ID - Bacterial Infections / ABXs Flashcards
Gram Positive Cocci Organisms (clusters, pairs, chains)
Clusters: Staphylococcus ssp. (MRSA, MSSA)
-Coagulase (+): S. aureus
Pairs and Chains:
-Streptococcus spp. (Strep. pyogenes)
-Enterococcus spp.
-Diplococci: S. pneumoniae
Gram Positive Anaerobes Organisms
Peptostreptococcus
Actinomyces spp.
Clostridium spp.
Gram Positive Rod Organisms
Listeria monocytogenes
Gram Negative Cocci Organsisms
Neisseria spp.
Gram Negative Rods Organisms
Enterobacterials (colonize gut): Proteus mirabilis, Escherichia coli, Klebsiella spp., Serratia spp., Enterobacter cloacae, Citrobacter spp.
do NOT colonizer gut: Pseudomonas aeruginosa, Haemophilus influenzae, Providencia spp.
Gram Negative curved or spiral shaped rods Organisms
H. pylori
Campylobacter spp.
Treponema spp.
Borrelia spp.
Leptospira spp.
Gram negative Coccobacilli Organisms
Actineobacter baumannii
Bordetella pertussis
Moraxella catarrhalis
Gram negative Anaerobe Organisms
Bacterioides fragilis
Prevotella spp.
Atypical Organisms that do not gram-stain well (no cell wall)
Chylamydia spp.
Legionella spp.
Mycoplasma pneumoniae
Mycobacterium tuberculosis
Common Bacterial Pathogens for CNS/Meningitis
Streptococcus pneumoniae
Neisseria meningitidis
Haemophilus influenzae
Group B Streptococcus/E.coli (young pts)
Listeria (young/old pts)
Common Bacterial Pathogens for Upper Respiratory Tract Infection (URTIs)
Streptococcus pyogenes
Streptococcus pneumoniae
Haemophilus influenzae
Moraxella catarrhalis
Common Bacterial Pathogens for infections in mouth
Mouth flora: Peptostreptococcus
Anaerboic GNRs: Prevotella, others
Vridans group streptococci
Common Bacterial Pathogens for Lower respiratory tract infections (community acquired)
Streptococcus pneumoniae
Haemophilus influenzae
Atypicals: Legionella, Mycoplasma, Chlamydophila
Enteric GNR (alcohol use disorder)
Common Bacterial Pathogens for Intra-abdominal infections
Enteric GNR
Enterococci
Streptococci
Bacterioides spp.
Common Bacterial Pathogens for Heart/Endocarditis
Staphylococcus aureus, including MRSA
Staphylococcus epidermidis
Streptococci
Enterococci
Common Bacterial Pathogens for Lower respiratory tract infections (hospital acquired)
Staphyloccocus aureus, including MRSA
Pseudomonas aeruginosa
Actinetobacter baumannii
Enteric GNR (including ESBL+, MDR)
Streptococcus pneumoniae
Common Bacterial Pathogens for Skin/Soft tissue infections (SSTIs)
Staphylococcus aureus
Staphylococcus epidermidis
Steprotocccus pyogenes
Pasteurella multocida +/- aerobic/anaerobic GNR (DM)
Common Bacterial Pathogens for urinary tract infections (UTIs)
E. coli, Proteus, Klebsiella
Staphylococcus saprophyticus
Enterococci
Common Bacterial Pathogens for Bone/Joint Infections
Staphylococcus aureus
Staphylococcus epidermidis
Streptococci
Neisseria gonorrhoeae
GNR (in specific situations)
ABX Susceptibility Testing:
1. What is MIC?
- How is an ABX determined to be S, I, or R?
- Can MICs between ABXs be compared?
- What is an angiogram?
- Minimum Inhibitory Concentration - the minimum amount of ABX needed to prevent bacterial growth
- Compare the MIC to the “ susceptibility breakpoint” , the usual drug concentration that inhibits bacterial growth
-S = Susceptibile
-I = Intermediate: usually don’t use and try to use S
-R = Resistant: do NOT use - MIC is SPECIFIC to ABX and ORGANISM –> do NOT compare ABXs to one another based on MIC, but rather spectrum coverage needed
- Angiogram is a chart that takes culture data from patients at single institution usually over one year to monitor susceptiblity and resistance patterns
-Numbers are reported as percentage of times the drug covered the organism (100 ideal)
-Some may only be indicated with synergy (usage of another ABX together to cover organism)
Mechanisms of ABX Reistance:
-Intrinsic resistance
-Selection pressure
-Acquired resistance
Intrinsic: resistance: resistance is NATURAL to organisms (ex. E. coli is resistant to vancomycin because ABX is too large to penetrate cell wall)
Selection pressure: resistance when ABX kills susceptible bacteria, leaving behind more reistance strains to multiply (ex. Vancomycin eliminiates susceptible Enterococci, but some because vancomycin-resisatnt Enterococcus = VRE)
Acquired resistance: bacterial DNA containing resistant genes transferred between species and/or picked up from dead bacterial fragments in environment
Mechanisms of ABX Resistance: ABX degradation
Bacterial enzymes breakdown ABX
-Beta-lactamases can break down beta-lacatams (PCNs, cephalosporins) –> can use beta-lactamase inhibitors
-Extended-spectrum beta-lactamases (ESBLs): can breakdown ALL PCNs, most cephalosporins –> may need carbapenem or newer cephalosporins w/ beta-lactamse inhibitors
-Carbapenem-resistant Enterobacterales (CRE): MDR GNRs that produce carbapenemases –> often mutliple ABXs including polymyxins of ceftazidmine/avibactam (Avycaz)
Commonly resistant pathogens: “Kill Each And Every Strong Pathogen”
K: Klebsiella pneumoniae (ESBL, CRE)
E: Eschericha coli (ESBL, CRE)
A: Actineobacter baumannii
E: Enterococcus faecalis/faecium (VRE)
S: Staphylococcus aureus (MRSA)
P: Pseudomonas aeruginosa
ABX Pharmacokinetics: Which ABXs are hydrophilic and lipophliic, and how does this impact PK?
Hydrophilic: beta-lactams, amionglycosides, glycopeptides, daptomycin, polymyxins
-Small Vd, low intracellular concentrations (low tissue concentrations, more in blood)
-Renal elimination
-Increased clearance in sepsis
-Poor-moderate bioavailability
Lipophilic: quionoones, macrolides, rifampin, linezolid, tetracyclines, chloramphenicol
-Large Vd, achieves intracellular cocentrations (more in tissue, less in blood –> more activity w/ atypical aka intracellular pathogens)
-Hepatic metabolism
-Clearance minimally changed in sepsis
-Excellent bioavailability (typically 1:1 ratios PO to IV)
ABX Dosing Optimization: which ABXs are concentration dependent, AUC dependent, and time dependent?
-Goals with each category
-Dosing strategies with each category
Concentration Dependent (Cmax: MIC): aminoglycosides, quinolones, daptomycin
-Goal: high peak to increase bactericial activity and low troughs to decrease toxicity
-Dosing strategies: larger dose with longer intervals (dosed less frequently)
AUC: MIC - vancomycin, macrolides, tetracyclines, polymxins
-Goal: exposure over time
-Dosing strategies: variable
Time > MIC (Time-dependent): beta-lactams (PCNs, cephalosporins, carbapenems)
-Goal: maintain drug level > MIC for most of dosing interval
-Dosing strategies: shorter dosing interval, extended or CIV -> just care about how long the drug levels are > MIC
ABX MOAs: which ones work on cell wall inhibition
-Beta-lactams (PCNs, cephalosporins, carbapenems) and monobactams (aztreonam): bind to PCN-binding proteins (PBPs) which prevent peptidoglycan synthesis
-Vancomycin: binds to D-alanine-D-alanine cell wall precursor to peptidoglycans
-Dalbavancin, telavancin, ortivancin
ABX MOAs: which ones work on protein synthesis inhibition
clindamycin, linezolid, tedizolid
-30S Ribosome: aminoglycosides, tetracyclines
-50S Ribosome: macrolides
ABX MOAs: which ones work on cell membrane inhibition
polymyxins, daptomycin, televancin, ortivancin
-Daptomycin: binds to cell wall components causing rapid depolarization, inhibiting intraceullar replication processes including protein synthesis
ABX MOAs: which ones work on DNA/RNA inhibition
quinolones, metronidazole, tinidazole, rifampin
-Quinolones: toposiomerase IV and DNA gyrase (toposomerase II), promoting breakage of ds DNA
ABX MOAs: which ones work on folic acid synthesis inhibition
sulfonamides, trimethoprim, dapsone
-Sulfamethoxazone (SMX): inhibits dihydrofolic acid formation, inhibiting folic acid synthesis
-Trimethoprim (TMP): inhbitts dihydrofolic acid reduction to tetrahydrofolate, inhibitng folic acid pathway
Penicillins (PCNs): Bacterial Coverage
-Natural PCNs
-Antistaphylococcal
-Aminopenicillins
-Aminopenicillins + beta-lactamase inhibitor
-Extended spectrum + beta-lactamase inhiibitor
*What are class coverage trends?
Natural PCNs (penicillin G/V): streptococci, enterococci, and GP anaerobes in mouth flora (peptostreptococcus)
Antistaphylococcal (nafcillin, oxacillin, dicloxacillin): MSSA and streptococci only
Aminopenicillins (amoxicillin, ampicillin): natural PCN coverage + GN coverage (HNPEK)
Aminopenicillin + Beta-lactamase inhibitor (amoxicillin/clavulanate, ampicillin/sulbactam): MSSA, more resistant strains of HNPEK, GN anaerobes (B. fragilis)
Extended spectrum + Beta-lactamse inhibitor (piperacillin/tazobactam): aminopencillin/beta-lacatamase coverage + CAPEs and Pseudomonas coverage
Class Trends:
-Do NOT cover MRSA, atypical pathogens (NO cell wall)
-ALL cover enterococcus except anti-staph PCNs
*HNPEK: Haemophilus, Neisseria, Proteus, E.coli, Klebsiella
*CAPES: Citrobacter, Actinetobacter, Providencia, Enterobacter, Serratia
Brands and ROA for: Natural PCNs
-PO: PCN V Potassium (Pen VK)
-IV: PCN G Aqueous
-IM: PCN G Benzathine (Bicillin L-A) –> NEVER give IV (cardio-respiratory arrest and death)
ROA for: Antistaphylococcal PCNs
-PO: dicloxacillin
-IV: nafacillin. oxacillin
Brands and ROA for: Aminopenicillins
-PO: amoxicillin (Moxatag)
-IV: ampicillin (does come in PO, but RARELY used since poor bioavailability)
Brands and ROA for: Aminopenicillin/beta-lactamase inhibitors
-PO: amoxicillin/clavulanate (Augmentin)
-IV: ampicillin/sulbactam (Unasyn)
Brands and ROA for: Extended spectrum/beta lactamase inhibitors
-IV: piperacillin/tazobactam (Zosyn) - prolonged or extended infusions
Typical usages of the following PCNs:
-PCN VK
-Amoxicillin
-Augmentin
-Penicillin G Benzathine (Bicillin L-A)
-Zosyn
PCN VK: strep throat, mild skin infections
Amoxicillin: acute otitis media, infective endocarditis prophylaxis, H. pylori
Augmentin (amoxicillin/clavulanate): acute otitis media
PCN G Benzathine (Bicillin L-A): syphilus –> NEVER use IV (cardio-respiratory arrest and death)
Zosyn (piperacilllin/tazobactam): Pseudomonas –> extended-infusion common
PCN Dosing:
-Amoxicillin and amoxicillin/clavulanate dosing in pediatrics
-Amoxicillin dosing in infective endocarditis prophylaxis prior to dental procedures
-Penicillin G Benzathine for syphilus
-What PCN group does NOT need to renally dose adjusted?
