2010 jun (94): treatment guidelines - drugs for bacterial infections

Published by The Medical Letter, Inc. • 1000 Main Street, New Rochelle, NY 10801 • A Nonprofit Publication IN THIS ISSUE (starts on next page)
Drugs for Bacterial Infections .p 43
Important Copyright Message
The Medical Letter® publications are protected by US and international copyright laws.
Forwarding, copying or any distribution of this material is prohibited.
Sharing a password with a non-subscriber or otherwise making the contents of this site availableto third parties is strictly prohibited.
By accessing and reading the attached content I agree to comply with US and internationalcopyright laws and these terms and conditions of The Medical Letter, Inc.
For further information click:
or call customer service at: 800-211-2769
FORWARDING OR COPYING IS A VIOLATION OF US AND INTERNATIONAL COPYRIGHT LAWS
The Medical Letter publications are protected by US and international copyright laws.
Forwarding, copying or any other distribution of this material is strictly prohibited.
For further information call: 800-211-2769
Published by The Medical Letter, Inc. • 1000 Main Street, New Rochelle, NY 10801 • A Nonprofit Publication Online Tables

Drugs for Bacterial Infections
The text below reviews some common bacterial infec- if the patient was recently treated with antibiotics, is tions and their treatment. The recommendations made known to be colonized, has a history of recent hospital- here are based on the results of susceptibility studies, ization, or is in a geographic area of high prevalence.7,8 clinical trials and the opinions of Medical Letter con-sultants. A table listing the drugs of choice and alterna- Treatment of MRSA – Treatment should be guided
tives for all bacterial pathogens can be found online at by the severity of infection and susceptibility tests.
Patients with serious skin and soft tissue infections listing oral antibacterial drug dosages begins on page suspected to be caused by CA-MRSA should be treat- 46. Parenteral drug dosages can be found online at ed empirically with vancomycin, linezolid or dapto- mycin. Tigecycline can be used, but because it has avery broad spectrum of activity, it is best reserved for INFECTIONS OF SKIN, SOFT TISSUE AND
patients unable to take other drugs or those with doc- CA-MRSA strains often are susceptible to trimetho- SKIN AND SOFT TISSUE — Uncomplicated skin
prim/sulfamethoxazole, clindamycin and tetracy- and skin structure infections in immunocompetent clines; nosocomial strains often are not. For small patients are most commonly due to Staphylococcus abscesses and less serious CA-MRSA skin or soft tis- aureus, Streptococcus pyogenes (group A streptococ- sue infections, drainage or local therapy alone may be ci) or Streptococcus agalactiae (group B streptococ- effective. When it is not, oral trimethoprim/sul- ci). Complicated skin and skin structure infections, famethoxazole, minocycline, doxycycline, clin- such as those that occur in patients with burns, dia- damycin or linezolid could be tried.10 Fluoroquinolones betes mellitus, infected pressure ulcers and traumatic should not be used empirically to treat MRSA infec- or surgical wound infections, are more commonly tions because resistance is common and increasing in polymicrobial and often include gram-negative both nosocomial and community settings.
bacilli such as Escherichia coli and Pseudomonasaeruginosa. Group A streptococci, S. aureus or Treatment of Non-MRSA Infections – For uncompli-
Clostridium spp., with or without other anaerobes, cated infections unlikely to be due to MRSA (no recent
can cause fulminant soft tissue infection and necro- hospitalizations, etc.), an antistaphylococcal penicillin sis, particularly in patients with diabetes mellitus.1 such as dicloxacillin or a first-generation cephalosporinsuch as cephalexin would be a reasonable choice. If the Methicillin-resistant S. aureus (MRSA) – In the past
patient requires hospitalization, the same classes of few years, methicillin-resistant S. aureus strains drugs (nafcillin, cefazolin) can be given intravenously (MRSA) have become the predominant cause of sup- (IV). Clindamycin or vancomycin would be a reason- purative skin infection in many parts of the US.2-4 able choice for patients who are allergic to a beta-lac- Community-acquired MRSA (CA-MRSA) usually causes furunculosis and abscesses, but necrotizingfasciitis and sepsis can occur.5,6 For complicated infections that could be polymicrob-
ial and are unlikely to be MRSA, ampicillin/sulbac-
MRSA should be considered a likely cause of infection tam, piperacillin/tazobactam, ticarcillin/clavulanate, Federal copyright law prohibits unauthorized reproduction by any means and imposes severe fines.
