What is the difference between narrow and broad spectrum antibiotics

Through 30 days, children 8. Broad-spectrum antibiotics were not superior to narrow-spectrum antibiotics for any clinical outcomes in the stratified analysis or in the full matched analysis. Receiving broad-spectrum antibiotics was associated with a higher risk of adverse events requiring clinical care compared with receiving narrow-spectrum antibiotics risk at 14 days, 3.

Similarly, for adverse events at 14 days, the association of an unobserved confounder with both outcome and treatment group would require a relative risk of 4. Results for outcomes on day 14 stratified by diagnosis appear in eTable 5 in the Supplement.

Broad-spectrum antibiotics were not superior to narrow-spectrum antibiotics for acute otitis media or acute sinusitis, but were associated with reduced risk of treatment failure for group A streptococcal pharyngitis risk of 1. Enrolled children had similar characteristics to sampled children who were not enrolled eTable 6 in the Supplement. White children and those with public insurance were less likely to have both interviews completed eTable 7 in the Supplement.

The first interview revealed that 77 children 3. For 33 children, the new antibiotic was a different spectrum than the original. For 22 children, the parent did not report the name of the new antibiotic. Therefore, 55 children 2. The stratified analysis included clinicians median, 7 children per clinician; range, children per clinician resulting in diagnosis strata children diagnosed as having acute otitis media, as having group A streptococcal pharyngitis, and as having acute sinusitis.

Broad-spectrum antibiotics were associated with a slightly worse quality-of-life score and more adverse events compared with narrow-spectrum antibiotics, but no association was found with other patient-centered outcomes Table 4.

The odds ratios appear in eTable 13 and an explanation of the sample sizes appears in the eText in the Supplement. The results were consistent across the stratified analysis and the full matched analysis. The overall mean PedsQL score was In the post hoc analyses, results from the hierarchical analysis were consistent and the results from the analysis restricted to children with parent-reported symptoms at baseline also were consistent but not statistically significant eText in the Supplement.

In a sensitivity analysis, a potential unobserved confounder would have required a relative risk of 2. Receiving broad-spectrum antibiotics was associated with a higher risk of adverse events compared with receiving narrow-spectrum antibiotics risk of The results of the analyses that accounted for missing data were similar eText in the Supplement.

Among the children Results stratified by acute respiratory tract infection diagnosis were consistent across diagnoses eTable 14 in the Supplement ; however, there was a limited difference in adverse events by antibiotic spectrum for children diagnosed with acute sinusitis. This study used a diverse, pediatric primary care network to compare the 2 prevailing treatment strategies for the most common childhood infections.

Broad-spectrum antibiotics did not perform better than narrow-spectrum antibiotics on clinical or patient-centered outcomes, but were associated with a higher rate of adverse events than narrow-spectrum antibiotics.

These data support the use of narrow-spectrum antibiotics for the treatment of acute respiratory tract infections in most children. Assessing outcomes identified as important by legal guardians of children with acute respiratory tract infections distinguished this work. The consistency of findings across clinical and patient-derived outcomes was notable. This remained true in the subanalyses by individual acute respiratory tract infection, with the lone exception of group A streptococcal pharyngitis in the retrospective electronic health record-based cohort, in which a lower rate of treatment failure was observed with broad-spectrum antibiotic therapy.

Although adverse events rates were higher for broad-spectrum antibiotics in both cohorts, the overall rates of adverse events identified in the prospective cohort were This study had several limitations.

Because children were identified based on clinician diagnosis plus an antibiotic prescription to identify bacterial acute respiratory tract infections, some children likely had viral infections. This misclassification could have blunted the ability to detect a difference between antibiotic choices. This approach, however, reflects the true incidence of antibiotic prescribing for acute respiratory tract infections and, therefore, captures its association with symptom resolution, adverse events, and quality of life.

Residual confounding likely persists, but sensitivity analyses suggest that this is unlikely to explain the study findings. Although conducted in a large and diverse primary care network, results might not be generalizable outside this setting.

Because children who had received antibiotics within the previous 30 days were excluded from the study, the potential benefits of broad-spectrum antibiotics for these children could not be assessed. All pooled comparisons were prespecified, but because of the multiplicity of end points, comparisons of these results using conventional levels of statistical significance should only be made cautiously.

Specific to the prospective cohort study, the PedsQL was used to capture the outcome of child quality of life. This outcome was identified as a key concern by legal guardians and children in the qualitative study.

Although the PedsQL is a validated instrument that captures social, physical, emotional, and school functioning and it has been demonstrated to be feasible and have good construct and discriminant validity and responsiveness in measuring short-term outcomes after minor acute episodes of illness or injury, 25 , 40 it has not been specifically validated for acute respiratory tract infections.

In addition, prior work estimated that a difference of more than 4 points on the PedsQL was a clinically meaningful difference. Instead, this finding rejects the notion that broad-spectrum antibiotics provide a clinically meaningful advantage. Although the relatively high overall PedsQL scores suggest a potential ceiling effect of this measure, the distribution shift was in favor of narrow-spectrum antibiotics, which was consistent across most outcomes and analyses, and the sensitivity analysis indicated that there would need to be very strong residual confounding to shift the PedsQL results in favor of broad-spectrum antibiotics.

In addition, because the PedsQL was assessed at only a single time point, we could not assess the effect of antibiotic spectrum on the change in score from baseline. However, when the full sample of eligible participants was compared with the children included in the cohort, differences in patient characteristics were negligible. Fifteen percent of families who completed the first interview between day 5 and 10 did not complete the second interview between day 14 and The assessment of only 1 outcome adverse events and 2 covariates race and ethnicity at the second interview, however, minimized the effect of these missing data and a sensitivity analysis accounting for the missing adverse event outcome yielded similar results as the primary analysis.

