Empiric Antibiotic Management for Major Infections at MSKCC
September 18, 2013
Anna Kaltsas MD MS
Assistant Attending Physician
Infectious Diseases Service
Green team: attending only
◦ Solid tumors, Ortho, GU,
Blue team: attendings + ID
◦ Leukemia, lymphoma, ICU,
Pharmacists – Antibiotic
Approval bpr 1100
Infection control – x7814
MSKCC guidelines on
intranet (“Reference manuals
Draw blood cultures first!!!
◦ Don’t forget UA, urine culture, CXR, C. difficile, LP if
◦ Work up for other source: ultrasound r/o DVT
◦ Not all fevers need empiric antibiotics!
Consider contact/respiratory isolation needs
Previous culture results
What types of bacteria?
◦ Anatomic site
Oral/GI: mixed, anaerobes
Skin: GPC, ?viral
Lung: atypical, GPC;
HAP: GNR, anaerobes (aspiration)
◦ Most commonly reported
medication allergy – 10% of all
◦ Anaphylaxis: 1-4 episodes/10,000
◦ 85-90% found not to be truly
allergic (IgE mediated)
History of PCN “allergy”: only 0.17-
8.4% will react to cephalosporins
PCN allergy by skin test: 2% will react
Imipenem: 0-11% cross reactive
Aztreonam, quinolones: 0 cross
Vancomycin/red man syndrome:
◦ histamine-mediated; rate
dependent infusion reaction.
◦ Not a true allergy!
annually/80,000 in ICU
High hospital cost, patient
morbidity, 12-25% mortality
Suspect if tunnel/exit site
erythematous, has discharge,
or pt has fever without a
CVC + PICC > tunneled
catheters and implanted ports
Sources for infection:
◦ Skin flora (extraluminal)
◦ Contamination from hubs/access
◦ Hematogenous/Infusion related
Gram stain with GPC: Vancomycin
◦ Recent history of VRE: Linezolid
Gram stain with GNR: Zosyn or Cefepime
◦ Narrow to cephalosporin or oral quinolone when sensitivities are
back and repeat cultures are negative.
MSSA: oxacillin, nafcillin, cefazolin superior to
◦ Pull line
◦ Optho consult (rule out endophthalmitis), TEE
Repeat blood cultures daily until negative x72 hours.
◦ If repeated cultures positive after 72 hours of appropriate
antibiotics, consider pulling line.
◦ If patient is sick/septic, consider pulling line.
Ok to replace central line/PICC when blood cultures clear
O’Grady NP et al. Guidelines for the
prevention of intravascular catheter-
related infections. CID 2011:52.
Mermel LA et al. Clinical practice
guidelines for the diagnosis and
management of intravascular catheter-
related infections: 2009 update by the
Infectious Diseases Society of
America. CID 2009:49
Skin flora are common
C. jeikeium, Bacillus, diptheroids
(gram positive bacilli)
Suspect contamination if single
culture from one lumen positive.
◦ All peripheral cx and other lumens
◦ Pt/catheter looks well and has other
source for fever.
◦ Blood cx were drawn before
S. aureus and Candida spp are
almost never contaminants!
Scanning EM; Bacteria
underneath human toenail.
UTI = most common nosocomial infection.
◦ 10-30% of catheterized patients develop bacteriuria.
10-25% of those with bacteriuria develop UTIs
Up to 80% of patients with cutaneous diversion of
urine through conduits develop bacteriuria and
◦ Stomal mucus, nephrostomy tubes, stents, catheters allow
for biofilm formation and propagation of bacterial growth.
◦ UTI/pyelonephritis can occur from stasis of urine, reflux of
urine, self catheterization techniques.
◦ PCN/stent obstruction or dislodgement:
Temporary blockage of the flow of (colonized urine) can result
in ascending infection, fever, bacteremia.
Symptoms: fever >38oC, suprapubic/CVA tenderness, SIRS
Diagnosis: urine cx >105 cfu/mL OR urine cx >103 cfu/mL with
pyuria on UA + above symptoms – on repeat specimen AFTER
Warren J. Catheter-associated urinary tract infections.
Infect Dis Clin; 1997. 11(3):609-22.
Bruce AW et al. Bacterial adherence in the human ileal
conduit: a morphological and bacteriological study. J Urol.
UAs are unreliable in patients with
foley catheters, PCNs, ileal conduits.
◦ Change foley and repeat UA/urine culture
Ceftazidime, Cefepime, Zosyn
◦ Narrow once antibiotic sensitivities are
◦ Target initial antibiotics to past urine
◦ High rate of GNR resistance to quinolones!
Enterococcus, CN staph, Candida are
often contaminants (perineal flora,
colonization of catheters).
Asymptomatic bacteriuria does not
have to be treated except in
pregnancy or before GU procedures.
In patients with GU hardware –
persistent fever/UTI sx despite
appropriate antibiotics is an indication
to replace stent/PCN!
8-15 cases/1,000 persons per year
Highest in winter months,
extremes of age
S. pneumoniae most common
Suspect if: cough (productive),
fever, pleuritic chest pain, dyspnea
Following viral illness
High risk: >65, smokers, recent
chemo, neutropenia, intubated,
Post-obstructive PNA: lung
mass/met obstructing bronchus
◦ head and neck surgery
◦ speech/swallowing difficulties
◦ mental status changes
◦ Tube feeds/aspiration event! Right middle lobe pneumonia.
Does the patient need
respiratory isolation (viral,
◦ Chest Xray/CT Chest (non
◦ Sputum cultures/deep tracheal
cultures if intubated
◦ Blood cultures
◦ If CAP: Legionella urine antigen,
S. pneumoniae urine antigen
◦ Viral nasal swab (automatic
◦ To rule out TB: sputum for AFB
x2, 24 hours apart
Gram positive diplococci on sputum gram stain.
