Cronobacter Support
03-20-2009, 01:28 PM
Medical Care cont'd...
Aminoglycosides
Aminoglycoside resistance is relatively common and varies widely among centers.
As with other members of Enterobacteriaceae, this resistance results from the production of different aminoglycoside-inactivating enzymes.
Quinolones and TMP-SMZ
Resistance to fluoroquinolones is relatively rare but may be high in some parts of the world.
Resistance to TMP-SMZ is more common.
Colistin and polymyxin B: These drugs are being used more frequently to treat serious infection caused by multidrug-resistant organisms, sometimes as monotherapy or in combination with other antibiotics. Clinical experience, including documentation of success rates and attributable mortality is broadening.24 Heteroresistance to colistin was demonstrated in a few Enterobacter isolates collected from ICU patients and was best identified using broth microdilution, agar dilution, or E-test methods.25 Polymyxin B was not as active against Enterobacter species as it was against other Enterobacteriaceae but did demonstrate an MIC50 of less than or equal to 1, with 83% of Enterobacter isolates considered susceptible.26
Surgical Care
Surgical care is indicated as for other sources of infection: drainage or debridement of abscesses, infected collections, or osteomyelitic foci.
In some instances, the clinician must consider this option instead of percutaneous drainage with CT guidance. The severity of the infection and the size of the collection to be drained are among the parameters to consider when choosing the best option for the patient.
For endocarditis, valvular replacement is also indicated, particularly in patients with emboli or intractable heart failure.
Consultations
Enterobacter species cause severe and frequently life-threatening infections that can originate in virtually any body compartment. Enterobacter infection warrants consultation with many different subspecialists.
Consultation with an infectious diseases specialist helps in the selection of antimicrobial agents, taking into account the multiple mechanisms of resistance to different classes of antimicrobial agents and the lack of correlation between crude in vitro susceptibility results and true clinical efficacy for most of the beta-lactams.
Intensive care specialists, when appropriate, can help in the management of severe sepsis or septic shock.
General internal medicine and/or medical subspecialists (eg, cardiologists, gastroenterologists, nephrologists, rheumatologists, pulmonologists) may be helpful.
Surgeons may help with the drainage of infected collections, if indicated, as well as with debridement of necrotic tissues.
Consult neonatologists for neonatal sepsis and, possibly, general pediatricians or pediatric subspecialists (including pediatric surgeons).
Radiologists and nuclear medicine physicians may help select the best imaging study according to patient's specific problems and (radiologists) may be needed to perform percutaneous drainage of infected collections.
A microbiologist can provide valuable assistance by educating clinicians regarding the correct interpretation of susceptibility testing with this organism.
Medication
The goals of pharmacotherapy are to eradicate the infection, to reduce morbidity, and to prevent complications.
Antibiotics
The antimicrobials most indicated in Enterobacter infections include carbapenems, fourth-generation cephalosporins, aminoglycosides, fluoroquinolones, and TMP-SMZ.
Carbapenems have the best activity against E cloacae, E aerogenes, and others. They are not affected by ESBLs. Imipenem-cilastatin and meropenem are used most often. Ertapenem, approved more recently, is gaining clinical experience.27 Doripenem, recently approved in the United States, is likely to be as effective.
First-generation and second-generation cephalosporins are inactive against Enterobacter infections. Third-generation cephalosporins frequently show good in vitro activity against these organisms, but, as explained above, a significant risk of developing full resistance during therapy exists. Resistance develops much less frequently with fourth-generation cephalosporins because they are relatively stable to AmpC beta-lactamase but not (so far) to the less frequently encountered ESBLs (see Medical Care). Third-generation cephalosporins are not indicated for the treatment of severe Enterobacter infections, perhaps with the notable exception of uncomplicated infections.
Fluoroquinolones have good bactericidal activity against gram-negative bacilli; their bioavailability ranges from very good to excellent (with the exception of norfloxacin). Newer quinolones have increased their spectrum toward gram-positive organisms and, in some cases, toward anaerobes. Ciprofloxacin and levofloxacin have the best activity against gram-negative bacilli and should generally be selected over the newer fluoroquinolones if clinically indicated.
