Antibiotic Essentials

Created January 2016

Information contained was compiled using
Wesley Healthcare 2015 susceptibility data.
Full antibiogram available electronically on the Wesley Intranet.
For a printed copy of the antibiogram, please contact the pharmacy.

Contacts
Main Pharmacy 962-2305
Infectious Diseases Pharmacist 962-7474
Stephanie Kuhn, PharmD, BCPS

Infection Prevention 962-7570

Microbiology Lab 962-2880

Microbiology Lab Director 962-2984
Kathy Beadle, MT (ASCP)

Infectious Diseases Physician

Thomas Moore, MD 962-3030
 Clinical Pearls
Asymptomatic bacteriuria  Positive urine cultures (even if >100,000 cfu) without
presence of symptoms do not require antibiotic treatment
unless the patient is pregnant or undergoing urinary surgery
 Document as bacteriuria
Urinary tract infections  31% of Proteus mirabilis and 28% of E. coli strains are
resistant to ciprofloxacin
 Consider using an alternative agent (such as ceftriaxone) for
empiric therapy
Skin and soft tissue infections  Clindamycin combination therapy is only indicated in
Group A Streptococcus infections
 Purulent infection, moderate to severe: consider MRSA
coverage with vancomycin
 Non-purulent or diffuse infections, mild to moderate:
β-lactam (cefazolin) is preferred. Consider clindamycin as an
allergic alternative
Methicillin-susceptible  Cefazolin (IV) or cephalexin (PO) are the drugs of choice
Staphylococcus aureus (MSSA)  Nafcillin continuous infusion is an alternative
 54% of staphylococcus aureus isolates are oxacillin sensitive
(MSSA)
Enteroccocal infections  Ampicillin (IV) or amoxicillin (PO) are the drugs of choice,
unless resistant
 Adding a β-lactamase inhibitor (ampicillin/sulbactam or
amoxicillin/clavulanate) does not add any benefit, as this is
not the resistance mechanism of Enterococcus
 Cephalosporins do not cover Enterococcus
Extended-spectrum beta-  Meropenem is the preferred drug for ESBLs
lactamase producers (ESBLs)  6% of E. coli and 3% of Klebsiella pneumoniae are ESBLs
Haemophilus influenza and  32% of H. influenzae and 73% of M. catarrhalis are
Moraxella catarrhalis β-lactamase producing
 Preferred therapy includes:
IV: ampicillin/sulbactam or ceftriaxone
PO: amoxicillin/clavulanate or cefuroxime
Candida infections  78% of Candida isolated from all sites is C. albicans
 72% of Candida isolated in the blood is C. albicans
 Fluconazole is the drug of choice for C. albicans
 Consider fluconazole empirically, unless the patient is
critically ill or has a history of recent azole exposure
 Micafungin is the echinocandin on formulary
De-escalation Tips
 Consider evaluating the patient at 48 hours (at a minimum) to determine if antibiotics can be
de-escalated
 De-escalation can occur both when specific organisms have been isolated or when no specific
organism has been isolated
 When narrowing based on reported sensitivities, do not compare MIC values. MIC values are
organism and drug specific. A lower MIC does not necessarily mean a better agent.
 Consider the following additional tips:
If Then
Viral panel is positive STOP antibiotics
S. aureus is not isolated DC vancomycin
Resistant gram-negative organisms are not De-escalate from piperacillin/tazobactam or
isolated (e.g. Pseudomonas, Enterobacter) cefepime to ampicillin/sulbactam or ceftriaxone
No isolate is identified or normal flora is identified De-escalate to an oral antibiotic if patient is
clinically stable to do so
st
Isolate is susceptible to a 1 generation Do not use a 3rd generation cephalosporin (e.g
cephalosporin ceftriaxone), de-escalate to the narrowest
spectrum (e.g. cefazolin)

IV antibiotic Oral equivalent

Ampicillin Amoxicillin
Ampicillin/Sulbactam Amoxicillin/clavulanate
Ceftriaxone Cefdinir
Cefazolin Cephalexin

