antibiotics Flashcards
1
Q
what drugs inhibit the cell wall of bacteria
A
penicillins and their b-lactamase inhibitors
cephalosporins
carbapenems
monobactams
Glycopeptides
2
Q
how do penicillins work
A
their b-lactam ring binds to the PBPs in bacteria to inactivate it = inhibition of transpeptidase = weak cell wall
3
Q
how do bacteria achieve resistance against penicillins
A
because of penicillinases, they cleave the B-lactamic ring on penicillins = they can no longer bind to the PBPs in the cell wall
4
Q
how does MRSA gain resistance
A
MRSA has a mecA gen mutation for their PBPs = PBP2A = b-lactam rings are unable to bind to it
5
Q
do b-lactams cover MRSA?
A
no, with the exception of Ceftaroline
6
Q
what are the subdivisions of penicillins
A
classic penicillins: V and G
penicillinase resistant penicillins
aminopenicillins
antipseudomonal penicillins
7
Q
what do classic penicillins cover
A
gram positives ★★
gram negatives ★
use: streptococcal pharyngitis, syphilis, actinomycosis
(S. pyogenes, T. pallidum, actinomyces israelli)
8
Q
adverse effects of classic penicillins
A
- hypersensitivity reactions → immediate and delayed = type 1 and 4
- hemolytic anemia → penicillin can bind to the RBC membrane causing it’s destruction by complement
- tubulointerstitial nephritis → eosinophilia and rash + ⭡creatinin ⭡BUN (blood urea nitrogen)
- tubulointerstitial nephritis + hemolytic anemia = mycoplasma → BUT NO EOSINOPHILIA
- same mechanism as hemolytic anemia
9
Q
whats the treatment for syphilis
A
penicillin G
10
Q
whats the treatment for actinomycosis
A
penicillin G
11
Q
whats the treatment for pneumococcal meningitis
A
vancomycin + 3rd gen cephalosporin (+ dexamethasone)
12
Q
whats the treatment for sensitive S. pneumoniae
A
penicillin G
13
Q
whats the treatment for Streptococcus pyogenes
A
penicillin V (+ clindamycin to decrease toxin production)
14
Q
what are the Penicillinase-resistant penicillins
A
nafcillin, dicloxacillin, oxacillin, floxacillin, methicillin
15
Q
whats the use for Penicillinase-resistant penicillins
A
cellulite, osteomyelitis, endocarditis (MSSA)
16
Q
what Penicillinase-resistant penicillins do you use for MSSA
A
meticillin
17
Q
names of aminopenicillins
A
amoxicillin and ampicillin
18
Q
do you combine aminopenicillins with anything?
A
amoxicillin with clavulanate
ampicillin with sulbactam
19
Q
whats the coverage of aminopenicillins
A
-gram positive ★★(★)
gram negative ★★
use: upper respiratory infections, otitis media, sinusitis, cellulitis, UTI
- h. influenzae, h. pylori, listeria, e. coli, enterococci
can be used as part of the empiric treatment for meningitis = + ceftriaxone and vancomycin in very young or old patients, or in inmunocompromissed or pregnant ones
20
Q
adverse effects of aminopenicillins
A
pseudomembranous colitis, hypersensitivity reactions
21
Q
whats the treatment for community acquire pneumonia if the bacteria is sensible to penicillins
A
amoxicillin
22
Q
what are the Antipseudomonal penicillins
A
piperacillin and ticarcillin
23
Q
do you combine antipseudomonal penicillins with anything?
A
piperacillin (+ tazobactam), ticarcillin (+ clavulanate)
24
Q
what do antipseudomonal penicillins cover?
