Correspondence
Correction
Staphylococcus aureus Infections
N Engl J Med 1998; 339:2025-2027December 31, 1998
- Article
To the Editor:
In his review of Staphylococcus aureus infections, Dr. Lowy (Aug. 20 issue)1 states that bacteremia involving methicillin-resistant Staphylococcus aureus (MRSA) is not associated with higher mortality than bacteremia involving methicillin-susceptible S. aureus (MSSA). However, Romero-Vivas et al.,2 who conducted the largest study, noted a significantly higher fatality rate among patients with MRSA bacteremia. In their comparison of 100 cases of MSSA bacteremia and 84 cases of MRSA bacteremia, the mortality rates were 32 percent and 58.3 percent, respectively (P<0.01), and using stepwise logistic-regression analysis, they found that methicillin resistance was independently associated with mortality. More recently, Conterno et al.3 also reported methicillin resistance as a risk factor for a poor outcome in patients with S. aureus bacteremia.
Two important factors indicate the need for caution when interpreting the results of comparative analyses of MRSA bacteremia and MSSA bacteremia.
The first problem concerns demographic differences. Patients with MRSA bacteremia are often older than those with MSSA bacteremia and are likely to have a longer hospital stay. They are also likely to have had a longer hospital stay and greater use of antibiotics before the development of bacteremia. The second problem is that, in all these analyses, the severity of the illness was not classified. When one compares mortality rates, accurate adjustment for severity of illness is desirable, if not necessary.
We investigated the outcome in critically ill patients with S. aureus bacteremia.4 In a retrospective study, we compared 35 cases of MSSA bacteremia with 40 cases of MRSA bacteremia. Adjustment for severity of illness was made on the basis of the Acute Physiology and Chronic Health Evaluation (APACHE II) score.5 Our results confirm those of the authors cited above. The in-hospital mortality rate in the group of patients with MRSA bacteremia was 65 percent, as compared with 25.7 percent in the MSSA group (P<0.001). Even after the patients had been matched for the APACHE II score (n=44), the mortality rate was twice as high among those with MRSA bacteremia (P<0.001). Logistic-regression analysis showed that methicillin resistance and an unfavorable APACHE II score were independent risk factors for death (P<0.001).
5 ReferencesStijn Blot, R.N., M.A.
Koenraad Vandewoude, M.D.
Francis Colardyn, M.D.
Universitair Ziekenhuis Gent, B-9000 Ghent, Belgium1
Lowy FD . Staphylococcus aureus infection. N Engl J Med 1998;339:520-532
Full Text | Web of Science | Medline2
Romero-Vivas J ,Rubio M ,Fernandez C ,Picazo JJ . Mortality associated with nosocomial bacteremia due to methicillin-resistant Staphylococcus aureus. Clin Infect Dis 1995;21:1417-1423
CrossRef | Web of Science | Medline3
Conterno LO ,Wey SB ,Castelo A . Risk factors for mortality in Staphylococcus aureus bacteremia. Infect Control Hosp Epidemiol 1998;19:32-37
CrossRef | Web of Science | Medline4
Blot S ,Vandewoude K ,Hoste E ,Danneels C ,Colardyn F . Outcome in bacteremia with methicillin-resistant and methicillin-susceptible Staphylococcus aureus. Intensive Care Med 1998;24:Suppl:S173-S173 abstract.5
Knaus WA ,Draper EA ,Wagner DP ,Zimmerman JE . APACHE II: a severity of disease classification system. Crit Care Med 1985;13:818-829
CrossRef | Web of Science | Medline
To the Editor:
In his excellent review of S. aureus infections, Lowy discusses antimicrobial therapy for this bacterial pathogen. Although experimental therapies such as quinupristin–dalfopristin are noted, the author does not mention teicoplanin. A glycopeptide antibiotic structurally related to vancomycin,1 teicoplanin is widely used in Europe but has not been approved for use in the United States.