The specific questions used to elicit the outcomes from legal guardians by telephone interview were not validated or tested for reliability. They were, however, tested for feasibility and family partners confirmed the face validity and clarity of these questions.

Some imbalance of race, insurance, and practice type remained after matching for group A streptococcal pharyngitis. This imbalance was addressed by including practice type, which is the likely driver of imbalance in race and insurance, in the response models. Remaining imbalance in season was both restricted to a single season and inconsistent and, thus, likely to be an artifact. Although this could have resulted in uncontrolled confounding, results were robust to multiple analyses.

Among children with acute respiratory tract infections, broad-spectrum antibiotics were not associated with better clinical or patient-centered outcomes compared with narrow-spectrum antibiotics, and were associated with higher rates of adverse events.

Corresponding Author: Jeffrey S. Author Contributions: Dr Gerber had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis. Dr Zaoutis reported serving as a consultant to T2 Biosystems and Nabriva. Dr Fiks reported receiving a Pfizer independent research grant.

No other disclosures were reported. Disclaimer: The statements presented in this publication are solely the responsibility of the authors and do not necessarily represent the views of PCORI or its board of governors or methodology committee. Mr Massey received administrative support for this project, which included compensation from PCORI for help with recruiting practices for the intervention.

We also thank the family advisory council not compensated for their support and guidance on this project from conception through execution; Susan L. Our website uses cookies to enhance your experience. By continuing to use our site, or clicking "Continue," you are agreeing to our Cookie Policy Continue.

Figure 1. View Large Download. Figure 2. Table 1. Table 2. Table 3. Table 4. Patient-Centered Outcomes in the Prospective Cohort. Diagnosis codes for acute respiratory tract infections eTable 2.

Appropriate antibiotics with classification for treatment of acute respiratory tract infections eTable 3. Odds ratios for clinical outcomes eTable 5. Clinical outcomes, results stratified by diagnosis eTable 6.

Prospective patient-centered outcome cohort: Comparison of patient characteristics of children who did and did not complete the day interview eTable 8.

Odds ratios for patient-centered outcomes eTable Patient-centered outcomes, results stratified by diagnosis eText eFigure. Trends of outpatient prescription drug utilization in US children, PubMed Google Scholar Crossref. Antibiotic prescribing in ambulatory pediatrics in the United States. Antibiotic prescription rates for acute respiratory tract infections in US ambulatory settings. Antimicrobial drug prescription in ambulatory care settings, United States, Emerg Infect Dis.

Predictors of broad-spectrum antibiotic prescribing for acute respiratory tract infections in adult primary care.

Frequency of first-line antibiotic selection among US ambulatory care visits for otitis media, sinusitis, and pharyngitis. US emergency department visits for outpatient adverse drug events, A placebo-controlled trial of antimicrobial treatment for acute otitis media. N Engl J Med. Treatment of acute otitis media in children under 2 years of age. IDSA clinical practice guideline for acute bacterial rhinosinusitis in children and adults.

If the pathogen and its in vitro susceptibility pattern are known, narrow-spectrum antibiotics are preferable. The carefully standardized conditions of in vitro testing do not correlate with the in vivo situation, in which the effectiveness of antibiotics is altered by diffusion and immune response.

The in vitro tests available do not always correlate with the clinical situation; some bacteria showing resistance in the laboratory are actually susceptible in practice in some infection sites, and vice versa. Fungus Plural: fungi A multicellular organism with cell walls and nuclei, but lacking chlorophyll. The fungi include many unrelated or only distantly related organisms, such as mushrooms, yeast such as that used in making bread or beer , and the molds for example, those that are used in making cheese or that cause rotting of food.

Fungi can cause many plant and animal diseases. However, they are also the source of a number of useful antibiotics for example, penicillin, which comes from the Penicillium mold. Gene Segment of a DNA molecule carrying instructions for the construction of a protein; a unit of heredity. Generic vs. The generic name is the common family identification provided by chemists, for example "Amoxicillin.

One trade name for Amoxicillin is Augmentin. Gram-positive vs. Cell walls of gram-negative bacteria are more permeable - they do not retain much of the dye, and so their cell walls do not show much stain. Growth promoters A class of substances, usually antibiotics, used at low doses to promote growth in food animals.

Horizontal gene transfer Exchange of genetic material between two microorganisms; no new microorganism is created.

Host A multicellular organism such as a tree, dog, or human colonized by either commensal or pathogenic microorganisms. Microorganism Living organisms that are microscopic or submicroscopic: they cannot be seen with the human eye.

They include bacteria, some fungi, and protozoa. Viruses are sometimes included in this category, although some scientists do not include viruses as microorganisms because they do not think that viruses should be classified as living organisms. Multiple drug resistance The ability of an organism to resist several different drugs. Narrow-spectrum vs.

Narrow-spectrum antibiotics are active against a select group of bacterial types. Broad-spectrum antibiotics are active against a wider number of bacterial types and, thus, may be used to treat a variety of infectious diseases.

Broad-spectrum antibiotics are particularly useful when the infecting agent bacteria is unknown. Examples of narrow-spectrum antibiotics are the older penicillins penG , the macrolides and vancomycin.

Examples of broad-spectrum antibiotics are the aminoglycosides, the 2nd and 3rd generation cephalosporins, the quinolones and some synthetic penicillins.

Natural selection A process by which organisms that are better adapted to their environment thrive and multiply, while organisms that are less well adapted to their environment fail to thrive and do not reproduce successfully.

Non-public health antimicrobial agents Agents that control or inhibit odor-causing bacteria. See public health antimicrobial agents. Nosocomial infections Infections that are acquired in a hospital while undergoing treatment for a different condition. Pathogen A microorganism, virus, or other substance that causes disease in another organism, the host.