Health professionals' views about who would benefit from using a closed-loop system: a qualitative study.

AIM: To explore health professionals' views about who would benefit from using a closed-loop system and who should be prioritized for access to the technology in routine clinical care. METHODS: Health professionals (n = 22) delivering the Closed Loop from Onset in type 1 Diabetes (CLOuD) trial were interviewed after they had ≥ 6 months' experience supporting participants using a closed-loop system. Data were analysed thematically. RESULTS: Interviewees described holding strong assumptions about the types of people who would use the technology effectively prior to the trial. Interviewees described changing their views as a result of observing individuals engaging with the closed-loop system in ways they had not anticipated. This included educated, technologically competent individuals who over-interacted with the system in ways which could compromise glycaemic control. Other individuals, who health professionals assumed would struggle to understand and use the technology, were reported to have benefitted from it because they stood back and allowed the system to operate without interference. Interviewees concluded that individual, family and psychological attributes cannot be used as pre-selection criteria and, ideally, all individuals should be given the chance to try the technology. However, it was recognized that clinical guidelines will be needed to inform difficult decisions about treatment allocation (and withdrawal), with young children and infants being considered priority groups. CONCLUSIONS: To ensure fair and equitable access to closed-loop systems, prejudicial assumptions held by health professionals may need to be addressed. To support their decision-making, clinical guidelines need to be made available in a timely manner.

Use of self-collected capillary blood samples for islet autoantibody screening in relatives: a feasibility and acceptability study.

AIMS: To evaluate the feasibility of using self-collected capillary blood samples for islet autoantibody testing to identify risk in relatives of people with Type 1 diabetes. METHODS: Participants were recruited via the observational TrialNet Pathway to Prevention study, which screens and monitors relatives of people with Type 1 diabetes for islet autoantibodies. Relatives were sent kits for capillary blood collection, with written instructions, an online instructional video link and a questionnaire. Sera from capillary blood samples were tested for autoantibodies to glutamic acid decarboxylase, islet antigen-2, insulin and zinc transporter 8. 'Successful' sample collection was defined as obtaining sufficient volume and quality to provide definitive autoantibody results, including confirmation of positive results by repeat assay. RESULTS: In 240 relatives who returned samples, the median (range) age was 15.5 (1-49) years and 51% were male. Of these samples, 98% were sufficient for glutamic acid decarboxylase, islet antigen-2 and zinc transporter 8 autoantibody testing and 84% for insulin autoantibody testing and complete autoantibody screen. The upper 90% confidence bound for unsuccessful collection was 4.4% for glutamic acid decarboxylase, islet antigen-2 and/or zinc transporter 8 autoantibody assays, and 19.3% for insulin autoantibodies. Despite 43% of 220 questionnaire respondents finding capillary blood collection uncomfortable or painful, 82% preferred home self-collection of capillary blood samples compared with outpatient venepuncture (90% of those aged <8 years, 83% of those aged 9-18 years and 73% of those aged >18 years). The perceived difficulty of collecting capillary blood samples did not affect success rate. CONCLUSIONS: Self-collected capillary blood sampling offers a feasible alternative to venous sampling, with the potential to facilitate autoantibody screening for Type 1 diabetes risk.

Urinary C-peptide creatinine ratio detects absolute insulin deficiency in Type 2 diabetes.

