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Antimicrobials Flashcards

1
Q

Define beta-lactams

A

Antibiotics that contain a beta-lactam ring in their molecular structure

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2
Q

Name the 4 types of penicillins

A

Natural
Anti-staphylococcal
Aminopenicillins
Antipseudomonal

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3
Q

Name 2 natural penicillins

A

Penicillin G
Penicillin V

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4
Q

Name 3 anti-staphylococcal penicillins

A

Oxacillin
Nafcillin
Dicloxacillin

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5
Q

Name 2 aminopenicillins

A

Amoxicillin
Ampicillin

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6
Q

Name 2 antipseudomonal penicillins

A

Piperacillin
Ticarcillin

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7
Q

Name the 4 carbapenems

A

Imipenem
Meropenem
Ertapenem
Doripenem

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8
Q

Name a monobactam

A

Aztreonam

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9
Q

Give examples of 1st generation cephalosporins

A

Cefadroxil
Cefalexin
Cefazolin
Cefazedone

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10
Q

Give examples of 2nd generation cephalosporins

A

2nd graders wear fake fox fur to tea parties

Cefaclor
Cefoxitin
Cefuroxime
Cefotetan

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11
Q

Give examples of 3rd generation cephalosporins

A

Cefixime
Ceftriaxone
Cefdinir
Cefodizine
Cefotaxime
Ceftazadime

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12
Q

Give examples of 4th generation cephalosporins

A

Cefepime
Cefquinome

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13
Q

Give examples of 5th generation cephalosporins

A

Ceftaroline
Ceftobiprole
Ceftolozane

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14
Q

Are beta-lactams bactericidal/bacteriostatic?

A

Bactericidal

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15
Q

Discuss the mechanism of action of beta-lactams

A
  1. Inhibit cell wall synthesis
    - mimics D-ala-D-ala structure of bacterial peptidoglycan residue
    - irreversibly binds to PBPs which act as transpeptidases -> stalled peptidoglycan cross linking -> inability to synthesize new cell wall -> bacterial death
  2. Activate autolytic enzymes
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16
Q

Which beta lactams have good CNS penetration?

A

Ceftriaxone
Aztreonam

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17
Q

When could beta-lactams other than ceftriaxone and aztreonam have CNS penetration?

A

Inflammation of the meninges -> disruption of the blood-brain-barrier

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18
Q

How are beta-lactams excreted?
Name exceptions.

A

Primarily renal
Exceptions
- nafcillin (biliary)
- anti-staphylococcal penicillins (renal and biliary)
- ceftriaxone (renal and biliary)

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19
Q

Name potential adverse effects of beta-lactams

A

Hypersensitivity reactions
Jarisch-Herxheimer reaction (syphilis)

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20
Q

Which organisms usually produce beta-lactamases?

A

Gram negative
Anaerobic

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21
Q

Give examples of beta lactamase inhibitors

A

Clavulanate
Avibactam
Sulbactam
Tazobactam

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22
Q

What is the other name for penicillin G?

A

Benzylpenicillin

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23
Q

What are the forms of penicillin G?

A

IV - crystalline penicillin
IM - procaine penicillin, benzathine penicillin

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24
Q

What is the other name for penicillin V?