Drugs for Bacterial Infections
imipenem or meropenem would be reasonable empiric trimethoprim/sulfamethoxazole, metronidazole, line- monotherapy. If group A streptococcus or Clostridium zolid or moxifloxacin can be used for chronic spp. is the likely cause, a combination of clindamycin osteomyelitis depending on the susceptibility of the and a penicillin is recommended.11 In severely ill patients, vancomycin or linezolid should be added MENINGITIS
until MRSA is ruled out. Surgical debridement isessential to the management of necrotizing skin and The organisms most commonly responsible for com- munity-acquired bacterial meningitis in children andadults are Streptococcus pneumoniae (pneumococcus) BONE AND JOINT — Staphylococcus aureus is the
and Neisseria meningitidis, which cause about 80% of most common cause of osteomyelitis. Streptococcus
all cases.16 As a result of childhood immunization, pyogenes and S. agalactiae are less common meningitis due to Haemophilus influenzae type b has pathogens. Salmonella spp. can cause osteomyelitis in decreased markedly in adults and children and pneu- patients with sickle cell disease, as can other gram- mococcal meningitis has declined in children.17 negative bacteria (Escherichia coli, Pseudomonas Enteric gram-negative bacteria cause meningitis in spp.), particularly in patients who have had orthopedic neonates, the elderly, and in patients who have had procedures or have open fractures or vertebral infec- recent nosocomial infections or neurosurgery, or are tion. Infections of the feet are common in diabetic immunosuppressed.18 Group B streptococcus often patients, often involve both bone and soft tissue, and causes meningitis in neonates or in the elderly. Listeria may be polymicrobial, including both aerobic and monocytogenes may be the cause in pregnant women, neonates, patients >50 years old and in immunosup-pressed patients.19 Septic arthritis may be due to S. aureus, S. pyogenes
or Streptococcus pneumoniae, gram-negative bacteria
For empiric treatment of meningitis in adults and
or, in sexually active patients, Neisseria gonor- children more than two months old, high-dose cef-
rhoeae.13 Coagulase-negative staphylococci and S. triaxone or cefotaxime plus vancomycin is generally aureus are the most common causes of prosthetic joint recommended; vancomycin is given at a dosage of 15- 20 mg/kg every 8-12 hours to reach a serum troughlevel of 15-20 mcg/mL to cover highly penicillin- or For empiric treatment of acute osteomyelitis unlikely to cephalosporin-resistant pneumococci.20 Vancomycin be caused by MRSA, IV administration of an anti- should be stopped if the etiologic agent proves to be staphylococcal penicillin such as nafcillin or a first-gen- susceptible to ceftriaxone or cefotaxime. Ampicillin, eration cephalosporin such as cefazolin would be appro- sometimes in combination with gentamicin for severe- priate. Many Medical Letter consultants would use van- ly ill patients, is added in patients in whom L. monocy- comycin until culture results are available. Ceftriaxone would be a reasonable first choice for empiric treatmentof a joint infection to include coverage for S. aureus and Neonatal meningitis is most often caused by group B
N. gonorrhoeae. For both bone and joint infections, IV streptococci, gram-negative enteric organisms or L. penicillin or ceftriaxone can be used to treat monocytogenes. For meningitis in the first two months Streptococcus spp. If MRSA or methicillin-resistant of life, while waiting for the results of cultures and sus- coagulase-negative staphylococci are the pathogens, ceptibility tests, many Medical Letter consultants use vancomycin, daptomycin or linezolid should be used.
ampicillin plus ceftriaxone or cefotaxime, with or Ceftriaxone, ceftazidime or cefepime would be a good option for empiric treatment of bone and joint infectionswith gram-negative bacteria; ciprofloxacin would be an For treatment of nosocomial meningitis, vancomycin
and a cephalosporin with good activity againstPseudomonas such as ceftazidime are appropriate. In For prosthetic joint infections, rifampin is often hospitals where gram-negative bacilli that produce added to antistaphylococcal therapy because of its extended-spectrum ß-lactamases are common, use of effect on staphylococcal isolates that are adherent to meropenem or doripenem should be considered Chronic osteomyelitis, common in complicated diabet- Ceftriaxone or cefotaxime can often be used safely to ic foot infection, usually requires surgical debridement treat meningitis in penicillin-allergic patients. When
of involved bone followed by 4-8 weeks of antibacter- allergy truly prevents the use of a cephalosporin, chlo- ial therapy. Well-absorbed oral antibacterials such as ramphenicol can be given for initial treatment, but may Treatment Guidelines from The Medical Letter • Vol. 8 ( Issue 94) • June 2010
Drugs for Bacterial Infections
not be effective if the infecting pathogen is an enteric ciprofloxacin or ceftazadime should be considered. gram-negative bacillus or L. monocytogenes, or insome patients with penicillin-resistant pneumococcal The most common bacterial cause of acute pharyngi-
meningitis. For coverage of enteric gram-negative tis in adults and children is group A streptococci.
bacilli and P. aeruginosa in patients with penicillin and Penicillin, amoxicillin or a macrolide is usually given cephalosporin allergy, aztreonam could be used.