AIMS: To determine the prevalence and clinical characteristics of absolute insulin deficiency in long-standing Type 2 diabetes, using a strategy based on home urinary C-peptide creatinine ratio measurement. METHODS: We assessed the urinary C-peptide creatinine ratios, from urine samples taken at home 2 h after the largest meal of the day, in 191 insulin-treated subjects with Type 2 diabetes (diagnosis age ≥45 years, no insulin in the first year). If the initial urinary C-peptide creatinine ratio was ≤0.2 nmol/mmol (representing absolute insulin deficiency), the assessment was repeated. A standardized mixed-meal tolerance test with 90-min stimulated serum C-peptide measurement was performed in nine subjects with a urinary C-peptide creatinine ratio ≤ 0.2 nmol/mmol (and in nine controls with a urinary C-peptide creatinine ratio >0.2 nmol/mmol) to confirm absolute insulin deficiency. RESULTS: A total of 2.7% of participants had absolute insulin deficiency confirmed by a mixed-meal tolerance test. They were identified initially using urinary C-peptide creatinine ratio: 11/191 subjects (5.8%) had two consistent urinary C-peptide creatinine ratios ≤ 0.2 nmol/mmol; 9 of these 11 subjects completed a mixed-meal tolerance test and had a median stimulated serum C-peptide of 0.18 nmol/l. Five of these 9 had stimulated serum C-peptide <0.2 nmol/l and 9/9 subjects with urinary C-peptide creatinine ratio >0.2 had endogenous insulin secretion confirmed by the mixed-meal tolerance test. Compared with subjects with a urinary C-peptide creatinine ratio >0.2 nmol/mmol, those with confirmed absolute insulin deficiency had a shorter time to insulin treatment (median 2.5 vs. 6 years, P=0.005) and lower BMI (25.1 vs. 29.1 kg/m(2) , P=0.04). Two out of the five patients with absolute insulin deficiency were glutamic acid decarboxylase autoantibody-positive. CONCLUSIONS: Absolute insulin deficiency may occur in long-standing Type 2 diabetes, and cannot be reliably predicted by clinical features or autoantibodies. Absolute insulin deficiency in Type 2 diabetes may increase the risk of hypoglycaemia and ketoacidosis, as in Type 1 diabetes. Its recognition should help guide treatment, education and management. The urinary C-peptide creatinine ratio is a practical non-invasive method to aid detection of absolute insulin deficiency, with a urinary C-peptide creatinine ratio > 0.2 nmol/mmol being a reliable indicator of retained endogenous insulin secretion.

The impact of insulin administration during the mixed meal tolerance test.

AIMS: The mixed meal tolerance test is the gold standard measure of endogenous insulin secretion. Practical issues limit the routine clinical use of this test, including omitting insulin prior to the ingestion of a high-carbohydrate liquid mixed meal, which can result in marked hyperglycaemia. We aimed to assess whether insulin omission is necessary during the mixed meal tolerance test and whether fasting C-peptide was a practical alternative to the test. METHODS: Ninety-one adults with insulin-treated diabetes (Type 1 n = 56, Type 2 n = 35) underwent two mixed meal tolerance tests; one standard without insulin and one with the patient's usual morning insulin. RESULTS: The 90-min serum C-peptide was highly correlated in the standard mixed meal tolerance test and the test with insulin (r = 0.98, P < 0.0001). There was a 20% reduction in the peak C-peptide value when insulin was given {test with insulin [0.39 (0.01-1.16) vs. test without insulin 0.48 (0.01-1.36) nmol/l, P = 0.001]}, but the original serum C-peptide cut-off for significant endogenous insulin secretion (≥ 0.2 nmol/l) still correctly classified 90/91 patients (98% sensitivity/100% specificity). Fasting serum C-peptide was highly correlated to 90-min serum C-peptide during the test (r = 0.97, P < 0.0001). A fasting serum C-peptide ≥ 0.07 nmol/l was the optimal cut-off (100% sensitivity and 97% specificity) for significant endogenous insulin secretion (defined as 90-min stimulated serum C-peptide ≥ 0.2 nmol/l). CONCLUSIONS: Insulin omission may not always be necessary during a mixed meal tolerance test and fasting serum C-peptide may offer a practical alternative in insulin-treated patients.

Urine C-peptide creatinine ratio is an alternative to stimulated serum C-peptide measurement in late-onset, insulin-treated diabetes.