A

Phenoxymethylpenicillin

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25
What is the spectrum of cover of natural penicillins?
Gram +ve aerobes Gram -ve cocci Spirochetes Branching gram +ve anaerobes
26
Name adverse effects of natural penicillins
Hypersensitivity reactions Hemolytic anemia Drug-induced interstitial nephritis Seizures
26
How can natural penicillins
Penicillins bind to the bacterial breakdown products that form haptens -> formation of antibodies (anti-IgG) that trigger hemolysis with a positive direct Coombs test
27
Name the mechanisms of penicillin resistance
Penicillinases PBP mutations
27
Name penicillinase-resistant penicillins
Nafcillin Dicloxacillin Oxacillin Floxacillin Methicillin
27
Why is methicillin no longer adminstered?
High rate of side effects
27
What characteristics of penicillinase-resistant penicillins allow them to be intrinsically beta-lactamase resistant?
Addition of bulky side chains e.g. isoxazolyl which prevent the beta-lactam ring from being hydrolysed
28
The penicillinase-resistant penicillins are broad/narrow spectrum?
Narrow spectrum
29
Name the mechanisms of resistance to penicillinase-resistant penicillins
Alteration of PBP binding site
30
Which aminopenicillin has a greater oral bioavailability?
Amoxicillin > ampicillin
31
What is the spectrum of cover of aminopenicillins?
"Extended-spectrum penicillin" Gram +ve aerobes Gram -ve bacilli
32
Which gram -ve bacilli are aminopenicillins not effective against?
Enterobacter spp.
33
Name adverse effects of aminopenicillins
Diarrhea Pseudomembranous colitis Drug-induced rash (incorrectly diagnosed infectious mononucleosis) Hypersensitivity reactions Acute interstitial nephritis (rare)
34
What is the mechanism of resistance to aminopenicillins?
Penicillinases
35
What kind of antipseudomonal penicillin is piperacillin?
Ureidopenicillin (IV)
36
What kind of antipseudomonal penicillin is mezlocillin?
Ureidopenicillin (IV)
37
What is the spectrum of cover of antipseudomonal penicillins?
Gram -ve rods Anaerobes Gram +ve aerobes
38
Which gram +ve aerobe are antipseudomonal penicillins not effective against?
S. viridans
39
Which drug is usually added with imipenem and why?
Cilastatin Inhibits dehydropeptidase, a renal tubular enzyme that metabolizes imipenem
39
What is the spectrum of cover of carbapenems
Gram +ve cocci Gram -ve bacilli Anaerobes
39
Which carbapenem has limited activity against pseudomonas?
Ertapenem
40
Which gram +ve cocci are intrinsically resistant to carbapenems?
MRSA Enterococcus faecalis Enterococcus faecium
41
Name adverse effects of carbapanems
Secondary fungal infections CNS toxicity GI upset Rash Thrombophlebitis
42
Which carbapenems carry the highest and lowest risk of CNS toxicity?
Highest risk - imipenem Lowest risk - meropenem
43
Name bacteria that commonly produce carbapenemases
Keep Every Antibiotic, Protect Every Carbapenem! Klepn Ecoli Aciba Pseae Enterobacter Citfr
44
What are the special characteristics of aztreonam?
Bind to PBP3 Less susceptible to beta-lactamases
45
What is the spectrum of cover of monobactams?
Gram -ve bacteria Can add vanco/clinda to create broad-spectrum coverage
46
Which beta-lactams are an alternative for penicillin allergic patients?
Monobactams (no cross sensitivity)
47
Name adverse effects of monobactams
GI upset Injection reactions Rash
48
Which generation of cephalosporins has the least activity against gram +ve bacteria?
3rd generation
49
Which gram -ve bacteria are covered by 1st generation cephalosporins?
Proteus mirabilis E.coli Klepn 1 PEcK
50
Which gram -ve bacteria are covered by 2nd generation cephalosporins?
Haem influenza Enterobacter aerogenes Neisseria Serratia Proteus mirabilis E.coli Klebs pneumo 2 HENS PEcK
51
Which generation of cephalosporins is active against MRSA?
5th generation
52
Which generation of cephalosporins is active against listeria?
5th generation
53
Which generation of cephalosporins is active against enterococcus?
5th generation
54
Which generation of cephalosporins is active against pseudomonas?
3rd and 4th generation
55
Name adverse effects of cephalosporins
1. Penicillin allergy cross reactivity 2. Autoimmune hemolytic anemia 3. Vitamin K deficiency 4. Disulfiram-like reaction 5. Increases aminoglycoside nephrotoxic effect 6. Neurotoxicity 7. Hyperbilirubinemia (neonates)
56
What is the mechanism of hypoprothrombinemia secondary to cephalosporin use?
