Cellulitis
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《新英格兰医药杂志》
To the Editor: In his review of cellulitis (Feb. 26 issue),1 Swartz does not stress the effect that the emergence of community-acquired methicillin-resistant Staphylococcus aureus has had on treatment strategies for a "usual case of cellulitis" at many centers in the United States and elsewhere.2,3,4 Methicillin-resistant S. aureus strains circulating among previously healthy persons in the community attending our medical center now constitute the majority of S. aureus isolates, and we have terminated our reliance on beta-lactams as initial therapy for putative community-acquired cellulitis due to infection with the resistant strain — the therapy Swartz suggests. We now use clindamycin for the initial treatment of "usual" cellulitis while susceptibility and D-test data5 are gathered; we use vancomycin for critically ill patients with putative S. aureus infection. Others use linezolid or trimethoprim–sulfamethoxazole as initial therapy.
Although this rapidly spreading problem may not yet have reached all geographic locales, there may be real consequences from the "business as usual" approach Swartz recommends. Delay in the use of non–beta-lactam antimicrobial therapy for methicillin-resistant S. aureus infection was believed to have contributed to the deaths from severe sepsis due to community-acquired methicillin-resistant S. aureus in Minnesota and North Dakota.6
Samuel R. Dominguez, M.D., Ph.D.
John F. Marcinak, M.D.
Robert S. Daum, M.D.
University of Chicago
Chicago, IL 60637-1470
rdaum@peds.bsd.uchicago.edu
References
Swartz MN. Cellulitis. N Engl J Med 2004;350:904-912.
Herold BC, Immergluck LC, Maranan MC, et al. Community-acquired methicillin-resistant Staphylococcus aureus in children with no identified predisposing risk. JAMA 1998;279:593-598.
Naimi TS, Ledell KH, Boxrud DJ, et al. Epidemiology and clonality of community-acquired methicillin-resistant Staphylococcus aureus in Minnesota, 1996-1998. Clin Infect Dis 2001;33:990-996.
Vandenesch F, Naimi T, Enright MC, et al. Community-acquired methicillin-resistant Staphylococcus aureus carrying Panton-Valentine leukocidin genes: worldwide emergence. Emerg Infect Dis 2003;9:978-984.
Weisblum B, Demohn V. Erythromycin-inducible resistance in Staphylococcus aureus: survey of antibiotic classes involved. J Bacteriol 1969;98:44-52.
Four pediatric deaths from community-acquired methicillin-resistant Staphylococcus aureus -- Minnesota and North Dakota, 1997-1999. MMWR Morb Mortal Wkly Rep 1999;48:707-710.
To the Editor: If both S. aureus and hemolytic streptococci are likely causes of recurrent cellulitis, why should initial therapy be with antistaphylococcal beta-lactams but prophylaxis only with penicillin? What is the justification for routine parenteral therapy for patients with a temperature above 100.5°F (38.1°C) when highly bioavailable drugs that are not concentration-dependent are available?1
Edward L. Goodman, M.D.
Presbyterian Hospital of Dallas
Dallas, TX 75231
edwardgoodman@texashealth.org
References
Moellering RC. Linezolid: the first oxazolidinone antimicrobial. Ann Intern Med 2003;138:135-142. [Abstract/Full Text]
To the Editor: Swartz mentions the prophylactic use of penicillin G for patients who, despite other measures, have frequent episodes of cellulitis or more than two episodes at the same site. However, penicillin G potassium is no longer commercially available for use by the oral route in the United States. The penicillin that is currently used for prophylaxis against cellulitis by the oral route is penicillin V potassium, since it has better resistance to acid-catalyzed inactivation after oral administration.1
Hernan R. Chang, M.D.
P.O. Box 17577
Jacksonville, FL 32245-7577
hrc8@hotmail.com
References
Wright AJ, Wilkowske CJ. The penicillins. Mayo Clin Proc 1991;66:1047-1063.
