Microbiology Flashcards
(35 cards)
Ampicillin/amoxicillin
HELPSS kill Enterococci (and normal pens)
H. Flu, E. Coli, Listeria, Proteus, Salmonella, Shigella, Enterococci
Hypersensitivity, Rash, Pseudomembranous colitis
Penicillinase resistant penicillins
Oxacillin, Nafcillin, dicloxacillin
Narrow spectrum, use for staph
bulky R-group
Hypersensitivity, Interstitial nephritis
First gen Cephalospirins
Cefazolin, Cefalexin
PEcK- Proteus, E. Coli, Klebsiella, GPC
Cafazolin before surg for staph
Cephalospirins toxicities and what they don’t cover
Dont Cover LAME
Listeria, Atypicals (Chlamidia, mycoplasma), MRSA, Enterococci
Except, ceftaroline covers MRSA
Hypersensitivity, Vitamin K deficiency, increases nephrotoxicity of aminoglycosides
Aztreonam
monobactam, B-lactamase resistant Only covers aerobic GNRs Binds PBP3 nontoxic "pen allergic patient w/ renal insufficiency and can't tolerate aminoglycosides"
Carbapenems
Imipenem, meropenem, ertapenem, doripenem
Imipenem needs cilistatin to block renal dehydropeptidase I.
meropenem has fewer seizures and stable to dehydropeptidase I
Wide spectrum but toxicity limits use
GI, Rash, CNS toxicity (seizures) at high plasma levels
Vancomycin
Binds D-ala-D-ala
Only GPC (and oral for C. Diff)
Nephrotoxic, ototoxic, thromboembolic, red man syndrome if too fast
bacteria block by AA modification of peptidoglycan to D-ala-D-lac
Aminoglycosides
GNATS- Gentamicin, Neomycin, Amikacin, Tobramycin, Streptomycin
Inhibit formation of initiation complex and causes mRNA misreading
Binds 30s TIGHTLY, bacteriocidal
Requires O2 for uptake
Severe GNR infections, synergy w/ B-lactams
Neomycin for bowel surgery
TONN- Teratogenic, Ototoxic (esp w loop diuretics), nephrotoxic (esp w/ cephalosporins), Neuromuscular blockade
Bacterial transferase enzymes inactivate drug by acetylation, phosphorylation, or adenylation
Tetracyclines
Tetracycline, doxycicline, minocycline
Bind 30s, prevent aminoacyl-tRNA attachment
limited CNS penetration, divalent cations block absorption in gut (milk, antacids, iron)
doxycicline pooped, okay for renal failure pts
Boriella Burgdorferi, Mycoplasma pneumonia, Rickettsia and chlamydia (accumulates intracellularly)
Discoloration of teeth, blocks bone growth, photosensitivity. No in pregnancy
Bacteria block by plasmid encoded transport pumps
Macrolides
Azythromycin, erythromycin, clarithromycin
Binds 23s of 50s and blocks translocation
atypical pneumonia, chlamydia, GPC
MACROTA- Motility (GI), Arrhythmia (QT long), Cholestatic Hepatitis, Rash, eOsinophilia, Theophylline and Anticoagulant increases in blood
E and C- inhibit p450. A does not.
Bacteria block by methylating 23S rRNA binding site
Chloramphenicol
Blocks peptidyltransferase at 50S subunit
Meningitis (H. Flu, N. Menin, S. Pneumo) and RMSF
Toxic but cheap so used in developing CNTRYs
Anemia (dose dependent), Aplastic anemia (dose independent), Grey Baby Syndrome (don’t have UDP-glucuronyl transferase)
Bacteria inactivate w/ plasmid encoded acetyltransferase
Clindamycin
Blocks translocation at 50s
Anaerobic above diaphragm (oral, lung abcess)
Causes C. Diff
Sulfonamides
Sulfadiazine, sulfisoxazole, sulfadiazine
Para-aminobenzoic acid antimetabilites inhibit dihydropteroate synthase (folate synthesis)
GP, GN, Nocardia, Chlamydia
Hypersensitivity, Hemolysis in G6PD deficient, Tubulointerstitial nephritis, photosensitivity, Kernicterus in infants, displace other drugs from albumin
Bacteria alter dihydropteroate synthase, PABA synthesis or block uptake
Trimethoprim
Inhibits bacterial DHFR
Combine w/ sulfonamides
UTIs, Shigella, Salmonella, PCP and Toxo prophylaxis
Can cause megaloblastic anemia, leukopenia, glanulocytopenia
Fluoroquinolones
-oxacin (fluoroq’s) and nalidixic acid (quinolone)
Inhibit DNA gyrase (topo II). Bacteriocidal
No NOT take w/ antacids
GNR of GI/GU, Neisseria
Can cause GI upset, superinfections, rashes, headache, Tendonitis and Tendon rupture, don’t give to kids/preg/old because cartilage damage
old and prednisone AND FQ- tendon rupture
Bacteria get chromosome encoded mutation in DNA gyrase, plasmid mediated resistance and efflux pumps
Metronidazole
Forms free radical toxic metabolites in bacteria that damage DNA
Bacteriocidal, antiprotozoal
GET GAP on the metro
Giardia, Entamoeba, Trichomonas, Gardnerella, Anaerobes, Pylori
Disulfram-like rxn w/ alchohol, metallic taste
Anaerobic infections BELOW diaphragm
Isoniazid
Decreases synthesis of mycolic acid
Bacterial catalase-peroxidate (KatG) needs to convert INH to active metabolite
TB- only solo agent used
Check fast v. slow acetylators
Neurotoxicity (give B6), hepatotoxic, lupus
Rifamycins
Rifampin, Rifabutin Inhibits DNA dependent RNA Polymerase Delays dapsone resistance in Leprosy prophylaxis for meningicoccus prophylaxis in child contacts of H. Flu 4 R's RNA polymerase inhib Ramps up p450 Red/orange body fluids Rapid resistance if alone RifAMPin ramps up p450 (use rifabutin in HIV)
Pyrazinamide
Acidify phagolysosomes via conversion to pyrazinoic acid (TB phagocytized by macrophages)
hyperuricemia, hepatotoxicity
Ethambutol
Blocks arabinosyltransferase (decrease cell wall carbohydrate polymerization) optic neuropathy (R-G color blind) (reversible but check vision periodically)
Amphototericin B
Binds ergosterol (fungi), forms pores
use in serious systemic mycoses, intrathecally for fungal meningitis
fever/chills, nephrotoxic (give Mg and K and hydrate), arrhythmias, anemia.
Lyposomal amphototericin less toxic and potent
Nystatin
Pores like amphototericin
Really toxic, not absorbed, topical and swish/swallow for candida
Azoles
Inhibits fungal ergosterol synthesis by inhibiting p450 that converts lanosterol to ergosterol
Use for local and less serious
fluconazole- supress cryptococcal men in HIV
Itraconazole for blast, cocc, histo
clotrim and micon for topical
Ketoconazole inhibits testoterone synthesis
p450 inhibitor
Flucytosine
Inhibits DNA/RNA synthesis (cytosine deaminase converts to 5-FU)
systemic infection w/ Amphototericin B
Causes bone marrow supression