Teicoplanin has some advantages over vancomycin.1 The toxicity profile of teicoplanin is more favorable, especially when it is used with other potentially toxic drugs, since nephrotoxicity and ototoxicity are relatively uncommon. Teicoplanin also has an advantage in terms of ease of administration. It can be given once daily, either intravenously or intramuscularly, and by rapid intravenous injection.1 With teicoplanin, there is no need for routine blood-level monitoring, making it easier to use outside the hospital.2 Moreover, teicoplanin and vancomycin have similar activity against S. aureus 3 and similar clinical efficacy.4 The combination of these factors makes teicoplanin an effective, safe alternative to vancomycin in the treatment of S. aureus infections.1,4
4 ReferencesAlicia Conde, M.D., Ph.D.
Hospital El Sabinal, 35017 Las Palmas, Spain1
Shea KW ,Cunha BA . Teicoplanin. Med Clin North Am 1995;79:833-844
Web of Science | Medline2
Gruneberg RN . Anti-gram-positive agents: what we have and what we would like. Drugs 1997;54:Suppl 6:29-38
CrossRef | Web of Science | Medline3
Greenwood D . Microbiological properties of teicoplanin. J Antimicrob Chemother 1998;21:Suppl A:1-134
Wood MJ . The comparative efficacy and safety of teicoplanin and vancomycin. J Antimicrob Chemother 1996;37:209-222[Erratum, J Antimicrob Chemother 1996;38:919; J Antimicrob Chemother 1997;40:147.]
CrossRef | Web of Science | Medline
To the Editor:
In his splendid review of S. aureus infections, Lowy discusses life-threatening infections. Although he states that patients with human immunodeficiency virus (HIV) infection are at increased risk for staphylococcal colonization, he does not detail the peculiar characteristics of this infection in such patients. S. aureus pneumonia has been reported to occur in HIV-infected patients at a frequency exceeding that in the general population.1
We conducted a retrospective case–control study in the department of infectious diseases of a 1700-bed university hospital in Rome. For the period from 1986 through 1997, we identified 350 episodes of bacterial pneumonia (as defined elsewhere2) and 28 episodes of S. aureus pneumonia. The attack rate for S. aureus pneumonia was 8.31 cases per 1000 HIV-related hospital admissions. S. aureus pneumonia was a community-acquired infection in two thirds of the HIV-positive patients, a finding at variance with the frequently reported finding that in immunocompetent patients, a nosocomial origin of S. aureus pneumonia is more common.
In conclusion, we emphasize the importance of S. aureus as an etiologic agent of life-threatening pulmonary infections in HIV-positive persons. Although other microorganisms can cause pneumonia, HIV-positive patients who have an acute onset with lobar involvement and pleural effusion on chest radiography should be carefully evaluated for the possibility of S. aureus pneumonia.
2 ReferencesEvelina Tacconelli, M.D.
Mario Tumbarello, M.D.
Roberto Cauda, M.D.
Università Cattolica Sacro Cuore, 00168 Rome, Italy1
Tumbarello M ,Tacconelli E ,Lucia MB ,Cauda R ,Ortona L . Predictors of Staphylococcus aureus pneumonia associated with human immunodeficiency virus infection. Respir Med 1996;90:531-537
CrossRef | Web of Science | Medline2
Tumbarello M ,Tacconelli E ,de Gaetano K , et al. Bacterial pneumonia in HIV-infected patients: analysis of risk factors and prognostic indicators. J Acquir Immune Defic Syndr Hum Retrovirol 1998;18:39-45
CrossRef | Medline
Author/Editor Response
Dr. Lowy replies:
To the Editor: Blot et al. cite several studies suggesting that the outcome of infections caused by MRSA is worse than that of infections caused by MSSA. Other reports argue against the greater virulence of MRSA strains.1,2 As Blot et al. note, these studies must be interpreted cautiously, because of the frequent association of MRSA infections with a greater severity of illness, an underlying disease of a different nature, prolonged hospitalization, and increased antibiotic use. These variables make comparative analyses difficult, especially for retrospective studies. The virulence of staphylococcal infection may be more closely tied to particular strains than to the presence or absence of methicillin resistance.