A
gram positives ★★(★)
gram negatives ★★★
use: hospital acquired pneumonia, severe soft tissue infections (diabetic ulcers), intra-abdominal infections
additional coverage: pseudomonas, anaerobes
25
what are the adverse reactions to antipseudomonal penicillins
hemolytic anemia, thombocytopenia, DRESS sindrome
26
what are the 1st gen cephalosporins
Cephalexin, Cefazolin, Cefalotin
Cefa- alex zol lotin
"alex solo lotina"
27
what are the second gen cephalosporins
Cefaclor, Cefuroxime, Cefoxitin
cef- aclor, uroxime , oxitin
"A-U-O a-cloro xime oxitina"
****cefotetan
28
what are the third gen cephalosporin
Ceftriaxone, Cefotaxime, Ceftizoxime, Cefixime, Ceftazidime
ceftriaxone
+
-ximes (with the exception of cefuroxime which is a 2nd gen)
-> cefota, ceftrizo, cefi
29
what are 4th gen cephalosporins
Cefepime, Cefpirome, Cefpiramide
"pi"
cefePIme, cefPIrome, cefPIramide
30
what are 5th gen cephalosporins
Ceftaroline, Ceftobiprole, Ceftolozane
31
what do 1st gen cephalosporins cover
gram positive: ★★★
gram negative: ★
use: skin infections and UTIs
- skin infections → you need to cover staph (MSSA) and strep
- DOSN’T COVER MRSA
- cefazolin is commonly used as a prophylactic antibiotic for surgeries
- UTIs → you cover e.coli, klebsiella, proteus → IMPORTANT IN PREGNANCY
32
what do second gen cephalosporins cover
gram positive: ★★
gram negative: ★★
use: intra-abdominal infections and UTIs
- neisseria, serratia and h. influenza
- additional coverage: anaerobes (cefoxitin, cefotetan)
33
which second gen cephalosporins cover anaerobes and what are they used for
cefoxitin and cefotetan → perioperative prophylaxis for patients undergoing intra abdominal and gynecological surgical procedures
34
therapy of choice for all forms of gonorrhea and for severe forms of Lyme disease
ceftriaxone
35
which 3rd gen cephalosporin covers pseudomonas
ceftadizime
36
overall what's the 3rd gen cephalosporin coverage
gram positive: ★
gram negative: ★★★
use: pneumonia, meningitis, **meningococcal prophylaxis in pregnancy (ceftriaxone)**, late lyme disease, gonococcal infections
**for meiningococcal prophylaxis the most common med is rifampin but this doesn’t apply in pregnancy**
- bad staph coverage (MSSA)
- ceftriaxone has a little coverage por staph and strep, but with ceftadizime you have NO coverage against them
37
what's the preferred profilaxis for meningococcal infections in pregnant and non pregnant people
in pregnancy use ceftriaxone
in other use rifampin
38
coverage of 4th gen cephalosporins
gram positive: ★★★
gram negative: ★★★
use: immunocompromised, hospital-acquired pneumonia, neutropenic fever, complicated UTI
additional coverage: pseudomonas (cefepime)
39
whats the coverage of 5th gen cephalosporins
gram positive: ★★★
gram negative: ★★★
use: immunocompromised, hospital acquired pneumonia, neutropenic fever, complicated STI
additional coverage:
-anaerobes
-MRSA, VRSA, listeria E. faecalis (CEFTAROLINE)
- pseudomonas (ceftolozane - most potent against pseudomonas)
40
most potent cephalosporin against pseudomonas
ceftolozane
41
what cephalosporin covers MRSA and how does it do it
CEFTAROLINE
it doesn’t bind to the catalytic site in PBP, instead it binds in an allosteric site that causes a conformational change in the protein, in that way inactivating the PBP
42
whats the Jarisch-Herxheimer Reaction
an acute self-limited systemic febrile reaction accompanied by headache, myalgia, tachycardia, hyperventilation, and mild hypotension that occurs within 1 to 2 hours and lasts 12 to 24 hours after any effective therapy for syphilis
43
what are the general principles of carbapenems
- bactericidal
- PBPs catalize peptidoglycan cross-linking
- B-lactam binds to PBP (penicillin binding protein)
- there are carbapenemase that create resistance to these antibiotics by cleaving the b-lactam ring
- resistance in MRSA because of the PBP-2A mutation
44
which meds are carbapenems
meropenem, imipenem, ertapenem, doripenem
-PENEM
45
which carbapenems needs to be combines with another med ?
which is it and why?
imipenem (+ cilastatin)
cilastatin prevents imipenem to be broken down in the renal tubular tissue
46
what do carbapenems cover?
gram positive: ★★★
gram negative: ★★★
additional coverage: pseudomonas (except ertapenem), anaerobes, ESBL
use: hospital-acquired infections, intra-abdominal infections, complicated soft tissue infections
47
carbapanems typically cover pseudomonas, only one of them is the exception.
which one is it?
ertapenem
48
what are the adverse effects of carbapenems
seizures (imipenem > meropenem)
rash
acquired fungal infection
49
which type of b-lactam exclusively covers gram negs
monobactams
50
name one monobactam
aztreonam
51
whats the coverage of aztreonam
gram negative: ★★★
use: hospital acquired pneumonia, UTI, intra-abdominal infections (PCN allergy)
no cross reactivity for patients with penicillin allergy !!