AIMS: Serum C-peptide measurement can assist clinical management of diabetes, but practicalities of collection limit widespread use. Urine C-peptide creatinine ratio may be a non-invasive practical alternative. The stability of C-peptide in urine allows outpatient or community testing. We aimed to assess how urine C-peptide creatinine ratio compared with serum C-peptide measurement during a mixed-meal tolerance test in individuals with late-onset, insulin-treated diabetes. METHODS: We correlated the gold standard of a stimulated serum C-peptide in a mixed-meal tolerance test with fasting and stimulated (mixed-meal tolerance test, standard home meal and largest home meal) urine C-peptide creatinine ratio in 51 subjects with insulin-treated diabetes (diagnosis after age 30 years, median age 66 years, median age at diagnosis 54, 42 with Type 2 diabetes, estimated glomerular filtration rate > 60 ml min(-1) 1.73 m(-2) ). RESULTS: Ninety-minute mixed-meal tolerance test serum C-peptide is correlated with mixed-meal tolerance test-stimulated urine C-peptide creatinine ratio (r = 0.82), urine C-peptide creatinine ratio after a standard breakfast at home (r = 0.73) and urine C-peptide creatinine ratio after largest home meal (r = 0.71). A stimulated (largest home meal) urine C-peptide creatinine ratio cut-off of 0.3 nmol/mmol had a 100% sensitivity and 96% specificity (area under receiver operating characteristic curve = 0.99) in identifying subjects without clinically significant endogenous insulin secretion (mixed-meal tolerance test-stimulated C-peptide < 0.2 nmol/l). In detecting a proposed serum C-peptide threshold for insulin requirement (stimulated serum C-peptide < 0.6 nmol/l), a stimulated (largest home meal) urine C-peptide creatinine ratio cut-off of 0.6 nmol/mmol had a sensitivity and specificity of 92%. CONCLUSION: In patients with insulin-treated diabetes diagnosed after age 30 years, urine C-peptide creatinine ratio is well correlated with serum C-peptide and may provide a practical alternative measure to detect insulin deficiency for use in routine clinical practice.

Law and public health at CDC.

Public health law is an emerging field in U.S. public health practice. The 20th century proved the indispensability of law to public health, as demonstrated by the contribution of law to each of the century's 10 great public health achievements. Former CDC Director Dr. William Foege has suggested that law, along with epidemiology, is an essential tool in public health practice. Public health laws are any laws that have important consequences for the health of defined populations. They derive from federal and state constitutions; statutes, and other legislative enactments; agency rules and regulations; judicial rulings and case law; and policies of public bodies. Government agencies that apply public health laws include agencies officially designated as "public health agencies," as well as health-care, environmental protection, education, and law enforcement agencies, among others.

Cranial nerve function in workers exposed to polychlorinated dioxins and furans.

OBJECTIVE: To look for possible effects of polychlorinated dioxins and furans (PCDD/F) on cranial nerve function. MATERIAL AND METHODS: Clinical and neurophysiological examinations [visual and brainstem auditory evoked potentials (VEP and BAEP), blink reflex] in 121 PCDD/F exposed workers of one pesticide producing plant. RESULTS: BAEP abnormalities were more frequent in workers with chloracne (6 of 33 workers, 18.2%) than in those without chloracne (7 of 84, 8.3%), but this was not statistically significant (chi2: 2.33). VEP abnormalities were seen in one worker with and two without chloracne. Clinically visual functions were normal except in one worker, who was amaurotic since birth. Blink reflex abnormalities without corresponding clinical findings were observed in two patients without chloracne. CONCLUSION: Severe exposure to PCDD/F is not followed by clinical signs of cranial nerve dysfunction but may create an increased risk for abnormal BAEP findings, which were more than twice as common in workers with chloracne. Although this difference did not reach statistical significance, it cannot exclude a toxic effect of PCDD/F, as statistical significance is difficult to achieve with such small numbers of workers. In none of the workers, BAEP abnormalities were accompanied by clinical signs of hearing dysfunction.

Group A streptococcal puerperal sepsis preceded by positive surveillance cultures.

