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Variation in European antibiotic use
CORRESPONDENCE
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Stephenson J. Icelandic researchers are showing the way to bring down rates of antibiotic-resistant bacteria. JAMA 1996; 275: 175. Seppala H, Klaukka T, Vuopiio-Varkila J, et al. The effect of changes in the consumption of macrolide antibiotics on erythromycin resistance in group A streptococci in Finland. N Engl J Med 1997; 337: 441–46. Gonzales R, Steiner JF, Lum A, Barrett PH Jr. Decreasing antibiotic use in ambulatory practice: impact of a multidimensional intervention on the treatment of uncomplicated acute bronchitis in adults. JAMA 1999; 281: 1512–19. Damoiseaux RA, de Melker RA, Ausems MJ, van Balen FA. reasons for nonguideline-based antibiotic prescriptions for acute otitis media in The Netherlands. J Fam Pract 1999; 16: 50–53.
Sir—We agree with Otto Cars and colleagues1 about the usefulness of collecting data on antibiotic consumption to help keep antibiotic use to an optimum. Data on hospital use in the UK are rarely collected and made available,2 but data on all primary-care prescriptions are available. In Scotland, the information is released through the prescription reimbursement scheme. They confirm that for 1997, the year chosen by Cars and colleagues, community consumption of antibiotics in Scotland was similar to the overall UK figure at 16·9 defined daily doses per 1000 inhabitants daily. The number of defined daily doses (and number of prescriptions) has fallen consistently since 1995 (1999 vs 1995 change is 213%), such that consumption levels were similar in 1992 and 1999. Scottish data suggest that low prescribing practices have contributed as much to this reduction in prescribing as high prescribing practices (John Reid, personal communication). The reduction probably indicates concern about the worldwide epidemic of antibiotic resistance. Although audits suggest cause for concern about overuse (commonly injudicious) of antibiotics,3,4 serious infections might manifest more frequently with this decline in antibiotic use. We assessed trends in Scotland in the incidence of invasive disease due to methicillin-susceptible Staphylococcus aureus (MSSA), Neisseria meningitidis, Streptococcus pyogenes, and Streptococcus pneumoniae, from bacteraemia reports received between 1991 and 2000 by the Scottish Centre for Infection and Environmental Health. The report rate rose significantly between these years for all four pathogens, but for N meningitidis and especially S pyogenes the incidence has risen recently, which might be related to the decline in antibiotic
THE LANCET • Vol 358 • October 13, 2001
prescribing that began in 1996. From 1991 to 1996 to 2000, reports per 100 000 population of N meningitidis bacteriaemia were 1·2 and 1·2, then increased to 1·6 (1991–96, p=0·1; 1996–2000, p=0·01); reports of S pyogenes bacteraemias increased from 1·4 to 1·5 to 3·1 (p=0·5 and p<0·0001). Some cases might have been hospital acquired, especially for MSSA, but we have no data on community-acquired compared with hospital-aquired rates. Also, S pyogenes bacteraemias certainly need observation for detection of outbreaks; possible renewed virulence of this classic pathogen has been noted.5 If this increase is sustained, better diagnosis of streptococcal infections in primary care will be needed unless we want to see a rebound in antibiotic prescribing. Other factors, such as increasingly susceptible populations, variations in virulence of the organisms, and rising detection rates will, of course, complicate the interpretation of changes in incidence. Moreover, simply relating national trends in prescribing and notification will obscure substantial variations in prescribing at the practice level. A more powerful study design would be to relate cross-sectional and longitudinal variations in prescribing to variations in hospital admission at the national level. The European Union has just funded two European-wide projects to gather data on antibiotic consumption, Antibiotic Resistance Prevention and Control in hospitals and European Surveillance of Antibiotic Consumption in community and hospitals. *I M Gould, R Clarke, S Hutchinson, P Davey *Department of Microbiology, Aberdeen Royal Infirmary, Foresterhill, Aberdeen AB25 2ZN, UK; Information and Statistics Division of the Common Services Agency of the National Health Service; Scottish Centre for Infection and Environmental Health and Department of Public Health, Glasgow University; and Medicines Monitoring Unit, University of Dundee 1
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Cars O, Mölstad S, Melander A. Variation in antibiotic use in the european union. Lancet 2001; 357: 1851–53. Gould IM, Jappy B. Trends in hospital antimicrobial prescribing after 9 years of stewardship. J Antimicrob Chemother 2000; 45: 913–17. Shales DM, Gerding DN, John Jr JF, et al. Society for Healthcare Epidemiology of America and the Infectious Disease Society of America Joint Committee on the prevention of antimicrobial resistance: guidelines for the prevention of antimicrobial resistance in hospitals. Clinical Infect Dis 1997; 25: 584–99. Audit Commission. A prescription for improvement towards more rational prescribing in general practice. London: The Stationery Office, 1994. Anon. Invasive group A streptococcal disease. SCIEH Wkly Rep 2000; 34: 25.