52
is there any disruptor of the cell wall that isn't a b-lactam?
yes, glycopeptides = vancomycin and bacitracin
53
is vancomycin bacteriocidal?
it's bactericidal, except for C. difficile in which case is bacteriostatic
54
whats the mechanism of action of vancomycin
it binds D-ala / D-ala in cell wall → block's the PBP from binding to the D-ala residue →⭣peptidoglycan synthesis
55
how do bacteria gain resistance to vancomycin
the vanA gene allows D-alanine to convert into D-lactate → resistance of VRE
56
whats the coverage of vancomycin
gram positive: ★★★
** doesn’t work for gram negatives because of the LPS
use: multi-drug resistant gram positive, pseudomembranous colitis (because of C.difficile = VO vancomycin)
additional coverage: MRSA
57
what's the first line of treatment for pseudomembranous colitis
the 1st line of treatment would be fidaxomicin
58
what adverse effects do vancomycin have?
lushing reaction
DRESS syndrome
nephrotoxic
ototoxic
thrombophlebitis
neutropenia
59
how can you reduce the risk of the red men syndrome (flush reaction - type 1 HS) caused by vancomycin
to reduce the risk of the red men syndrome (flush reaction - type 1 HS), you can either decrease the infusion speed or pre-treat the patient with IV antihistamine (often diphenhydramine)
60
nephrotoxicity and ototoxicity are some of the adverse reactions of vancomycin, there is another medication that has the same effect
what is it ? and can you use them together?
aminoglycosides have these types of toxicity so DONT’T COMBINE THEM
61
whats the mechanism of action of bacitracin
they prevent transport of peptidoglycan precursor units → ⭣peptidoglycan synthesis
62
what's the coverage of bacitracin
gram positive: ★★★ (staph)
use: skin infections
additional coverage: MRSA
63
what drugs inhibit the plasma membrane
daptomycin
polymyxins
64
how does daptomycin work?
Bactericidal
⭡K+ channel into cell membrane → rapid membrane depolarization → loss of membrane potential
65
what's the daptomycin coverage?
gram positive: ★★★
use: skin infections, endocarditis
additional coverage: MRSA, VRE
*** its inactivated in the lungs by surfactant = DOESNT WORK with respiratory infections (pneumonias)
66
what are the adverse effects of dampotycin
myopathy, rhabdomyolisis, darkend urine
67
which are the polymyxins?
polymyxin B, polymyxin E (colistin)
68
how do polymyxins work
bactericidal
binds the phospholipids in cell membrane → ⭡membrane permeability → leakage of cell contents
69
what's the coverage of polymyxins
gram negative: ★★
use: immunocompromised, severe hospital acquired multi-drug resistant infections
additional coverage: pseudomonas
70
what are the side effects of polymyxins
nephrotoxicity, **neurotoxicity**, respiratory insufficiency, hypersensitivity reactions
71
which meds are the protein synthesis inhibitors
aminoglycosides
tetracyclines
Glycylcyclines
macrolides
lincosamides
oxazolidinones
amphenicols
72
which drugs are aminoglycosides
Gentamicin, Amikacin, Neomycin, Kanamycin, Streptomycin
-CIN
73
how to aminoglycosides work
bactericidal
concentration dependent drug
bind to the 30S ribosomal subunit → irreversible inhibition of initiation complex, ⭣translocation, misreading of mRNA → ⭣protein synthesis
** in aerobic bacteria the oxygen can be used to uptake the aminoglycosides (AG) into the bacteria
** that’s why it’s more challenging for the AG to get into an anaerobic bacteria
74
can you combine aminoglycosides with oyher drugs
synergisim with b-lactams → they weaken the cell wall to allow an easier access for aminoglycosides to the cell and ribosome
** this also allows for gram (+) coverage
DONT COMBINE WITH VANCOMYCIN → because of the toxicity
75
whats the coverage of aminoglycosides
gram negative: ★★★
additional coverage: pseudomonas, mycobacterium tuberculosis (streptomycin - more common in the past because of the side effects)
use: severe gram negative infections, endocarditis, bowel surgery preparation (neomycin)
76
how do bacteria develop resistance against aminoglycosides
inactivation via acetylation, adenylation, or phosphorylation (bacterial transferases)
OR
altered 30S ribosomal subunit structure
⭣bactericidal activity
⭡MIC (minimum inhibitory concentration) = you have to give higher doses
77
when a patient has endocarditis and you prescribe an aminoglycoside, do you give it alone?
