Antibiotic update in icu

94
Sherif Anis, MD Assistant professor of Anesthesia & ICU Ain Shams University

Transcript of Antibiotic update in icu

Page 1: Antibiotic update in icu

Sherif Anis, MD

Assistant professor of Anesthesia & ICU

Ain Shams University

Page 2: Antibiotic update in icu

Objectives Identify the appropriate 1st and 2nd line antibiotic for

empiric treatment of common bacterial infections in the community and hospital settings

Tailor the choice of antibiotic based on unique patient risk factors

Reducing bacterial resistance

Identify resources for information on safe, effective treatment

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Conventional antibiotics Penicillins

Cephalosporins

Carbapenems

Quinolones

Aminoglycosides

Macrolides

Tetracyclines

Nitrofurantoin, metronidazole, clindamycin, vancomycin, teicoplanin, cotrimoxazole, fusidic acid, etc

Isoniazid, pyrazinamide, ethambutol, rifampin, cycloserine, etc

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Penicillins Penicillin G

Still useful for a number of diseases (e.g. meningitis, syphilis)

Cloxacillin For MSSA infections

Ampicillin, amoxicillin Active vs. Gram-positive (not MSSA), Gram-negative organisms

Augmentin, Unasyn Broad spectrum, covers Gram-positive, Gram-negative and

anaerobes

Piperacillin, Tazocin, Timentin Are active vs. Pseudomonas

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Cephalosporins Cefazolin, cephalexin

Active vs. Gram-positive organisms including MSSA

Cefuroxime, Cefaclor Covers some Gram-negative organisms

Cefotaxime, Ceftriaxone Broad spectrum, enhanced activity towards Gram-

negative organisms

Ceftazidime, Cefepime, Sulperazon Additive Pseudomonas coverage

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Carbapenems Imipenem

Broad spectrum, covers Gram-positive, Gram-negative (including ESBL-producing strains), Pseudomonas and anaerobes

Meropenem Less seizure-inducing potential, can be used to treat

CNS infections

Ertapenem Lacks activity vs. Acinetobacter and Pseudomonas

Has limited activity against penicillin-resistant pneumococci

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Quinolones Ciprofloxacin

Active vs. MSSA, Gram-negative and Pseudomonas

Levofloxacin

Has activity vs. Streptococcus pneumoniae, but slightly less active towards Pseudomonas compared to ciprofloxacin

Moxifloxacin

Has activity vs. anaerobes but less active towards Pseudomonas

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Aminoglycosides Active vs. some Gram-positive and Gram-negative

organisms

Gentamicin Active vs. Pseudomonas

Tobramycin More active vs. Pseudomonas than gentamicin

Shows less activity against certain other Gram-negative bacteria

Amikacin More stable to enzymes, used in severe infections by gentamicin-

resistant organisms

Streptomycin Used for tuberculosis

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Macrolides Erythromycin

Active vs. Gram-positive organisms, atypicals

GI side effects

Clarithromycin

Slightly greater activity than erythromycin

Azithromycin

Slightly less active than erythromycin vs. Gram-positive but enhanced activity vs. some Gram-negative organisms

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Tetracyclines Drug of choice in infections caused by Chlamydia,

Rickettsia, Brucella and Lyme disease Value has decreased due to increasing bacterial

resistance Tetracycline

Role in Helicobacter pylori eradication (less frequently used than other antibiotics)

Doxycycline Once daily

Minocycline Broader spectrum

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Other antibiotics Clindamycin

Vs. Gram-positive cocci and anaerobes

Metronidazole

Vs. anaerobes

Preferred therapy in antibiotic associated diarrhoea (Clostridium difficile) than oral vancomycin, although unlicenced

Vancomycin, teicoplanin

For Gram-positive organisms (including MRSA)

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Other antibiotics Cotrimoxazole

Role in uncomplicated UTI, UTI prophylaxis, acute exacerbations of chronic bronchitis

Pneumocystis carinii (now jiroveci) infections

Nitrofurantoin For UTI, prophylaxis vs. UTI

Fusidic acid, rifampin For penicillin-resistant staphylococci

Not for monotherapy due to risk of emergence of resistance

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Classes Bacteriostatic vs Bactericidal

Narrow vs Broad spectrum

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Classes Bacteriostatic

Aminoglycosides (Streptomycin, Amikacin,

Gentamicin, Tobramycin)