C. difficile colitis risk and antibiotic selection

Antibiotic Risk Ratio
Penicillin 1.9
Clindamycin 1.9
Beta-lactamase combinations 2.3
st nd
1 and 2 generation cephalosporins 2.4
3rd and 4th generation cephalosporins 3.1
Fluoroquinolones 4
C. difficile risk increases with antibiotic days*
4-7 days=40% 8-18 days=300% >18 days=780%
*1 day=1 day per drug (1 day of triple-drug therapy= 3 antibiotic days)
Stevens V, et al. Clin Infect Dis. 2011; 53:42-48
 Preferred Antimicrobial List for Selected Disease States in Adults
Please Note: This table is only a guide, designed to assist healthcare providers in selecting an appropriate, empiric antimicrobial
regimen and may or may not be appropriate for all patients. Ultimately, the antibiotic course depends upon culture results and the
patient’s clinical course.
For additional information, please see order sets or contact the pharmacy at 962-2305
*All dosing assumes IBW and normal renal and hepatic function
Disease State Common Pathogens Adult Empiric Therapy* Duration of Therapy
Non- ICU:
Ceftriaxone 1 gm IV Q24 hours
H. influenzae Non-ICU:
+
S. pneumoniae 5 days
Doxycycline 100 mg PO Q12 hours x7 days or
Azithromycin PO 500 mg daily x 3 days
Plus atypicals ICU:
OR
Community including 7 days
Levofloxacin 750 mg PO Q24 hours x 5 days
Acquired (CAP)
(for cephalosporin allergy)
M. Specific pathogens may
ICU:
pneumoniae require longer therapy, e.g.
Ceftriaxone 1 gm IV Q24 hours
C. pneumoniae 14 days if Pseudomonas is
+
isolated
Azithromycin IV 500 mg daily x 3 days or
Levofloxacin 750 mg IV Q24 hours x 5 days
1-2 Ampicillin/Sulbactam 3 gm IV Q6 hours
Pneumonia
OR
Pathogens Clindamycin 300 mg PO/IV Q6 hours
Aspiration including + 5 days
Anaerobes Ceftriaxone 1 gm IV Q24 hours or
Levofloxacin 750 mg PO Q24 hours (if
cephalosporin allergy)
Cefepime 1 gm IV Q6 hours or
Piperacillin/Tazobactam IV 3.75 gm
HAP/HCAP/ P. aeruginosa over 4 hrs Q8 hrs
7 days
VAP K. pneumoniae +
or Risk of Acinetobacter Vancomycin (20-25 mg/kg load plus pharmacy to
Specific pathogens may
Pseudomonas S. aureus dose)
require longer therapy
or MRSA (MRSA) +/-
Tobramycin 7 mg/kg IV Q24 hours or
Ciprofloxacin 400 mg IV Q8 hours
Ceftriaxone 2 gm IV Q12 hours +
S. pneumoniae
Age <50 yrs Vancomycin (20-25 mg/kg load plus
N.meningitides
3 pharmacy to dose)
Meningitis Patient and pathogen
Ceftriaxone 2gm IV Q12 hours +
S. pneumoniae dependent
Vancomycin (20-25 mg/kg load plus
Age >50 yrs N.meningitides
pharmacy to dose) +
Listeria
Ampicillin 8 gm continuous infusion Q24 hours
Cefazolin 1-2 gm IV Q8 hours OR
β-hemolytic Nafcillin 8 gm continuous infusion Q24 hours OR
Erysipelas Uncomplicated: 5 days
streptococcus Penicillin G 18 million units continuous infusion
Cellulitis/
4 Q24 hours
Erysipelas Abscess/Complicated:
Purulent/
Vancomycin (20-25 mg/kg load plus pharmacy to 7-10 days
abscess or Risk S. aureus
dose)
of MRSA
References: 1IDSA/ATS guidelines on CAP in adults. CID 2007; 44: S27-72. 2ATS, IDSA. Guidelines for adults with HAP, VAP, HCAP pneumonia. Am J Respir Crit Care Med 2005; 171: 388-416. 3Guidelines for
bacterial meningitis. CID 2004; 39: 1267-84. 4Guidelines SST infections. CID 2005; 41: 1373-406. 5Diagnosis and treatment of diabetic foot infections. CID 2012; 54: e132-73. 6Intra-abdominal infection
guidelines. CID 2010; 50: 133-164. 7Trial of Short-Course Antimicrobial Therapy for Intraabdominal Infection. NEJM 2015; 372:1996-2005. 8IDSA/SHEA C difficile Guidelines. ICHE 2010; 31:431-55.
9
Guidelines for uncomplicated acute bacterial cystitis and acute pyelonephritis in women. CID 2011; 52:e103-2. 10Antimicrobial prophylaxis in surgery. AJHP. 2013; 70:195-283.
 Preferred Antimicrobial List for Selected Disease States in Adults (continued)
Please Note: This table is only a guide, designed to assist healthcare providers in selecting an appropriate, empiric antimicrobial
regimen and may or may not be appropriate for all patients. Ultimately, the antibiotic course depends upon culture results and the
patient’s clinical course.
For additional information, please see order sets or contact the pharmacy at 962-2305
*All dosing assumes IBW and normal renal and hepatic function
Disease State Common Pathogens Adult Empiric Therapy* Duration of Therapy
Ampicillin/Sulbactam 3 gm IV Q6 hours or
Polymicrobial: Piperacillin/Tazobactam IV 3.75 gm
β-hemolytic Strep over 4 hrs Q8 hrs
Diabetic Foot S. aureus if Pseudomonas concern Patient and pathogen
5
Infections Pseudomonas +/- dependent
Gram-negative rods Vancomycin (20-25 mg/kg load plus pharmacy to
Anaerobes dose)
if MRSA concern
Enterococcus
Intra- Abscess E. coli After Source Control: 4 days
Ceftriaxone 1 gm IV Q24 hours +
abdominal Cholecystitis Entero- Abscess: Varies based on
6,7 Metronidazole 500 mg PO Q12 hours
Infections Diverticulitis bactericeae patient response
Anaerobes

