopenicillins

Ampicillin and Amoxicillin

98

What are 3 AE of ampicillin?

Hypersensitivity, Ampicillin rash if underlying mono, and pseudomembranous colitis

99

DOC for 1) T. brucei 2) T. cruzi

1) Suramin and Melarsoprol 2) Nifurtimox

101

How do you treat lepromatous leprosy?

Dapson, Rifampin, and Clofazimine

102

DOC for Trypanosoma brucei

Suramin and melarsoprol

104

What can be treated with IFN alpha? (3)

HBV, HCV, and Kaposi

105

What is the general rule for clindamycin and metronidazole?

Clindamycin = anaerobes above the diaphragm; Metronidazole = anaerobes below the diaphragm

106

Name 3 CMV drugs

Ganciclovir, Foscarnet, and Cidofovir

108

Which drugs potentiate the nephrotoxicity of aminoglycosides?

Cephalosporins

109

Which azole is most likely to cause gynecomastia?

Ketoconazole by inhibiting testosterone synthesis

110

MOA of trimethoprim

Inhibits dihydrofolate reductase

111

What cephalosporin is used prior to surgery to prevent S. aureus skin infections?

cefazolin

112

What is the MOA of tetracyclines?

Inhibit 30 S to prevent attachment of aminoacyl tRNA

114

What drug is often co-administered with ticarcillin and piperacillin? Why?

Clavulanic acid, inhibits beta lactamase

115

Which protease inhibitor can cause hematuria?

Indinavir

116

Which ribosomal inhibitor has a dose dependent risk of aplastic anemia?

chloramphenicol

117

Which antifungals inhibit ergosterol SYNTHESIS?

the conazoles

118

Which bacteria is penicillin most effective for?

Gram positives but also some gram negatives and spirochetes (Syphilis)

119

What is triple therapy for H pylori?

Metronidazole, Clarithromycin and PPI's

120

What is the MOA of ethambutol? AE?

Blocks arabinosyltransferase which decreases carbohydrate polymerization of the cell wall; optic neuropathy

121

What is the MOA of caspofungin and micafungin

inhibit cell wall synthesis by inhibiting synthesis of B-glucan

122

MOA of metronidazole?

disulfiram like reaction, headache, and metallic taste

124

How do you prevent postsurgical infection due to S. aureus?

Cefazolin

125

Which antifungals inhibit nucleic acid synthesis?

5-Flucytosine

127

What kind of bugs are covered by 4th generation cephalosporins?

Pseudomonas and gram positives

128

What 2 types of HSV infections can you use acyclovir for? What is the benefit of valacyclovir?

mucocutaneous (i.e. genitals and cold sores) and encephalitis; better oral bioavailability

129

Which types of bugs can carbapenems be used against?

Gram positive, Gram negative, and anaerobe = very wide spectrum but serious AE = seizures

130

Which CMV drug is a pyrophosphate analog?

Foscarnet

131

Which aminopenicillin has the greatest oral bioavailability?

amOxicillin (greater Oral) than ampicillin

132

What is the MOA of sulfa drugs?

They are PABA antimetabolites that inhibit dihydropteroate synthase

134

What 7 bugs are covered by aminopenicillins that are not by penicillins?

Haemophilus influenzae b, E. coli, Listeria, Proteus, Salmonella, Shigella, and Enterococci (HELPSS kill enterococci)

135

What is the most important AE of carbapenems?

Seizures! Use is therefore limited to serious drug rxns

137

Which type of antibiotics is aztreonam synergistic with?

aminoglycosides

138

What inhibits the uptake of tetracyclines?

Divalent cations: milk, antacids, or iron

139

What may relieve the bone marrow issues of trimethoprim?

Leucovorin = same as rescue for methotrexate (folinic acid)

140

Which type of bugs can vancomycin be used against?

GRAM POSITIVE ONLY

141

Name the 3 NNRTI's

Nevirapine, Efavirenz, and Delavirdine

143

Which drugs all end in -navir?

Protease inhibitors

144

In which generation of cephalosporins do you lose gram positive coverage?

3rd (ceftriaxone, cefotaxime, and ceftazidime)

145

Is it safe to give cephalosporins in a penicillin allergic patient?

yes there is low cross-reactivity between the two

146

What are the AE of penicillins (2)?