in combination with b-lactams
78
what are the adverse effects of aminoglycosides
nephrotoxicity, ototoxicity, neurotoxicity, teratogenicity
**more irreversible changes in contrast with vancomycin
79
what are the most commonly used tetracyclines?
Doxycyline and tetracycline
others to keep in mind can be minocycline and demelocycline
80
first line of coverage against atypical bacteria
doxycyline
81
what's the main use of demelocycline
principally use as an ADH (antidiuretic hormone) antagonist (SIADH)
82
how do tetracyclines work?
bacteriostatic
bind to 30S ribosomal subunit → blockage of aminoacyl-tRNA binding → ⭣protein synthesis
83
what's the coverage of tetracyclines
gram positive: ★★★
gram negative ★★
additional coverage:
- MRSA (especially for community acquired - doxycycline)
- atypicals (mycoplasma, ureaplasma, rickettsia, borrelia burgdoferi, freancisella tularensis, chlamydia, brucella, coxiella)
**with atypicals the go to is doxycyline
*** use doxycycline for syphilis when there is an allergy to penicillins
- use: acne and other skin infections, atypical phatogens, **early lyme disease** and lyme profilaxis
84
how do bacteria gain resistance against tetracyclines
transport pumps → ↑ tetracycline efflux
OR
⭣uptake with cell (plasmid encoded)
85
what are the tetracyclines adverse effects
nephrotoxicity (except doxycycline)
hepatotoxicity,
photosensitivity
teratogenicity
tooth discoloration
GI discomfort = doxycycline is eliminated trough the GI tract, thats why it can cause GI discomfort
pill-induced esophagitis
86
are there any contraindications for using tetracylines ?
don’t give to pregnant ladys and children <8 years
** doxycycline is the exception for early lyme disease
** in pregnant women the only exception is with rickettsia
also avoid with divalent cation preparations (iron, antacids)
87
what drug do you give for early lyme disease and lyme prophylaxis
a tetracyline
88
ALL 30S ribosomal inhibitors are bacteriostatic with the EXCEPTION of ....
aminoglycosides
89
the 30S ribosomal inhibitors are
aminoglycosides, tetracyclins, glycylclines
90
what's a tetracycline derivative
Tigecycline
91
how does tigecycline work
bacteriostatic
bind to 30S ribosomal subunit → blockage of aminoacyl-tRNA binding → ⭣protein synthesis
92
what's the coverage of tigercyclines?
gram positive: ★★★
gram negative ★★
additional coverage: MRSA, VRE, anaerobes, atypicals
use: complicated intra-abdominal infections, soft tissue infections
93
what are the adverse effects of tigercyclines
overall ↑ risk of death with severe infections, hepatotoxicity, photosensitivity, tooth discoloration, GI discomfort
94
is there specific instructions for the administration of tigeracycline?
avoid with divalent cation preparations (iron, antacids)
95
principal macrolides
azithromycin, clarithromycin, erythromycin
96
how do macrolides work?
bacteriostatic
bind to 23S ribosomal RNA of 50S ribosomal subunit → ⭣translocation → ⭣ protein synthesis
97
what's the coverage of macrolides
gram positive: ★★
gram negative ★★
additional cover: atypicals
use: community acquired pneumonia (lobar/interstitial), bronchitis, COPD exacerbations, MAC prophylaxis/treatment, STI (chlamydia), PUD (H. pylori)
**community acquired pneumonia = azithromycin + ceftriaxone (to cover strep.)
** STI in pregnant women → azithromycin
98
how do bacteria gain resistance against macrolides
methylation of 23S rRNA binding site
99
what are the macrolide side effects
QT prolongation (erythromycin)
GI discomfort (erythromycin)
hypertrophic pyloric stenosis
hepatotoxicity
+/- teratogenic (erythromycin, clarithromycin)
erythromycin is commonly used as a GI motility agent
hypertrophic pyloric stenosis → common in babys of like 3 weeks whose moms use erythromycin during their pregnancy → the child will get rid of this via nonbilious projectile emesis
100
do macrolides have interactions with other meds?
