Infectious Diseases and Immunizations Flashcards
Common pathogens for select sites: CNS/meningitis, mouth, upper and lower respiratory, endocarditis, SST, bones, and urinary tract
CNS/meningitis: Strep pneumo, Neisseria meningitidis, H. flu, Group B strep, E. coli (younger), Listeria (older)
Mouth: peptostreptococcus, Prevotella, strep groups, anaerobic Gram-negative rods
Upper respiratory: strep pyogenes, strep pneumo, H. flu, Moraxella catarrhalis
Lower respiratory: Community: Strep pneumo, H. flu, enteric Gram-negative, Legionella, Mycoplasma, Chlamydophila.
Hospital: Staph, pseudomonas, acinetobacter, strep pneumo, enteric Gram-negative rods (ESBL)
Endocarditis: Staph, aureus and epidermidis, strep, and enterococci
Abdominal: Enteric Gram-negative rods, enterococci, sttrep, Bacteroides
SST: Staph, strep, Pasteurella multocida
Bones: Staph and strep, Neisseria gonorrhoeae
Urinary tract: E. coli, Proteus, Klebsiella, staph saprophyticus, enterococci
Pathogen Gram staining and shapes
Atypicals: Chlamydia, Legionella, Mycoplasma pneumoniae, Mycobacterium tuberculosis
Gram-positive: Purple
Anaerobes; peptostreptococcus, Propionibacterium acnes, C. diff, Clostridium
Rods; Listeria monocytogenes, Corynebacterium
Cocci in clusters; Staphylococcus
Cocci in pairs/chains; Streptococcus, Enterococcus
Gram-negative: Pink
Anaerobes; Bacteroides fragilis, Prevotella
Rods; Pseudomonas aeruginosa, H. flu, Providencia
Enteric rods; Proteus mirabilis, E. coli, Klebsiella, Serratia, Enterobacter, Citrobacter
Cocci; Neisseria
Coccobacilli; Acinetobacter baumannii, Bordetella pertussis, Moraxella catarrhalis
Spirochetes; H. pylori, Campylobacter, Treponema, Borrelia, Leptospira
Commonly resistant pathogens
Kill Each And Every Strong Pathogen
Klebsiella pneumoniae (ESBL, CRE)
Escherichia coli (ESBL, CRE)
Acinetobacter baumannii
Enterococcus faecalis/faecium (VRE)
Staphylococcus aureus (MRSA)
Pseudomonas aeruginosa
Pharmacokinetics/dynamics of antibiotics: hydrophilic vs lipophilic
Hydrophilic agents:
Small Vd (less tissue penetration), really eliminated, low intracellular concentration (less active against atypical), and poor bioavailability (not 1:1)
Beta-lactams, aminoglycosides, vancomycin, daptomycin, polymyxins
Lipophilic agents:
Larger Vd (more tissue penetration), hepatically cleared, high intracellular concentration (active against atypical), good bioavailability (IV:PO is 1:1)
Quinolones, macrolides, rifampin, linezolid, tetracyclines
Classification of antibiotics and MOA
Cell wall inhibitors: bacteriocidal
Beta-lactams, monobactams, vancomycin, dalbavancin, telavancin, oritavancin
Cell membrane inhibitors: bacteriocidal
Polymyxins, daptomycin, telavancin, oritavancin
DNA/RNA inhibitors: bacteriocidal
Quinolones, metronidazole, tinidazole, rifampin
Protein synthesis inhibitors: bacteriostatic
Aminoglycosides (only bacteriocidal), macrolides, tetracyclines, clindamycin, linezolid, tedizolid, quinupristin/dalfopristin
Folic acid synthesis inhibitors: bacteriostatic
Bactrim, dapsone
Penicillins
Generally Gram-positive, however not active against MRSA
BBW: Penicillin G benzathine should never be used IV due to cardiac arrest
SE: seizures with accumulation, GI upset, diarrhea, rash (SJS/TENS), allergic reaction, anaphylaxis, hemolytic anemia (positive Coomb’s test)
CI: Type 1 reaction, CrCl <30
Monitor renal function
Natural penicillins: Gram-positive strep, enterococci, and anaerobes, not staph, no Gram-negative
Penicillin VK PO, penicillin G aqueous IV, penicillin G benzathine (Bicillin L-A) IM
Antistaphylococcal: Gram-positive strep, preferred for MSSA, no renal adjustments
Dicloxacillin PO, Nafcillin IV/IM (vesicant; use hyaluronidase), oxacillin IV
Aminopenicillins: Gram-positive strep, enterococci, anaerobes, Gram-negative H. flu, Neisseria, Proteus, and E. coli
Aminopenicillins with beta-lactamase inhibitors: added activity to MSSA and Gram-negative anaerobes
Amoxicillin PO, amoxicillin/clavulanate (Augmentin) PO (14:1 ratio), Ampicillin PO (rarely used d/t bioavailability) IV/IM, ampicillin/sulbactam (Unasyn) IV (dilute in NS only)