Hypersensitivity reactions and Hemolytic anemia

147

This TB drug has an unknown MOA but may acidify the intracellular environment by forming _____________

Pyrazinamide; pyrazinoic aci

147

How do you treat life-threatening malaria?

Quinidine (quinine in places outside US)

149

What are 3 mechanisms of resistance to sulfa drugs?

Increased PABA production to outcompete, alteration of dihydropteroate synthase, or decreased uptake

150

Which drug is used to Tx the hypnozoites of Plasmodium vivax malaria?

Primaquine

151

Which antifungal binds ergosterol but is only available topically? Which is used systemically?

Nystatin; Ergosterol

152

What is the mechanism of resistance to ganciclovir?

mutated CMV DNA polymerase or viral kinase

153

Which drugs are indicated for both influenza A and B?

Neuraminidase inhibitors = oseltamavir and zanamavir

154

What bugs are covered by first generation cephalosporins?

Gram positives and Proteus, E. coli, and Klebsiella (PeCK)

156

What is Terbinafine? Terbutaline?

Terbinafine is an antifungal that inhibits squalene epoxidase and is used to Tx dermatophytes; Terbutaline is a B2 agonist used to relax the uterus

157

MOA of nystatin

Binds ergosterol to form membrane pores in fungi; unlike amphotericin B, only available topically because too toxic

158

Which generation of cephalosporins covers gram positive bacteria and Proteus, E. coli, Klebsiella, Haemophilus, Enterobacter, and Neisseria?

Second Generation (HEN PEcK)

159

MOA of foscarnet

Pyrophosphate analog that inhibits CMV viral DNA polymerase

160

Which antibiotic is best for anaerobes above the diaphragm?

Clindamycin

161

What is the mechanism of resistance to acyclovir?

mutation of viral thymidine kinase

163

Name 2 antipseudomonals

Ticarcillin and Piperacillin

163

What are the AE of ganciclovir?

BONE MARROW AND KIDNEY (renal toxicity, leuko, neutro, thrombocytopenia)

164

What 5 types of drugs block protein synthesis at the 50 S ribosomal subunit?

Chloramphenicol, Macrolides, Clindamycin, Streptogramins, and Linezolid

166

Which drug is indicated to treat Hep C and RSV?

Ribavirin

167

How are NNRTI's different from NRTI's?

They bind to reverse transcriptase at a different site than the NRTI's

168

What is the MOA of the azoles for antifungal therapy? How is it different from terbenafine?

Inhibition of the CYP450 that converts lanosterol to ergosterol; Terbenafine inhibits squalene epoxidase which converts squalene to lanosterol

170

What is the mechanism of resistance to chloramphenicol?

Plasmid-encoded acetyltransferase that inactivates it

171

Which electrolytes need to be supplemented when on amphotericin B?

K and Mg

172

Which azole is best for chronic suppression of cryptococcal meningitis?

Fluconazole

174

How can bacteria become resistant to fluoroquinolones?

mutation in DNA gyrase, plasmid mediated resistance, efflux pumps

175

This TB drug blocks DNA dependent RNA polymerase

Rifampin

176

What 2 bugs can TMP-SMX prophylax against in an AIDS patient? Azithromycin?

TMP-SMX = Pneumocystis when CD4

177

What is sodium stibogluconate used to Tx?

Leishmaniasis

178

How do you prevent neurotoxicity in a patient on isoniazid?

Pyridoxine (B6)

180

Why do you avoid ribavirin in pregnancy?

Teratogenic

181

Which aminoglycoside is commonly used for bowel surgery?

Neomycin

182

Which drugs block mRNA synthesis?

Rifampin

183

What is the difference between acyclovir and ganciclovir?

Not much really, both are guanosine analogs that are monophosphorylated by a viral kinase HOWEVER, ganciclovir is more effective against CMV and acyclovir is more effective against HSV

185

Compare the AE of penicillins to the penicillinase-resistant penicillins

Regular penicillins = hypersensitivity and hemolytic anemia whereas Penicillinase resistant ones are allergic rxns and interstitial nephritis

186

What is the AE of flucytosine?

Bone Marrow Suppression

187

Which NRTI does NOT have to be activated?