↑ theophylline
CYP3A4 inhibitor (erythromycin, clarithromycin)
101
for the treatment of patients with gonorrhea and uncertain chlamydia co-infection the ideal treatment is:
ceftriaxone + doxycycline in NON-pregnant patients
ceftriaxone + azithromycin in PREGNANT patients
102
why do you have to cover for chlamydia when you are not sure if the patient has it
because chlamydia only grows intra-cellularly which means you can not detect it in cultures
103
triple therapy for h. pylori infection in patients without penicillin allergies is:
amoxicillin, PPI and clarithromycin
104
how does clindamycin work
bacteriostatic
bind to 23S ribosomal RNA of 50S ribosomal subunit → ⭣translocation → ⭣protein synthesis
105
what's the coverage of clindamycin
gram positive: ★★★
additional coverage: anaerobes, MRSA
use: celullitis, sinusitis, nencrotizing fasciitis, aspiration pneumonia, lung abscess, toxic shock syndrome
NO penetration in the CNS → won’t work with brain abcess, instead use metronidazole
106
adverse effects of clindamycin
pseudomembranous collitis, teratogenicity (especially in the 1st trim)
107
which meds are Oxazolidinones
Linezolid, Tedizolid
108
whats the mehcanisim of action of linezolid?
bacteriostatic in general BUT
bacteriocidal for sreptococci
binds to 23S ribosomal RNA of 50S ribosomal subunit → inhibition of initiation complex formation → ⭣protein synthesis
109
what does linezolid cover
gram positive: ★★★
additional coverage: MRSA, VRE, mycobacterium tuberculosis
use: skin and soft tissue infections
110
adverse effects of linezolid
myelosuppression (thrombocytopenia)
sideroblastic anemia
lactic acidosis
peripheral neuropathy
optic neuritis
** blindness, serotonin syndrome (because it acts as a MAOI)
** it causes mitocondrial toxicity
111
how do bacteria gain resistance against linezolid
point mutations of 23s ribosomal RNA
112
antibiotic associated with blindness and serotonin syndrome
linezolid
113
how does chloramphenicol work
binds to the 50S ribosomal subunit → ⭣peptidyl-transferase → ⭣protein synthesis
114
what are the adverse effects of chloramphenicol
myelosupression
aplastic anemia
sideroblastic anemia
“gray baby syndrome”
teratogenicity
115
how do bacteria gain resistance against chloramphenicol
inactivation via acetyltrasferase (plasmid-encoded)
116
which meds are Fluroquinolones
**Levofloxacin**
**Moxifloxacin**
**Ciprofloxacin**
Nalidixic Acid
Norfloxacin
Ofloxacin
Enoxacin
Gemifloxacin
117
how do fluroquinolones work?
bactericidal
inhibition of topoisomerase II (DNA gyrase) and IV → double-stranded DNA breaks → ⭣DNA replication and transcription
118
how do bacteria gain resistance against fluoroquinolones
topoisomerase II and IV mutations (chromosome encoded)
⭡fluoroquinole efflux (plasmid encoded)
** specially with staph aureus
119
what's the coverage of ciprofloxacin
gram positive ★
gram negative ★★★
additional coverage: pseudomonas
use: UTI, intra-abdominal infections, otitis externa, anthrax
120
which generation of fluroquinolones works great with respiratory infections
3rd and 4th gen = Levofloxacin, Moxifloxacin, Gemifloxacin
121
whats the coverage of levofloxacin
gram positive ★★
gram negative ★★
best fluoroquinole for strep pneumo coverage
additional coverage: mycobacterium tuberculosis, pseudomonas, atypicals
use: community acquired and hospital acquired pneumonia, UTI
122
best fluoroquinole for strep pneumo coverage
levofloxacin
123
coverage of moxifloxacin
gram positive ★★
gram negative ★★
additional coverage: mycobacterium tuberculosis, atypicals, **anaerobes**
use: CAP
124
adverse effects of fluroquinolones
**QT prolongation**
arthrophaty
**tendon and cartilage damage**
superinfections
GI discomfort
pseudomembranous colitis
nephrotoxicity
teratogenicity
**avoid in the elderly, marfans, ehler danlos
125
in which cases should you avoid the use of fluroquinolones
- avoid in the elderly, marfans, ehler danlos
- avoid with divalent cation preparations (iron, antiacids)