Extended-spectrum: Gram-positive strep, MSSA, enterococci, anaerobes, Gram-negative HNPEK, CAPES, and Pseudomonas
Piperacillin/tazobactam (Zosyn) IV over 4 hours (has 65mg Na per 1g pip)
Interactions: Probenecid increases levels, penicillins increase methotrexate, and warfarin (except nafcillin and dicloxacillin, which reduces warfarin)
Cephalosporins
Generally not active against enterococcus or atypicals
Warnings: cross-reactive with penicillin allergies, cefotetan can increase the risk of bleeding and disulfiram reaction with alcohol d/t NMTT side chain
SE: seizures with accumulation, GI upset, diarrhea, rash (SJS/TEN), allergic reaction, anaphylaxis, hemolytic anemia (positive Coomb’s test)
CI: hyperbilirubinemia neonates d/t kernicterus if neonates are <28d, do not use with Ca-containing products
Monitor renal function
First generation: Gram-positive cocci, Gram-negative PEK; Proteus, E.coli, Klebsiella
Cephalexin (Keflex) PO (250-500mg q6-12H), cefazolin IV/IM, cefadroxil PO
Second generation: MSSA, S. pneumo, H. flu, Neisseria, Proteus, E. coli, and Klebsiella, cefotetan and cefoxitin adds Gram-negative anaerobes
Cefuroxime PO/IV/IM, cefotetan IV/IM, cefoxitin IV/IM, cefaclor PO, cefprozil PO
Third generation: Resistant strep, MSSA, Gram-positive anaerobes, and resistant HNPEK, ceftazidime covers Pseudomonas, but not Gram-positives
Cefdinir PO, ceftriaxone IV/IM (no renal adjustments), cefotaxime IV/IM, cefixime PO/chewable, cefpodoxime PO, ceftazidime IV/IM
Fourth generation: similar to ceftriaxone, add HNPEK, CAPES, and Pseudomonas
Cefepime IV/IM
Fifth generation: similar to ceftriaxone, add broad Gram-positive and MRSA
Ceftaroline fosamil (Teflaro) IV
Combinations: adds MDR Gram-negative rods
Ceftazidime/avibactam (Avycaz) IV (active against CRE), ceftolozane/tazobactam (Zerbaxa) IV
Sixth/other: Uses iron transport system. Active against E. coli, Klebsiella, Proteus, and Pseudomonas in complicated urinary infection
Cefiderocol (Fetroja) IV
Interactions: Ceftriaxone produces precipitates with Ca, acid reducers decrease cefuroxime, cefpodoxime, and cefdinir bioavailability
Carbapenems
Very broad spectrum reserved for MDR Gram-negative infections, however active against Gram-positive, anaerobic, and ESBL. No activity against atypical, MRSA, VRE, C. diff, and Stenotrophomonas
Warnings: do not use in PCN allergies, seizure risk
CI: Anaphylaxis to PCN
SE: Diarrhea
Monitor renal function
Doripenem IV
Imipenem/cilastin IV, imipenem/cilastin/relebactam (Recarbrio) IV (cilastin prevents degradation)
Meropenem IV, meropenem/vaborbactam (Vabomere)
Ertapenem (Invanz) IV/IM (Lack of Pseudomonas, acinetobacter, and enterococcus, stable in NS only)
Interactions: Decreases valproate, can decrease seizure threshold
Monobactams
Generally covers Gram-negative including Pseudomonas and CAPES, no activity against anaerobes or Gram-positives. Used in PCN allergy.
SE: similar to PCN
Aztreonam (Azactam)
Aminoglycosides
Active against Gram-negative including Pseudomonas, not used as monotherapy, used with synergy for Gram-positive
BBW: nephrotoxicity, ototoxicity, neuromuscular blockade, teratogenic
Warnings: caution in renal impairment, esp. elderly, and nephrotoxic drugs (amphotericin B, cisplatin, polymyxins, cyclosporine, loops, NSAID, contrast, tacrolimus, vancomycin)
SE: nephrotoxicity (acute tubular necrosis), ototoxicity (high pitch and balance)
Monitor renal function and drug levels
Gentamicin IV/IM/opth/top, tobramycin IV/IM/opth/inh, amikacin IV/IM, streptomycin IM, plazomicin IV (reserved for MDR Gram-negative UTI’s)
Dosing: traditional based on peak and trough, extended interval uses the nomogram with random level. Gentamicin and tobramycin traditional dosing: 1-2.5mg/kg/dose, extended dosing: 4-7mg/kg/dose
Peak and trough levels are based on drug and indication: gentamicin for synergy is 3-4mcg/mL pk, and <1 tr. Gentamicin in Gram-negative and tobramycin should be 5-10 pk and <2 tr. Amikacin is 20-30 pk and <5 tr.