Inpatient, non ICU, CAP:
◦ Ceftriaxone 1gm IV daily x7d + Azithromycin 500
mg IV/po daily x5d
◦ Unasyn or Ceftriaxone + Flagyl
ICU, Hospital-acquired PNA, nursing home
◦ Zosyn 4.5 gm IV Q6h + Cefepime 2 gm IV Q12h
+/- Azithromycin 500 mg IV daily +/- Vancomycin
IV x5-7 days
◦ PCN allergy: Aztreonam + Flagyl; Imipenem
Infection extending beyond the
hollow viscus into previously
sterile peritoneal space.
◦ Cholecystitis, diverticulitis, bowel
>1000 species of gut bacteria;
more than 10 times the number
of cells in the human body!
◦ Abscess formation
Second most common cause of
infectious mortality in ICUs.
Appendicitis alone: 300,000
Solomkin et al. Diagnosis and Management of Complicated
Intraabdominal Infections in Adults and Children: Guidelines by the
Surgical Infection Society and the Infectious Disease Society of
America. CID 2010:50
Diagnosis: Physical exam, CT scan (po and IV contrast),
ultrasound (gall bladder).
◦ Signs of sepsis may be minimal in elderly or those on high-dose
Draw blood cultures
Start appropriate antibiotics
◦ Cover GI flora: GNR, anaerobes, enterococcus, +/- Pseudomonas,
◦ Cover organisms previously isolated in abscess drainages
◦ Culturing fluid in JP drains is low yield
Surgical or IR consult
◦ Mainstay of treatment for intra-abdominal abscess is surgical
drainage + antibiotics!
◦ Biliary stent change
◦ Treat for 10-14 days post drainage or until abscess resolved on
follow up imaging.
Unasyn, Zosyn, and Imipenem have anaerobic
Spontaneous Bacterial Peritonitis
◦ Ceftriaxone 2gm IV daily
Bowel Perforation, Intraperitoneal abscess
◦ Include Pseudomonas coverage!
◦ Zosyn or Cefepime/Flagyl OR Cipro/Flagyl +/- Vancomycin
◦ Unasyn Or Cipro/Flagyl
Neutropenic Enterocolitis (Typhlitis)
◦ Include Pseudomonas coverage!
◦ Zosyn + Amikacin
Gall bladder (biliary sepsis, cholangitis, cholecystitis)
◦ Unasyn OR Ceftriaxone/Flagyl OR Ciprofloxacin/Flagyl
Gram positive anaerobic
bacillus; toxin producing.
Most common cause of
antibiotic-associated diarrhea in
◦ Diarrhea; colitis; toxic megacolon;
20-30% recurrence rate; 1-2.5%
overall mortality; 25% mortality
in elderly or very infirm.
Cepheid GeneXpert PCR
Do not use as “test of cure” –
Initial episode, mild/moderate:
WBC <15, Cr <1.5:
◦ Flagyl 500 mg po Q8h
Initial episode, moderate or
severe, sepsis: WBC >15, Cr
◦ Vancomycin 125 mg po Q6h
Unable to take po, ileus, toxic
Flagyl 500 mg IV Q8h + Vancomycin
Same as initial therapy x14 days
Third or more episodes:
◦ Consider ID consult; prolonged
Vancomycin po taper
Commonly seen at MSK
Risk factors include
LND – upper extremity
lymphedema; pelvic LND – lower
extremities), diabetes, PVD,
DVTs, chemotherapy, radiation
Beware venous stasis dermatitis!
Abscesses require I&D
Culture anything that’s draining
Blood cultures low yield unless
Antibiotics: Ancef 1gm IV q8h
◦ Vancomycin if PCN allergic or high
suspicion for MRSA
◦ Skin flora: Keflex, Cefadroxil
◦ MRSA: Clindamycin, Doxycycline,
Cellulitis in setting of
Left leg cellulitis
Women with lymphedema have
10 times the risk of cellulitis
(Brewer et al, Risk factor analysis for breast cellulitis complicating breast
conservation therapy; Clin Infect Dis. (2000) 31 (3): 654-659.)
Skin flora, ?gram
negatives in seromas
Ancef -> po Cefadroxil
Vancomycin if PCN allergic
quinolone for gram
negative coverage if no
improvement, evidence for
Repeated infections or
history of S. aureus: may
need to remove
Cellulitis with tissue expander.
“flesh eating disease;” can spread
through tissue at a rate of 3
Needs IMMEDIATE surgical
Polymicrobial; Group A strep
Bacteria introduced by minor
◦ Minor erythema, “pain out of
proportion to exam”
◦ Deep tissue infection, sepsis, shock
Fournier’s gangrene: NF of pelvic
ABX: Unasyn or Zosyn +
Vancomycin +/- Clindamycin
Mortality 8-10% per episode
◦ Higher with liquid tumors, advanced age, multiple co-
◦ Higher mortality: Gram negative bacteremia > gram
“GI” or “oral” source – mucositis, translocation of
bacteria across mucosa
Invasive fungal infections with prolonged neutropenia
Work up: Physical exam, CBC, chemistry, CXR or CT
Chest, blood cultures x2, UA/urine culture
◦ Zosyn or Cefepime; OR Aztreonam + Vancomycin
◦ After 72 hours: add Vancomycin
◦ After 5-7 days add Ambisome
◦ Await count recovery!!
Kuderer et al. Mortality, morbidity, and
cost associated with febrile
neutropenia in adult cancer patients.
Cancer; 2006. 106(10):2258.