Mild to Moderate Metronidazole 500 mg PO Q8 hours Usual 14 days

For patients on Antibiotics:
Severe Vancomycin PO 125 mg PO Q6 hours Treat 4+ days after antibiotic
8 discontinuation
C difficile
Severe Complicated:
S/S of ileus, toxic megacolon, Metronidazole 500 mg IV Q8 hours +
Treat at least 14 days
perforation, sepsis related to Vancomycin 500 mg via retention enema Q6 hours
C. difficile
Cephalexin 500 mg PO Q6 hours OR
Uncomplicated: 3 days
Cystitis Amoxicillin 500 mg PO Q8 hours
E. coli Complicated: 7-10 days
Urinary Tract (if Enterococcus concern)
9 Proteus Complicated with structural
Infections Ceftriaxone 1 gm IV Q24 hours OR
Klebsiella abnormalities or
Ampicillin 8 gm continuous infusion Q24 hours
Pyelonephritis Enterococcus pyelonephritis:
(if Enterococcus concern) OR
10-14 days
Ciprofloxacin 500 mg PO Q12 hours
Pre-operative Please refer to order set #347 for recommendations based on specific surgical type
Surgical No antibiotic prophylaxis is necessary to be continued post-op.
10
Prophylaxis Post-operative If it is clinically necessary to continue antibiotics for prophylaxis do not exceed
24 hours post-op and 48 hours for cardiac surgeries.
References: 1IDSA/ATS guidelines on CAP in adults. CID 2007; 44: S27-72. 2ATS, IDSA. Guidelines for adults with HAP, VAP, HCAP pneumonia. Am J Respir Crit Care Med 2005; 171: 388-416. 3Guidelines for
bacterial meningitis. CID 2004; 39: 1267-84. 4Guidelines SST infections. CID 2005; 41: 1373-406. 5Diagnosis and treatment of diabetic foot infections. CID 2012; 54: e132-73. 6Intra-abdominal infection
guidelines. CID 2010; 50: 133-164. 7Trial of Short-Course Antimicrobial Therapy for Intraabdominal Infection. NEJM 2015; 372:1996-2005. 8IDSA/SHEA C difficile Guidelines. ICHE 2010; 31:431-55.
9
Guidelines for uncomplicated acute bacterial cystitis and acute pyelonephritis in women. CID 2011; 52:e103-2. 10Antimicrobial prophylaxis in surgery. AJHP. 2013; 70:195-283.
 Preferred Antimicrobial List for Selected Disease States in Pediatrics
Please Note: This table is only a guide, designed to assist healthcare providers in selecting an appropriate, empiric antimicrobial regimen and may or may not be
appropriate for all patients. Ultimately, the antibiotic course depends upon culture results and the patient’s clinical course.
For additional information, please see order sets or contact the pharmacy at 962-2305 *All dosing assumes normal renal and hepatic function
Disease State Common Pathogens Pediatric Empiric Therapy Duration of Therapy
Simple, Untreated, Immunized:
Ampicillin 75 mg/kg (max dose of 2000 mg) IV Q6 hours
H. influenzae
Failed treatment or Complication:
S. pneumoniae 7-10 days
Ceftriaxone 50 mg/kg (max dose of 1000 mg) IV Q24 hours
Plus atypicals Shorter courses may be
Community Optional Additional Coverage:
including just as effective, specific
Acquired (CAP)
pathogens may require
Concern for Atypical Pathogens:
M. pneumonia longer therapy
Azithromycin I0 mg/kg (max dose of 500 mg) PO ONCE, then 5mg/kg
C. trachomatis
(max dose of 250 mg) PO daily AC breakfast x 4 doses
C. pneumoniae
1-2 Concern for S. aureus:
Pneumonia Vancomycin 20 mg/kg IV Q6 hours
Piperacillin/tazobactam
Dosed based off piperacillin component
Age <30 days: 75 mg/kg IV Q6 hours (over 30 min)
Age ≥30 days: 100 mg/kg (max 3000 mg) Q8 hours (over 4 hours)
OR
K. pneumoniae 7 days
VAP, Risk of Cefepime 50 mg/kg (max 1000 mg) IV Q8 hours
Acinetobacter
Pseudomonas +
P. aeruginosa Specific pathogens may
or MRSA Vancomycin 20 mg/kg (max 1000 mg) IV Q6 hours
S. aureus (MRSA) require longer therapy
±
Tobramycin
Age <1 month: 4 mg/kg Q24 IV hours
Age 1-6 months: 6 mg/kg Q24 IV hours
Age >6 months: 7.5 mg/kg Q24 IV hours
S. agalactiae
Ampicillin 75 mg/kg IV Q6 hours +
Age <1 month E. coli
Cefotaxime 50 mg/kg IV Q6 hours
Listeria
3 S. pneumoniae Patient and pathogen
Meningitis Age 1 month to Ceftriaxone 50 mg/kg (max dose of 2000 mg) IV Q12 hours +
N. meningitides dependent
<12 yrs Vancomycin 20 mg/kg IV Q6 hours
H. Influenzae
N. meningitides Ceftriaxone 50 mg/kg (max dose of 2000 mg) IV Q12 hours +
Age ≥12 yrs
S. pneumoniae Vancomycin 20 mg/kg (max dose of 1500 mg) IV Q6 hours
β-hemolytic Cefazolin 30 mg/kg IV Q8 hours OR Uncomplicated:
Erysipelas
streptococcus Nafcillin 200 mg/kg/day Q24 hours as a continuous infusion 5 days
Cellulitis/
4 Purulent/
Erysipelas abscess or Risk S. aureus Vancomycin 20 mg/kg IV Q6 hours Abscess/Complicated:
of MRSA 7-10 days
Piperacillin/tazobactam
Dosed based off piperacillin component After Source Control:
Enterococcus
Intra-abdominal Abscess Age <30 days: 75 mg/kg IV Q6 hours (over 30 min) 4 days
E. coli
5,6 Cholecystitis Age ≥30 days: 100 mg/kg (max 3000 mg) IV Q8 hours (over 4 hours)
Infections Diverticulitis
Enterobactericeae
OR Abscess: Varies based on
Anaerobes
Ceftriaxone 50 mg/kg IV Q24 hours + patient response
Metronidazole 10 mg/kg PO Q8 hours