Lincosamides (Clindamycin)

Macrolides (Azithromycin)

Tetracyclines (Doxycycline)

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Bactericidal Aminoglycosides

Glycopeptides (Vancomycin)

Lipopeptides(Daptomycin)

Nitrofurans

Metronidazole

Penicillins

Cephalosporins

Monobactams(Aztreonam)

Carbapenems(Meropenem)

Quinolones

Sulfonamides

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Broad Spectrum Amoxicillin/clavulanate (Augmentin)

Ampicillin/sulbactam (Unasyn)

Piperacillin/tazobactam (Tazocin)

Ticarcillin/clavulanate (Timentin)

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Newer Classes Cyclic lipopeptides (daptomycin)

Bactericidal against Gram-positive, including MRSA

Glycylcyclines (tigecycline)

Bacteriostatic against Gram-pos, Gram-neg and MRSA

Oxazolidinones (linezolid) Bacteriostatic and bactericidal against Gram-positive, including

MRSA, VRE

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Good news vs. bad news Good news

A few novel antibiotics have shown promising results / are undergoing clinical studies

Bad news As immunosuppressive diseases and use of immunosuppressive

agents become more prevalent, opportunistic infections becomes more common, esp. by organisms rarely encountered previously Diseases: e.g. HIV, leukemia

Drugs: e.g. in solid organ transplants, bone marrow transplants, rheumatoid disorders

Development of bacterial resistance to antibiotics is much faster than research and development of new antibiotics

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Principles on choosing an antibiotic for empiric therapy As best possible, attempt to localize the site of

infection

Do a good exam!!!

Occam’s razor

“Plurality must not be posited without necessity”

Use only one diagnosis whenever possible

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Gram-positive superbugsResistant Gram-positive bacteria terminology

PRSP Penicillin resistant Streptococcus pneumoniae

MDRSP Multidrug resistant Streptococcus pneumoniae

MRSA Methicillin resistant Staphylococcus aureus

VRSA Vancomycin resistant Staphylococcus aureus

VISA (GISA) Vancomycin (Glycopeptide) intermediate

Staphylococcus aureus

VRE (GRE) Vancomycin (Glycopeptide) resistant Enterococcus

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Case 1 F/74, DM on oral hypoglycemic drugs

Presented with fever and malaise, cough with sputum, tachypnea; chest X-ray revealed bilateral infiltrates

Travel history, occupation, contact and clustering non-remarkable

Received a course of amoxicillin for urinary tract infection 10 weeks ago

Diagnosis: Community-acquired pneumonia

Question What is the empirical treatment for CAP?

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Chest X-ray

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Chest X-ray

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Community-acquired pneumonia (CAP) Microbiology

“Typical” organisms Streptococcus pneumoniae Haemophilus influenzae Moraxella catarrhalis

“Atypical” organisms Chlamydia pneumoniae Mycoplasma pneumoniae Legionella pneumophilia

Empirical therapy Beta-lactams to cover typical organisms Doxycycline / macrolides to cover atypical organisms Respiratory fluoroquinolones (levo, moxi) for beta-lactam allergy

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Community-acquired pneumonia (CAP) Empirical therapy

CAP, out-patient Augmentin/Unasyn PO ±macrolide PO

Amoxicillin PO + clarithromycin / azithromycin PO

CAP, hospitalized in general ward Augmentin / Unasyn IV/PO ±macrolide

Cefotaxime / ceftriaxone IV ±macrolide

CAP, hospitalized in ICU for serious disease Add cover to Gram-negative enterics

Tazocin / cefotaxime / ceftriaxone IV + macrolide

Cefepime IV + macrolide

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Community-acquired pneumonia (CAP) Empirical therapy

Modifying factors Allergy to beta-lactams

Fluoroquinolone (levofloxacin / moxifloxacin)

Aspiration likely: anaerobes should be covered

Augmentin / Unasyn / Tazocin already provide coverage

Cephalosporins (except Sulperazon) is inactive

Moxifloxacin

Bronchiectasis: Pseudomonas cover essential

Tazocin / Timentin / cefepime + macrolide

Fluoroquinolone + aminoglycoside

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Case 1 Patient was started on Augmentin +

clarithromycin empirically 3 days later, fever persisted, chest X-ray showed

progressive pneumonia Endotracheal aspirate (WBC +++, few epithelial

cells) grew heavy Streptococcus pneumoniae, with penicillin MIC > 4mcg/ml

Questions Risk factors for penicillin-resistant S. pneumoniae? Appropriate management in this case?