Renal clearance determines interval: CrCl >60 is q8H
Underweight uses total body weight, overweight uses adjusted, and regular uses IDB.
Quinolones/Fluroquinolones
Concentration-dep activity against both Gram and atypicals, and is last line for sinusitis, bronchitis, and uncomplicated UTI
BBW: tendon inflammation or rupture, peripheral neuropathy, seizures
Warnings: QT prolongation (highest is moxi), glycemic changes, psychiatric changes, avoid in children and pregnancy, photosensitivity
CI: cipro with tizanidine
SE: the usual
Ciprofloxacin (Cipro) PO/IV; with dexamethasone ear drops (Ciprodex); oral suspension cannot go into tubing
Levofloxacin PO/IV, Moxifloxacin IV/PO (no renal adjustments, not for UTI), delafloxacin PO/IV, gatifloxacin opth, ofloxacin (Ocuflox) PO/opth
Respiratory coverage of S. penumo; levo/moxi
Pseudomonas; levo/cipro
Anaerobic; moxi
MRSA; dela
Interactions: polyvalent cations d/t chelation, phosphate binders (separate by 2 hours, or 6 with Sevelamer), QT prolonging drugs (azoles, antipsychotics, methadone, macrolides), probenecid and NSAID’s increase levels, quinolones increase warfarin, sulfonylurea, and cipro d/t 1A2 increases caffeine, theophylline, and tizanidine
Macrolides
Covers atypicals (Legionella, chlamydia, Mycoplasma, Mycobacterium, H. flu), esp in community respiratory illness, and chlamydia. High resistance in S. pneumo, H. flu, chlamydia, and Moraxella
Warnings: QT prolongation (erythromycin is highest), hepatotoxicity, clarithromycin in CAD
CI: lovastatin and simvastatin in clarithromycin or erythromycin
SE: GI upset
Azithromycin (Zithromax, Z-pak) PO/IV (better G-), clarithromycin PO (better G+), erythromycin (E.E.S., Ery-Tab, Erythrocin) PO/IV
Interactions: E and C are substrates of 3A4, used caution in Eliquis, colchicine, Xarelto, theophylline, and warfarin. Azith has less SE. All have caution in QT prolongation
Tetracyclines
Covers many Gram-positive including staph, strep, enterococci, and Propionibacterium, Gram-negative including H. flu, Moraxella, atypicals, and unique pathogens including Rickettsiae, anthrax, syphilis.
Warnings: limit use in children <8yo and pregnancy, photosensitivity, and minocycline can cause DILE (lupus)
For doxy an mino, IV:PO is 1:1
Doxycycline (Vibramycin) PO/IV(no renal adjustment, sit upright for 30min after admin), minocycline (Minocin, Solodyn) IV/PO, eravacycline IV (only for abdominal infections), omadacycline IM/PO, sarecycline PO (only for acne), tetracycline PO
Interactions: polyvalent cations, sucralfate, bismuth, bile acid resins, dairy, multivitamins, and lanthanum Fosrenal can decrease drug
Sulfonamides
Active against MSSA/MRSA, and broad Gram-negative (H. flu, Proteus, E. coli, Klebsiella, Enterobacter, Shigella, Salmonella, and stenotrophomonas), oppurtunistic infections (Nocardia, PJP, toxoplasmosis). No activity agaisnt Pseudomonas, eneterococci, atypicals, anaerobes, S. penumo, or strep.
Warnings: Skin reactions SJS/TEN/TTP, hemolytic anemia (positive Coomb’s test) caused by immune system or G6PD deficiency, teratogenic
CI: sulfa allergy, anemia, <2mos
SE: photosensitivity, hyperkalemia, crystalluria, false high SCr
Sulfamethoxazole/trimethoprim (Bactrim) ratio 5:1, dose based on TMP
SS: 400/80mg PJP ppx daily
DS: 800/160mg UTI BID or ppx daily
Severe infections: 10-20mg/kg/day
Interactions: 2C8 and 2C9 inhibition; increases warfarin and INR, enhances MTX, diminished by leucovorin, hyperkalemia esp with ACEI/ARB or renal impairment.