Not fully understood Theories: - inhibit growth of vitamin K producing intestinal bacteria - inhibit enzymes of vitamin K metabolism
57
Explain drug-induced autoimmune hemolytic anemia
Drugs bind to RBC membrane proteins -> preformed anti-drug antibodies bind to drug-coated RBCs -> hemolysis in the spleen
58
What are the mechanisms of resistance to cephalosporins?
Cephalosporinase PBP changes
59
Why are cephalosporins (1st-4th generation) LAME?
Ineffective against: Listeria Atypicals MRSA Enterococci
60
Are glycopeptides bactericidal/bacteriostatic?
Bactericidal
61
Which organism are glycopeptides bacteriostatic against?
C. diff
62
Give examples of glycopeptides
Vancomycin Bacitracin Teicoplanin Telavancin Dalbavancin Oritavancin
63
What is the route of elimination of glycopeptides?
Renal via glomerular filtration
64
What is the spectrum of cover of glycopeptides?
Gram +ve bacteria MRSA S. epidermidis Enterococci C. diff
65
Name adverse effects of glycopeptides
Nephrotoxicity Ototoxicity Thrombophlebitis Vancomycin flushing reaction DRESS syndrome Neutropenia Dysgeusia GIT upset
66
What is vancomycin flushing reaction?
Anaphylactoid reaction caused by rapid infusion of vancomycin -> nonspecific mast cell degranulation -> rapid histamine release
67
Which kind of vancomycin therapy is associated with neutropenia?
Prolonged (>7 days)
68
What does DRESS syndrome stand for?
Drug reaction with eosinophilia and systemic symptoms
69
Name contraindications for glycopeptides
Pregnancy
70
Name mechanisms of resistance to glycopeptides
Modification of D-ala-D-ala to D-ala-D-lac (mainly enterococcus)
71
What is the mechanism of action of epoxides?
Inhibits enolpyruvate transferase (MurA) -> no formation of N-acetylmuramic acid -> inhibition of cell wall synthesis
72
Epoxides are bactericidal/bacteriostatic?
Bactericidal
73
Name an epoxide
Fosfomycin
74
What is the route of elimination of fosfomycin?
Renal
75
Name adverse effects of fosfomycin
Mild electrolyte imbalances (hypernatremia, hyopkalemia) Diarrhea
76
What is the mechanism of resistance to fosfomycin?
MurA mutations
77
Give an example of a lipopeptide
Daptomycin
78
What is the mechanism of action of daptomycin?
Incorporates K+ channels into the cell membrane of gram +ve bacteria -> rapid membrane depolarization -> loss of membrane potential -> inhibition of DNA, RNA and protein synthesis
79
Daptomycin is bactericidal/bacteriostatic?
Bactericidal
80
What is the route of elimination of daptomycin?
Renal
81
What is the spectrum of cover of daptomycin?
Gram +ve bacteria MRSA VRE
82
What are the main sites in the body that daptomycin is effective?
Skin Blood Heart
83
Why can daptomycin not be used for pneumonias?
It is bound and inactivated by surfactant
84
Name adverse effects of daptomycin
Reversible myopathy Rhabdomyolysis Allergic pneumonitis
85
What is the mechanism of resistance to daptomycin?
Repulsion of daptomycin molecules due to change in bacterial surface charge
86
Give examples of polymyxins
Polymyxin E = colistin Polymyxin B
87
What kind of molecule are polymyxins?
A cationic detergent (polypeptide) molecule
88
What is the mechanism of action of colistin?
Binds to phospholipids (LPS endotoxin) of the cytoplasmic membrane of gram -ve bacteria -> increase membrane permeability -> leakage of cell contents
89
What is the route of elimination of colistin?
Renal
90
How can polymyxin B be used for superficial skin infections?
Triple antibiotic ointment - bacitracin - neomycin - polymyxin B
91
How can polymyxin B be used to prevent ICU infections?
May be used to disinfect the bowel
92
Name adverse effects of colistin
Nephrotoxicity Neurotoxicity Anaphylactoid reactions Respiratory failure
93
Give examples of aminoglycosides
Gentamycin Amikacin Tobramycin Streptomycin Neomycin Capreomycin Kanamycin
94
What is the mechanism of action of aminoglycosides?
Bind to 30S subunit of bacterial ribosome -> irreversible inhibition of initiation complex -> inhibition of bacterial protein synthesis
95
With which drug class are aminoglycosides synergistic?
Beta-lactams inhibit cell wall synthesis to facilitate entry of aminoglycoside drugs into the cytoplasm
96
What is the route of elimination of aminoglycosides?
Renal via glomerular filtration
97
What is the spectrum of cover of aminoglycosides?
Gram -ve bacilli
98
Why are aminoglycosides not effective against anaerobes?