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Penicillin resistant Streptococcus pneumoniae(PRSP)

Risk factors

Age > 65 years

Beta-lactam therapy in past 3 months

Alcoholism

Multiple medical comorbidities (e.g. immunosuppressive illness or medications)

Exposure to a child in a day care centre

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Penicillin resistant Streptococcus pneumoniae(PRSP)

If susceptible, penicillin group is the drug of choice for Streptococcus pneumoniae

Check susceptibility and MIC if resistant to penicillin

Penicillin susceptible (MIC 0.1 mcg/ml) Penicillin G, amoxicillin

Penicillin resistant (0.1< MIC 1.0 mcg/ml) High dose penicillin G or ampicillin, cefotaxime /

ceftriaxone

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Penicillin resistant Streptococcus pneumoniae(PRSP)

Penicillin resistant (MIC > 2.0 mcg/ml) Vancomycin rifampin High dose cefotaxime tried in meningitis Non-meningeal infection: cefotaxime / ceftriaxone, high

dose ampicillin, carbapenems, or fluoroquinolone (levofloxacin, moxifloxacin)

Multidrug resistant (MDRSP, resistant to any 2 of the following: penicillins, erythromycin, tetracycline, macrolides, cotrimoxazole) Vancomycin rifampin Clindamycin, levofloxacin, moxifloxacin could be tried

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Penicillin resistant Streptococcus pneumoniae(PRSP)

Any alternative for PRSP / MDRSP in respiratory tract infection?

Newer agents

Telithromycin (Ketek®)

Linezolid (Zyvox®)

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Telithromycin (Ketek®) A ketolide (structurally related to macrolides) Spectrum of activity

Group A, B, C and G Streptococci, Streptococcus pneumoniae (including multidrug resistant strains), MSSA

Listeria monocytogenes, Neisseria meningitidis, Moraxella catarrhalis, Haemophilus influenzae

Legionella, Chlamydia, Mycoplasma No activity vs. MRSA, GRE, or any enteric gram-negative

bacteria

Indications Mild to moderate community acquired pneumonia

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Linezolid (Zyvox®) An oxazolidinedione

Spectrum of activity and indications Vancomycin-Resistant Enterococcus faecium infections, including

cases with concurrent bacteremia Nosocomial pneumonia caused by MSSA or MRSA or Strep

pneumoniae (including MDRSP) Complicated skin and skin structure infections, including diabetic

foot infections, without concomitant osteomyelitis, caused by MSSA or MRSA, Strep pyogenes, or Strep agalactiae

Uncomplicated skin and skin structure infections caused by MSSA or Strep pyogenes.

Community-acquired pneumonia caused by Strep pneumoniae (including MDRSP), including cases with concurrent bacteremia, or MSSA

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Case 2 M/56

Presented with skin redness, warmth, swelling, tenderness on his right lower limb, a pocket of fluid palpated

Diagnosis: cellulitis with pus formation

Question

Empirical treatment?

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Skin and soft tissue infection Cellulitis

Microbiology

Staphylococcus, Streptococci

Streptococci more likely when cellulitis is well demarcated and there are no pockets of pus or evidence of vein thrombosis

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Staphylococcus aureus If susceptible, penicillinase-resistant penicillins are the

drugs of choice for methicillin-susceptible Staphylococcus aureus (MSSA)

Drug of choice Cloxacillin, flucloxacillin

Cefazolin, cephalexin (penicillin allergic but tolerate cephs)

With beta-lactamase inhibitor As two-agent combination in Augmentin, Unasyn

Erythromycin, clindamycin (if penicillin allergic)

The above antibiotics also have good activity vs. Streptococci

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Case 2 Skin tenderness and redness did not appear to

improve despite Augmentin has been given Pus grew MRSA after 2 days

R to methicillin, cephalothin, erythromycin S to clindamycin, vancomycin, gentamicin,

cotrimoxazole

Patient is clinically stable

Questions What is the drug of choice in MRSA infection? Can clindamycin be used in this case?