False-positive pneumococcal antigen test in meningitis diagnosis Sir—María Marcos and colleagues (May 12, p 1499)1 report that to diagnose pneumococcal meningitis, the rapid immunochromatographic membrane assay (Binax NOW Streptococcus pneumoniae Urinary Antigen Test, Binax, Portland, ME, USA) used on urine or cerebrospinal fluid (CSF) is at least as sensitive and specific as CSF gram stain and culture. Because of the small number of patients studied, however, they caution about the importance of their results. We report an instance of a false-positive Binax NOW test in a patient with meningitis caused by Streptococcus oralis. A woman aged 67 years was admitted to our hospital because of a cranial trauma. 4 days later she developed fever, headache, and impaired consciousness. Lumbar puncture revealed 24·7⫻109/L polymorphonuclear leucocytes, protein of 5·09 g/L, and glucose of 0·20 mmol/L, with simultaneous plasma glucose of 7·30 mmol/L. A CSF sample was centrifuged at 3000 rpm for 10 min, and a gram stain revealed few gram-positive diplococci. A Binax NOW test done on CSF was positive. Accordingly, we treated the patient with intravenous ceftriaxone 2 g per 4 h and dexamethasone 4 mg per 6 h for 12 days. Culture of the CSF yielded a grampositive, catalase-negative coccus, arranged in pairs that grew aerobically and anaerobically. Surprisingly, conventional tests to identify pneumococcus were negative. Furthermore, a pneumococcusspecific capsular antigen test was also negative. Routine biochemical tests plus biochemical characteristics shown by analytical profile index streptococcus gallery identified the organism as S oralis. A suspension of the strain yielded a positive result on the Binax test, confirming that an antigen was cross-reactive with pneumococcal C polysaccharide. Minimum inhibitory concentration of the strain to penicillin was 0·02 mg/L. The patient did well and microbiological CSF cure was proven after 30 days. S pneumoniae, S oralis, and S mitis are the components of the S oralis group of ␣-haemolytic streptococci. They all share C polysaccharide antigen. Instructions to users given by Binax NOW manufacturer alert that
1273
For personal use. Only reproduce with permission from The Lancet Publishing Group.
2
3
4
5
Stephenson J. Icelandic researchers are showing the way to bring down rates of antibiotic-resistant bacteria. JAMA 1996; 275: 175. Seppala H, Klaukka T, Vuopiio-Varkila J, et al. The effect of changes in the consumption of macrolide antibiotics on erythromycin resistance in group A streptococci in Finland. N Engl J Med 1997; 337: 441–46. Gonzales R, Steiner JF, Lum A, Barrett PH Jr. Decreasing antibiotic use in ambulatory practice: impact of a multidimensional intervention on the treatment of uncomplicated acute bronchitis in adults. JAMA 1999; 281: 1512–19. Damoiseaux RA, de Melker RA, Ausems MJ, van Balen FA. reasons for nonguideline-based antibiotic prescriptions for acute otitis media in The Netherlands. J Fam Pract 1999; 16: 50–53.
Sir—We agree with Otto Cars and colleagues1 about the usefulness of collecting data on antibiotic consumption to help keep antibiotic use to an optimum. Data on hospital use in the UK are rarely collected and made available,2 but data on all primary-care prescriptions are available. In Scotland, the information is released through the prescription reimbursement scheme. They confirm that for 1997, the year chosen by Cars and colleagues, community consumption of antibiotics in Scotland was similar to the overall UK figure at 16·9 defined daily doses per 1000 inhabitants daily. The number of defined daily doses (and number of prescriptions) has fallen consistently since 1995 (1999 vs 1995 change is 213%), such that consumption levels were similar in 1992 and 1999. Scottish data suggest that low prescribing practices have contributed as much to this reduction in prescribing as high prescribing practices (John Reid, personal communication). The reduction probably indicates concern about the worldwide epidemic of antibiotic resistance. Although audits suggest cause for concern about overuse (commonly injudicious) of antibiotics,3,4 serious infections might manifest more frequently with this decline in antibiotic use. We assessed trends in Scotland in the incidence of invasive disease due to methicillin-susceptible Staphylococcus aureus (MSSA), Neisseria meningitidis, Streptococcus pyogenes, and Streptococcus pneumoniae, from bacteraemia reports received between 1991 and 2000 by the Scottish Centre for Infection and Environmental Health. The report rate rose significantly between these years for all four pathogens, but for N meningitidis and especially S pyogenes the incidence has risen recently, which might be related to the decline in antibiotic
THE LANCET • Vol 358 • October 13, 2001