Require oxygen to be absorbed by cells
99
Name adverse effects of aminoglycosides
Nephrotoxicity Ototoxicity Vestibulotoxicity Neuromuscular blockade Teratogenecity
100
Concurrent use with which drugs increase the risk of ototoxicity secondary to aminoglycoside use?
Loop diuretics
101
Name contraindications for aminoglycosides
Myasthenia gravis Botulism Pregnancy
102
What are the mechanisms of resistance to aminoglycosides?
Bacterial transferase enzyme inactivation via - acetylation - phosphorylation - adenylation
103
Give examples of tetracyclines
Minocycline Tetracycline Doxycycline Demeclocyline
104
What is the mechanism of action of tetracyclines?
Bind 30s subunit -> aminoacyl-tRNA is blocked from binding to ribosome acceptor site -> inhibition of bacterial protein synthesis
105
Are tetracyclines bactericidal/bacteriostatic?
Bacteriostatic
106
What is the route of elimination of tetracyclines?
Renal
107
Which tetracycline is not contraindicated in patients with renal failure and why?
Doxycycline - only gastrointestinal elimination
108
What is the spectrum of cover of tetracyclines?
Atypical bacteria Community-acquired MRSA
109
Which substances should oral tetracyclines not be taken with and why?
Any substance containing large amounts of divalent cations which inhibit intestinal absorption of tetracyclines
110
Name adverse effects of tetracyclines
Hepatotoxicity Teeth and bone changes Mucous membrane damage (esophagitis) Photosensitivity Fanconi syndrome Pseudotumor cerebri
111
Why do tetracyclines cause photosensitivity?
Tetracyclines absorb UV radiation -> photochemical reaction -> free radical formation -> damage to cellular components -> inflammation
112
Give contraindications to tetracyclines
Children <8yo Pregnant/breastfeeding women Renal failure Hepatic dysfunction
113
What is the mechanism of resistance to tetracyclines?
Plasmid-encoded efflux pumps
114
Give an example of a glycylcycline
Tigecycline
115
What is the mechanism of action of tigecycline?
Binds to 30S subunit -> blockage of entry of amino-acyl tRNA into ribosomal A site -> inhibition of protein synthesis
116
What is the route of elimination of tigecycline?
Mostly biliary
117
What is the spectrum of cover of tigecycline?
Gram positive aerobes Gram negative aerobes MRSA VRE Anaerobes Non-gram staining bacteria
118
Which gram positive aerobes is tigecycline not effective against?
S. viridans Enterococci MSSA
119
Which gram negative aerobes is tigecycline not effective against?
Proteus
120
Name adverse effects of tigecycline
GI upset Hepatotoxicity Teeth and bone deposition Photosensitivity
121
What are the contraindications to tigecycline?
Children <8yo Pregnant/breastfeeding women Hepatic dysfunction
122
Give examples of macrolides
Erythromycin Azithromycin Clarithromycin Roxithromycin
123
What is the mechanism of action of macrolides?
Bind to 23S ribosomal RNA molecule of 50S subunit -> blockage of translocation -> inhibition of bacterial protein synthesis
124
What is the route of elimination of macrolides?
Biliary
125
What is the spectrum of cover of macrolides?
Atypical pneumonias Bordetella Chlamydia Gram +ve cocci Neisseria Mycobacterium avium (azithro) H. pylori Ureaplasma urealyticum Babesia spp. (azithro + atovaquone)
126
Name adverse effects of macrolides
Increased intestinal motility QT prolongation Arrythmias Acute cholestatic hepatitis Eosinophilia Rash HPS risk in infant <6w
127
Which drugs does erythromycin interact with?
All affected by CYP450
128
Which macrolide does not have a short half life?
Azithromycin
129
What can erythromycin be used off label for?
Gastroparesis (increases intestinal motility)
130
Which macrolides are contraindicated in pregnant women?
Erythromycin estolate Clarithromycin
131
What is erythromycin estolate use in pregnant women during the 1st trimester associated with?
Hepatic failure
132
Can erythromycin forms other than erythromycin estolate be used in pregnant women?
Yes (ethyl succinate, stearate)
133
Which macrolide must be used cautiously in patients with renal failure?
Clarithromycin
134
What is the mechanism of resistance to macrolides?
Methylation of the binding site of 23S rRNA -> macrolide cannot bind to rRNA
135
What bacterial class is clindamycin?
Lincosamides
136
What is the mechanism of action of clindamycin?
Binds to 50s subunit to block peptide translocation -> inhibition of peptide chain elongation -> inhibition of bacterial protein synthesis