-Which PCN should NOT be used in CrCl <30mL/min?
**KNOW amoxicillin in pediatrics dosing
Pediatrics:
-Amoxicillin component: 90mg/kg/day (acute otitis media: divide into BID)
-Clavulanate: use LOWEST dose (diarrhea)
Infective endocarditis prophylaxis prior to dental procedure: 2 grams PO x1 30-60 minutes before procedure
Benzathine G Benzathine: 2.4 million units IM x1 for early intervention or Qweek for 3 weeks (NEVER IV: lipid emulsion that can cause death)
NO renal dose adjustments: anti-staphy PCNs (nafacillin, oxacillin, dicloxacillin)
do NOT use in CrCl <30mL/min: Augmentin XR or 875mg strength
PCNs:
1. What are the major reasons to NOT select a PCN besides organism?
- What are side effects of PCNs?
- Which PCN is a vesicant preferred to be given through a cental line, and what should be done if extravasation occurs?
1.
-Beta-lactam allergy (except for syphilus during pregnancy or in pts with poor compliance/follow up –> densenitize and use treat w/ PCN G Benzathine)
-Try to avoid in hx of seizures (especially if decreased renal function)
- seizures (with accumulation), GI upset, diarrhea, rash (including SJS/TENs), hemolytic anemia (positive Coombs test), renal failure, increased LFTs
- Nafcillin - if extravasation, cold packs and hyaluronidase injections
PCNs:
1. What IV PCN should be preferrably diluted in NS?
- What are CIs specific to Augmentin and Unasyn?
- DDIs of PCNs
- Ampicillin including ampicillin/sulbactam
- Hx of cholestatic jaundice or hepatic dysfunction asosciated with previous usage
- -PROBENACID: increases level of beta-lactams
-PCNs can increase methotrexate concentrations
-Warfarin: PCNs enhance effects except nafcillin and dicloxacillin inhib
Cephalosporins coverage:
-1st gen (1GC)
-2nd gen (2GC)
-3rd gen (3GC)
-4th gen (4GC)
-5th gen (5GC)
-Cefiderocol
*What are class trends?
1GC (cefazolin, cephalexin): staphylococci, streptococci, PEK, mouth anaerobes (Peptostreptococcus) –> very similar to aminopenicillins
2GC (cefuroxime, cefotetan, cefoxitin): better GN activity (HNPEK)
-Cefoxitin, cefotetan: have anaerobic coverage (B. fragilis)
3GC:
-Group 1 (ceftriaxone, cefdinir): less staphylococci coverage, but better streptococci coverage
-Group 2 (ceftazidime, ceftazidime/avibactam): Pseudomonas
4GC (cefepime): broad; GP, HNPEK, CAPEs, Pseudomonas
5GC (ceftaroline): similar to ceftriaxone + MRSA coverage
Cefiderocol: PEK, Enterobacter, Pseudomonas
Class trends:
-NOT active against Enterococcus spp. or atypical organisms (NO cell wall)
-GN coverage increases typically with each generation
Cephalosporins Brands/ROAs:
-Cefazolin
-Cephalexin
-Cefuroxime
-Ceftriaxone
-Cefdinir
-Cefepime
-Ceftaroline
-Cefixime
-Ceftazifime
PO:
-Cephalexin (Keflex)
-Cefdinir (Omnicef - now D/C brand)
-Cefixime (3GC) - chewable tablets
IV:
-Cefazolin (Ancef)
-Ceftazidime (Tazicef), ceftazidime/avibactam (Avycaz)
-Cefepime (Maxipime)
-Ceftaroline (Teflaro)
IV, IM: ceftriaxone (Rocephin)
PO, IV, and IM: cefuroxime (Ceftin)
Cephalosporins: Typical Indications
-1GC
-2GC
-3GC
-4GC
-5GC
1GC:
-Outpatient: cephalexin –> strep throat, MSSA skin infections
-Inpatient: cefazolin –> surgical prophylaxis
2GC:
-Outpatient: cefuroxime –> acute otitis media, CAP, sinus infections
-Inpatient: cefotexan, cefoxitin –> surgical prophylaxis (GI procedures due to anaerobe coverage)
3GC:
-Outpatient: cefdinir –> CAP, sinus infections
-Inpatient: ceftraixone, cefotaxime –> CAP, meningitis, SBP, pylonephritis
Pseudomonas: ceftazidime, cefepime
MRSA: ceftaroline
Cephalosporins:
1. When would you try to avoid using cephalosporins?
- Side effects
- Which cephalosporin can cause disulfram-like reactions?
- Monitoring
- Penicillin allergy due to potential cross-reactivity (exceptions: mild PCN allergy, acute otitis media in pediatric pts since NOT many other options)
2.
-PCN symptoms: seizures (with accumulation, especially in renal dysfunction), GI upset, diarrhea, rash (including SJS/TENs), hemolytic anemia (positive Coombs test), increased LFTs,
-Others: acute interstitial nephritis, myleosuppression (prolonged use), drug fever
- Cefotetan
- Renal function, s/sx of anaphylaxis, CBC, LFTs
Cephalosporins:
1. Which cephalosporin does NOT need to be renally dosed?
- Which cephalosporin can have some activity against carbapenem-resistant Enterobacterioles (CRE)?
- What are CIs to using ceftriaxone?
- DDIs
- Ceftriaxone
- Ceftazidime/avibactam
- Neonates 0-28 days old
-Hyperbilirubinemic neonates (biliary sludging, neonates)
-Concurrent use w/ Ca-containing IV products in neonates (contributes to sludge as well) - Oral cephalosporins can have less bioavailability w/ decreased stomach acid
-Avoid H2RAs and PPIs
-Seperate from antacids
Carbapenems:
-Drugs/Brands
-ROA (which drug must be diluted in NS)
-Coverage
-Typical Indications
Drugs: meropenem (Merrem), meropenem/vaborbactam (Vabomere), impinem/cilastatin (Primaxin IV), imipenem/cilastatin/relebactam (Recarbrio), ertapenem (Invanz)
ROA: IV
-Ertapenem: IV and IM –> MUST be diluted in NS
Coverage: reserved for MDR GNRs (including ESBL)
-NO coverage of: atypical pathogens (NO cell wall), MRSA, VRE, C. diff, Stenotrophomonas
-ErtAPenem: NO activity against Enterococcus, Actineobacter, and Psuedomonas (“EAP”)
Indications:
-Polymicrobial infections (ex. severe diabetic foot infections)
-Empiric therapy w/ resistant organisms suspected
-ESBL-positive infections
-Resistant pseudomonas or Actineobacter infections (except ertapenem)
Carbapenems:
-AVEs
-Warnings/CIs
-Monitoring
-DDIs
AVEs: diarrhea, rash/severe skin rxns (DRESS), bone marrow suppression w/ prolonged use, increased LFTs
Warnings/CIs:
-Avoid with PCN allergy, especially in serious allergies
-CNS AVEs: confusion, SEIZURES (higher risk w/ imipenem/cilastatin, large doses, or impaired renal fxn)
-Caution in pts taking medications that lower seizure threshold (quinolones, clozapine, bupropion, tramadol)
Monitoring: renal function, allergic rxns, CBC, LFTs
DDIs: can decrease valproic acid levels, increasing seizure potential
Monobactam:
-Drugs/Brand
-ROA
-Coverage
-Typical indications
Drug: aztreonam (Azactam)
ROA: IV (Cayston for inhaled in cystic fibrosis)
Coverage: GN organisms including Pseudomonas and CAPES
-NO gram positive coverage
-NO anaerobe coverage
Typical indication: used when pencillin allergy present (cross-sensitivity VERY UNLIKELY with single ring structure)
Aminoglycosides:
-Drugs
-ROA
-Coverage
-Typical Indications
Drugs: gentamicin, tobramycin, amikacin, streptomycin, plazomicin
ROA: IV or IM (Tobramycin also has inhalation for cystic fibrois - Tobi, Bethkis, Kitabis Pak)
Coverage: GP and GN broad activity including Pseudomonas (mostly Tobramycin)
Typical Indications: USUALLY NOT MONOTHERAPY
-Genatamicin and Streptomycin: synergy in combo w/ beta-lactam or vancomycin when treating GP infections (staphylococci, enterococci)
-Empiric therapy for GN with other ABXs
Aminoglycosides:
-Dosing strategies
-Gentamicin and Tobramcyin: tradition and extended interval dosing
-What weight to use when calculating dose?
Dosing Strategies:
-Extended interval dosing to take advantage of concentration-dependent kinetics
-Larger doses less frequenctly to also give kidneys time to recover between doses)
-LOWER dosing for GP infections
Traditional Dosing:
-Usually 1.25-5mg/kg IV: use Q8H if CrCl >/= 60mL/min
-Trough: draw before or 30 minutes before 4th dose (goal: <2 mcg/mL)
-Peak: draw 30 minutes after end of infusion for 4th dose (goal: 5-10 mcg/mL)
-Higher TROUGH associated with MORE TOXICITY
Extended Interval Dosing:
-4-7 mg/kg IV Q24H (usually 7mg/kg)
-Draw random level and use nomogram to determine frequency
-Harford nanogram: determine time random level done and concentration to then see where it falls for time interval (if lands exactly on line go up to next dosing interval)
Selecting a weight when dosing:
-Underweight < IBW: use total body weight
-Normal weight: IBW or TBW (depends on institutional protocol)
-Obese: adjusted BW
Aminoglycosides:
-Warnings
-BBW
-Monitoring
Warnings:
-Caution in impaired renal function or older adults
-Caution with additive neurotoxic drugs: amphotericin B, cisplatin, polymyxins, cyclosporine, tacrolimus, loop diuretics, NSAIDs, radiocontrast dye, vancomycin
BBW: nephrotoxocity, ototoxicity (ataxia, vertigo, hearing loss), neuromuscular blockade and respiratory paralysis
-AVOID with other nephrotoxic drugs
-Fetal harm in pregnancy
Monitoring: drug levels, renal function, urine output, hearing tests
Quinolones:
-Drugs/Brands
-ROA
-Coverage
-Typical Indications
-Which quinolone do you NOT need to renally adjust?