prescribing that began in 1996. From 1991 to 1996 to 2000, reports per 100 000 population of N meningitidis bacteriaemia were 1·2 and 1·2, then increased to 1·6 (1991–96, p=0·1; 1996–2000, p=0·01); reports of S pyogenes bacteraemias increased from 1·4 to 1·5 to 3·1 (p=0·5 and p<0·0001). Some cases might have been hospital acquired, especially for MSSA, but we have no data on community-acquired compared with hospital-aquired rates. Also, S pyogenes bacteraemias certainly need observation for detection of outbreaks; possible renewed virulence of this classic pathogen has been noted.5 If this increase is sustained, better diagnosis of streptococcal infections in primary care will be needed unless we want to see a rebound in antibiotic prescribing. Other factors, such as increasingly susceptible populations, variations in virulence of the organisms, and rising detection rates will, of course, complicate the interpretation of changes in incidence. Moreover, simply relating national trends in prescribing and notification will obscure substantial variations in prescribing at the practice level. A more powerful study design would be to relate cross-sectional and longitudinal variations in prescribing to variations in hospital admission at the national level. The European Union has just funded two European-wide projects to gather data on antibiotic consumption, Antibiotic Resistance Prevention and Control in hospitals and European Surveillance of Antibiotic Consumption in community and hospitals. *I M Gould, R Clarke, S Hutchinson, P Davey *Department of Microbiology, Aberdeen Royal Infirmary, Foresterhill, Aberdeen AB25 2ZN, UK; Information and Statistics Division of the Common Services Agency of the National Health Service; Scottish Centre for Infection and Environmental Health and Department of Public Health, Glasgow University; and Medicines Monitoring Unit, University of Dundee 1
2
3
4
5
Cars O, Mölstad S, Melander A. Variation in antibiotic use in the european union. Lancet 2001; 357: 1851–53. Gould IM, Jappy B. Trends in hospital antimicrobial prescribing after 9 years of stewardship. J Antimicrob Chemother 2000; 45: 913–17. Shales DM, Gerding DN, John Jr JF, et al. Society for Healthcare Epidemiology of America and the Infectious Disease Society of America Joint Committee on the prevention of antimicrobial resistance: guidelines for the prevention of antimicrobial resistance in hospitals. Clinical Infect Dis 1997; 25: 584–99. Audit Commission. A prescription for improvement towards more rational prescribing in general practice. London: The Stationery Office, 1994. Anon. Invasive group A streptococcal disease. SCIEH Wkly Rep 2000; 34: 25.
False-positive pneumococcal antigen test in meningitis diagnosis Sir—María Marcos and colleagues (May 12, p 1499)1 report that to diagnose pneumococcal meningitis, the rapid immunochromatographic membrane assay (Binax NOW Streptococcus pneumoniae Urinary Antigen Test, Binax, Portland, ME, USA) used on urine or cerebrospinal fluid (CSF) is at least as sensitive and specific as CSF gram stain and culture. Because of the small number of patients studied, however, they caution about the importance of their results. We report an instance of a false-positive Binax NOW test in a patient with meningitis caused by Streptococcus oralis. A woman aged 67 years was admitted to our hospital because of a cranial trauma. 4 days later she developed fever, headache, and impaired consciousness. Lumbar puncture revealed 24·7⫻109/L polymorphonuclear leucocytes, protein of 5·09 g/L, and glucose of 0·20 mmol/L, with simultaneous plasma glucose of 7·30 mmol/L. A CSF sample was centrifuged at 3000 rpm for 10 min, and a gram stain revealed few gram-positive diplococci. A Binax NOW test done on CSF was positive. Accordingly, we treated the patient with intravenous ceftriaxone 2 g per 4 h and dexamethasone 4 mg per 6 h for 12 days. Culture of the CSF yielded a grampositive, catalase-negative coccus, arranged in pairs that grew aerobically and anaerobically. Surprisingly, conventional tests to identify pneumococcus were negative. Furthermore, a pneumococcusspecific capsular antigen test was also negative. Routine biochemical tests plus biochemical characteristics shown by analytical profile index streptococcus gallery identified the organism as S oralis. A suspension of the strain yielded a positive result on the Binax test, confirming that an antigen was cross-reactive with pneumococcal C polysaccharide. Minimum inhibitory concentration of the strain to penicillin was 0·02 mg/L. The patient did well and microbiological CSF cure was proven after 30 days. S pneumoniae, S oralis, and S mitis are the components of the S oralis group of ␣-haemolytic streptococci. They all share C polysaccharide antigen. Instructions to users given by Binax NOW manufacturer alert that
1273
For personal use. Only reproduce with permission from The Lancet Publishing Group.