137
What the route of elimination of clindamycin?
Renal and biliary
138
What is the spectrum of cover of clindamycin?
Anaerobes Gram +ve aerobes Babesia (with quinine)
139
What does clindamycin share cross resistance with?
Macrolides
140
Name adverse effects of clindamycin
GI upset Pseudomembranous colitis Fever Teratogenicity
141
Give examples of streptogramins
Dalfopristin Quinupristin
142
What is the mechanism of action of dalfopristin?
Binds to 23S portion of 50S subunit -> change conformation -> enhanced binding of quinupristin and inhibits peptidyl transferase
143
What is the mechanism of action of quinupristin?
Binds to 50S subunit -> prevents elongation of polypeptide -> incomplete chains released
144
What is the route of elimination of streptogramins?
Biliary and renal
145
What is the spectrum of cover of streptogramins?
Skin infections - staph - strep - VRE
146
Which enterococcus are streptogramins NOT effective against?
Enterococcus faecalis
147
Which cytochrome is inhibited by streptogramins?
CYP3A4
148
Name adverse effects of streptogramins
GI upset Headache Arthralgia Myalgia Thrombophlebitis Pseudomembranous colitis Pruritis (rare)
149
Has safety been establish for streptogramins in pregnant/breastfeeding women or children <16yo?
No
150
Name mechanisms of resistance to streptogramins
Modification of ribosome binding site Enzyme-mediated methylation Efflux pumps
151
Which drug class does linezolid belong to?
Oxazolidinones
152
What is the mechanism of action of linezolid?
Binds to 23S RNA of 50S subunit -> inhibition of initiation complex formation -> inhibition of bacterial protein synthesis Non-selective MAOI
153
Against which bacteria is linezolid bactericidal?
Streptococci
154
What is the CNS penetration of linezolid?
Good
155
What is the route of elimination of linezolid?
Hepatic metabolism Biliary and renal elimination
156
Name adverse effects of linezolid
GI upset Pancytopenia Peripheral neuropathy Serotonin syndrome
157
Give contraindications for linezolid
SSRIs Selective MAOIs
158
Name mechanism of resistance to linezolid
Point mutation of 23S rRNA
159
What is the mechanism of action of chloramphenicol?
Binds to 50S subunit -> blockage of peptidyltransferase -> inhibition of bacterial protein synthesis
160
What is the CNS penetration of chloramphenicol?
Good
161
What is the route of elimination of chloramphenicol?
Hepatic metabolism Renal elimination
162
What is the spectrum of cover of chloramphenicol?
Meningitis Rickettsia
163
Which cytochromes does chloramphenicol inhibit?
CYP2C19 CYP3A4
164
Name adverse effects of chloramphenicol
Dose dependent BM suppression Gray baby syndrome
165
What is the mechanism of resistance in chloramphenicol?
Drug inactivation via plasmid-encoded acetyltransferase
166
Give examples of 1st generation fluoroquinolones
Nalidixic acid
167
Give examples of 2nd generation fluoroquinolones
Ciprofloxacin Norfloxacin Ofloxacin Enoxacin
168
Give examples of 3rd generation fluoroquinolones
Levofloxacin
169
Give examples of 4th generation fluoroquinolones
Moxifloxacin Gemifloxacin Gatifloxacin
170
Which is the only fluoroquinolone also available in IV form?
Levofloxacin Enoxacin
171
What is the mechanism of action of fluoroquinolones?
Inhibition of prokaryotic topoisomerase II and IV -> DNA supercoiling -> formation of double-stranded breaks -> inhibition of DNA replication and transcription
172
What is the CNS penetration of fluoroquinolones?
Good
173
What is the route of elimination of fluoroquinolones?
Renal via glomerular filtration and tubular secretion
174
Which fluoroquinolone undergoes biliary excretion?
Moxifloxacin
175
Which substances reduce fluoroquinolone absorption?
Polyvalent cations
176
Name the "respiratory" fluoroquinolones
Levofloxacin Moxifloxacin Gemifloxacin
177
What is the spectrum of cover of the non-respiratory fluoroquinolones?
Gram -ve rods (urinary, GI) Genitourinary infections (gonorrhoeae, chlamydia, ureaplasma)
178
Which flouroquinolone is effective against pseudomonas?
Ciprofloxacin
179
What is the spectrum of cover of the respiratory fluoroquinolones?
Atypical bacteria Anaerobes
180
Which fluoroquinolone is highly potent against penicillin-resistant pneumococci?
Gemifloxacin
181
Name adverse effects of fluoroquinolones
GI upset Neurological Hypo/hyperglycemia QT prolongation Photosensitivity Superinfection Tendon rupture Life threatening exacerbation of myasthenia gravis