Drugs: ciprofloxacin (Cipro), levofloxacin (Levaquin), Moxifloxacin (Avelox), delafloxacin, gatifloxacin, ofloxacin
ROA: PO or IV (Ocuflox - ofloxacin eye drops, Ciloxan - ciprofloxacin eye drops, Cetraxal - ciprofloxacin ear drops)
-IV to PO ratio: 1:1 (great bioavailability)
Coverage: GP and GN broad spectrum
-“Respiratory fluroquinolones”: levofloxacin, moxifloxacin, and gemifloxacin (enhanced coverage of S. pneumoniae and atypical pathogens)
-Pseudomonas: ciprofloxacin, levofloxacin (enhanced GN activity)
-Moxifloxacin: more GP activity and anaerobes–> cannot be used in UTIs (does NOT concentrate in urine)
-Delafloxacin: MRSA activity (others should be avoided due to MRSA resistance likelihood)
Indications: last-line infections if no alternatives
–Last line for acute bacterial sinusitis, acute exacerbation of chronic bronchitis, and uncomplicated UTI (BBW)
-Pseudomonas infections, UTI, intra-abdominal infections, traveler’s diarrhea
NO renal adjustment: moxifloxacin (think about how it does NOT concentration in urine)
Quinolones:
-AVEs
-Warnings
AVEs: N/D, HA, dizziness, serious skin rxns (SJS/TENs)
Warnings:
-QT prolongation (highest risk: moxifloxacin > levofloxacin > ciprofloxacin): avoid with known QT prolongation or those with additive risk (hypokalema, QT prolonging drugs)
-Hypoglycemia and hyperglycemia
-Psychiatric disturbances (agitation, disorientation, lack of attention, nervousness, memory impairment, delirium)
-Avoid in children and pregnancy/breastfeeding due to musculoskeletal toxicity risk (exception: anthrax exposure)
-Aortic aneurysm and dissection (increased risk w/ longer durations or hx of peripheral vascular disease, atherosclerosis, or prior aneurysms)
-Photosensitivity, hepatotoxicity, crystalluria (stay hydrated)
Quinolones:
-BBWs
-CIs
BBW:
-Tendon inflammation and/or ruptuure often in Achilles tendon within start up to several months after TX (increased risk w/ systemic steroids, organ transplant recipients, >60 yo) –> D/C immediately if symptoms occur
-Peripheral neuropathy: can last months to years after D/C and may become permenanent –> D/C immediately if symptoms occur
-CNS effects (seizures, tremor, restlessness, confusion, suicidal thoughts, etc.): caution in CNS disorders or drugs that cause seizures/lower threshold
-Avoid in myasthenia gravis (may exacerbate weakness)
CI: ciprofloxacin with concurrent administration of tizanidine
Quinolones: DDIs
- Antacids, polyvalent cations (Mg, Al, Ca, Phos, Iron, Zinc), multivitamins, sucralfate, bile acid resins: chelate and inhibit quinolone absorption
2.Phosphate binders (lanthanum, sevelamer): decrease concentration of PO quinolones (separate)
- Quinolones can increase effects of: warfarin, sulfonylureas, insulin, and other hypoglycemic drugs
- Caution w/ QT prolonging drugs or drugs that w/ CVD/decrease K/Mg: azole antifungals, antipsychotics, methadone, macrolides
- Ciprofloxacin: strong CYP1A2 inhibitor: can increase levels of caffeine, theophylline, tiazanidine
Macrolides:
-Drugs/Brands
-ROA
-Coverage
-Typical Indications
Drugs: azithromycin (Zithromax, Zpak), clarithromycin (Biaxin), erythromycin (E.E.S = erthromycin stearate, Erthyrocin)
ROA:
-Azithromycin: PO or IV
-Clarithromycin: PO
-Erythromycin: PO, IV, topical, opthalamic
Coverage:
-Great atypical coverage (Legionella, Chlamydia, Mycoplasma, Mycobacterium avium)
-Respiratory: H. influenzae, S. pneumonie, Moraxella (having increasing resistant rates)
Typical Indications:
-Community acquired upper and lower respiratory tract infections; strep throat
-Azithromycin: COPD exacerbations, chlamydia, gonorrhea, MAC prophylaxis
-Clarithromycin: H. pylori
-Erythromycin: increase gastric motility
Macrolides: azithromycin dosing
-Zpak dosing
-Tripak dosing
Z-pak: Two 250mg (500mg) on day then 250mg QD x4 days
Tripak: 1 azithromycin 500mg tablet QD x3 days
Macrolides:
-AVEs
-Warnings
-CIs
-DDIs
AVEs: GI UPSET (diarrhea, abdominal pain, cramping), taste perversion, ototoxicity (rare, reversible), severe skin infections (rare)
Warnings:
-QT prolongation: highest risk with erythromycin > azithromycin > azithromycin –> avoid in pts with known QT prolongation, elecrolyte abnormalties, and QT prolonging drugs
-Hepatotoxicity
-Exacerbation of myasthenias gravis
-Clarithromycin: caution in CAD (increased mortality been documented 1 year or after end of 2 week TX course)
Cis:
-Hx of cholestatic jaundice/hepatic dysfunction w/ prior use
-Clarithromycin and erythromycin: usage w/ lovastatin or simvastatin
-Clarithromycin: concurrent use with colchicine w/ renal or hepatic impairment
DDIs:
-Erthyromycin and Clarithromycin: major CYP3A4 inhibitors and substrates –> CYP3A4 subsrates some are CI (lovastatin and simvastatin) and some monitor (warfarin, apixiban/rivaroxaban, dabigatran, theophylline, colchicine)
-Azithromycin: MINOR CYP3A4 subsrate and weak inhibitor
-ALL macrolides: caution with QT prolonging drugs
Tetracyclines:
-Drugs/Brands
-ROA
-IV to PO ratio
-Which tetracyclines do NOT need to be renally adjusted?
Drugs: doxycycline (Vibramycin, Doryx), minocycline (Minocin, Solodyn), eravacycline, omadacycline, sarecycline, tetracycline
ROA: PO or IV
IV to PO ratio: 1:1 (doxycycline, minocycline)
NO renal adjustment: doxcycline, minocycline
Tetracyclines:
-Coverage
-Typical Indications
Coverage: GP and GN coverage
-GP: Staphylococci (including CA-MRSA), Streptococci, Enterococci (including VRE), Propionibacterium spp)
-GN: respiratory flora (H. influenaze, Moraxella, atypicals)
-Unique pathogens: RIckettsiae, Bacillus anthracis, Treponema pallidum, H. pylori (tetracycline)
-Doxycycline (often DOC): even broader with tickborne/rickettsial disease, STIs (chlamydia), and respiratory tract infecionts
Typical Indications:
-CA-MRSA skin infections, acne
-Doxycycline: tickborne infections, CAP, COPD exacerbations, sinusitis, VRE UTI, chlamydia, gonorrhea
-Tetracycline: H. pylori treatment
Tetracyclines:
-AVEs (which one should be taken upright for at least 30 minutes to avoid esophageal irritation?)
-Warnings
-Monitoring
-DDIs
AVEs: N/V/D, rash
-Doxycyline: take upright for at least 30 minutes (esophageal irritation)
Warnings:
-Children < 8 yo, pregnancy, breastfeeding: try to avoid (suppressed bone and skeletal development, premanent discolors teeth)
-Photosensitivity, tissue hyperpigmentation, severe skin infections (SJS/TEN/DRESS), exfolative dermatitis
-GI inflammation/ulceration
-Minocycline: drug-induced lupus erythematosus (DILE)
Monitoring: LFTs, renal fxn, CBC
DDIs: antacids, polyvalent cations, sucralfate, bismuth subsalicylate, and bile acid resins can chelate and inhibit absorption of tetracyclines (ideally avoid, but if not seperate –> seperate dairy products 1 hour before or 2 hours after)
Sulfamethoxazole (SMX)/ Trimethoprim (TMP):
-Brand
-ROA
-Coverage
-Typical Indications
Brand: Bactrim, Bactrim DS
ROA: PO or injection
Coverage:
-GP: Staphylococi (including MRSA), S. pneumoniae –> group A streptococcus activity UNRELIABLE
-GN: H. influenzae, E. coli, Protekus, Klebsiella, Enterobacter, SHIGELLA, SALMONELLA, STENOTROPHOMONAS
-Opportunistic Inections: Nocardia, Pneumocystitis, Toxoplasmosis
-Does NOT cover: Pseudomonas, Enterococci, Atypicals, Anaerobes
Typical Indications:
-Severe infections
-Uncomplicated UTI
-Pneumocystis Pneumonia (PCP) prophylaxis or treatment
Sulfamethoxazole/Trimethoprim: Dosing
-Single Strength (SS)
-Double Strength (DS)
-Is dosing based on SMX or TMP?
-Dosing for uncomplicated UTI
-Dose frequency for pneomocystits pneumonia prophylaxis
SS: 400mg SMX / 80mg TMP
DS: 800 mg SMX / 160mg TMP
**ALL products formulated as SMX:TMP 5:1 ratio
Dosing: based on TMP
-Uncomplicated UTI: 1 DS tablet PO BID x3D
-PCP prophylaxis: QD dosing
Sulfamethoxazole / Trimethoprim:
-AVEs
-Warnings
-CIs
-Monitoring
-DDIs
AVEs: PHOTOSENSITIVITY, HYPERKALEMIA, CRYSTALLURIA (take with 8oz water), N/V/D, anorexia, skin RASH (fairly common along with hives), decreased folate, false elevations in SCr (due to inhibition of creatinine tubular secretion), renal failure
Warnings:
-Blood dyscrasias (agranulocytosis, aplastic anemia)
-Skin rxns (SJS/TEN), thrombotic thrombocytopenia purpura (TTP)
-Hemolytic anemia (can be immune-mediated w/ + Coombs test or G6PD deficiency)
-Hypoglycemia, thrombocytopenia
-Pregnancy: congenital defects from folic acid blockage (use if benefit outweights risk)
CIs: SULFA allergy, anemia from folate deficiency, renal/hepatic disease, infants <2 months
Monitoring: renal fxn, electrolytes, CBC, folate
DDIs:
-CYP2C9 inhibitor: can increase INR with warfarin
-Hyperkalemia risk with renal dysfunction or in combo with ACEIs, ARBs, aliskiren, aldosterone receptor antagonists, K-sparing diuretics, cyclosporine, tacrolimus, NSAIDs, drospirenone-containing oral contraceptives, or canagliflozin
-Bactrim can enhance toxic effects of methotrexate
-Bactrim effects can be diminished with leucovorin or levoleucovorin
Vancomycin:
-Brand
-ROA
-Coverage
-Typical Indications
-When to consider alternative ABX?