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Methicillin resistant Staphylococcus aureus(MRSA) Healthcare-associated

Endemic in hospitals, old age homes

Risk factors Hospitalization in previous 1

year Recent surgery Old age home residence Renal dialysis Exposure to invasive devices Employment in a healthcare

institute

Community-associated Do not have usual risk

factors associated with HA-MRSA

More common in the following in overseas countries Children with chronic skin

condition Prisoners Military personnel Aboriginals Injection drug users The homeless Contact sports athletes

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Methicillin resistant Staphylococcus aureus(MRSA)

Healthcare-associated

Multiresistant to

Clindamycin

Aminoglycosides

Tetracyclines

Fluoroquinolones

Community-associated

Often remains susceptible to

Clindamycin

Aminoglycosides

Tetracyclines

Fluoroquinolones

More associated with skin/soft tissue infections and severe necrotizing pneumonia

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Methicillin resistant Staphylococcus aureus(MRSA)

Obtain culture for susceptibility testing right before empirical antibiotics!

Treatment (as per Sanford Guide 37th ed)

Community-associated Mild to moderate infections

Abscess, afebrile, immunocompetent, outpatient

Cotrimoxazole / doxycycline / minocycline rifampin

Clindamycin (do not use if R to erythromycin due to inducible resistance)

Abscess with fever, outpatient

Cotrimoxazole-DS + rifampin or linezolid

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Methicillin resistant Staphylococcus aureus(MRSA)

Clinical guideline for management of suspected CA-MRSA infections (15 March 2007) Most CA-MRSA isolates in HKSAR are susceptible to:

Cotrimoxazole

Doxycycline, minocycline

Clindamycin

Moxifloxacin

Out-patient oral therapy available for uncomplicated CA-MRSA skin and soft tissue infection

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Methicillin resistant Staphylococcus aureus(MRSA)

Antimicrobials for outpatient therapy of uncomplicated skin and soft tissue

infections (Clinical guideline for management of suspected CA-MRSA

infections,15 March 2007)

Agent Potential

advantage

Precautions Usual adult dose

(oral)

Cotrimoxazole Oral Not for patient with sulfa

allergy / G6PD

960mg bd

Doxycycline High skin

concentration

Not for children <12 yo

or pregnant women

200mg once, then

100mg bd

Minocycline As above As above 100mg bd

Clindamycin Inhibit toxin

production

Inducible resistance if

erythromycin resistant

300-450mg tds

Moxifloxacin Oral Resistance may

develop during therapy

400mg qd

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Methicillin resistant Staphylococcus aureus(MRSA)

Appropriate treatment in uncomplicated skin and soft tissue infection

Cotrimoxazole, doxycycline, minocycline or moxifloxacin

Clindamycin is not reliable in this case

Inducible clindamycin resistance due to erythromycin resistance

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Case 2 What to do if

the organism is resistant to agents listed above and vancomycin, and

Infection is complicated (unstable patient, extensive involvement, severe sepsis, etc)?

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VISA and VRSA VISA: vancomycin-intermediate Staph aureus

VRSA: vancomycin-resistant Staph aureus

Classified based on minimum inhibitory concentration (MIC) (CDC definition)

VISA: vancomycin MIC is 4-8 µg/ml

VRSA: vancomycin MIC is >16 µg/ml

(HA Central Committee on Infectious Diseases) Susceptible: vancomycin MIC is ≤ 4µg/ml

VISA: vancomycin MIC is 8-16 µg/ml

VRSA: vancomycin MIC is >32 µg/ml

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Another version of …?

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Bad Cellulitis

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MRSA

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VISA and VRSA More likely to develop among patients with

Underlying conditions (including renal failure) which predispose the patient to MRSA colonization;

Indwelling medical devices; and/or

MRSA infection requiring treatment with vancomycin for a prolonged period

Usually isolated during vancomycin (or teicoplanin) therapy for MRSA infections which fail to respond

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VISA and VRSA Linezolid (Zyvox®)

(discussed in PRSP session)

Quinupristin/dalfopristin (Synercid®)

Dalbavancin (Zeven®)

Still under investigation

Daptomycin (Cubicin®)

Tigecycline (Tygacil®)

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Linezolid (Zyvox®)Demonstrate bacteriostatic action vs. VISA

and VRSA

Indications Complicated skin and skin structure infections,

including diabetic foot infections, without concomitant osteomyelitis, caused by MSSA or MRSA, Strep pyogenes, or Strep agalactiae

Uncomplicated skin and skin structure infectionscaused by MSSA or Strep pyogenes

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Tigecycline (Tygacil®) A glycylcycline

