Differences In Antibiotic Use Research Articles

The Relationship Between Acute Mastoiditis and Antibiotic Use for Acute Otitis Media in Children

To determine the relationship between prior antibiotic use and the development of acute mastoiditis (AM) in children. Retrospective review. Tertiary pediatric center. We identified 129 patients with AM who were admitted to our center between 1996 and 2005. Proportion of children who developed AM. A total of only 67 patients (51.9%) had undergone any antimicrobial treatment prior to hospital admission. In 1996, 64% of patients with AM had received antibiotics for acute otitis media (AOM) prior to admission (n = 7 of 11), but this percentage had steadily decreased to 27% by 2005 (n = 4 of 15). The yearly number of cases of AM treated in our institution has remained stable over this period. A subperiosteal abscess was identified in 45 patients (34.9%), while the remainder (n = 84) had postauricular inflammation only (65.1%). Nineteen patients with a subperiosteal abscess (42%) and 48 patients without a subperiosteal abscess (57%) had undergone prehospitalization antimicrobial therapy for suppurative AOM. There was no significant difference in antibiotic use between the numbers of patients with or without a subperiosteal abscess. Regarding the sensitivity of bacteria isolated from patients with a subperiosteal abscess, only 1 patient was infected with an organism that was not sensitive to the prehospitalization antibiotic prescribed. Use of antibiotics to treat suppurative AOM in children might not influence the subsequent development of AM.

Relationship between Antibiotic Exposure and Subsequent Clostridium Difficile-Associated Diarrhea

Objective The objective of this study was to assess the relationship between antibiotic exposure and subsequent Clostridium difficile-associated diarrhea (CDAD) in hospitalized patients. Methods A retrospective, case-control study with data collected between October 1, 2005 and March 31, 2006 was conducted. Cases consisted of patients with a documented new onset of diarrhea occurring a minimum of 72 hours following admission to the hospital and accompanied by a positive C. difficile toxin A and B enzyme immunoassay. Two controls were matched to each case according to known risk factors for CDAD other than antibiotic use. A complete assessment of antibiotic use was made, including all regimens the patient received during the previous 8 weeks. The difference in antibiotic use in cases and controls was tested using the chi-square test. The association between specific antibiotic classes and subsequent CDAD was evaluated with an odds ratio. Results Prior antibiotic exposure was observed more frequently in these cases than in controls ( P = 0.035). Specifically, third-generation cephalosporins were found to be significantly associated with CDAD (odds ratio, 4.64; 95% confidence interval, 1.64 to 13.14). Conclusion This study showed that prior antibiotic exposure is associated with increased incidence of subsequent CDAD. Specifically, third-generation cephalosporins were statistically associated with CDAD. Although results did not reach statistical significance, this study suggests that potential associations may exist between CDAD and prior exposure to antipseudomonal penicillins, cefepime, carbapenems, fluoroquinolones, and intravenous vancomycin.

Helicobacter pylori and Clostridium difficile in Cystic Fibrosis Patients

We describe the prevalence of H. pylori and toxigenic Clostridium difficile (CD) infection and its relationship with gastrointestinal symptoms and pancreatic sufficiency (PS) or insufficiency (PI) in cystic fibrosis (CF) patients. Stool specimens from 30 consecutive patients with CF, aged 1-44, and from 30 healthy similarly aged subjects were tested for the H. pylori antigen by specific monoclonal antibodies and for CD toxins by Tox A/B assay and Tox A assay. CF patients were assessed clinically and tested for specific H. pylori serum antibodies and for mutations. In CF patients, the prevalence of H. pylori antigen was 16.6% (5/30), compared to 30% (9/30) in controls. Of the 26 CF patients with PI, only 2 (7.6%) were infected by H. pylori, compared with 3 of the 4 (75%) patients with PS (P=0.001). H. pylori infection was diagnosed in 3 of 5 (60%) CF patients carrying mild mutations, compared to 1 of 25 (4%) CF patients carrying severe mutations (P=0.01). Fourteen of 30 (46.6%) stool specimens from CF patients tested positive in the ToxA/B assay, and 3 of 14 tested positive for ToxA. No significant differences in antibiotic use, severity of lung disease, PI, chronic abdominal pain, or genotype were found between the two groups. None of the controls was positive for CD toxins. Prevalence of H. pylori infection in CF patients was lower than in similarly aged non-CF controls. CF patients with PI or a history of distal intestinal obstruction syndrome and those carrying mutations associated with a severe phenotype were protected against H. pylori infection. Almost half of the CF patients were asymptomatic carriers of CD producing mostly toxin B. More studies are needed to confirm our results in a larger group of CF patients.