Brand: Vancocin
ROA: PO or IV
-PO has poor bioavailability (LARGE compound that cannot absorb across GI)
Coverage: GP ONLY
-Staphylococcus (including MRSA), streptococci, enterococci (NOT VRE)
-C. difficle (PO ROUTE ONLY)
Typical Indications:
-C. difficle
-Serious MRSA infections: bacteremia, sepsis, endocarditis, pneumonia, osteomyelitis, meningitis
-Other infections: UTIs, skin infections
Consider alternative when: MRSA MIC >/=2 mcg/mL
Vancomycin:
-Dosing for Systemic Infections
-Dosing for C. difficle
-Renal dose adjustments
-Warnings
Systemic Infection: 15-20mg/kg IV Q8-12H
-Dose based on TOTAL body weight
-CrCl 20-49mL/min: Q24H
-AMC/MIC ratio of 400-600 or steady state trough of 15-20mcg/mL (drawn 30 minutes before 4th or 5th dose) for serious infections
-Other infections (UTI, skin): goal trough of 10-15 mcg/mL
C. difficle: 125mg PO QD x10D
-500mg QID for severe, complicated disease in combo w/ IV metronidazole
-No renal dose adjustments
Warnings:
-Ototoxicity and nephrotoxicity: caution with other meds w/ same toxicities or w/ prolonged high serum concentrations
-IV formulation NOT effective for C.diff (does NOT cross GI tract)
-Vancomycin infusion rxn: maculopapular rash, hypotension, flushing, chills –> do NOT infuse faster than 1 gram per hour
Lipoglycopeptides:
-Drugs/Brands
-ROA/dosing frequency
-Typical Indications
Drugs: telavancin (Vibativ), ortivancin (Orbactiv, Kimyrsa), dalbavancin (Dalvance)
ROA: IV
-Oritavancin, dalbavancin: single-dose regimen
Typical Indications: similar coverage to vancomycin
-Skin and soft-tissue infections (SSTIs)
-Televancin: HAP and VAP
Lipoglycopeptides:
-Warnings
-CIs
-BBWs
Warnings:
-Infusion rxn (similar to vancomycin) w/ rapid administration
-Ortivancan, dalbavancin: FALSELY elevate PT/INR, but do NOT increase bleeding risk
-Televancin: QT prolongation (avoid other QT-prolonging medications)
-Ortivancin: use different ABX if osteomyelitis or suspected
-Dalbavancin: increases ALTs >3x ULN
CI:
-Televancin: concurrent use w/ IV UFH
-Ortivancin: do NOT use IV UFH for 120 hours (5 days) after administration due to interference w/ aPTT results (can increase PT/INRT up to 12 hours as well)
BBW:
-FETAL risk: obtain pregnancy test prior to therapy
-NEPHROTOXICITY: increased mortality due to renal impairment compared to vancomycin
Daptomycin:
-Brand
-ROA, compatible with _______
-Typical Indications
-AVEs
-Warnings
-Monitoring
Brand: Cubicin
ROA: IV
-compatible w/ NS and LR (no dextrose)
Typical Indications: SSTIs, bloostream infections/endocarditis
-do NOT use in pneumonia (does NOT penetrate lungs)
AVEs: increased CPK, abdominal pain, chest pain, edema,. HTN, AKI
Warnings:
-Myopathy and rhabdomyolysis: D/C in pts w/ s/s/sx and CPK >1000units/L or asymptomatic w/ CPK >2000unilts/L –> consider temporarily withholding other drugs that cause muscle damage (ex. statins) during TX
-Can falsely elevate PT/INR (NO bleeding risk)
-Peipheral neuropathy
-DRESS, eosinophilic pneumonia: generally 2-4 weeks after TX
Monitoring: CPK weekly (more frequently if on statin or w/ renal impairment), muscle pain/weakness, s/sx of neuropathy, dyspnea
Linezolid:
-Brand
-Drug class
-IV to PO ratio
-Administration considerations
-Coverage
-Typical Indications (contrast to tedizolid)
Brand: Zyvox
Drug class: oxazolidinone
IV to PO ratio: 1:1 -> NO renal dose adjustments
Administration: suspension should NOT be shaken
Coverage: vancomycin coverage + VRE
Typical indications: SSTIs, VRE infections, pneumonia, bloodstream infections
-Tedizolid: only for SSTIs
Linezolid:
-AVEs
-Warnings
-CIs
-Monitoring
-DDIs
AVEs: decreased PLTs/Hgb/WBCs, HA, N/D, increased LFTs
Warnings:
-Duration-related myleosupression (thrombocytopenia, anemia, leukopenia) when used > 14 days
-Peripheral and optic neuropathy when used >28 days
-Serotonin syndrome
-Hypoglycemia, hyponatremia, seizures, lactic acidosis, increased BP (caution in uncontrolled HTN or hyperthyroidism)
CIs: within 2 weeks of MAOI use
Monitoring: weekly CBC, HR, BP, BG in DM, visual function
DDIs: linezolid is a reversible MOAI (avoid tyramine-containing foods and serotonergic drugs), exacerbate hypoglycemia episodes (caution in insulin or oral hypoglycemics - sulfonylureas)
Tigecycline:
-Brand
-MOA
-ROA
-Administration considerations
-Coverage
-Typical indications
-AVEs
-Warnings
-BBW
Brand: Tygacil
MOA: glycycyline that binds to 30S ribsomal subunit to inhibit protein synthesis
ROA: IV
Administration: solution should be yellow-orange in color
Coverage: broad spectrum (MRSA, VRE, gram-negative, anaerobes, and atypicals)
-NO activity against 3 P’s: Pseudomonas, Proteus, and Providencia
Typical indications: complicated SSTIs, intra-abdominal infections, CAP
-do NOT use for bloodstream infections
AVEs: N/V (can be intractable)/D, HA, dizziness, increased LFTs, rash/severe skin rxns
Warnings: anaphylactic rxns (avoid in tetracycline-class allergy), hepatotoxicity, pancreatitis, photosensitivity, bone growth suppression and teeth discoloration (<8 yo)
BBW: increased risk of death –> only use when alternative TX not suitable
Polymyxins:
-Drugs/Brands
-MOA
-ROA
-Typical indications
-Warnings
-DDIs
Drugs: colistimethate (Coly-Mycin M), polymyxin B
MOA: cationic detergents that damage bacterial cytoplasmic membrane, causing leakage of intracellular substances and death
-Colistimethate is prodrug convertexd to colistin
ROA: IV, IM (colistimethate), inhalation (colistimethate)
Typical indications: gram-negative (Enterobacter, E. coli, Pseduomonas)
-NO activity against Proteus
-Due to toxicity risk, primarily for MDR gram-negative pathogens in combo w/ other ABXs
Warnings: dose-dependent nephrotoxicity, neurotoxicity (dizziness, HA, tingling, oral paresthesia, vertigo, respiratory paralysis from neuromuscular blockade
-Warnings are a BBW in polymyxin B
DDIs: additive nephrotoxicity w/ aminoglycosides, ampB, cisplatin, cyclosporine, loop diuretics, NSAIDs, radiocontrast dye, tacrolimus, vancomycin
What is chloramphenicol (MOA and use)?
MOA: reversibly binds to 50S subunit of bacterial ribosome, inhibiting protein synthesis
Has gram-positive, gram-negative, anaerobe, and atypical coverage, BUT due to AVEs rarely used (ex. fatal blood dyscrasias - asplastic anemia, pancytopenia, and Gray syndrome - circulatory collpase, cyanosis, and acidosis)
Clindamycin:
-Brand
-MOA
-ROA
-Administration considerations
-Coverage
-AVEs
-Warnings
-BBW
Brand: Cleocin, Cleocin-T, Clindagel, Clindesse, Clindacin Pac, Clindacin-P
MOA: lincosamide that binds to 50S subunit of ribosome to prevent protein synthesis
ROA: PO, topical (Cleocin-T, Clindagel), vaginal (Clindesse)
Administration:
-NO renal dose adjustments
-Induction test (D-test) should be perfomed on S. aureus (flattened zone between disks = positive = clindamycin resistance)
Coverage: most gram-positive bacteria (CA-MRSA, anaerobes)
-NO coverage on Enterococcus, gram-negative
AVEs: N/V/D, rash, urticaria, increased LFTs (rare)
Warnings: severe or fatal skin rxns
BBW: colitis (C. difficile)
Metronidazole:
-Brand
-MOA
-ROA
-IV:PO ratio
-Coverage
-Typical indications
Brand: Flagyl, Likmz, MetroCream, Metrogel, MetroLotion, Noritate, Nuvessa, Vandazole
MOA: induce loss of helical DNA structure and strand breakage, preventing protein synthesis
ROA: PO, IV, topical (Metrogel, MetroLotion, Noritate), vaginal (Nuvessa, Vandazole)
IV:PO ratio: 1:1
Coverage: anaerobes, protozoal organisms
Typical indications: bacterial vaginosis, trichomoniasis, giardiasis, amebiasis, C. difficile, in combo for intra-abdominal infections
Metronidazole:
-AVEs
-Warnings
-CIs
-BBW
-DDIs
AVEs: metallic taste, HA, nausea, furry tongue, dizziness, rash/severe skin rxns
Warnings: CNS effects (seizures, peripheral neuropathy), aseptic meningitis, encephalopathy, optic neuropathy
CIs: pregnancy (1st trimester), use of alcohol or propylene glycol-containing products during TX or within 3 days of D/C (disulfiram rxn), use of disulfiram in past 2 weeks
BBW: possibly carcinogeic (based on animal data)
DDIs: alcohol, weak inhibitor of CYP2C9 (can increase INR in pts taking warfarin)
What are drugs similar to metronidazole and their uses?
Tinidazole: activity limited to protozoa (glardiasis, amebiasis), trichomoniasis, and bacterial vaginosis
Secnidazole: only indicated in bacterial vaginosis and trichomoniasis
-Do NOT use in vulvovaginal candidiasis
Lefamulin:
-Brand
-MOA
-ROA
-Typical indications
-AVEs
-Warnings
-CIs
Brand: Xenleta
MOA: first-in class pleuromutilin that inhibits protein synthesis via binding to peptidyl transferase center of 50S ribosomal subunit
ROA: PO, IV
Typical indications: ??