Derived from minocycline

A very broad spectrum antibiotic

Covers many resistant strains of Gram-positive, Gram-negative, and anaerobic organisms

Note active vs. Pseudomonas

Both in vitro and in vivo activities have been demonstrated against MSSA, MRSA, and VISA

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Tigecycline (Tygacil®) Indications

Complicated skin and skin structure infections by Escherichia coli Enterococcus faecalis

(vancomycin-susceptible isolates only)

Staphylococcus aureus (Methi-S or Methi-R)

Streptococcus agalactiae Streptococcus anginosus grp. Streptococcus pyogenes Bacteroides fragilis

Complicated intra-abdominal infections by Citrobacter freundii Enterobacter cloacae E. coli, K. oxytoca, K.

pneumoniae Enterococcus faecalis (Vanco-

S isolates only) Staphylococcus aureus

(Methi-S or Methi-R) Streptococcus anginosus

group Bacteriodes fragilis Clostridium perfringens Peptostreptococcus micros

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Gram-negative superbugsResistant Gram-negative bacteria terminology

ESBL-producing

Enterobacteriaceae

Extended spectrum beta-lactamases producing

Enterobacteriaceae, e.g. Escherichia coli,

Klebsiella pneumoniae

MRPA (MDR-PA) Multidrug resistant Pseudomonas aeruginosa

MRAB (MDR-AB) Multidrug resistant Acinetobacter baumannii

Pan-resistant Pseudomonas aeruginosa /

Acinetobacter baumannii

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Case 3 M/59

Presented with 2-day history of right upper quadrant pain, fever, jaundice

Emesis x 2 past 24 hours, dark color urine

Elevated LFT

Radiologic finding: dilated common bile duct, no increase in gallbladder size

Diagnosis: acute cholangitis

Question What is the empirical therapy?

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Acute cholangitis/cholecystitis Microbiology

Gram negative enterics

E. coli, Klebsiella spp., Proteus spp.

Anerobes

Bacteriodes fragilis, Clostridium spp.

Enterococcus

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Acute cholangitis/cholecystitis Adequate drainage is essential

Empirical treatment complementary to drainage

Augmentin/Unasyn ± aminoglycoside

Timentin

Cefuroxime + metronidazole

Ciprofloxacin (if beta-lactam allergic)

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Case 3 Biliary drainage performed with cefuroxime +

metronidazole pre- and post-operation Became septic (with high fever, tachycardia, WBC

> 12 x 109/L) 2 days post-op Blood culture grew E. coli (ESBL-producing),

moderately sensitive to Augmentin, sensitive to Sulperazon and imipenem

Question What is the appropriate treatment? Can Augmentin or Sulperazon be used?

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Enterobacteriaceae Susceptible strains of E. coli and Klebsiella are

sensitive to

Augmentin/Unasyn

Cefuroxime (if resistant to above)

Other anti gram-negative penicillins/cephs also work

Fluoroquinolones (if allergic to beta-lactams)

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ESBL-producing Enterobacteriaceae Extended-spectrum beta-lactamases

Any bacterial enzymes that are capable of inactivating third generation cephalosporins

Generally regarded as resistant to penicillins and cephalosporins

Drug of choice Urinary tract infection

Cotrimoxazole, Augmentin, nitrofurantoin, levofloxacin / ciprofloxain

Other serious infections Carbapenems: imipenem, meropenem, ertapenem (reliable activity vs.

ESBL-producing Enterobacteriaceae) Fluoroquinolone + aminoglycoside

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Case 3 Augmentin and Sulperazon are not appropriate

Patient is clinically septic (likely due to the ESBL-producing strain of E. coli)

The strain is only apparently susceptible to the above agents

Appropriate agent

Ertapenem (no activity vs. Pseudomonas)

Imipenem (when activity vs. Pseudomonas required)

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Pseudomonas aeruginosa Gram-negative bacilli

Frequently present in small numbers in the normal intestinal flora and on the skin of humans and is the major pathogen

Causes diseases in patients with abnormal host defenses, e.g. When mucous membranes and skin are disrupted

When intravenous or urinary catheters are used

When neutropenia is present (as in chemotherapy)

Intrinsically resistant to many antibiotics

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Pseudomonas aeruginosa Drug of choice

Antipseudomonal penicillins/cephalosporins Piperacillin, piperacillin/tazobactam (Tazocin), ticarcillin/clavulanate