E. coli Cephalexin 50 mg/kg/day PO in 2-3 divided doses

Urinary Tract
7 Proteus OR 7-14 days
Infections Klebsiella Ceftriaxone 50 mg/kg IV Q24 hours

Continue until neutropenia

S. epidermidis subsides
Cefepime 50 mg/kg (max 2000 mg) IV Q8 hours
K. pneumonia (ANC ≥ 500 cells/mm3) and
Neutropenic ±
8 P. aeruginosa afebrile or longer
Fever Vancomycin 20 mg/kg (max dose of 1000 mg) IV Q6
S. aureus if clinically necessary
E. coli depending on
symptoms and pathogen.
References: 1IDSA guidelines on CAP in infants and children. CID 2011; e1-52. 2Sandora TJ, Harper MB. Pneumonia in hospitalized children. Pediatr Clin North Am 2005; 52:1059. 3Guidelines for bacterial
meningitis. CID 2004; 39: 1267-84. 4Guidelines SST infections. CID 2005; 41: 1373-406. 5Intra-abdominal infection guidelines. CID 2010; 50: 133-164. 6Trial of Short-Course Antimicrobial Therapy for
Intraabdominal Infection. NEJM 2015; 372:1996-2005 7Guidelines for uncomplicated acute bacterial cystitis and acute pyelonephritis in women. CID 2011; 52:e103-2. 10Antimicrobial prophylaxis in surgery.
AJHP. 2013; 70:195-283. 8IDSA guidelines on Anitmicrobial agent in Neutropenic Patients. CID 2011; e56-93.