AVEs: D/N, injection site rxns
Warnings: pregnancy (teratogenic), QT prolongation
CIs: use w/ CYP3A4 substrates that prolong QT interval
Fidaxomicin:
-Brand
-MOA
-ROA
-Typical indications
-AVEs
-Warnings
Brand: Dificid
MOA: inhibits RNA polymerase, inhibiting protein synthesis and cell death
Typical indication: C. diff
AVEs: N/V, abdominal pain, GI bleeding, anemia
Warnings: NOT effective for systemic infections (absorption minimal)
Rifaximin:
-Brand
-MOA
-ROA
-Typical indications
-AVEs
Brand: Xifaxan
MOA: inhibits bacterial RNA synthesis vial binding to DNA-dependent RNA polymerase
ROA: PO
Typical indications: traveler’s diarrhea, hepatic encephalopathy, IBD-D
-NOT effective for systemic infections (<1% absorption)
-Off label: C. difficle (third or subsequent recurrence)
AVEs: peripheral edema, dizziness, HA, nausea, abdominal pain, rash, pruritus
Fosfomycin:
-Brand
-MOA
-ROA/Dose
-Coverage
-Typical indications
-AVEs
Brand: Monurol
MOA: inactivates enzyme, pyruval transferase which is critical in synthesis of cell walls
-Concentrates in urine
Dose: packet granules (3 grams/packet) –> 3 grams PO once mixed in 3-4 oz of cold water
Coverage: E. coli (including ESBL), E. faecalis (including VRE)
Typical indication: uncomplicated UTI
AVEs: HA, D/N
Nitrofurantoin:
-Brand
-MOA
-ROA
-Typical indications
-Dosing
-AVEs
-Warnings
-CIs
Brand: Macrobid, Macrodantin
MOA: bacterial cell wall, DNA, RNA, and protein synthesis inhibitor
ROA: PO
Typical indication: uncomplicated UTI (cystitis only; E. coli, Klebsiella, Enterobacter, S. aureus, Enterococcus including VRE)
Dosing:
-Macrobid: 100mg PO BID x5D
-Macrodantin: QID
AVEs: GI upset (take CF), HA, rash, brown urine discoloration (harmless)
Warnings: optic neuritis, hepatotoxicity, peripheral neuropathy, pulmonary toxicity, G6PD deficiency (hemolytic anemia - do NOT use if known deficiency)
CIs:
-Renal impairment (CrCl <60mL/min): inadequate urine concetration and risk for accumulation of neurotoxins
-Hx of cholestatic jaundice/hepatic dysfunction
-Pregnancy
Mupirocin: Brand, ROA, and typical indication
Brand: Bactroban
Nasal ointment to eliminate MRSA colonization of nares
List ABXs that can be used for: MSSA
-Dicloxacillin, nafacillin, oxacillin
-1st and 2nd gen cephalosporins (ex. cephalexin, cefazolin)
-Augmentin, ampicillin/sulbactam
List ABXs that can be used for: MRSA and/or CA-MRSA
MRSA: vancomycin (consider alternative if MIC 2 or greater), linezolid, daptomycin (NOT for pneumonia), ceftaroline
CA-MRSA: SMX/TMP, doxycycline, clindamycin
List ABXs that can be used for: VRE
E. faecalis only: penicllin G, ampicillin
Cystitis: nitrofurnaoint, fosfomycin, doxycycline
Others: linezolid, daptomycin
List ABXs that can be used for: Atypicals
azithromycin, clarithromycin, doxycycline, minocycline, quinolones
List ABXs that can be used for: HNPEK
-Beta-lactam/beta-lactamase inhibitors
-Cephalosporins (1st gen covers PEK)
- Carbapenems
-Aminogylcosides, quinolones, Bactrim
List ABXs that can be used for: Pseudomonas
-Piperacillin/tazobactam, cefepime, ceftazidime, ceftazidime/avibactam, ceftolozane/tazobactam, carbapenems (except: ertapenem)
-Ciprofloxacin, levofloxacin, aztreonam, tobramycin
List ABXs that can be used for: CAPEs
piperacillin/tazobactam, cefepime, carbapenems, aminoglycosides
List ABXs that can be used for: ESBL-producing GNRs
carbapenems, ceftazidime/avibactam, ceftolozane/tazobactam
List ABXs that can be used for: CREs
ceftazidime/avibactam, colistimethate, polymyxin B, meropenem/vaborbactam, imipenem/cilastatin/relebactam
List ABXs that can be used for: Bacterioides fragilis
metronidazole, beta-lactam/beta-lactamase inhibitor, cefotetan, cefoxitin, carbapenems, moxifloxacin (reduced activity)
List ABXs that can be used for: C. difficle
vancomycin (PO), fidaxomicin, metronidazole
Storage Requirements for Liquid Oral ABXs:
-Refrigerate after reconstitution
-Refrigerate recommended
-Do NOT refrigerate
Refrigerate, required: penicilin VK, Augmentin, cephalexin, cefadroxil, cefpodoxime, cefprozil, cefuroxime, cefaclor, fidaxomicin, vancomycin PO, valganciclovir
Refrigerate, recommended: amoxicillin (improves taste), oseltamivir (increases shelf-life)
Do NOT refigerate: cefdinir, azithromycin, clarithromycin, clilndamycin, doxycycline, erythromycin, ciprofloxacin, levofloxacin, linezolid, metronidazole, nitrofurantoin, Bactrim, acyclovir, fluconazole, itraconazole, posaconazole, voriconazole, nystatin
Which IV ABXs should NOT be refrigerated?
- Metronidazole
- Moxifloxacin
- Bactrim
- Acyclovir
ABXs that do NOT require renal dose adjustment
- Anti-staphylococcal PCNs (ex. dicloxacillin, nafcillin)
- Azithromycin, erythromycin
- Ceftriaxone
- Clindamycin
- Doxycycline
- Metronidazole
- Moxifloxacin
- Linezolid
Most ABXs should be taken WITH FOOD to decrease GI upset. Which ones are to be taken OES?
- Ampicilllin oral caspules
- Levofloxacin oral solution
- Pencillin VK
- Tetracycline
- Doxycycline (Oracea brand)
- Rifampin
- Isoniazid
- Itraconazole oral solution
- Voriconazole
Which ABXs have 1:1 PO:IV ratios?
- Azithromycin
- Levofloxacin, moxifloxacin
- Doxycycline, minocycline
- Linezolid, tedizolid
- Metronidazole
- Bactrim
Which IV antimicrobials are compatible with dextrose only?
Bactrim, AmpB, pentamidine
Which IV antimicrobials are compatible with saline only?
ampicillin, ampicillin/sulbactrim, ertapenem
Which IV antimicrobials are compatible with NS/LR only?
caspofungin, daptomycin
Whichs IV antimicrobials require light protection during administration?
- Doxcycline
- Micafungin
- Pentamidine
Perioperative ABX Prophylaxis
1. What are the main pathogens for contamination during surgery?
- Preferred ABXs, alternatives, and ABXs to give in beta-lactam allergy in:
-Cardiac or vascular surgery
-Orthopedic surgey (ex. joint replacement or hip fracture repair)
-GI surgery (ex. appendectomy, colorectal) - When should the IV ABXs be given before, during and after surgery?
- Gram positive cocci (staphylococci and streptococci) –> in select surgeries such as intra-abdominal, gram-negative and anerobes
2.
-Cardiac or vascular: cefazolin or cefuroxime (preferred), clindamycin or vancomycin (beta-lactam allergy)
-Orthopedic: cefazolin (preferred), clindamycin or vancomycin (beta-lactam allergy)
-GI: cefazolin + metronidazole, cefotetan, cefoxitin, or ampicillin/sulbatam (preferred), clindamycin or metronidazole + aminoglycoside or quinolone (beta-lactam allergy)
3.
-Before: cefazolin or cefuroxime within 60 minutes of first incision; quinolone or vancomycin 120 minutes of first incision
-During: additional dose may be given for longer surgeries (>4 hours) or major blood loss –> ex. cefazolin T1/2 = 2 hours, redose Q4H
-After: NOT usually needed (if used, D/C within 24 hours)
Bacterial Meningitis:
-S/Sx
-Diagnosis
-Pathogens (consider pt population risk as well)
S/Sx: fever, HA, nuchal rigidity (stiff necK), altered mental status
-Other s/sx: chills, vomiting, seizures, characteristic rash, photophobia
Diagnosis: lumbar puncture (LP) - culture of cerebrospinal fluid (CSF), high CSF pressure (“opening pressure”) may also indicate infection
-Bacterial CSF: elevated WBCs and protein, decreasd glucose
Pathogens: menigitis is typically viral, but for bacterial:
-GP: cocci (groupB strep, Streptococcus pneumonia)
-GN: cocci (N. meningitidis), coccobacilli (H. influenzae), bacilli (E. coli)
-Listeria monocytogenes: higher risk in neonates, pts >50 yo, and immunocompromised
Bacterial Meningitis:
-What should be considered to administer prior to ABXs and why? When to D/C?