for 10 days.26 In the US, about 5% of pharyngeal iso- Trimethoprim/sulfamethoxazole can be used for treat- lates of group A streptococci are resistant to ment of Listeria meningitis in patients allergic to peni- macrolides.27 In some areas, much higher rates of cillin. As with nonallergic patients, vancomycin should be added to cover resistant pneumococci. PNEUMONIA
A corticosteroid, usually parenteral dexamethasone
(Decadron, and others), given in a dose of 0.15 mg/kg
The pathogen responsible for community-acquired
IV q6h starting before or at the same time as the first bacterial pneumonia (CAP) is often not confirmed,
dose of antibiotics and continued every 6 hours for 4 but S. pneumoniae and the “atypical” pathogens days, has been reported to decrease the incidence of Mycoplasma pneumoniae, Chlamydophila pneumoni- hearing loss in children, particularly with Haemophilus ae (formerly Chlamydia pneumoniae) and Legionella influenzae meningitis, and to decrease mortality rates spp. are frequent pathogens. Among hospitalized
and other neurological complications in adults.21,22 patients with community-acquired bacterial pneu-
The benefits in adults have been most striking in those monia, S. pneumoniae is still probably the most com-
with pneumococcal meningitis. Since the incidence of mon cause. Other bacterial pathogens include H. adverse effects has been low, the potential benefits of influenzae, S. aureus and occasionally other gram-neg- such treatment would appear to outweigh the risks.
ative bacilli and anaerobic mouth organisms.
INFECTIONS OF THE UPPER RESPIRATORY
In ambulatory patients, an oral macrolide (erythromy-
cin, azithromycin or clarithromycin) or doxycycline isgenerally used in otherwise healthy adults.
Acute sinusitis in adults is often due to viral infections.
Pneumococci may, however, be resistant to macrolides When acute sinusitis is bacterial, it is usually caused by and to doxycycline, especially if they are resistant to pneumococci, H. influenzae and Moraxella catarrhalis penicillin.28 For older patients or those with comorbid and can generally be treated with an oral antibacterial illness, a fluoroquinolone may be a better choice. A such as amoxicillin or amoxicillin/clavulanate, fluoroquinolone with good antipneumococcal activity cefuroxime axetil or cefpodoxime, or a fluoroquinolone such as levofloxacin or moxifloxacin is generally used with good antipneumococcal activity such as lev- for adults with comorbidities or antibiotic exposure dur- ofloxacin or moxifloxacin. Monotherapy with a ing the past 90 days.29 Nationally, about 1% of pneu- macrolide (erythromycin, clarithromycin or mococcal isolates are resistant to fluoroquinolones, but azithromycin) is generally not recommended because in some areas the percentage is higher.30 of increasing resistance among pneumococci.
Doxycycline or trimethoprim/sulfamethoxazole may be In community-acquired pneumonia requiring hos-
considered for patients with mild acute bacterial sinusi- pitalization, an IV beta-lactam (such as ceftriaxone
tis who are allergic to penicillins and cephalosporins.23 or cefotaxime) plus a macrolide (erythromycin, In patients with moderate acute bacterial sinusitis or azithromycin or clarithromycin), or a fluoro- with risk factors for infection with drug-resistant S. quinolone with good activity against S. pneumoniae pneumoniae, such as recent antibiotic use, amoxi- (levofloxacin or moxifloxacin) alone, is recommend- cillin/clavulanate or an antipneumococcal fluoro- ed pending culture results.29 If aspiration pneumonia quinolone could be used. Addition of intranasal corti- is suspected, metronidazole or clindamycin can be costeroids may improve symptoms and decrease the added; moxifloxacin or ampicillin/sulbactam, which also have anaerobic activity, are reasonable alterna-tives. In severe cases, CA-MRSA should be consid- Acute exacerbation of chronic bronchitis (AECB) is
ered as a possible pathogen and addition of van- also often viral. When it is bacterial, it may be caused comycin, trimethoprim/sulfamethoxazole or linezolid by H. influenzae, S. pneumoniae or M. catarrhalis and can be treated with the same antimicrobials usedto treat acute bacterial sinusitis.25 In patients with In treating pneumococcal pneumonia due to strains severe COPD, Pseudomonas can be a cause of AECB with an intermediate degree of penicillin resistance and addition of an antipseudomonal agent such as (minimal inhibitory concentration [MIC] 4 mcg/mL), Treatment Guidelines from The Medical Letter • Vol. 8 ( Issue 94) • June 2010