(Timentin)

Ceftazidime, cefoperazone, cefepime

Carbapenems Imipenem, meropenem (NOT ertapenem)

Aminoglycosides Gentamicin, tobramycin, amikacin

Fluoroquinolones Ciprofloxacin, levofloxacin (less activity than cipro)

Often a two-drug combination is employed except in uncomplicated UTI

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Piperacillin vs. Tazocin Tazobactam in Tazocin®

Tazobactam is a beta-lactamase inhibitor

Renders the combination of Tazocin® more active against

Gram positive: MSSA

Gram negative: Haemophilus influenzae and others

Anaerobe: Bacteroides fragilis

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Piperacillin vs. Tazocin Tazobactam in Tazocin®

For Pseudomonas aeruginosa susceptible to piperacillin, Tazocin 4.5g Q8H IV and Piperacillin 4g Q8H IV are equivalent

At common usual dose (HA Corp drug price as of May 2007)

Piperacillin 4g/vial: $56

Tazocin® 4.5g/vial: $108

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Multidrug resistantGram-negative organisms

Any treatment options for

ESBL-producing Enterobacteriaceae, or

Pseudomonas aeruginosa,

that are pan-resistant?

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Colistin (Colomycin®) Indeed an old, toxic drug!

a.k.a. Polymyxin E, colistimethate sodium Now being used with increasing frequency due to necessity

(multidrug resistant Gram-negatives) Risk of neurotoxicity and nephrotoxicity

Spectrum of activity (check susceptibility!) Pseudomonas aeruginosa, Acinetobacter spp. E. coli and Klebsiella (incl. ESBL-producing strains), Enterobacter

spp. Citrobacter spp, Hemophilus spp.

Indications Disease due to Gram-negative bacteria, acute or chronic due to

sensitive strains of certain gram-negative bacilli

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Acinetobacter baumannii Common cause of nosocomial infection especially

in ICU setting

Drug of choice

Ampicillin/sulbactam or cefoperazone/sulbactam (sulbactam highly active vs. Acinetobacter) or fluoroquinolone (ciprofloxacin, levofloxacin)

Gentamicin added to prevent resistance and for synergy

Imipenem, meropenem can be used

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Acinetobacter baumannii Acinetobacter strains are often resistant to

antimicrobial agents

Other agents with in vitro activity vs. Acinetobacter baumannii

Minocycline / doxycycline

Tigecycline

Colistin

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Sinusitis: X-raysStreptococcus PneumoniaHemophillus InfluenzaMorexalla Catarrhalis

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Sinusitis: Treatment Mild Acute Bacterial Sinusitis (ABS)

Amoxicillin

Amoxicillin/clavulanate

Cefuroxime axetil

Cefpodoxime

Or antistrep. fluoroquinolones:

Levofloxacin

Moxifloxacin

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Sinusitis: Treatment Drug option in the case of allergies to penicillin and

cephalosporin with Mild ABS:

Doxycycline

Trimethoprim/sulfamethoxizole

Azithromycin

Clarithromycin

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Sinusitis: Treatment Drug option in the case of allergies to penicillin and

cephalosporin with Moderate to Severe ABS:

Antipneumococcal fluoroquinolone:

Levofloxacin

Moxifloxacin

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Intra-abdominal infections Common bacterial organisms

GNRs

E. coli, Klebsiella, Proteus

Enterococcus and anaerobes also common

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Intra-abdominal infections Empiric therapy should cover GNRs and anaerobes

(Bacteroides fragilis)

Ampicillin/sulbactam

Ticarcillin/clavulanate

Piperacillin/tazobactam

Carbepenem: imipenem, meropenem

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Intra-abdominal infections Cefoxitin no longer has reliable coverage against B.

fragilis

Cefotetan, another second generation cephalosporin, might be back on the market soon

Pts allergic to penicillin could use:

Fluoroquinolone + metronidazole

For severely ill, cover Pseudomonas

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Pregnancy Avoid tetracycline class

Staining of teeth and bones in babies

Avoid sulfa drugs in the third trimester

May be associated with kernicterus

Avoid aminoglycosides

Kidney toxicities

Fluoroquinolones – class C

Concerns about cartilage development

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Pregnancy Treat the Mother first and the baby will appreciate it

Penicillins and cephalosporins are generally safe in pregnancy.