-Empiric TX
-Duration of TX
Dexamethasone IV: aminister 15-20 minutes prior to ABXs or with first dose to prevent neurological complications (ex. hearing loss) and death from excessive inflammation–> during empiric therapy, appropriate to adminster to all pts since causative species NOT known
-D/C if species to be identified is NOT S. pneumoniae
Empiric TX: higher doses, must penetrate BBB
-Age <1 month (neonates): ampicillin (Listeria coverage) + cefotaxime, ceftazidime, or cefepime +/- gentamicin
-Age 1 month - 50 yo: ceftriaxone + vancomycin
-Age > 50 yo: ampicillin (Listeria coverage) + ceftriaxone + vancomycin
Duration of TX:
-N. meningitidis, H. influenzae: 7 days
-S. pneumoniae: 10-14 days
-GroupB strep (S. agalactiae): 14-21 days
-L. monocytogenes, GNRs: at least 21 days
Bacterial Acute Otitis Media (AOM):
-S/Sx
-Pathogens
-When to observe
-TX: first line, alternatives, in TX failure
S/Sx: rapid onsets of bulging tympanic (eardrum) membranes, otorrhea (middle ear effusion/fluid), otalgia (ear pain), fever, crying, tugging/rubbing ears
Pathogens: mostly caused by viruses, but for bacterial:
-S. pneumoniae, H. influenzae, or Moraxella catarrhalis
Observation: for 2-3 days if symptoms are non-severe (otalgia <48 hours, no otorrhea, temp <102.2F or 39C) AND
-Age 6-23 months: symptoms in one ear only
-Age 2 yo or older: symptoms in one or both ears
-ALWAYS treat <6 months
TX: higher doses to penetrate ear
-First line: amoxicillin 90mg/kg in 2 divided doses OR Augmentin 90mg/kg with 6.4mg/kg/day of clavulanate in 2 divided doses (keep ratio of amoxicillin:clavulanate 14:1 to minimize toxicity)
-Alternatives (non-severe PCN allergy: mild, non-itchy rash): cefdinir, cefuroxime, cefpodoxime, or ceftriaxone
-TX failure (no imporvement after 2-3 days): Augmentin if amoxicillin failed or ceftriaxone IM
Upper Respiratory Tract Infections (URTIs): Common Cold
-Most common pathogen
-S/sx
-Criteria for TX
-TX
Pathogen: respiratory viruses (rhinovirus, seasonal coronavirus)
S/Sx: sneezing, runny nose, mild sore throat, cough, congestion
-Fever usually absent or low-grade (<101F), no myalgias
Criteria for TX: non –> generally resolves within a few days
TX: symptomatic care (analgesics, decongestants, cough suppressants, expectorants, and.or antihistamines)
Upper Respiratory Tract Infections (URTIs): Flu
-Most common pathogen
-S/sx
-Criteria for TX
-TX
Pathogen: influenza virus
S/Sx: sudden onset fever, chillls, fatigue, myalgia, dry cough, sore throat, HA
-Symptoms are more severe than a common cold
Criteria for TX: suspected or confirmed infection AND
-Symptoms <48 hours OR
-Severe illness OR
-Symptoms plus risk factors for complications
TX: symptomatic care +/- antivirals (oseltamivir, baloxavir marboxil)
Upper Respiratory Tract Infections (URTIs): Pharyngitis (“Strep Throat”)
-Most common pathogen
-S/sx
-Criteria for TX
-TX: first line, alternatives
Pathogen: respiratory viruses, group B strep (S. pyogenes)
S/Sx: sore throat, fever, swollen lymph nodes, white patches (exudates) on tonsils
-Absence of runny nose, cough, or congestion
Criteria for TX: rapid antigen test (tonsil swab) or thorate culture (+) for S. pyogenes
TX: penicillin VK or amoxicillin
-Mild PCN allergy: 1st or 2nd gen cephalosporin
-Severe rxn to PCN: macrolide (clarithyromycin, azithromycin) or clindamycin
Upper Respiratory Tract Infections (URTIs): Acute sinusitis
-Most common pathogen
-S/sx
-Criteria for TX
-TX
Pathogen: respiratory viruses (S. pneumoniae, H. influenzae, M. catarrhalis)
S/Sx: nasal congestion, purulent nasal discharge, facial/ear/dental pain or pressure, HA, fever
-Absence of cough
Criteria for TX:
-10 days or longer w/ persistent symptoms OR
-3 days or longer w/ severe symptoms (face pain, purulent nasal discharge, temp >102F) OR
-Worsening symptoms after initial improvement
TX: Augmentin or symptomatic care for up to 7 days w/ decongestants, antihistamines, expectorants, and/or analgesics
-Macrolides NOT recommended due to poor coverage of S. pneumoniae
Lower Respiratory Tract Infections: Acute Bronchitis
-S/Sx
-Pathogen
-Diagnosis
-TX
S/Sx: non-productive or productive cough lasting 1-3 weeks, chest wall tenderness, wheezing, rhonci
-Systemic symptoms (fever, chills, mailase) are rare
Pathogen: Usually preceded by URTI virus (ex. rhinovirus, coronavirus, influenza)
-Rarely bacterial: S. pneumoniae, H. influenzae, atypicals (Myclopasma pneumonae)
Diagnosis: ruling out other causes; chest x-ray is typically normal
TX: ABXs are NOT recommended (self-limiting), supportive care
Lower Respiratory Tract Infections: Pertussis
-S/Sx
-Pathogen
-Diagnosis
-TX
S/Sx:
-Catarrhal phase (week 0-2): mild cough/rhinitis
-Paroxysmal phase (week 2-8): severe bouts of coughing (whooping cough)
-Convalescent (week 8-12+): gradual resolution
Pathogen: Bordetella pertussis
Diagnosis: nasopharyngeal swab culture or PCR
TX: highly contangious –> treat w/ macrolides (azithromycin, clarithromycin)
Lower Respiratory Tract Infections: Acute Bacterial Exacerbation of COPD
-S/Sx
-Pathogen
-Diagnosis
-TX
S/Sx: increased dsypnea, increased sputum volume, increased sputum purulence
-Symptoms that necessitates a change in COPD medications
Pathogen: H. influenzae, M. catarrhalis, S. pneumoniae
-Other causes: environmental pollution
Diagnosis: increase in symptoms that worsen over <14 days
TX: supportive TX (oxygen, short-acting inhaled brochodilators, IV or PO steroids, ABXs (Augmentin, aizthromycin, doxycycline, or respiratory quinolone) for 5-7 days IF on one of the following:
-All three symptoms present (dyspnea, sputum volume, sputum purulence)
-Increased sputum purulence with an additional symptom
-Mechanically ventilated
Lower Respiratory Tract Infections: Community-acquired pneumonia (CAP)
-S/Sx
-Pathogen
-Diagnosis
S/Sx: SOB, fever, cough with purulent symptoms, pleurtic chest pain, rales, tachypnea, decreased heart sounds, elevated WBCs
Pathogen: S. pneumoniae, H. influenzae, M. pneumoniae, C. pneumoniae, Legionella
Diagnosis: chest X-ray - inflitrates/opacities/consolidations
Lower Respiratory Tract Infections: Community-acquired pneumonia (CAP): Outpatient TX and TX duration
-Healthy, no comorbidities: amoxicillin high dose (1 gram TID) OR doxycycline OR macrolide (azithromycin or clarithromycin) if local pneumococcal resistance is <25%
-High risk (with comorbidities): beta lactam (Augmentin, cefpodoxime, cefuroxime) + macrolide or doxycycline OR respiratory quinolone monotherapy (moxifloxacin or levofloxacin)
**Comorbodities: chronic heart, lung, liver, or renal disease; DM; alcohol use disorder; malignancy; asplenia
**Erythromycin: NOT recommended due to poor tolerance and DDIs
TX duration: 5-7 days usually
Lower Respiratory Tract Infections: Community-acquired pneumonia (CAP): Inpatient TX and TX duration
-Non-severe (admission to general medicine unit): beta lactam (ceftriaxone, ceftaroline, ampicillin/sulbactam) + macrolide or doxycycline OR respiratory quinolone monotherapy
-Severe (admission to ICU): beta lactam + macrolide OR beta-lactam + respiratory quinolone (NO quinolone monotherapy)
-Risk for MRSA (prior respiratory isolation or positive nasal swab): add vancomycin or linezolid
-Risk for Pseudomonas (prior respiratory isolation): beta-lactam w/ Pseudomonas activiy (ex. piperacillin/tazobactam, cefepime, ceftazidime, imipenem/cilastin, meropenem)
-Hospitalization and use of parenteral ABXs in past 90 days: use regimen active against both MRSA and Psuedomonas
TX duration: 5-7 days usually
Lower Respiratory Tract Infections: Hospital-acquired and Ventilator-associated pneumonia (HAP/VAP)
-Criteria for HAP vs. VAP
-S/Sx
-Pathogen
-Empiric TX
HAP: onset >48 hours after hospital admission
VAP: occurs >48 hours after start of mechanical ventilation
S/Sx: SOB, cough w/ purulent sputum, pleuritic chest pain, fever, elevated WBCs
-Chest X-ray: consolidation or infiltrates
-Physical exam: rales, tachypnea, decreased breath sounds
-Additional VAP signs: increased secretions (suction requirements), increased ventilation needs (FiO2)
Pathogen: nosocomial (MSSA, MRSA, Pseudomonas, MDR GNRs risk - E. coli, Acineobacter, Enterbacter)
Empiric TX: ALL need MSSA and Pseudomonas coverage (ex. cefepime, piperacillin/tazobactam, levofloxacin)
-MRSA risk (IV ABX use in past 90D, MRSA prevalence in hospital unit >20% or unknown, prior MRSA infection, or positive MRSA nasal swab): add vancomycin or linezolid
-Use two ABXs for Pseudomonas if risk for MDR GNR (IV ABX use in past 90D, prevalance in hospital unit >10%, hospitalized 5 days or more prior t onset of VAP): beta-lactam + other agent (don’t use TWO beta-lactams for Pseudomonas - fluroquinolone, aminoglycoside)
Lower Respiratory Tract Infections: Latent Tuberculosis
-Pathogen
-Tuberculin skin test (TST)
-Interferon-gamma release assay (IGRA)
-Transmission
Pathogen: Mycobacterium tuberculosis
Tuberculin skin test (TST) also called purfied protein derivative (PPD) test: intradermal solution injected and inspected for induration (raised area) 48-72 hours later, positive IF:
-Close contact of active TB, HIV infection, immunosuppression: 5mm or greater induration
-Immigrants w/ high burden countries, clinical risks (IV drug use, DM), residents/employees of high-risk congregate settings (prisons, healthcare facilities, homeless sheltors): 10mm or greater induration
-Pts with NO risk factors: 15mm or greater induration
IGRA blood test: preferred in pts w/ hx of BCG vaccination
Transmission: NOT contagious as latent
Lower Respiratory Tract Infections: Latent Tuberculosis TX
Shorter duration (3-4 months) preferred due to higher completion rates and less hepatotoxicity risk
-INH + rifapentine Qweekly x12 weeks via directly observed therapy (DOT) or self-administered (do NOT use in pregnancy: fetal risk unknown w/ rifapentine)
-INH + rifampin QD x3 months
-Rifampin QD x4 months
-INH QD x6-9 months (may be preferred in HIV - less DDIs, 9 months recommended)
**Rifamycin-based regimens: check for DDIs
Lower Respiratory Tract Infections: Active Tuberculosis
-S/Sx
-Transmission
-Diagnosis
S/Sx: cough > 2-3 weeks in duration, hemoptysis, purulent sputum, fever, night sweats, unintentional weight loss
Transmission: highly contagious via aerosolized droplets (hospitalization requires negative-pressure room and masks for healthcare workers)
Diagnosis: sputum culture or PCR (BUT slow to grow - could take 6 weeks), acid fast bacilli (AFB) smear (NOT selective for TB), chest x-ray w/ consolidation or cavitation (empty space) to confirm positive TST or IGRA
Lower Respiratory Tract Infections: Active Tuberculosis
-General TX
-TX in multidrug resistant TB (MDR-TB) and extremely drug-resistant TB (XDR-TB)
TX:
-Intensive phase: four drugs (RIPE: rifampin, isoniazid, pyrazinamide, ethambutol) x 2 months
-Continuation phase: two drugs (commonly rifampin and isonazid) x 4 months
-Direct observed therapy (DOT) used to increase medication adherence and preferred in certain populations (homless, drug-resistant disease, poor adherence, positive sputum smearsa nd delayed culture positivity) –> alternative dosing regimens (ex. 2-3x/week) can be used
TX in resistance:
-MDR-TB: resistant to BOTH rifampin or INH (second line drugs up to 24 months: quinolones - moxifloxacin or levofloxacin, injectables - streptomycin, amikacin, or kanamycin)
-XDR-TB: bedaquiline can be sued (BBW: QT prolongation and increased risk of death), pretomanid (approved for both MDR-TB and XDR-TB in combo w/ bedaquiline and linezolid - many AVES: peripheral neuropathy, optic neuropathy, myleosuppression, QT prolongation)
Considerations in RIPE Therapy for Active TB
-Isoniazid
-Pyrazinamide
-Ethambutol
Isonazid:
-Use pyroxidine (vitamin B6) 25-50mg QD to decrease risk of INH-associated peripheral neuropathy
-AVEs: increased LFTs, DILE, hemolytic anemia (positive Coombs test)
-BBW: hepatitis (severe and fatal)
Pyrazinamide:
-AVEs: increased LFTs, hyperuricemia/gout, GI upset, malaiase, arthralgia, rash
-CI: acute gout, severe hepatic damage
Ethambutol:
-AVEs: increased LFTs (dose-related), confusion, hallucinations, decreased visual acuity, partial loss of vision/blind spot and/or color blindness (usually reversible)
-CI: optic neuritis
Rifampin:
-Brand
-AVEs
-CI
-DDIs
Brand: Rifadin
AVEs: increased LFTs, hemolytic anemia (positive Coombs test), flu-like syndrome, GI upset, rash/pruritus
-Orange-red discoloration of body secretions (saliva, urine, sweat, tears): can stain contact lenses, clothing, and bedsheets
CI: concurrent use w/ protease inhibitors
DDIs: potent inducer of CYP1A2, 2C8, 2C9, 2C19, 3A4, and P-gp
-Decreases: protease inhibitors (substitute rifabutin), warfarin (very large decrease in IRN common - need large dose increases), OCs (requires backup contraception method)
-do NOT use w/ apixiban, rivaroxaban, edoxaban, or dabigatran (failure of therapy)
-Always screen for DDIs
-Rifabutin has fewer interactions and can replace rifampin in some cases
Spontaneous Bacterial Peritonitis (SBP): define, diagnosis, emperic TX, secondary prophylaxis
SBP: infection of peritoneal space that often occurs in pts w/ cirrhosis and ascites
-Paracentesis: ascitic fluid sample >/=250 cells/mm3 PMN (polymorphonuclear leukocytes)
Emperic TX: ceftriaxone or cefotaxmine x5-7D (targets most likely pathogens: steptococci, Proteus, E. coli, Klebsiella
Alternative: carbapenem in critically ill or risk for MDR
Secondary prophylaxis: ALL pts who have received initial SBP epsidoe should be prescribed Bactrim or quinolone to decrease subsequent infections (also indicated in ascitic fluid protein <1.5g/dL and impaired renal or heaptic function)
What are other types of intra-abdominal infections and the general TX besides SBP?