Drugs for Bacterial Infections
Table 1. Dosage of Oral Antibacterial Drugs
Drug Formulations
Pediatric Dosage1
AZITHROMYCIN – generic
CEPHALOSPORINS
CLARITHROMYCIN – generic
CLINDAMYCIN – generic
ERYTHROMYCIN
FLUOROQUINOLONES
FOSFOMYCIN – Monurol
LINEZOLID – Zyvox
1. Doses may vary with site of infection, infecting organism and patient renal function.
2. Suspension formulation also available.
3. Injectable formulation also available.
4. Pediatric dose for post-exposure prophylaxis for anthrax is 10-15 mg/kg bid.
5. For children <11 years of age. Usual dose for children >12 years old is 600 mg q12h.
Treatment Guidelines from The Medical Letter • Vol. 8 ( Issue 94) • June 2010
Drugs for Bacterial Infections
Table 1. Dosage of Oral Antibacterial Drugs (continued)
Usual Pediatric
Formulations
Adult dosage1
KETOLIDE
METRONIDAZOLE
NITROFURANTOIN
PENICILLINS
TETRACYCLINES
generic (capsules)Vibramycingeneric (tablets) TRIMETHOPRIM/SULFAMETHOXAZOLE
VANCOMYCIN2,10
6. One mg is equal to 1600 units.
7. Dosage based on amoxicillin content. For doses of 500 or 875 mg, 500-mg or 875-mg tablets should be used, because multiple smaller tablets would contain too much clavulanate. 125 mg/5 mL oral suspension contains 31.25 mg clavulanate; 250-mg/5 mL oral suspension contains 62.5 mg clavulanate.
8. Dosage based on amoxicillin content.
9. Not recommended for children <8 years old.
10. Some pharmacies use the intravenous formulation for oral administration, which costs less.
Treatment Guidelines from The Medical Letter • Vol. 8 ( Issue 94) • June 2010
Drugs for Bacterial Infections
ceftriaxone, cefotaxime, or high doses of either IV have become the most common class of antibiotic penicillin (12 million units daily for adults) or oral prescribed for UTI, other drugs are generally pre- amoxicillin (1-3 g daily) can be used. For highly resist- ferred for uncomplicated infection due to concerns ant strains (MIC >8 mcg/mL), a fluoroquinolone (lev- about cost-effectiveness and emerging fluoro- ofloxacin or moxifloxacin), vancomycin or linezolid quinolone resistance.33 Acute uncomplicated cysti-
should be used in severely ill patients (such as those tis in women can be effectively and inexpensively
requiring admission to an ICU) and those not respond- treated, before the infecting organism is known, with a three-day course of oral trimethoprim/sulfamethox-azole. In areas where the prevalence of E. coli resist- Hospital-acquired or ventilator-associated pneu-
ant to trimethoprim/sulfamethoxazole exceeds 15% monia is often caused by gram-negative bacilli, espe-
to 20%, or in women with risk factors for resistance, cially P. aeruginosa, Klebsiella spp., E. coli, a 3-day course of a fluoroquinolone such as Enterobacter spp., Serratia spp., and Acinetobacter ciprofloxacin or levofloxacin or a 7-day course of spp.; it can also be caused by S. aureus, usually nitrofurantoin could be substituted.34 A single dose of MRSA. Many of these bacteria are multi-drug resist- fosfomycin is another alternative.35 Based on results ant, particularly when disease onset is after a long of susceptibility testing, nitrofurantoin, amoxicillin hospital admission with prior antibacterial therapy, or a cephalosporin can be used to treat UTIs in preg- and further resistance can emerge on treatment.
nant women36, but nitrofurantoin should not be given Pneumonia with S. aureus, particularly methicillin- near term or during labor or delivery because it can resistant strains, is also more common in patients with diabetes mellitus, head trauma, or intensive care unitadmission. Hospital-acquired pneumonia due to Acute uncomplicated pyelonephritis can often be
Legionella species can also occur, usually in immuno- managed with a 7-10 day course of ciprofloxacin or In the absence of risk factors for multi-drug resistant Complicated UTIs that recur after treatment, occur in
organisms, initial empiric therapy for hospital-acquired patients with indwelling urinary catheters, or are acquired in hospitals or nursing homes, are more like- biotic, such as ceftriaxone, a fluoroquinolone (levo- ly to be due to antibiotic-resistant gram-negative bacil- floxacin or moxifloxacin) or piperacillin/tazobactam. In li, S. aureus or enterococci. A fluoroquinolone, oral other patients, however, particularly those who are amoxicillin/clavulanate or an oral third-generation severely ill or in an ICU, broader-spectrum coverage cephalosporin such as cefpodoxime, cefdinir or with a beta-lactam with antipseudomonal activity such as ceftibuten can be useful in treating such infections in piperacillin/tazobactam, cefepime, imipenem, doripen- outpatients. In hospitalized patients with complicated em or meropenem, combined with a fluoroquinolone UTIs, treatment with a third-generation cephalosporin, with antipseudomonal activity (ciprofloxacin or lev- a fluoroquinolone, ticarcillin/clavulanate, piperacillin/ ofloxacin) would be a reasonable choice. Addition of tazobactam, imipenem, doripenem or meropenem is vancomycin or linezolid should be considered in hospi- tals where MRSA are common. Multi-drug resistantgram-negative bacteria, particularly Acinetobacter spp., PROSTATITIS — Acute bacterial prostatitis may be
Pseudomonas spp. and Klebsiella spp., are increasingly due to enteric gram-negative bacteria, especially E. coli common. Treatment options are often limited, but iso- Klebsiella spp., or to P. aeruginosa lates may be susceptible to polymyxin B, colistin Enterococcus spp.,38 but a bacterial pathogen is often (polymyxin E) or tigecycline; some Acinetobacter not identified. Occasionally, a sexually transmitted strains are also sensitive to sulbactam.
organism such as N. gonorrhoeae, Chlamydia tra-chomatis or Ureaplasma urealyticum is responsible.