- they unite in the GI tract and avoid absortion
- avoid in pregnancy, breastfeeding, and children <18 yo
126
which fluoroquinolon is a CYP41A inhibitor
Ciprofloxaxin
127
how does metronidazole work
bactericidal
selective uptake from anaerobes → reduced electron transport chain → free radical production → DNA strand breaks → ⭣DNA replication and transcription
128
what does metronidazole primarily cover
anaerobes
129
what's the use of metronidazole
pseudomembranous colitis, intra-abdominal infection, giardiasis, trichomoniasis, bacterial vaginosis, peptic ulcer disease (h. pylori)
130
in which cases do you use metronidazole in the treatment of h.pylori
when the patient has a true allergy to penicillin
131
what are the adverse effects of metronidazole
metallic taste, peripheral neuropathy
132
what drugs target Nucleic Acid Synthesis or Folic Acid Pathways
fluroquinolones
metronidazole
sulfonamides
trimethoprim
133
which are the most commonly used sulfonamides
sulfamethoxazole (SMX), sulfadiazine, sulfisoxazole
134
how are sulfonamides used
they can be delivered orally or injected, but they need to be activated in the liver
135
what's the mechanism of action of sulfonamides
bacteriostatic if used alone, bactericidal if used with diaminopyrimidine
inhibition of dihydropterote synthase → ⭣bacterial DNA synthesis
136
what does the TPM-SMX therapy cover
gram positive ★★
gram negative ★★
= broad spectrum
additional coverage: pneumocystis, toxoplasma, nocardia, listeria, isospora, MRSA
use: pneumocystis pnenumonia (prophylaxis and treatment), toxoplasmosis (prophylaxis), nocardiosis, listeriosis, skin infections, AOM, UTI
137
what are the adverse effects of sulfonamides
nephrotoxicity, pancytopenia, hemolytic anemia (G6PD deficiency), photosensitivity, hypersensivity reactions (sulfa), SJS
138
which CYP is inhibited by sulfonamides and what drugs are affected by it
CYP2C9 inhibitor → warfarin, anti epileptics, anti inflamatories
139
contraindications for TPM-SMX =
pregnancy, early infancy
140
how does trimethoprim work
bacteriostatic if used alone, bactericidal if used with sulfonamide = TMP/SMX
inhibition of dihydrofolate reductase → ⭣bacterial DNA synthesis
141
adverse effects of trimethoprim
megaloblastic anemia, hyperkalemia, teratogenic
142
drugs for tuberculosis and leprosy
rifamycins
isoniazid
pyrazinamide
ethambutol
dapsone
143
how does isoniazid work?
bactericidal
⭣mycolic acid synthesis → ⭣cell wall synthesis
prodrug → bacterial katG gene required to activate
144
how does bacteria gain resistance against isoniazid
katG gene mutations (⭣bacterial catalase-peroxidase activity)
145
adverse effects of isoniazid
**hepatotoxicity**
drug-induced lupus
seizures
**neurotoxicity (vitamin b6 deficiency)**
-> normally you give this drug with pyridoxine (B6), because this drug tends to give you a b6 deficiency
146
does isoniazid inhibit any CYPs?
CYP1A2, CYP2A6, CYP2C19, and CYP3A4 inhibitor
147
which drugs are considered rifamycins
rifampin, rifabutin, rifapentine, rifaximin
148
how do rifamycins work?
bactericidal
inhibition of DNA-dependent RNA polymerase → ⭣bacterial mRNA → ⭣protein synthesis
149
how do bacteria gain resistance agains rifamycins
mutation in genes encoding DNA-dependent RNA polymerase
150
whats the use of rifamycins
tuberculosis (RIPE)
leprosy
meningococcal prophylaxis
hepatic encephalopathy (Rifaximin)
it can be used for staph infections (serious cases)
- tx for leprosy by tubercoloid mycobacteria = rifampin + dapsone
- rifampin works with latent tb
- meningococcal prophylaxis → rifampin, ciprofloxacin, ceftraxone
151
side effects of rifamycins
orange-red discoloration to body fluids, hepatotoxicity, pancytopenia
152
does rifamycin inhibit any CYPs
NO
CYP3A4 and CYP2C9 INDUCER (rifampin > rifabutin)
153
which rifamycin induces more the CYPs
rifampin
154
which rifamycin induces less the CYPs
rifabutin
155
can you use rifamycins alone?