Other intra-abdominal infections: appendicitis, cholecystitis (inflammation of gallbladder), cholangitis (inflammation of bile duct), secondary peritonitis, diverticulitis
-If abcess present, drain (source control)
-Infections usually polymicrobial (streptococci, enteric gram-negatives, anaerobes - ex. Bacterioides fragilis): often a single ABX (if NO anaerobe coverage, add metronidazole) for 4-5 days until source control accomplished
-Risk of MDR pathogens (critically ill, hospitalized >48 hours, ABX in past 90D): consider coverage of Psedumonas or other resistant organisms
General TX Options:
-Cover PEK, anaerobes, and streptococci (low risk): ertapenem, moxifloxacin, cefuroxime or ceftriaxone + metronidazole, ciprofloxacin or levofloxacin + metronidazole
-Cover PEK, Pseudomonas, Enterobacter, anaerobes, streptococci, and entercocci (high risk: critically ill, received ABXs in past 90 days, or known colonization of prior infection) : carbapenem (except ertapenem), piperacillin/tazobactam, cefepime or ceftazidmine + metronidazole
Infective Endocarditis
-S/Sx
-Pathogen
-Diagnosis
-What makes TX more difficult?
S/Sx: fever w/ or w/o heart murmur, signs of thromboembolism, elevated WBCs
Pathogen: Staphylococci, Streptococci, and Enterococci
Diagnosis: echocardiogram (vegetation on valve) and positive blood cultures
TX challenges: vegetation acts as a protective film - difficult for ABXs to penetrate, high concentration of bacteria present, and slow rate of bacterial growth
Infective Endocarditis
-Empiric TX
-Definitive TX
Empiric TX: often includes vancomycin + ceftriaxone
Definitive TX:
-Viridans group streptococci: PCN or ceftriaxone +/- gentamicin (beta-lactam allergy: use vancomycin monotherapy)
-MSSA: nafcillin or cefazolin + gentamicin and rifampin if prosthetic valve (beta-lactam allergy: vancomycin +/- gentamicin and rifampin —> prosthetic valves)
-MRSA: vancoymcin + gentamicin and rifampin if prosthetic valve
-Enterococci: for both naive and prosthetic valve, PCN or ampicillin + gentamicin OR ampicillin + high-dose ceftriaxone (beta-lactam allergy: vancomycin + gentamicin, VRE: daptomycin or linezolid)
**Gentamicin added for synergy (beta lactam penetrates cell wall, allowin gentamicin to enter to work) in infections more difficult to eradicate (peak level: 3-4 mcg/mL, trough <1 mcg/mL)
Infective Endocarditis: Dental prophylaxis (when indicated and ABX options)
Dental prophylaxis: indicated in pts with dental work needed (manipulation of gingival tissue or near root of tooth - tooth extraction, root canal, abscess drainage) + select cardiac conditions (ex. artificial/prosthetic heart valve or heart valve repiared w/ artifical material, hx of endocarditis, heart transplant w/ abnormal heart valve function, certain congenital heart defects including heart/heart valve disease)
-ALL: give as single dose 30-60 minutes prior to dental procedure
-First-line: amoxicillin 2 grams PO
-Unable to take PO: ampicillin IV/IM OR cefazolin or ceftriaxone IM/IV
-PCN allergy: azithromycin or clarithromycin PO OR doxycycline PO
Skin and Soft-Tissue Infections (SSTIs): Impetigo
-Is this a superficial infection?
-Pathogens
-S/Sx
-TX
Superficial infection
Pathogen: Group A streptococcus (mostly S. pyogenes), S. aureaus (most often MSSA)
S/Sx: blister-like rash (may be itchy or painful) usually around nose, mouth, hands, or arms; pustules rupture and produce thick-yellowish, clear fluid that dries and forms honey-colored crusts over area
-Common in children
TX: warm, wet compresses to remove dried crusts (do NOT share towels, sheets, or clothing and wash in hot water)
-Limited, localized: apply topical ABX usually mupirocin (alternatives: retapumulin - Altabax, ozenoxacin -Xepi)
-Numerous, extensive lesions: cephalexin or dicloxacillin
Skin and Soft-Tissue Infections (SSTIs): Folliculitis/Furnucle/Carbuncle
-Is this a superficial infection?
-Pathogens
-S/Sx
-TX
Superficial infection
Pathogen: S. aureus, including CA-MRSA
S/Sx:
-Folliculitis: inflammation in hair follicles (red pimples)
-Furuncle (boils): purulent infection of hair follicle
-Carbuncle: group of infected furuncles
TX:
-Small furuncles, folliculitis: warm compresses to decrease inflammation and improve drainage
-Large furuncles, carbuncles: incision and drainage +/- ABXs (Bactrim or doxycline)
-Occassionally, folliculitis is due to fungal infection and can be treated w/ ketoconazole cream
Skin and Soft-Tissue Infections (SSTIs): Mild Cellulitis (Non-purulent)
-Is this a superficial infection?
-Pathogens
-S/Sx
-TX
NO - penetrates subcutaneous tissue
Pathogens: Streptococci including S. pyogenes (GRoup A Streptococcus), S. aureus
-Purulent more often S. aureus (MSSA or MRSA)
S/Sx: occurs on legs, generally unilateral, but can rapidly spread/expand
-Mild symptoms: localized pain, swelling, redness, warmth
TX: ABX should be active against streptococci and MSSA –> must have NO signs of systemic s/sx (WBCs </=12000 or >/=4000; temp </=100.4, HR </=90)
-Cephalexin, Dicloxacillin, or clindamycin if beta-lactam allergy
-Duration of usually 5 days (longer if NO improvement)
Skin and Soft-Tissue Infections (SSTIs): Abscess (Purulent)
-Pathogens
-S/Sx
-TX
Pathogen: S. aureus, including CA-MRSA
S/Sx: initially appears as localized fluid collection
TX: source control
-ABXs with MSSA and MRSA coverage: Bactrim, doxycycline, minocycline, clindamycin, linezolid
-If culture shows just MSSA: cephalexin
-If recurrent MRSA infections, consider nasal decolonization w/ nasal mupirocin and skin decolonization w/ chlorhexidine or diluent bleach
Skin and Soft-Tissue Infections (SSTIs): TX in severe purulent or necrotizing fascilitis (severe nonpurulent) infections
Severe purulent: ABXs w/ MRSA activity (vancomycin w/ goal trough of 10-15 mcg/mL, daptomycin, linzeolid)
-Alternatives: ceftaroline, tedizolid, televancin
-Once clinically stable, transition to PO ABXs
-Duration of therapy 7-14 days
Necrotizing Fascilitis: life-threatening and fast-moving that can destroy tissue and penetrate down into muscle –> emergency TX in hospital
-Urgent surgical debridement
-Broad empiric ABXs: vancomycin or daptomycin + beta-lactam (piperacillin/tazobactam, meropenem) + clindamycin (to suppress streptococcal toxin production)
Diabetic Foot Infections
-Pathogens
-TX in mild vs. moderate-severe
-TX duration in moderate-severe
Pathogens:
-Aerobic: S. aureus (including MRSA), Group A streptococcus, Viridans group streptococci, S. epidermidis, E. coli, Klebsiella pneumoniae, Proteus mirabilis, Enterobacter clocacae, Pseudomonas (if significant water exposure)
-Anaerobic (if limb ischemia or necrosis present): Peptostreptococcus, C. perfringens, Bacteriodies fragilis and others
Mild: w/o systemic symptoms –> can treat similarily to mild SSTIs
Moderate-severe: start IV then transition to PO
-NO MRSA activity needed: ampicillin/sulbactam, ertapenem, ceftriaxone, levofloxacin or moxifloxacin
-Pseudomonas and/or MDR gram-negative activity needed: piperacillin/tazobactam, cefepime, meropneem, doripenem, or imipenem/cilastin
-MRSA activity needed: add vancomycin, daptomycin, or linezolid
-Anaerobic activity needed: use regimen w/ anaerobic activity (ex. beta-lactam/beta-lactamase, carbapenem) OR add metronidazole
TX duration in moderate-severe:
-NO bone involvement: 2-4 weeks
-Osteomyelitis: 4-6 weeks, typically with IV ABXs
-Amputation w/ no residual infection: 2-5 days
Urinary Tract Infections (UTIs): Cystitis
-Lower or upper UTI? Uncomplicated or complicated UTI?
-S/Sx
-Pathogen
-Diagnosis
Lower (bladder and urethra) and uncomplicated UTI
S/Sx: urgency and frequency, nocturia, dysuria, suprapubic tenderness, hematuria
Pathogen: mostly E. coli; others: Proteus, Kelbsiella, Staphylococcus saphrophyticus, enterococci
Diagnosis: urinalysis with pyruira (WBC elevation), bacteria, and positive leukocyte esterase +/- nitrates (E. coli, Proteus, Klebsiella)
-Prescence alone of bacteria does NOT indicate UTI or need for TX
Urinary Tract Infections (UTIs): Cystitis
-TX (DOC, alternatives, pregnancy)
-When is prophylaxis indicated?