INFECTIONS OF THE GENITOURINARY
Chronic bacterial prostatitis, although often idiopathic, may be caused by the same bacteria as acute prostatitis,or by S. aureus or coagulase-negative staphylococci.39 URINARY TRACT INFECTION (UTI) — E. coli
causes most uncomplicated cystitis. Staphylococcus
An oral fluoroquinolone with activity against P. aerug- saprophyticus is the second most common pathogen, inosa (ciprofloxacin or levofloxacin) is a reasonable and the remaining cases are due to Proteus spp., other choice for initial treatment of acute bacterial prostatitis in a patient who does not require hospitalization.
Trimethoprim/sulfamethoxazole could be used as an Although fluoroquinolones (especially ciprofloxacin) alternative. Fluoroquinolones are no longer recom- Treatment Guidelines from The Medical Letter • Vol. 8 ( Issue 94) • June 2010
Drugs for Bacterial Infections
mended for treatment of N. gonorrhoeae; if gonorrhea the causative organism and the immune status of the is suspected, IV ceftriaxone is recommended.40 patient. The choice should also reflect local patterns ofbacterial resistance.45 For more severe prostatitis, an IV fluoroquinolone orthird-generation cephalosporin may be used. Prostatic A third- or fourth-generation cephalosporin (cefotaxime, abscesses may require drainage in addition to antimi- ceftizoxime, ceftriaxone, ceftazidime or cefepime), crobial treatment. Chronic bacterial prostatitis is gener- piperacillin/tazobactam, ticarcillin/clavulanate, imipen- ally treated with a long (4-12 week) course of an oral em, meropenem, doripenem or aztreonam can be used to fluoroquinolone or trimethoprim/sulfamethoxazole.
treat sepsis caused by most strains of gram-negativebacilli. Among the cephalosporins, ceftazidime has less INTRA-ABDOMINAL INFECTIONS
activity against gram-positive cocci and cephalosporinsother than ceftazidime and cefepime have limited activi- Most intra-abdominal infections, such as cholangitis and
ty against P. aeruginosa. Piperacillin/tazobactam, diverticulitis, are due to enteric gram-negative organ-
imipenem, doripenem and meropenem are active against isms, most commonly E. coli, but also Klebsiella or most strains of P. aeruginosa and are active against Proteus spp. Enterococci and anaerobes, particularly anaerobes. Aztreonam is active against many strains of P. Bacteroides fragilis, are also common. Changes in bowel aeruginosa, but has no activity against gram-positive flora, such as occur in hospitalized patients treated with antibiotics, lead to an increased risk of infections due toPseudomonas and Candida spp. Many intra-abdominal For initial treatment of life-threatening sepsis in adults, infections, particularly abscesses, are polymicrobial.
a third- or fourth-generation cephalosporin (cefo-taxime, ceftriaxone, ceftazidime or cefepime), Empiric therapy should cover both aerobic and anaer- piperacillin/tazobactam, imipenem, doripenem or obic enteric gram-negative organisms. For communi- meropenem, each plus vancomycin, is recommended.
ty-acquired infection of mild to moderate severity, Some experts would add an aminoglycoside or a fluo- monotherapy with piperacillin/tazobactam, ertapen- roquinolone for a brief period (2-3 days).46,47 em, imipenem or meropenem would be a reasonablefirst choice.41 Cefotetan is an alternative. A fluoro- When bacterial endocarditis is suspected and therapy
quinolone such as moxifloxacin, or tigecycline alone9 must be started before the pathogen is identified, a can be used in patients allergic to beta-lactams. In combination of ceftriaxone and vancomycin can be severely ill patients and those with prolonged hospi- used. Many Medical Letter consultants would also add talization, treatment should include coverage for low-dose gentamicin to cover the 5% of cases caused Pseudomonas. Reasonable choices would include an antipseudomonal penicillin (piperacillin/tazobactam)or a carbapenem (imipenem, meropenem or doripen- Recombinant human activated protein C (Xigris) is occasionally used in combination with standard therapy ciprofloxacin, each plus metronidazole for B. fragilis for treatment of severe sepsis. Its use should be limited to adult patients with severe sepsis and evidence of dys-function in more than one organ, and with no bleeding Clostridium difficile is the most common identifiable cause of antibiotic-associated diarrhea. In recentyears, a more toxic epidemic strain has emerged, FEVER AND NEUTROPENIA — Selection of