Tenofovir

189

Why do you avoid griseofulvin in pregnancy?

Teratogenic

190

The AE of which drug can be largely prevented by administration of histamines and a slow infusion rate?

Vancomycin (red man syndrome)

191

Which drug, related to ganciclovir, is a prodrug with better bioavailability?

Valganciclovir

192

Methylation of the 23S rRNA binding site confers resistance to __________

Macrolides but not telithromycin (a ketolide)

193

What is used to treat VRE?

Streptogramins (quinupristin and dalfopristin)

194

Which form of malaria is resistant to chloroquine?

P. falciparum--Tx with artemether/lumifantrine or atovaquone/proguanil

195

Why do you avoid fluoroquinolones in pregnancy?

Cartilage damage

196

What is pyrimethamine used to treat?

Toxoplasmosis

197

What is the MOA of aztreonam?

Monobactam that prevents peptidoglycan crosslinking by binding to PBP3

198

What are ticarcillin and piperacillin used for?

Antipseudomonal penicillins

199

Which drug is used against cryptococcus and is converted to 5-FU by cytosine deaminase?

Flucytosine

200

Which gene encodes HIV-1 protease?

pol gene

201

DOC for Trypanosoma cruzi

Nifurtimox

202

What kind of bacteria are aminoglycosides most effective against?

gram negative

203

What drug is impenem always adminstered with and why?

Cilastatin to decrease renal dehydropeptidase I? This would inactivate imipenem

204

What is special about tenofovir when compared to other NRTI's?

Does not have to be activated

205

What makes nafcillin, oxacillin, and dicloxacillin resistant to beta lactamases?

They have a bulky R group which sterically hinders them

206

Which type of beta-lactam have seizures as an AE?

Carbapenems

207

In which circumstance could you use foscarnet in a ganciclovir resistant strain of CMV?

If the resistance is from lack of viral kinase. Foscarnet does not require viral kinase, however, if the resistance is from viral DNA pol then neither will work

208

What is the AE of terbinafine? What is it used to treat?

abnormal LFTs; used to treat onychomycosis

209

Which bactericidal antibiotics inhibit formation of the initiation complex and cause misreading of mRNA?

aminoglycosides

210

How do you prophylax against syphilis?

Benzathine penicillin G

211

How can you reduce the nephrotoxicity of amphotericin B?

HYDRATE

212

How do you prophylax against gonorrhea?

Ceftriaxone

213

Which antifungal deposits in keratin-containing tissues?

Griseofulvin

214

What is the common toxicity of all CMV drugs?

Nephrotoxicity

215

Which drugs inhibit 50 S and prevent translocation?

Macrolides

216

Which bacteria are not affected by aztreonam?

Gram positive and Anaerobes (Dr. Randolf: Aztreonam is the atom bomb of gram negatives)

217

Which carbapenem does not require coadministration of cilastatin? What does this mean?

Meropenem, it is not degraded in kidneys by dehydropeptidase I

219

How do you prophylax against group B strep in a carrier pregnant female?

Ampicillin (intrapartum)

220

Which 30S inhibitors are bacteriostatic and bactericidal?

Bactericidal = aminoglycoside; Bacteriostatic = tetracyclines

221

Which drugs inhibit fungal cell wall synthesis by inhibiting B-glucan?

Caspofungin and Anidulfungin

222

What is the MOA of raltegravir?

inhibits HIV integrase

223

What is the MOA of ribavirin?

inhibits synthesis of guanine nucleotides by inhibiting IMP dehydrogenase

224

What is the DOC for toxoplasmosis? Prophylaxis in AIDS?

Pyrimethamine; TMP-SMX when CD4 less than 100

225

What are the AE of the penicillinase-resistant penicillins?

Hypersensitivity reactions and Interstitial nephritis

226

Which drug that treats anaerobes blocks peptide transfer at 50S?

clindamycin

227

What molecule is truly a "quinolone"?

nalidixic acid --all others are FLUOROquinolones

228

What are the penicillinase resistant penicillins?

Nafcillin, Oxacillin, and Dicloxacillin

229

Why do you avoid sulfonamides in pregnancy?

Potential for kernicterus

230

What kind of drugs are ampicillin and amoxicillin?

AMINOpenicillins