TX: usually empiric as outpatient
-DOC: nitrofurantoin (Macrobid) 100mg PO BID x5D (CI if CrCl <60mL/min), Bactrim DS 1 tablet PO BID x3D (avoid in sulfa allergy or >/=20% E.coli resistance rate), or fosfomycin x 1 dose
-Alternatives: beta-lactam (Augmentin or cephalosporin x5-7D, ciprofloxacin x3D, levofloxacin x3D)
-Pregnancy (ALWAYS treat even if asymptomatic): amoxicillin +/- clavulanate, cephalexin; beta-lactam allergy: fosfomycin, Bactrim, nitrofurantoin –> treat for 7 days
**Quinolones: do NOT use in children, pregnancy (cartilage toxicity and arthropathies), those w/ seizures/neuropathy/QT prolongation risk
**Moxifloxacin: do NOT use for UTIs (does NOT reach high enough urine levels)
**Bactrim and nitrofurantoin: only use in pregnancy if other options not available due to potential fetal risk
Prophylaxis: 3 or more episodes in one year –> can use Bactrim SS 1 tablet QD, nitrofurantoin 50mg PO QD, or Bactrim DS 1 tablet after sexual intercourse
Urinary Tract Infections (UTIs): Pyelonephritis
-Lower or upper UTI? Uncomplicated or complicated UTI?
-S/Sx
-Pathogen
-Diagnosis
Upper UTI (kidneys), complicated (men with UTIs automatically is complicated)
S/Sx: flank/costovertebral angle pain, abdominal pain, N/V, fever, chills, malaise +/- cystitis symptoms
Pathogen: E. coli, Proteus, or Klebsiella
-Less common: Enterobacter, Serratia, Pseudomonas, enterococci
Diagnosis: urinalysis with pyruira (WBC elevation), bacteria, and positive leukocyte esterase +/- nitrates (E. coli, Proteus, Klebsiella)
-Prescence alone of bacteria does NOT indicate UTI or need for TX
Urinary Tract Infections (UTIs): Pyelonephritis
-Outpatient TX
-TX (moderately ill vs. severelly ill)
Outpatient TX: ciprofloxacin or levofloxacin or Bactrim
Moderately ill TX:
-If local quinolone resistance >10%: ceftriaxone IV/IM, ertapenem IV/IM, or aminoglycoside extended interval IV/IM then continue with a quinolone as above
-Concern for quinolone AVEs: beta-lactam (Augmentin, cefdinir, cefadroxil, or cefpodoxime) or Bactrim x7-10D
Severely ill TX:
-Initial: ceftriaxone or quinolone (ciprofloxacin or levofloxacin)
-Concern for resistance (prior isolation on culture, urinary instrumentation, recent healthcare exposure, broad spectrum ABXs in past 3 months): piperacillin/tazobactam or carbapenem (if ESBL-producing organism suspected)
-Pseducomonas risk of documented infection: anti-pseudomonal carbapenem
-Last line: cefiderocol, imipenem/cilastin/relebactam, meropenem/vaborbactam, plazomicin
-Step down to PO TX based on culture and susceptiblity
-TX duration for 5-10D based on regimen and clinical response
Phenazopyridine:
-Brand
-ROA
-Administration considerations
-TX
-AVEs
-CIs
Brand: Pyridium (RX), Azo Urinary Pain Relief (OTC)
ROA: PO
Administration:
-Available OTC and RX
-Take with 8oz of water with or immediately following food to minimize stomach upset
-Use for two days maximum
TX: urinary analgesic
AVEs: HA, dizziness, stomach cramps, body secretion discoloration (red-orange of urine or other fluids –> can stain clothing and contact lenses), hemolytic anemia (G6PD deficiency)
CI: renal impairment or liver disease
Clostridium difficle Infection (CDI):
-S/Sx
-Risk factors
-Complications
-Transmission and precaution measures
-Diagnosis
S/Sx: at least three watery stools per day, abdominal cramps, fever, elevated WBCs, impaired renal fxn
Risk factors: healthcare exposure, PPIs, advanced age, immunocrompromised state, obesity, previous CDI, recent ABXs
Complications: inflammation of colon can lead to pseudomembranous colitis which can progress to toxic megacolon
Transmission: fecal-oral
-Precautions: hand hygiene (soap and water), gloves/gown, isolation, ABX stewardship
Diagnosis: positive C. difficle stool toxin or PCR, positive stool test (nucleic acid amplicifaction test =NAAT)
-Nonsevere: WBC <15000 + SCr <1.5
-Severe: WBC >/=15000 + SCr > 1.5
-Fulminant: hypotension, shock, ileus, toxic megacolon
Clostridium difficle Infection (CDI):
-TX in first episode, second episode, and 3rd or subsequent episodes
-TX in fulminant/complicated disease
TX: D/C unecessary ABXs or other possible caustive agents (ex. PPIs)
-First episode: fidaxomicin 200mg PO BID X10D or vancomycin 125mg PO QID x10D (metronidazole only if non-severe and other treatment unavailable)
-Second episode: fidaxomicin 200mg PO BID x10D or vancomycin (prolonged taper acceptable if metronidazole used for initial episode)
-Third or subsequent episodes: fidaxomicin or vancomycin followed by prolonged taper or standard regimen followed by rifaximin 400mg TID x20D or fecal microbiota transplantation
-High risk pts (age >/=65 yo, immunocompromised, severe presentation, and/or hx of CDI in past 6 months): adjunct bezlotuxumab (MAB that binds to toxin B and neutralizes its effects) –> caution in heart failure
Fulminant/complicated disease: vancomycin 500mg PO/NG/PR QID + metronidazole 500mg IV Q8H
-Surgical evaluation for colectomy
Sexually Transmitted Infections (STIs): Syphilis
-Pathogen
-Diagnosis
-Define and discuss TX (DOC, dosing, and alternatives for syphilis (primary, secondary, or early latent; late latent or tertiary; neurosyphilis)
Pathogen: Treponema pallidum (corkscrew-shaped)
Diagnosis: nontreponemal test (VDRL, RPR) + treponemal test (various)
Primary (chancre), secondary (rash, lymphadenopathy), or early latent syphilis (asymptomatic, acquired likely
-Early latent: acquired within past year (asymptomatic)
-DOC: pencillin G benzathine (Bicillin L-A -> do NOT substitute w/ Bicilllin C-R) 2.4 million units IM x1
-Beta-lactam allergy: doxycycline BID x14D, consider densitization if pregnancy, nonadherent w/ TX or unlikely to follow up
Late latent or tertiary syphillis:
-Late latent: acquired >1 year ago or unknown duration, asymptomatic
-Tertiary: CV or CNS manifestations
-TX: same as primary, secondary, or early latent syphilis (except alternative doxycycline for 28 days)
Neurosyphilis (altered mentation, motor/sensory dsysfunction, s/sx of meningitis): can occur at any stage
-DOC: penicillin G aqueous crystalline IV
-Alternatives: penicillin G procaine, densensitization followed by administration of penicilin G aqueous IV in beta-lactam allergy
**For desensitization, confirm allergic rxn with skin test first –> required in neurosphyilis, pregnancy, and expected supotimal adherence to doxycycline
Sexually Transmitted Infections (STIs): Gonorrhea
-Pathogen
-S/Sx
-Diagnosis
-TX (DOC, dose, alternatives)
Pathogen: Neisseria gonorrhoeae
S/Sx:
-Males: urethral discharge, dysuria, or asymptomatic
-Females: commonly asymptomatic –> vaginal pruritus and mucopurulent cervical discharge
Diagnosis: urethral, vaginal, cervical, rectal, and/or pharyngeal swabs
TX:
-DOC: ceftriaxone 500mg IM if pt <150kg (1gm in 150kg or greater)
-If chylamdia has NOT been excluded, add doxycycline
-Alternatives: cefixime PO if ceftriaxone NOT available, gentamicin or azithromycin is cephalosporin allergy
-Pharyngeal infections: ceftriaxone is MOST effective (in severe allergy, consult ID specialist)
Sexually Transmitted Infections (STIs): Chlamydia
-Pathogen
-Diagnosis
-TX (DOC, dosing, alternatives)
Pathogen: Chlamydia trachomatis
Diagnosis: urethral, vaginal, cervical, rectal, and/or pharyngeal swabs
TX:
-DOC: doxycycline 100mg PO BID x7D (if pregnant: azithromycin 1g PO x1)
-Alternatives: erythromycin base PO, levofloxacin PO, or amoxicillin PO in pregnancy
Sexually Transmitted Infections (STIs): Bacterial Vaginosis
-S/Sx
-Pathogen
-TX (DOC, alternatives)
S/Sx: vaginal discharge (clear, white, or gray) that has a “fishy” odor and pH >4.5, little or no pain
Pathogen: many different organisms, including Gardnerella vaginalis
TX:
-DOC: metronidazole x7D OR metronidazole gel x5D OR clindamycin x7D
-Alternatives: clarithromycin PO or ovules OR tinidazole PO OR secnidazole
-Females should NOT douche
Sexually Transmitted Infections (STIs): Trichomoniasis
-S/Sx
-Pathogen
-TX (DOC, alternatives)
S/Sx: yellow/green, frothy vaginal discharge w/ pH >4.5; soreness, pain w/ intercourse
Pathogen: Trichomonas vaginalis
TX:
-DOC: metronidazole x7D (females) or x1 (males)
-Preganncy: metronidazole CI in 1st trimester, but based on additional safety data and AVEs with infections, CDC recommens metronidazole in ALL trimesters
Sexually Transmitted Infections (STIs): Genital Warts
-Pathogen
-S/Sx
-TX
-Prevention
Pathogen: Human papillomavirus (HPV) strains 6 & 11
S/Sx: single or multiple pink or skin-colored lesions that range from smooth, flattened papules to cauliflower-like growths
TX:
-DOC: imiquimod cream
-TX NOT required if asymptomatic (warts generally resolve spontaneously within one year)
-Imiquimod can weaken condoms and diaphragms and irritate anogenital mucosa (abstain from sexual activity while cream is on skin)
Prevention: Gardasil vaccine
Common Tickbone Diseases: pathogens, s/sx, and TX for Rocky Mountain Spotted Fever
-Pathogen: Rickettsia rickettsii
-Can be fatal (s/sx: muscle pain, HA, fever then followed 3-5 days later by erythematous petechial rash - red spots caused by bleeding into the dermis)
-TX: doxycycline PO/IV x5-7D (DOC including in pediatric pts
Common Tickbone Diseases: pathogens, s/sx, and TX for Lyme Disease
-Pathogen: Borrelia burgodorferi, Borrelia mayonii
-S/Sx: early (<1 month) erythema migrains and flu-like syndrome, late: disseminated disease and organ dysfunction or chronic disorders (arthritis)
-TX: doxycycline BID x10D OR amoxicillin PO x14D OR cefuroxime PO x14D
-Severe: IV ceftriaxone
Common Tickbone Diseases: pathogens, s/sx, and TX for Ehrlichiosis
-Pathogen: Ehrlichia chaffeensis
-S/Sx: round, “bull’s eye”, rash (uncommon), confusion
-TX: doxycycline PO/IV BID x7-14D