NEVER USE IT ALONE → rapid resistance
156
how does pyrazinamide work?
bactericidal
decreases the synthesis of mycolic acid
157
adverse effects of pyrazinamide?
hyperuricemia = px will probably develop gout (gota)
hepatotoxicity
158
how does dapsone work
bacteriostatic
competitive antagonist of **PABA** → **⭣bacterial DNA synthesis**
159
whats the use of dapsone
leprasy, pneumocystis pneumonia, toxoplasmosis, malaria, dermatitis herpetiformis
*to treat malaria (and toxoplasmosis) you combine dapsone + pyrimethamine = bactericidal
**dermatitis herpetiformis → 1st line treatment is dapsone
160
whats the first line of tx for dermatitis herpetiformis
dapsone
161
adverse effects of dapsone
methemoglobinemia, hemolytic anemia (G6PD deficiency), agranulocytosis, peripheral neurophaty, DRESS syndrome
162
whats the empiric antibiotic coverage for community acquired pneumonia
ceftriaxone + azithromizin OR levofloxacin
163
whats the empiric antibiotic coverage for healthcare acquired pneumonia
vancomycin + cefepime OR cetfadizime OR piperacillin (+ tazobactam)
164
whats the empiric antibiotic treatment for sinusitis
amoxicillin +/- clavulanate
165
whats the empiric antibiotic coverage for pharyngitis
penicillin V
166
what bacteria are you trying to cover when treating empirically for community acquired pneumonia
staph neumo and mycoplasma pneumo
167
what bacteria are you trying to cover when treating empirically for healthcare acquired pneumonia
pseudomonas, MRSA and legionella
168
what do you use as empiric treatment for sinusitis when te patient has a true allergy to PNC
doxycycline
169
what are you trying to treat when you treat for pharyngitis
strep
170
whats the empiric general treatment for meningitis
ceftriaxone and vancomycin
171
whats the empiric neonatal treatment for meningitis
cefotaxime, ampicillin and gentamicin
172
whats the empiric elderly treatment of meningitis
ceftriaxone, vancomycin and ampicillin
173
why do you add ampicillin in some cases when you treat for meningitis
you add it to cover in the elderly and neonates tu also cover for listeria
174
whats the treatment for acute cystitis
TMP-SMX OR Nitrofurantoin OR Fosfomycin
175
whats the treatment of pyelonephritis
Ciprofloxaxin OR Ceftriaxone
176
what are the broad spectrum antibiotics for GI infections
Carbapenem OR piperacillin-tazobactam
177
whats the dual therapy for GI infections
Metronidazole + Ceftriaxone OR Ciprofloxacin
178
whats the empiric treatment treatment when your patient has diarrhea and you suspect C.dificille
Fidaxomicin OR Vancomycin (oral)
179
whats the empiric surgical profilaxis
Cefazolin
180
whats the empiric treatment for mild celullitis
Cephalexin, nafcillin
** you want to cover staph
181
whats the empiric treatment for moderate cases of celullitis
TMP-SMX, penicillin, Ceftriaxone, Clindamycin, Doxycycline (various alternatives)
182
whats the special talent of Clindamycin when you treat celulitis
it helps with toxic shock syndrome
183
whats the empiric treatment for severe cases of celulitis
Vancomycin
+/- Piperacillin-tazobactam OR Meropanem
add the later ones if you suspect pseudonomas
184
what's the empiric treatment for osteomyelitis when you want to cover for MRSA
Vancomycin
185
when you have septic arthritis and you suspect a gonococcal infection the empiric treatment is...
Ceftriaxone
186
if your patient has osteomyelitis but he also has many comorbilities the empiric treatment should be
Vancomycin + Piperacillin-tazobactam OR Ceftriaxone (vertebral)
**you'll want to cover for pseudomonas and anaerobes
187
for an hematogenous infections because of a catheter infection, what should be the empiric treatment
Vancomycin +/- Piperacillin-tazobactam OR Meropenem
188
whats the treatment for mycobacterium avium complex (MAC)
ethambutol + macrolide
189
whats a good use for rifaximin
good for ammonia producing bacteria in the GI tract
it helps with hepatic encephalopaty