As Dr. Conde suggests, teicoplanin was not mentioned because it is not available in the United States. Although it has some pharmacologic advantages, teicoplanin has been reported to have less antistaphylococcal activity than vancomycin, or at best, similar activity.3
Tacconelli et al. describe an important presentation of staphylococcal disease in HIV-positive patients. The incidence of staphylococcal disease in general appears to be increased in this population. There have also been reports of an increased incidence of bloodstream, skin, and soft-tissue infections, as well as respiratory tract infections.4,5 The basis of these infections is uncertain, but it may be related to the immunocompromised status of the patients, an increased colonization rate, and the use of more frequent invasive procedures that breach skin or mucosal barriers.
There is an error on page 520 of my article (first column, last paragraph, second line). The size of the chromosome should be 2.8 megabase pairs, not 2800 base pairs.
5 ReferencesFranklin D. Lowy, M.D.
Montefiore Medical Center, Bronx, NY 104671
French GL ,Cheng AF ,Ling JM ,Mo P ,Donnan S . Hong Kong strains of methicillin-resistant and methicillin-sensitive Staphylococcus aureus have similar virulence. J Hosp Infect 1990;15:117-125
CrossRef | Web of Science | Medline2
Harbath S ,Rutschmann O ,Sudre P ,Pittet D . Impact of methicillin resistance on the outcome of patients with bacteremia caused by Staphylococcus aureus. Arch Intern Med 1998;158:182-189
CrossRef | Web of Science | Medline3
Chambers HF. Parenteral antibiotics for the treatment of bacteremia and other serious staphylococcal infections. In: Crossley KB, Archer GL, eds. The staphylococci in human disease. New York: Churchill Livingstone, 1997:583-601.
4
Weinke T ,Schiller R ,Fehrenbach FJ ,Pohle HD . Association between Staphylococcus aureus nasopharyngeal colonization and septicemia in patients infected with human immunodeficiency virus. Eur J Clin Microbiol Infect Dis 1992;11:985-989
CrossRef | Web of Science | Medline5
Krumholz HM ,Sande MA ,Lo B . Community-acquired bacteremia in patients with acquired immunodeficiency syndrome: clinical presentation, bacteriology, and outcome. Am J Med 1989;86:776-779
CrossRef | Web of Science | Medline
- Citing Articles (6)
Citing Articles
1
Harald Seifert, Hilmar Wisplinghoff. 2010. Bloodstream Infection and Endocarditis. .
CrossRef2
Marco Cassone, Floriana Campanile, Annalisa Pantosti, Mario Venditti, Stefania Stefani. (2004) Identification of a Variant "Rome Clone" of Methicillin-Resistant Staphylococcus aureus with Decreased Susceptibility to Vancomycin, Responsible for an Outbreak in an Intensive Care Unit. Microbial Drug Resistance 10:1, 43-49
CrossRef3
Stijn Blot, Koenraad Vandewoude, Dirk De Bacquer, Francis Colardyn. (2002) Nosocomial Bacteremia Caused by Antibiotic‐Resistant Gram‐Negative Bacteria in Critically Ill Patients: Clinical Outcome and Length of Hospitalization. Clinical Infectious Diseases 34:12, 1600-1606
CrossRef4
Hilmar Wisplinghoff, Harald Seifert, Marcus Coimbra, Richard P. Wenzel, Michael B. Edmond. (2001) Systemic Inflammatory Response Syndrome in Adult Patients with Nosocomial Bloodstream Infection Due to Staphylococcus aureus. Clinical Infectious Diseases 33:5, 733-736
CrossRef5
Barry M. Farr. (2000) Reasons for Noncompliance With Infection Control Guidelines • . Infection Control and Hospital Epidemiology 21:6, 411-416
CrossRef6
Barry M. Farr. (1999) Methicillin-resistant Staphylococcus aureus infections. Current Infectious Disease Reports 1:4, 328-333
CrossRef