Dr. Swartz replies: Dr. Dominguez and colleagues rightly stress the emergence of community-acquired methicillin-resistant S. aureus at their center, elsewhere in the United States, and abroad — a concern I note in my article. As a consequence, they recommend clindamycin for the initial treatment of the usual case of cellulitis. Most cellulitides are not associated with a subcutaneous abscess or initiating site that can be sampled for Gram's staining or culture for a presumptive bacteriologic diagnosis. Bacteriologic results from the examination of needle aspirates, punch-biopsy specimens, or blood cultures from patients with cellulitis have indicated that approximately 80 percent of the pathogens are gram-positive organisms.1
At this time, I do not recommend clindamycin as initial therapy, for several reasons. First, at least 40 to 50 percent of gram-positive pathogens in cellulitis are streptococci that are highly susceptible to beta-lactams and cephalosporins, which are very effective against them clinically. Second, at my hospital, 5 to 11 percent of non–group A streptococci are resistant to clindamycin. Third, the frequency of infection with community-acquired methicillin-resistant S. aureus varies substantially among locales. Among Minnesota hospitals in 1998, 3 percent of 4302 S. aureus isolates were community-acquired methicillin-resistant strains.1 In Chicago between 1993 and 1995, 12 of 55 community-acquired S. aureus isolates associated with cellulitis (22 percent) were considered methicillin-resistant.2 This emphasizes the need for more population-based surveillance studies to inform initial antibiotic choices. Most laboratories do not routinely distinguish S. aureus isolates with respect to their community or nosocomial origins. A rough approximation might be provided by determining the frequency of the community-acquired methicillin-resistant phenotype (i.e., combined methicillin resistance and susceptibility to clindamycin) among all S. aureus isolates.
Dr. Goodman questions the choice of oral penicillin rather than antistaphylococcal beta-lactams for prophylaxis against recurrent cellulitis. Most such cases in which the cause is defined are due to streptococci, and evidence indicates that penicillin is effective. Antistaphylococcal beta-lactams are more expensive and less well tolerated with prolonged use. There are two reasons for the preference for parenteral over highly bioavailable drugs as initial therapy in patients with cellulitis and a temperature of 100.5°F or above: first, the rapidity with which cellulitis can spread and bacteremia ensue, and second, the more rapid and certain delivery of the drug when nausea and vomiting may occur unpredictably. However, as noted, studies are needed to determine which patients with mild cellulitis are likely to have a response to oral antibiotics. Finally, oral linezolid is listed (in Table 4 of my article) as treatment after initial parenteral therapy in cases in which methicillin-resistant S. aureus infection (nosocomial or community-acquired) is suspected.
As Dr. Chang points out, penicillin V potassium is now used in place of penicillin G potassium, which is no longer commercially available.
Morton N. Swartz, M.D.
Massachusetts General Hospital
Boston, MA 02114
mswartz@partners.org
References
Naimi TS, Ledell KH, Boxrud DJ, et al. Epidemiology and clonality of community-acquired methicillin-resistant Staphylococcus aureus in Minnesota, 1996-1998. Clin Infect Dis 2001;33:990-996.
Herold BC, Immergluck LC, Maranan MC, et al. Community-acquired methicillin-resistant Staphylococcus aureus in children with no identified predisposing risk. JAMA 1998;279:593-598.
Although this rapidly spreading problem may not yet have reached all geographic locales, there may be real consequences from the "business as usual" approach Swartz recommends. Delay in the use of non–beta-lactam antimicrobial therapy for methicillin-resistant S. aureus infection was believed to have contributed to the deaths from severe sepsis due to community-acquired methicillin-resistant S. aureus in Minnesota and North Dakota.6
Samuel R. Dominguez, M.D., Ph.D.
John F. Marcinak, M.D.
Robert S. Daum, M.D.
University of Chicago
Chicago, IL 60637-1470
rdaum@peds.bsd.uchicago.edu
References
Swartz MN. Cellulitis. N Engl J Med 2004;350:904-912.
Herold BC, Immergluck LC, Maranan MC, et al. Community-acquired methicillin-resistant Staphylococcus aureus in children with no identified predisposing risk. JAMA 1998;279:593-598.
Naimi TS, Ledell KH, Boxrud DJ, et al. Epidemiology and clonality of community-acquired methicillin-resistant Staphylococcus aureus in Minnesota, 1996-1998. Clin Infect Dis 2001;33:990-996.
Vandenesch F, Naimi T, Enright MC, et al. Community-acquired methicillin-resistant Staphylococcus aureus carrying Panton-Valentine leukocidin genes: worldwide emergence. Emerg Infect Dis 2003;9:978-984.
Weisblum B, Demohn V. Erythromycin-inducible resistance in Staphylococcus aureus: survey of antibiotic classes involved. J Bacteriol 1969;98:44-52.
Four pediatric deaths from community-acquired methicillin-resistant Staphylococcus aureus -- Minnesota and North Dakota, 1997-1999. MMWR Morb Mortal Wkly Rep 1999;48:707-710.