Continued post from emedicine.medscape.com/article/216845-treatment
Aminoglycosides
Aminoglycoside resistance is relatively common and varies widely among centers.
As with other members of Enterobacteriaceae, this resistance results from the production of different aminoglycoside-inactivating enzymes.
Quinolones and TMP-SMZ
Resistance to fluoroquinolones is relatively rare but may be high in some parts of the world.
Resistance to TMP-SMZ is more common.
Colistin and polymyxin B: These drugs are being used more frequently to treat serious infection caused by multidrug-resistant organisms, sometimes as monotherapy or in combination with other antibiotics. Clinical experience, including documentation of success rates and attributable mortality is broadening.24 Heteroresistance to colistin was demonstrated in a few Enterobacter isolates collected from ICU patients and was best identified using broth microdilution, agar dilution, or E-test methods.25 Polymyxin B was not as active against Enterobacter species as it was against other Enterobacteriaceae but did demonstrate an MIC50 of less than or equal to 1, with 83% of Enterobacter isolates considered susceptible.26
Surgical Care
Surgical care is indicated as for other sources of infection: drainage or debridement of abscesses, infected collections, or osteomyelitic foci.
In some instances, the clinician must consider this option instead of percutaneous drainage with CT guidance. The severity of the infection and the size of the collection to be drained are among the parameters to consider when choosing the best option for the patient.
For endocarditis, valvular replacement is also indicated, particularly in patients with emboli or intractable heart failure.
Consultations
Enterobacter species cause severe and frequently life-threatening infections that can originate in virtually any body compartment. Enterobacter infection warrants consultation with many different subspecialists.
Consultation with an infectious diseases specialist helps in the selection of antimicrobial agents, taking into account the multiple mechanisms of resistance to different classes of antimicrobial agents and the lack of correlation between crude in vitro susceptibility results and true clinical efficacy for most of the beta-lactams.
Intensive care specialists, when appropriate, can help in the management of severe sepsis or septic shock.
General internal medicine and/or medical subspecialists (eg, cardiologists, gastroenterologists, nephrologists, rheumatologists, pulmonologists) may be helpful.
Surgeons may help with the drainage of infected collections, if indicated, as well as with debridement of necrotic tissues.
Consult neonatologists for neonatal sepsis and, possibly, general pediatricians or pediatric subspecialists (including pediatric surgeons).
Radiologists and nuclear medicine physicians may help select the best imaging study according to patient's specific problems and (radiologists) may be needed to perform percutaneous drainage of infected collections.
A microbiologist can provide valuable assistance by educating clinicians regarding the correct interpretation of susceptibility testing with this organism.
Medication
The goals of pharmacotherapy are to eradicate the infection, to reduce morbidity, and to prevent complications.
Antibiotics
The antimicrobials most indicated in Enterobacter infections include carbapenems, fourth-generation cephalosporins, aminoglycosides, fluoroquinolones, and TMP-SMZ.
Carbapenems have the best activity against E cloacae, E aerogenes, and others. They are not affected by ESBLs. Imipenem-cilastatin and meropenem are used most often. Ertapenem, approved more recently, is gaining clinical experience.27 Doripenem, recently approved in the United States, is likely to be as effective.
First-generation and second-generation cephalosporins are inactive against Enterobacter infections. Third-generation cephalosporins frequently show good in vitro activity against these organisms, but, as explained above, a significant risk of developing full resistance during therapy exists. Resistance develops much less frequently with fourth-generation cephalosporins because they are relatively stable to AmpC beta-lactamase but not (so far) to the less frequently encountered ESBLs (see Medical Care). Third-generation cephalosporins are not indicated for the treatment of severe Enterobacter infections, perhaps with the notable exception of uncomplicated infections.
Fluoroquinolones have good bactericidal activity against gram-negative bacilli; their bioavailability ranges from very good to excellent (with the exception of norfloxacin). Newer quinolones have increased their spectrum toward gram-positive organisms and, in some cases, toward anaerobes. Ciprofloxacin and levofloxacin have the best activity against gram-negative bacilli and should generally be selected over the newer fluoroquinolones if clinically indicated.
Continued post from emedicine.medscape.com/article/216845-treatment