causing an increase in the incidence and severity of antibacterials in patients with febrile neutropenia is C. difficile–infection (CDI).42 Oral metronidazole
usually made with little information about a causative can be used to treat mild or moderate CDI. Patients organism.49 Gram-positive bacteria account for the with severe disease and those with delayed response majority of microbiologically confirmed infections in to metronidazole should be treated with oral van- patients with neutropenia (especially in patients with comycin. First recurrences of CDI can be treated with central venous catheters), but enteric gram negative either metronidazole or vancomycin, but for multiple organisms and Pseudomonas spp. also occur, and the recurrences, longer courses of oral vancomycin with origins of infection (e.g. neutropenic enteritis) are slow tapering or pulsed doses should be used.43,44 SEPSIS SYNDROME
For empiric treatment of fever in patients with neu-tropenia, ceftazidime, piperacillin/tazobactam, imipen- For treatment of sepsis syndromes, the choice of drugs em, doripenem, meropenem or cefepime would be a should be based on the probable source of infection, reasonable first choice, with or without an aminogly- Treatment Guidelines from The Medical Letter • Vol. 8 ( Issue 94) • June 2010
Drugs for Bacterial Infections
Table 2. Some Generic and Brand Names
Some Brand and Generic Names
Treatment Guidelines from The Medical Letter • Vol. 8 ( Issue 94) • June 2010
Drugs for Bacterial Infections
coside. Addition of vancomycin may be necessary for treatment of neutropenic patients who remain febrile despite antibiotics or who may have bacteremia caused by methicillin-resistant staphylococci or penicillin- resistant viridans streptococci. When the response to antibacterials is poor, the possibility of fungemia, especially with Candida spp., should be considered.
Studies in low-risk hospitalized adults show that when neutropenia is expected to last less than 10 days, oral ciprofloxacin with amoxicillin/clavulanate is as effec- tive as intravenous ceftazidime or ceftriaxone plus MULTIPLE-ANTIBIOTIC-RESISTANT ENTE-
ROCOCCI — Many Enterococcus spp., particularly
E. faecium, are now resistant to penicillin and ampi- cillin, to gentamicin or streptomycin or both, and to vancomycin. Some of these strains are susceptible in 22. Committee on Infectious Diseases in LK Pickering eds, 2009 Red Book: vitro to chloramphenicol, doxycycline or, rarely, to Report of the Committee on Infectious Diseases 28th ed, Evanston III: fluoroquinolones, but clinical results with these drugs American Academy of Pediatrics 2009, page 528.
have been variable. Linezolid, daptomycin and tigecy- cline are active against many gram-positive organisms, including both E. faecium and E. faecalis; resistance to these drugs has been relatively rare. Quinupristin/dalfo- pristin, which is not commonly used because of its tox- icity and drug interactions, is active against most strains of vancomycin-resistant E. faecium, but not E. fae- calis.53 Polymicrobial surgical infections that include antibiotic-resistant enterococci may respond to antibi- otics aimed at the other organisms. When antibiotic- resistant enterococci cause endocarditis, surgical replacement of the infected valve may be required.
UTIs caused by resistant enterococci may respond nev- ertheless to ampicillin or amoxicillin, which reach very high concentrations in urine; nitrofurantoin or fos- Treatment Guidelines from The Medical Letter • Vol. 8 ( Issue 94) • June 2010
Drugs for Bacterial Infections
Coming Soon in Treatment Guidelines:
Drugs for Sexually Transmitted Infections – July Drugs for Psychotic Disorders – August 2010 EDITOR IN CHIEF: Mark Abramowicz, M.D.
EDITOR IN CHIEF:
EXECUTIVE EDIT Mark Abramo
Mark Abramo
Gianna Zuccotti
, M.D., M.P.H., F.A.C.P., Harvard Medical EXECUTIVE EDIT
EXECUTIVE EDIT
Gianna Zuccotti, M.D., M.P
Jean-Marie Pflomm, Pharm.D.
ASSIST Jean-Marie Pflomm
ANT EDITORS, DR
Jean-Marie Pflomm
UG INFORMATION: Susan M. Daron, Pharm.D.,
ASSISTANT EDIT
Blaine M. Houst OR,
UG INFORMA
m.D., Corinne E.TION:
UG INFORMA
Susan More
Zanone, Pharm.D. y
Susan More , Phar
CONTRIBUTING EDIT
UTING EDIT
Eric J Epstein, M.D
, M.D Albert Einstein College of Medicine CONSULTING EDITOR: Brinda M. Shah, Pharm.D.
CONTRIBUTING EDIT
UTING EDIT
DRUG INTERA
UG INTERA
Philip D.
Philip D Hansten, Pharm.D.,
Y BO ashington
ules Hir Y BO
VISORsch
Jules Hir
Gerald L.
Mandell ., Roc
Dan M. Roden, M.D., Vanderbilt University School of Medicine
Juurlink,
CONTRIB Kim,
Kim M.D., Univ
UTING EDIT
Gerald L.