To the Editor: If both S. aureus and hemolytic streptococci are likely causes of recurrent cellulitis, why should initial therapy be with antistaphylococcal beta-lactams but prophylaxis only with penicillin? What is the justification for routine parenteral therapy for patients with a temperature above 100.5°F (38.1°C) when highly bioavailable drugs that are not concentration-dependent are available?1
Edward L. Goodman, M.D.
Presbyterian Hospital of Dallas
Dallas, TX 75231
edwardgoodman@texashealth.org
References
Moellering RC. Linezolid: the first oxazolidinone antimicrobial. Ann Intern Med 2003;138:135-142. [Abstract/Full Text]
To the Editor: Swartz mentions the prophylactic use of penicillin G for patients who, despite other measures, have frequent episodes of cellulitis or more than two episodes at the same site. However, penicillin G potassium is no longer commercially available for use by the oral route in the United States. The penicillin that is currently used for prophylaxis against cellulitis by the oral route is penicillin V potassium, since it has better resistance to acid-catalyzed inactivation after oral administration.1
Hernan R. Chang, M.D.
P.O. Box 17577
Jacksonville, FL 32245-7577
hrc8@hotmail.com
References
Wright AJ, Wilkowske CJ. The penicillins. Mayo Clin Proc 1991;66:1047-1063.
Dr. Swartz replies: Dr. Dominguez and colleagues rightly stress the emergence of community-acquired methicillin-resistant S. aureus at their center, elsewhere in the United States, and abroad — a concern I note in my article. As a consequence, they recommend clindamycin for the initial treatment of the usual case of cellulitis. Most cellulitides are not associated with a subcutaneous abscess or initiating site that can be sampled for Gram's staining or culture for a presumptive bacteriologic diagnosis. Bacteriologic results from the examination of needle aspirates, punch-biopsy specimens, or blood cultures from patients with cellulitis have indicated that approximately 80 percent of the pathogens are gram-positive organisms.1
At this time, I do not recommend clindamycin as initial therapy, for several reasons. First, at least 40 to 50 percent of gram-positive pathogens in cellulitis are streptococci that are highly susceptible to beta-lactams and cephalosporins, which are very effective against them clinically. Second, at my hospital, 5 to 11 percent of non–group A streptococci are resistant to clindamycin. Third, the frequency of infection with community-acquired methicillin-resistant S. aureus varies substantially among locales. Among Minnesota hospitals in 1998, 3 percent of 4302 S. aureus isolates were community-acquired methicillin-resistant strains.1 In Chicago between 1993 and 1995, 12 of 55 community-acquired S. aureus isolates associated with cellulitis (22 percent) were considered methicillin-resistant.2 This emphasizes the need for more population-based surveillance studies to inform initial antibiotic choices. Most laboratories do not routinely distinguish S. aureus isolates with respect to their community or nosocomial origins. A rough approximation might be provided by determining the frequency of the community-acquired methicillin-resistant phenotype (i.e., combined methicillin resistance and susceptibility to clindamycin) among all S. aureus isolates.
Dr. Goodman questions the choice of oral penicillin rather than antistaphylococcal beta-lactams for prophylaxis against recurrent cellulitis. Most such cases in which the cause is defined are due to streptococci, and evidence indicates that penicillin is effective. Antistaphylococcal beta-lactams are more expensive and less well tolerated with prolonged use. There are two reasons for the preference for parenteral over highly bioavailable drugs as initial therapy in patients with cellulitis and a temperature of 100.5°F or above: first, the rapidity with which cellulitis can spread and bacteremia ensue, and second, the more rapid and certain delivery of the drug when nausea and vomiting may occur unpredictably. However, as noted, studies are needed to determine which patients with mild cellulitis are likely to have a response to oral antibiotics. Finally, oral linezolid is listed (in Table 4 of my article) as treatment after initial parenteral therapy in cases in which methicillin-resistant S. aureus infection (nosocomial or community-acquired) is suspected.
As Dr. Chang points out, penicillin V potassium is now used in place of penicillin G potassium, which is no longer commercially available.
Morton N. Swartz, M.D.
Massachusetts General Hospital
Boston, MA 02114
mswartz@partners.org
References
Naimi TS, Ledell KH, Boxrud DJ, et al. Epidemiology and clonality of community-acquired methicillin-resistant Staphylococcus aureus in Minnesota, 1996-1998. Clin Infect Dis 2001;33:990-996.
Herold BC, Immergluck LC, Maranan MC, et al. Community-acquired methicillin-resistant Staphylococcus aureus in children with no identified predisposing risk. JAMA 1998;279:593-598.