Comparison of antibiotic use between an 'open' and a 'closed' intensive care unit

To determine differences in antibiotic use between a 'closed' ICU in a hospital in Israel and an 'open' ICU in a Kenyan hospital. Retrospective comparative study. The ICU of Beilinson hospital in Rabin Medical Centre, Tel Aviv, Israel and the ICU of Mater Hospital, Nairobi Kenya. One hundred and forty patients from Beilinson and one hundred fifty one patients from Mater Hospital were enroled. Antibiotic use in the different ICU settings. Seven different antibiotics namely Erythromycin, Meropenem, Taxobactam/Piperacillin, Metronidazole, Gentamycin, Ceftriaxone and Cefuroxime were used in sufficient numbers in both centres to allow for statistical analysis. Four of these seven namely metronidazole, gentamycin, ceftriaxone and cefuroxime demonstrated statistically significant difference between the two centres. The level, of antibiotic use is demonstrably higher in 'open' ICUs with fewer controls to antibiotic prescriptions than in 'closed' ICUs with stricter control.

Antibiotic use and resistance in public-sector hospitals in KwaZulu-Natal

To investigate a possible association between level of care, antibiotic use and antimicrobial resistance in 16 public-sector hospitals providing different levels of care in KwaZulu-Natal. A multicentre surveillance study was undertaken in 16 hospitals at three progressive levels of health care (district, regional, tertiary) where each hospital submitted 100 consecutive, non-repetitive isolates judged in the laboratory to be of potential clinical significance. Isolates were identified and susceptibility testing was undertaken using the Kirby-Bauer disc diffusion method with minimum inhibitory concentrations (MICs) extrapolated on an automated reading system. Isolates were grouped according to their natural resistance profiles, and percentage susceptibility, mean percentage susceptibility and standard deviation to each antibiotic were stratified within and across hospital levels. Antibiotic use data were expressed as the number of daily divided doses (DDDs) per 1000 patient-days. Two tertiary, 9 regional and 5 district public hospitals in KwaZulu-Natal. Percentage susceptibility. There was a general trend among the 1 270 isolates of highest susceptibility in district hospitals, followed by regional and then tertiary hospitals. This is consistent with the referral system where health conditions become increasingly severe/complex requiring greater antibiotic use and broader-spectrum agents at progressive hospital levels, with statistical significance (p < 0.05) evident where sample numbers were relatively large. Trend variations could be associated with the qualitative and quantitative differences in antibiotic use, albeit without statistical corroboration. Three per cent of the total number of isolates were sensitive to all antibiotics tested and 6% were resistant to a single agent only. The remaining 91% showed acquired resistance to more than one drug. The standard deviation ranged from 0% to 55%. This study showed that resistance profiles among bacteria varied greatly within and across hospital levels. While antibiotic use varied as much, a statistically significant correlation between use and resistance could not be established. It was therefore postulated that the effect of selection pressure was obscured by other resistance determinants apparent in public hospitals in resource-poor settings. On a clinical level, the study showed that resistance profiles among bacteria vary too much to allow a national antibiotic policy as proposed in the standard treatment guidelines. Rather, such guidelines should be directed to specific profiles found in different hospitals and at different levels of health care. Regular surveillance to adjust such guidelines is essential.