Bazil, M.D, M.D
., Columbia University College of Physicians and Surgeons Hans Meiner
Vanessa K. tz, M.D
Dalton ., Univ
., M.P.H., University of Michigan Medical School Eric J. Roden
Epstein, M.D.,
F Estelle R.
David N. J
uurlink,
., PhD, Sunnybrook Health Sciences Centre Richar Steigbig
d B. Kim, el
Steigbig , M.D
SENIOR ASSOCIA
Hans Meinertz
SENIOR ASSOCIA
, M.D., Univ ORS:
Donna Goodstein, Am
ersity Hospital, Copenhagen y F
ASSOCIATE EDIT
Sandip K.
Mukherjee, Cynthia Macapa
M.D., F.A.C.C., Y gal Co
Cynthia Macapa
ORIAL FELLO
Estelle R.
ORIAL FELLO
W, M.D., University of Manitoba
Lauren K.
Jordan W.Schwar
Smoller, , M.D
tzM.D ., Mount Sinai School of Medicine
PRODUCTION COORDINA
Neal H. Steigbigel, M.D
ODUCTION COORDINA
w Yor Cheryl Br
ASSISTANT MANA
GING EDIT
GING EDIT
Liz Donohue
SENIOR ASSOCIATE EDITORS: Donna Goodstein, Amy Faucard
MANAGING EDIT
GING EDIT
Susie ong
ASSOCIATE EDITOR: Cynthia Macapagal Covey
EDITORIAL FELLOW: Vince Teo B.Sc. Phm, Sunnybrook Health Sciences Centre
EXECUTIVE DIRECTOR OF SALES:
EXECUTIVE DIRECT
Gene Carbona
FULFILLMENT AND SYSTEMS MANA
MANAGING EDITOR: Susie Wong
FULFILLMENT AND SYSTEMS MANA
Cristine Romatowski
Cristine Romato
ASSISTOR OF MARKETING COMMUNICA
DIRECTANT MANAGING EDITOR:
OR OF MARKETING COMMUNICA
Liz Donohue
Joanne F.
Joanne F Valentino
VICE PRESIDENT AND PUBLISHER:
PRODUCTION COORDINATOR: CherYosef
yl BroWissner
EXECUTIVE DIRECTOR OF SALES: Gene Carbona
FULFILLMENT AND SYSTEMS MANAGER:
Cristine Romatowski
OR OF MARKETING COMMUNICATIONS:
Joanne F. Valentino
VICE PRESIDENT AND PUBLISHER: Yosef Wissner-Levy
Copyright and Disc
yright and Disc
The Medical Letter is an independent nonprofit organ- Copyright and Disclaimer: The Medical Letter is an independent nonprofit organ-
ommendations The editorial process used for its pub ization that provides healthcare professionals with unbiased drug prescribing rec- , with an emphasis on controlled clinical tr ommendations. The editorial process used for its publications relies on a review of and on the opinions of its consultants.
and on the opinions of its consultants The Medical Letter is supported solely by sub- published and unpublished literature, with an emphasis on controlled clinical trials, and on the opinions of its consultants. The Medical Letter is supported solely by sub-scription fees and accepts no advertising, grants or donations.
No part of the material may be reproduced or transmitted by any process in whole or in part without prior permission in writing. The editors do not warrant that all the mate- rial in this publication is accurate and complete in every respect. The editors shall notbe held responsible for an Subscription Services
y damage resulting from any error, inaccuracy or omission.
Mailing Address:
Mailing Ad
Subscription SerSubscriptions (US):
Mailing Address:
Subscriptions (US):
3 years - $235. $49/yr. for students,US and Canada.
Customer Service:
interns, residents and fellows in theCME: $44 for 26 credits.
Customer Service:
Fax: 914-632-1733
E-mail site license inquiries to:
Call: 800-211-2769 or 914-235-0500Web Site: www E-mail site license inquiries to:
[email protected] or callSpecial fees for bulk subscriptions.
Permissions:
800-211-2769 x315.
Special classroom rates ar Special fees for bulk subscriptions.
Permissions:
Treatment Guidelines from The Medical Letter • Vol. 8 ( Issue 94) • June 2010
Introducing
Treatment Guidelines: Online Continuing Medical Education Up to 24 credits included with your subscription For over 25 years, The Medical Letter has offered health care professionals continuing medical education (CME) with The Medical Letter on Drugs andTherapeutics. We are now offering CME for Treatment Guidelines from The Medical Letter in an online format only, called the Online Series. Each OnlineSeries is comprised of 6 monthly exams and eligible for up to 12 credits. For those who just need a few credits, we also offer the Quick Online Credit Exam(earn up to 2 credits/12 questions). For more information, please visit us at www.medicalletter.org/tgcme.
Choose CME from Treatment Guidelines from The Medical Letter and earn up to
24 Category 1 Credits per year in the format that’s right for you:
Online Series - Answer 12 questions per issue online. Earn up to 2 credits/exam. Take up to 6 short exams per six-month series and earn up to a total of
12 credits. The Online Series is included with a paid subscription to Treatment Guidelines.