182
What neurological adverse effects can be caused by fluoroquinolones?
Headache Dizziness Mood changes Peripheral neuropathy Lower seizure threshold
183
Which factors increase risk for lower seizure threshold with fluoroquinolones?
NSAID use Prev epilepsy hx
184
Which cytochrome do fluoroquinolones inhibit?
CYP450
185
Name mechanisms of resistance to fluoroquinolones
Chromosome encoded mutations in DNA gyrase and topoisomerase IV enzymes Altered cell wall permeability Plasmid-encoded mutations in efflux pump proteins
186
Give examples of nitroimidazoles
Metronidazole Tinidazole
187
What is the mechanism of action of metronidazole?
Creates free radicals within bacterial cell -> DNA strand breakage -> cell death
188
What is the CNS penetration of metronidazole?
Good
189
What is the route of elimination of metronidazole?
Renal
190
What is the spectrum of cover of metronidazole?
Some protozoa (giardia, tricho, entamoeba) Anaerobes Facultative anaerobes
191
Name adverse effects of metronidazole
Headache Metallic taste Peripheral neuropathy Vestibular dysfunction
192
Can nitroimidazoles cause disulfiram-like reactions?
Disproved despite case reports Metronidazole does not inhibit acetaldehyde dehydrogenase Possible explanations - change in gut flora, histamine reactions
193
Give examples of diaminopyrimidine derivatives
Trimethoprim Pyrimethamine
194
Give examples of antibiotic sulfonamides
Sulfamethoxazole Sulfadiazine Sulfisoxazole
195
Give examples of non-antibiotic sulfonamides
Diuretics (thiazides, furosemide, acetazolamide) Anti-inflammatory drugs (celecoxib) Sulfonylureas Probenecid
196
What is the mechanism of action of trimethoprim versus sulfamethoxazole?
Both inhibit bacterial folic acid synthesis Trimethoprim - inhibits dihydrofolate reductase (DHFR) Sulfamethoxazole - inhibits dihydropteroate synthase
197
What is the CNS penetration of TMP-SMX?
Good
198
What is the route of elimination of TMP-SMX?
Primarily renal via tubular secretion
199
What is the spectrum of cover of TMP-SMX?
Shigella Salmonella Empiric UTI treatment Prophylaxis (P. jirovecii, toxoplasmosis)
200
What is the spectrum of cover of sulfisoxazole?
Broad spectrum gram +ve and -ve N. meningitidis Chlamydia trachomatis Nocardia asteroides Toxoplasma gondii Plasmodia
201
Name adverse effects of sulfonamides
CYP450 drug interactions Kernicterus (infants) Nephrotoxicity GI upset Hyperkalemia Agranulocytosis Pancytopenia Hemolytic anemia Steven Johnson's Photosensitivity Fever
202
What is the most common form of nephrotoxicity secondary to sulfonamide use?
Acute tubulointerstitial nephritis
203
In which patients can sulfonamides trigger hemolytic anemia?
G6PD-deficiency
204
Name adverse effects of trimethoprim
Megaloblastic anemia Leukopenia Granulocytopenia Hyperkalemia Increased creatinine
205
How does trimethoprim cause hyperkalemia?
Competitive inhibition of ENaC channels in the distal convoluted tubule -> decreased NA reabsorption -> decreased K secretion
206
What are the mechanisms of resistance to sulfonamides?
Mutation in bacterial dihydropteroate synthase Increased PABA synthesis Decreased sulfonamide uptake
207
Which drug class does nitrofurantoin belong to?
Nitrofurans
208
What is the mechanism of action of nitrofurantoin?
Reduced by bacterial nitroreductases to reactive metabolites -> bind to ribosome -> impaired metabolism + synthesis of protein, DNA, RNA -> cell death
209
What is the route of elimination of nitrofurantoin?
Primarily renal Minimal in the feces
210
What is the spectrum of cover of nitrofurantoin?
UTI pathogens (gram +ve and -ve)
211
Which UTI pathogens is nitrofurantoin NOT effective against?
Pseudomonas Proteus
212
Can nitrofurantoin be used in pyelonephritis?
No! It does not achieve adequate concentrations in renal tissue.
213
Name adverse effects of nitrofurantoin
Nitrofurantoin-induced lung disease (NILD) Pulmonary fibrosis Hemolytic anemia in G6PD deficiency GI upset Reversible peripheral neuropathy
214
Distinguish between acute vs chronic NILD
Acute = hypersensitivity reaction usually 9 days after exposure Chronic = cell-mediated or toxic reaction usually 6 months after exposure
215
Name contraindications for nitrofurantoin
Children <1mo Breastfeeding women Women GA 38-42w Hepatic dysfunction eGFR <60

Bacteriology (4 decks)

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