Specific risk factors for Clostridium difficile-associated diarrhea: A prospective, multicenter, case control evaluation

Clostridium difficile is a toxin-producing bacterium that is responsible for toxicity to the colonic mucosa, causing inflammation, necrosis, and, in some extreme cases, intestinal dilation and perforation. C difficile-associated diarrhea (CDAD) occurs when patients have a reduction in their natural gastrointestinal flora that allows for the proliferation of and toxin production by C difficile. Using a multicenter, prospective observational case control study, we assessed and quantified risk factors associated with the development of diarrhea caused by Clostridium difficile, with particular attention to antibiotic use. All hospitalized patients with diarrhea requiring a C difficile toxin test as part of their routine clinical workup were considered for study inclusion. Patients with a negative specimen (controls) were considered for enrollment if matched (by age, sex, length of stay, and institution) to a case. Variables associated with CDAD were identified using univariate analysis. Significant factors were then entered into multivariate logistic regression analysis to identify independent factors. There were no significant differences in antibiotic use between cases and controls. Patient severity, classified by Horn's Index, was significantly different between cases and controls (P = .0022). No other significant variables were identified. The severity of illness of the cases was classified as more severe than the controls, but no significant differences in antibiotic use were identified between the groups. The negative C difficile toxin studies on the well-matched control patients indicate a different etiology of diarrhea (such as antibiotic-associated diarrhea), which may have developed in the presence of similar antibiotic use as the cases.

Decrease in antibiotic use among children in the 1990s: not all antibiotics, not all children.

Decreases in antibiotic use were widely reported in the 1990s. This study was undertaken to determine trends in the use of antibiotics from fiscal year (FY) 1995 (April 1995 to March 1996) to FY 2001 in a complete population of Manitoba children. Using Manitoba's health care databases, we determined annual population-based rates of antibiotic prescription among children by antibiotic class (narrow-spectrum and broader-spectrum antibiotics), age group, physician diagnosis (e.g., otitis media or bronchitis) and neighbourhood income in urban areas (derived from the 1996 census). Antibiotic prescription rates were generated within a generalized linear model framework with general estimating equations, and differences between FY 2001 and FY 1995 were tested. Differences in antibiotic use over time were compared across antibiotic classes, age groups, diagnoses and income neighbourhoods. The overall antibiotic prescription rate decreased by almost one-third, from 1.2 prescriptions per child in FY 1995 to 0.9 prescriptions in FY 2001. Total antibiotic use declined for all respiratory tract infections; decreases were greatest for the sulfonamides (decrease to less than one-third the FY 1995 rate) and narrow-spectrum macrolides (decrease to less than half the FY 1995 rate). In contrast, the FY 2001 rate for broader-spectrum macrolides was as much as 12.5 times the FY 1995 rate. Otitis media accounted for one-quarter of the use of the latter agents. Preschool children and low-income children received the greatest number of antibiotic prescriptions. Declines in antibiotic prescriptions were of a lesser magnitude for low-income children (for whom rates in FY 2001 were four-fifths the rates in FY 1995) than for higher-income children (for whom rates in FY 2001 were about two-thirds the rates in FY 1995). Overall, antibiotic use declined over the late 1990s in this population of Canadian children, but the increasing use of broader-spectrum macrolides and higher rates of antibiotic use among preschool and low-income children may have implications for antibiotic resistance.

Effect of social and climatological factors on antimicrobial use and Streptococcus pneumoniae resistance in different provinces in Spain.