Quick Online Credit Exam - Access content for any available issue, answer 12 questions online, and earn up to 2 credits for $12.00 (available to both sub-
scribers and non-subscribers).
ACCREDITATION INFORMATION:
ACCME: The Medical Letter is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.
The Medical Letter designates this educational activity for a maximum of 2 AMA PRA Category 1 Credit(s)™. Physicians should only claim credit com-
mensurate with the extent of their participation in this activity. This CME activity was planned and produced in accordance with the ACCME Essentials.
AAFP: Treatment Guidelines from The Medical Letter has been reviewed and is acceptable for up to 15 Prescribed credits by the American Academy of
Family Physicians. AAFP accreditation begins 01/01/09. Term of approval is for one year from this date. This exam is approved for 1.25 Prescribed cred-
its. Credits may be claimed for one year from the date of this exam.
ACPE: The Medical Letter is accredited by the Accreditation Council for Pharmacy Education as a provider of continuing pharmacy education. This issue
is acceptable for 2.0 hours of Continuing Education Credit (0.2 CEU).
AANP and AAPA: The American Academy of Nurse Practitioners (AANP) and the American Academy of Physician Assistants (AAPA) accept AMA
Category 1 Credit for the Physician’s Recognition Award from organizations accredited by the ACCME.
AOA: This activity, being ACCME (AMA) approved, is acceptable for Category 2-B credit by the American Osteopathic Association.
MISSION:
The mission of The Medical Letter's Continuing Medical Education Program is to support the professional development of health care professionals includ-
ing physicians, nurse practitioners, pharmacists and physician assistants by providing independent, unbiased drug information and prescribing recom-
mendations that are free of industry influence. The program content includes current information and unbiased reviews of FDA-approved and off-label uses
of drugs, their mechanisms of action, clinical trials, dosage and administration, adverse effects and drug interactions. The Medical Letter delivers educa-
tional content in the form of self-study material.
The expected outcome of the CME Program is that knowledge and consideration of the information contained in The Medical Letter and TreatmentGuidelines can affect health care practice and ultimately result in improved patient care and outcomes.
The Medical Letter will strive to continually improve the CME program through periodic assessment of the program and activities. The Medical Letter aimsto be a leader in supporting the professional development of health care professionals by providing continuing medical education that is unbiased and freeof industry influence.
LEARNING OBJECTIVES:
The objective is to meet the need of health care professionals for unbiased, reliable and timely information on treatment of major diseases.
Activity participants will read and assimilate unbiased reviews of FDA-approved and off-label uses of drugs and drug classes. Participants will be able toselect and prescribe, or confirm the appropriateness of the prescribed usage of the drugs and other therapeutic modalities discussed in TreatmentGuidelines with specific attention to clinical evidence of effectiveness, adverse effects and patient management. Through this program, The MedicalLetter expects to provide the prescribing health care community with educational content that they will use to make independent and informed therapeu-tic choices in their practice.
Privacy and Confidentiality: The Medical Letter guarantees our firm commitment to your privacy. We do not sell any of your information. Secure server software (SSL)
is used for commerce transactions through VeriSign, Inc. No credit card information is stored.
IT Requirements: Windows 98/NT/2000/XP/Vista/7, Pentium+ processor, Mac OS X+ w/ compatible process; Microsoft IE 6.0+, Mozilla Firefox 2.0+ or any other com-
patible Web browser. Dial-up/high-speed connection.
Have any questions? Call us at 800-211-2769 or 914-235-0500 or e-mail us at: [email protected]
Questions start on next page
Treatment Guidelines from The Medical Letter • Vol. 8 ( Issue 94) • June 2010
DO NOT FAX OR MAIL THIS EXAM
To take this exam, go to:
Issue 94 Questions
1. Uncomplicated skin and skin structure infections are commonly 7. The drug of choice to treat acute pharyngitis is: 8. In severely ill patients with hospital-acquired pneumonia, 2. Methicillin-resistant Staphylococcus aureus (MRSA) therapy should include a fluoroquinolone combined with: 9. A pregnant woman in her last week of pregnancy with 3. The most common cause of acute osteomyelitis is: a urinary tract infection should not be treated with: 4. Antibacterial therapy in patients with chronic osteomyelitis is 10. Mild or moderate C. difficile-infection can be treated with: 11. Therapy for sepsis syndrome should be based on: 5. Meningitis caused by Listeria monocytogenes is more 12. Which of the following is active against both E. faecium 6. Dexamethasone may be added to therapy in children with bacterial meningitis to decrease the risk of: ACPE UPN: 379-000-10-094-H01-P; Release: June 2010, Expire: June 2011
Treatment Guidelines from The Medical Letter • Vol. 8 ( Issue 93) • May 2010

Source: http://gorgas.dom.uab.edu/syllabus/2011/07_Bacteria/RxBacteriaMed_lett.pdf