Glycopeptide
Only covers Gram-positive including MRSA, strep, enterococci, and C. diff (oral only)
Warnings: ototoxicity, nephrotoxicity, PO is not systemically absorbed, Red Man Syndrome if infused too fast (1g/hr)
Monitor renal function, drug levels, AUC/MIC ratio or trough; serious infection AUC is 400-600, trough 15-20mcg/mL
Vancomycin (Vancocin) IV 15-20mg/kg q8-12H (total body weight), or PO 125mg QID x 10 days
CrCl 20-50 extend interval QD
Generally first-line for MRSA, unless MIC >2
Interactions: nephrotoxicity and ototoxicity are compounded
Lipoglycopeptides
Concentration-dep against Gram-positive bacteria (similar to vanco)
BBW: teratogenic, nephrotoxicity (increased mortality)
Warnings: infusion reaction with rapid admin, falsely raise aPTT/PT/INR without increased bleeding risk (orit/tela), QT prolongation (tela), 3X ULN ALT (dalb)
CI: Oritavancin; do not use IV UFH for 5 days due to aPTT abnormalities
Telavancin IV (SSTI), oritavancin IV (one dose over 3 hours), dalbavancin IV (single dose over 30 min)
Interactions: Decompensated HF, QT prolongation
Cyclic lipopeptide
Concentration-dep activity against Gram-positive including MRSA, and VRE
Warnings: myopathy and rhabdo, falsely elevate PT/INR without bleding risk
SE: increased CPK
Monitor CPK weekly
Daptomycin (Cubicin, Cubicin RF) IV (not for PNA)
Cubicin is compatibe with NS and LR (no dextrose), Cubicin RF compatible with NS after dilution with sterile water
Interactions: additive risk with statins
Oxazolidinones
Binds to 50S bacterial ribosome (inhibits translation and synthesis)
Activity against Gram-positive including MRSA and VRE
Warnings: myelosuppression if >14d, optic neuropathy if >28d, serotonin syndrome, hypoglycemia
CI: do not use within 2 weeks of an MAOI
SE: thrombocytopenia
Monitor CBC weekly
Linezolid (Zyvox) IV/PO (1:1 ratio, no renal adjustments)
Tedizolid IV/PO (1:1 ratio, no renal adjustments)
Interactions: avoid tyramine and serotonergic drugs d/t MAOI MOA, can exacerbate hypoglycemic episodes
Streptogramin
Binds the 50S bacterial ribosome (inhibits synthesis)
Active against Gram-positive including MRSA, and VRE, but not E. faecalis
SE: arthralgias, myalgias, infusion reactions, hyperbilirubinemia
Quinupristin/dalfopristin IV
Dilute in D5W only, administer centrally only
Glycylcycline
Binds to 30S bacterial ribosome (inhibits synthesis)
Broad spectrum against including VRE and MRSA, G+/G-, atypicals and anaerobes. Not active against Pseudomonas, Proteus, Providencia
BBW: increased risk for death (use is limited)
Warnings: structurally similar to tetracyclines; avoid in children <8yo
Tigecycline (Tygacil) IV (not for blood infections, solution is yellow-orange color)
Polymyxins
Active against MDR Gram-negative including Enterobacter, E. coli, Klebsiella, Pseudomonas. Not active against Proteus. Generally in combo with others
Colistimethate/colistin IM/IV/inh (mix immediately prior to use
Warning: dose-dep nephrotoxicity, neurotoxicity
Prodrug; assess dose carefully
Polymyin B IV
BBW: dose-dep nephrotoxicity, neurotoxicity d/t neuromuscular blockade (resp. paralysis)
1mg=10,000units
Interactions: nephrotoxicity is additive
Chloramphenicol
Reversibly binds 50S of bacterial ribosomes (inhibits synthesis)
Very broad spectrum
Warning: gray syndrome (circulation issues, cyanosis, acidosis, myocardial depression, coma)
Chloramphenicol IV
Lincosamide
Reversibly binds 50S of bacterial ribosomes (inhibits synthesis)
Active against Gram-positive including MRSA and anaerobes. Does not cover Gram-negative, or Enterococci
BBW: C. diff colitis infection
SE: N/V/D
Clindamycin (Cleocin) IV/PO (no renal adjustments)
Clindamycin topical (Clocin-T, Clindagel)
Induction D-test for S. aureus to determine erythromycin cross-resistance
Antibiotic/Antifungal class
Causes loss of helical DNA structure and strand breakage (inhibits synthesis)
CI: pregnancy 1st trimester, alcohol d/t disulfiram
SE: metallic taste
Metronidazole (Flagyl) PO/IV/top/vag (IV:PO is 1:1)
Active against protozoans, anaerobes, and is used for bacterial vaginosis, trichomoniasis, giardiasis, amebiases, and C. diff
Interactions: alcohol, 2C9 inhibition (increased INR)
Tinidazole PO
Active against protozoan giardiasis, amebiasis, trichomoniasis, and bacterial vaginosis
Secnidazole PO (single dose)
Active for bacterial vaginosis, trichomoniasis
SE: vulvovaginal candidiasis
Pleuromutilin
Binds to 50S ribosome (inhibits synthesis)
Used for CAP
Lefamulin IV/PO
Warnings: QT prolongation
Fidaxomicin
Used for C. diff
Fidaxomicin (Dificid) PO
Warnings: only for GI, not systemically absorbed