To investigate the association between geographical differences in antibiotic consumption and resistance of Streptococcus pneumoniae to penicillin and erythromycin in 15 provinces of Spain, taking into account the potential influence of a series of social and climatological factors. Possible correlations between prevalence of resistance to penicillin and erythromycin of S. pneumoniae, as determined in the national reference laboratory, and antibiotic consumption, and socio-economic and climatological variables were investigated. Partial correlations and multivariate linear regression were performed to assess the relative importance of variables predicting resistance and to investigate explicative factors for antibiotic consumption, respectively. A correlation was found between resistance and educational level, the proportion of young people in the population and climate, but was explained by their effects on differences in antibiotic use, which appeared to be the basic and only force behind resistance patterns in different geographical areas. Antibiotic use was found to be determined by the interplay of adult illiteracy, rainfall and GDP per capita. Interventions aimed at improving educational level and economic growth might therefore be followed by a noticeable reduction in overall antibiotic consumption, which might in turn be followed by a reduction in penicillin and erythromycin resistance in clinical isolates of S. pneumoniae.

Development of the choices and acquisition of antibiotics model from a descriptive study of a Lay Honduran population

Antibiotic resistance is a global public health problem that is accelerated by overuse and misuse of antibiotics. In today's world of increasing international travel and exchange of goods, the spread of antibiotic resistant organisms is a growing threat. Despite significant antibiotic use in developing nations, research to describe and curtail inappropriate use is limited. In this study, the investigators developed a model of antibiotic use, choices and acquisition of antibiotics model, from a study of a lay population in Honduras. A representative sample of 939 rural and urban Hondurans completed the Preguntas Para El Uso de Antibiotics questionnaire to determine how the participant made choices about antibiotic use. The study indicated that the rural participants used significantly fewer antibiotics than the urban participants and that the demographic indicators did not show a significant difference in antibiotic use in those of lower socioeconomic status. In addition, the participants reported that they seek out professional advice and care rather than self-prescribing. Implications for educational and empowerment programs based on the model are discussed.

Análisis del consumo de antibióticos en la Comunidad Valenciana durante los años 2000-2002

To quantify antibiotic prescriptions in the Autonomous Community of Valencia in the years 2000-2002 and analyze the differences in antibiotic use among 20 Valencian Community health areas. Retrospective observational population study (3,983,464 inhabitants) of prescriptions recorded in Valencian Community pharmacies during the period 2000-2002. We calculated defined daily doses per 1000 inhabitants and day (DHD), for the population without pharmaceutical fees (e.g. pensioners), the population with pharmaceutical fees (e.g. actively working) and the total population. The antibiotics analyzed belonged the J01 group (ATC/DDD classification). Antibiotic consumption was 26.47 DHD in 2000, 23.56 DHD in 2001 and 23.48 DHD in 2002. The most frequently prescribed drug groups included: broad-spectrum penicillins (J01C) 11.8 DHD, macrolides (J01F) 5.6 DHD, and other beta-lactams (J01D) 3.95 DHD. There was considerable variation between the population without pharmaceutical fees and the population with pharmaceutical fees: JO1C (DHD 18.49 vs. 9.73), JO1F (11.06 vs. 3.84) and quinolones (J01M) (9.16 vs. 1.22) (p < 0.05). There was also substantial variation between areas, both overall and by groups (p < 0.05): J01C 6.36 DHD to 12.14 DHD; (J01F), 3.78 DHD to 6.08 DHD; (J01D), 2.28 DHD to 4.65 DHD, and (J01M) 2.39 DHD to 3.6 DHD. There was a slight trend to decreasing antibiotic use in the Community of Valencia over the period of 2000-2002. The population without pharmaceutical fees showed much higher antibiotic use than those with pharmaceutical fees, and there was considerable variation in prescriptions between the different public health care areas.

Are Pediatricians Adhering to Principles of Judicious Antibiotic Use for Upper Respiratory Tract Infections?