Macrolides are generally safe

They may increase nausea early on

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Meningitis: Treatment Adults and children>2 months old:

High dose ceftriaxone or cefotaxime

+

Vancomycin

Ampicillin can be added if Listeria monocytogenes is a consideration

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Meningitis: Use of steroids Give dexamethasone before or with the first dose of

antibiotics.

Corticosteroid treatment has been shown to decrease neurologic complications in children and is now recommended in adults.

Continue steroids every 6 hours for four days.

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Antibiotic Stewardship Program in Hospital Authority Multidisciplinary, programmatic, prospective,

interventional approach to optimizing the use of antimicrobial agents

The multidisciplinary team typically includes

Clinical microbiologists

Infectious diseases specialists

Clinical pharmacists

Infection control practitioners

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Antibiotic Stewardship Program Involves

Prescribing antimicrobial therapy only when it is beneficial to the patient

Targeting therapy to the desired pathogens

Using the appropriate drug, dose, and duration

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Antibiotic Stewardship Program Should not be viewed simply as reduced use or a

strategy for cost containment

A strategy to enhance patient safety by

Minimizing exposure to drugs

Performing dose adjustments

Reducing redundant therapy

Targeting therapy to the likely pathogens

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Big gun audit Big gun audit

Targets 2 types of antibiotics

Broad-spectrum antibiotics

Tienam, Meropenem, Ceftazidime, Cefepime, Tazocin, Sulperazon

All these agents have good Gram-negative as well as Pseudomonas coverage

Anti Gram-positive antibiotics

Vancomycin and teicoplanin

Active vs. methicillin-resistant Staphylococcus aureus

To be used as second-line agents

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IV-PO switch IV-PO switch

Criteria (as per IMPACT)

1. No indication for IV therapy

2. Patient is afebrile for ≥ 8 hours

3. WBC count is normalizing

Falling towards or < 10 x 109/L

4. Signs and symptoms related to infection are improving

5. Patient is not neutropenic

Neutrophil count > 2 x 109/L

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IV-PO switch IV-PO switch

Criteria (as per IMPACT) 6. Able to take drugs by mouth (non-NPO)

7. No continuous nasogastric suctioning

8. No severe nausea or vomiting, diarrhea, gastrointestinal obstruction, motility disorder

9. No malabsorption syndrome

E.g. small bowel syndrome due to resection

10. No pancreatitis or active gastrointestinal bleeding or other conditions that contraindicated to the use of oral medications

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IV-PO switch IV-PO switch

Points to note

Prescribe dose based on creatinine clearance when antimicrobials require renal dosage adjustment

Augmentin®, Unasyn®, clarithromycin, ciprofloxacin, levofloxacin

Drug interactions

Oral ciprofloxacin and levofloxacin with antacid, sucralfate, didanosine, dairy products and enteral feeds

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Reducing bacterial resistance IMPACT (Interhospital Multi-disciplinary

Programme on Antimicrobial ChemoTherapy)

Available for download at: HKU Centre of Infection

http://www.hku.hk/hkucoi/impact.pdf

DH Centre for Health Protection

http://www.chp.gov.hk/files/pdf/reducing_bacterial_resistance_with_impact.pdf

HA intranet

http://ha.home/ho/ps/impact.pdf

Most updated: third version 2005 (version 3.0)

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IMPACT guideline Contents of IMPACT guideline

Local antibiotic resistance

Guidelines for selected antimicrobial use, e.g.

Vancomycin

Ceftazidime

Imipenem/meropenem/ertapenem

Once daily aminoglycosides

Selected antifungal agents

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Useful guides to antimicrobial therapy Sanford Guide

Covers a broad range of infectious diseases

IMPACT With commonly prescribed empirical therapy and

useful local resistance information

Local antibiogram Bacterial resistance specific to an institution or a cluster

of institutions

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Conclusion New antibiotics intended to treat complicated

diseases are under investigation

Need to protect our antibiotic arsenal

Justified use of antimicrobials not only treats infections, but also improves patient outcomes and reduces the risk of development of bacterial resistance

Adherence to clinical guidelines, antimicrobial stewardship program and education helps to promote appropriate antimicrobial use

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Conclusion Last but not least…

Infection control is of utmost importance in reducing risk of infection, use of antibiotics and hence emergence of bacterial resistance Hand hygiene

Appropriate isolation / contact restriction

Prompt reporting of certain infectious diseases (e.g. MRSA infections)

Many more!

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Thank You