In 1997, the Centers for Disease Control and Prevention (CDC), in collaboration with other professional organizations, released principles for judicious use of antibiotics in pediatric upper respiratory illnesses (URI). This study compared use of antibiotics for URI in children before (1995) and after (1998) publication of the principles and compared survey responses with practice habits. A questionnaire was mailed to a sample of pediatricians in northern Virginia. Office records of a randomly selected subset of pediatricians were reviewed. Seventy-five percent of pediatricians completed the questionnaire; 51/149 (34%) chose to prescribe antibiotics for purulent rhinorrhea of less than 10 days' duration. This was significantly lower than that reported in the 1995 survey. However, review of office records of a random sample of these pediatricians revealed no significant difference in antibiotic use in children with uncomplicated URI in the 2 years studied. Injudicious antibiotic use for URI is prevalent among pediatricians in northern Virginia. Actual practice habits are at variance with response to case vignettes.

The epidemiology of vancomycin-resistant enterococci

Major differences in the epidemiology of vanA carrying enterococci exist between Europe and the USA, where these organisms have been well investigated. These differences are probably related to the differences in antibiotic use in humans and animals in both continents, but more research is needed before firm conclusions can be drawn.

Colonization with coagulase-negative staphylococci in two neonatal units

Episodes of septicaemia due to coagulase-negative staphylococci (CNS) were more frequent in a level III than in a level II neonatal unit in Stockholm, Sweden. Colonization with CNS during the first 2 weeks of life was investigated in 10 infants from each unit. As the use of antibiotics differed between the two units, the aim was to correlate colonization and antimicrobial resistance patterns to antibiotic usage. Antimicrobial susceptibility of CNS to isoxazolylpenicillins, co-trimoxazole, erythromycin, clindamycin, chloramphenicol and gentamicin was determined. Selected isolates were typed with restriction endonuclease analysis of plasmid DNA and of genomic DNA. Infants were frequently colonized with multiple strains and species of CNS, and transmission of strains from patient to patient occurred within the unit. Qualitative and quantitative differences in antibiotic use were not correlated with colonization. The prevalence of resistant isolates, mostly of Staphylococcus haemolyticus, was higher in the level II unit with lower use of antibiotics. Staphylococcus epidermidis, which is generally more virulent, prevailed in the level III unit, where there were more severely ill children and invasive procedures were more frequently performed.

Production of betalactamase by respiratory tract bacteria in children: relationship to antibiotic use.

Sales of antibiotics have increased in Sweden during the past decade. This has been paralleled by an increase in the frequency of beta-lactamase-producing respiratory tract bacteria. To investigate the effects of regional differences in use of antibiotics on beta-lactamase production in respiratory tract bacteria, we collected nasopharyngeal specimens and information about antibiotic use from 1133 children attending day-care centres in four rural municipalities with low use, and one urban municipality with high use of antibiotics, use being assessed from pharmacy sales. The frequency of beta-lactamase production among isolates of Branhamella catarrhalis and Moraxella nonliquefaciens was significantly higher in the urban municipality. This appeared to be a long-term ecological effect of differences in the level of use of antibiotics between the urban and rural populations, rather than an effect of recent antibiotic treatment of individual patients.

Blockage of urinary catheters: Role of microorganisms and constituents of the urine on formation of encrustations

Long-term indwelling urinary catheters may become blocked in some patients by formation of encrustations made up of aggregated struvite crystals while other patients rarely develop blocked catheters. We have designated these groups as “blockers”, “intermediates” or “non-blockers”. To further understand this phenomenon we followed 32 catheterized elderly women in a nursing home. Catheters were changed six times at 2 week intervals. Patients tended to remain as “blockers”, “intermediates” or “non-blockers” consistently over time. There were no significant differences in use of antibiotics, clinical manifestations of urinary infection or fever among the groups. “Blockers” were significantly more often colonized with Proteus mirabilis and Providencia stuartii than “non-blockers”, and significantly less often with Klebsiella pneumoniae. However, there was no evidence of interference among the organisms. “Blockers” excreted a significantly more alkaline urine, and lesser amounts of magnesium, urea and phosphate in their urine. Two “blockers” in whom Proteus sp. were eliminated by coincidental antimicrobial therapy converted to “non-blockers”. These findings support the concept that “blockers” are patients who have prolonged colonization with urease producing Proteus mirabilis and Providencia stuartii.