BACKGROUND: Screening of pregnant women for vaginal and rectal carriage of group B streptococci may also identify group A streptococcal carriers. The clinical significance of prenatal group A streptococcal carriage is unknown. CASES: Two women developed group A streptococcal puerperal sepsis after delivery at one hospital 15 months apart. The first patient required hysterectomy and suffered complications including subcapsular hepatic hematoma, pleural effusion, and prolonged ileus. She recovered after a 35-day hospitalization. The second patient had endometritis and recovered. Both had had group A streptococci isolated from vaginal and rectal cultures taken for prenatal group B streptococcal screening. The acute sepsis isolates were both M-type 28, but pulsed-field gel electrophoresis determined that the strains were unrelated. CONCLUSIONS: Finding group A streptococci on prenatal culture may presage serious postpartum infection.

Risk factors for positive mantoux tuberculin skin tests in children in San Diego, California: evidence for boosting and possible foodborne transmission.

OBJECTIVES: Source case finding in San Diego, California, rarely detects the source for children with tuberculosis (TB) infection or disease. One third of all pediatric TB isolates in San Diego are Mycobacterium bovis, a strain associated with raw dairy products. This study was conducted to determine risk factors for TB infection in San Diego. DESIGN: Case-control study of children /=10 mm) Mantoux skin test (TST) were matched by age to 1 to 2 children with negative TST from the same clinic. We assessed risk factors for TB infection through parental interview and chart review. RESULTS: A total of 62 cases and 97 controls were enrolled. Eleven cases and 25 controls were excluded from analysis because of previous positive skin tests. Compared with controls, cases were more likely to have received BCG vaccine (73% vs 7%, odds ratio [OR] 44), to be foreign born (35% vs 11%, OR 4.3), and to have eaten raw milk or cheese (21% vs 8%, OR 3.76). The median time between the most recent previous TST and the current test was 12 months for cases and 25 months for controls. Other factors associated with a positive TST included foreign travel, staying in a home while out of the country, and having a relative with a positive TST. There was no association between contact with a known TB case. In a multivariable model, receipt of BCG, contact with a relative with a positive TST, and having a previous TST within the past year were independently associated with TB infection. CONCLUSIONS: We identified several new or reemerging associations with positive TST including cross border travel, staying in a foreign home, and eating raw dairy products. The strong associations with BCG receipt and more recent previous TST may represent falsely positive reactions, booster phenomena, or may be markers for a population that is truly at greater risk for TB infection. Unlike studies conducted in nonborder areas, we found no association between positive TB skin tests and contact with a TB case or a foreign visitor. Efforts to control pediatric TB in San Diego need to address local risk factors including consumption of unpasteurized dairy products and cross-border travel. The interpretation of a positive TST in a young child in San Diego who has received BCG is problematic.

Effect of short-course, high-dose amoxicillin therapy on resistant pneumococcal carriage: a randomized trial.

CONTEXT: Emerging drug resistance threatens the effectiveness of existing therapies for pneumococcal infections. Modifying the dose and duration of antibiotic therapy may limit the spread of resistant pneumococci. OBJECTIVE: To determine whether short-course, high-dose amoxicillin therapy reduces risk of posttreatment resistant pneumococcal carriage among children with respiratory tract infections. DESIGN AND SETTING: Randomized trial conducted in an outpatient clinic in Santo Domingo, Dominican Republic, October 1999 through July 2000. PARTICIPANTS: Children aged 6 to 59 months who were receiving antibiotic prescriptions for respiratory tract illness (n = 795). INTERVENTIONS: Children were randomly assigned to receive 1 of 2 twice-daily regimens of amoxicillin: 90 mg/kg per day for 5 days (n = 398) or 40 mg/kg per day for 10 days (n = 397). MAIN OUTCOME MEASURES: Penicillin-nonsusceptible Streptococcus pneumoniae carriage, assessed in nasopharyngeal specimens collected at days 0, 5, 10, and 28; baseline risk factors for nonsusceptible pneumococcal carriage; and adherence to regimen, compared between the 2 groups. RESULTS: At the day 28 visit, risk of penicillin-nonsusceptible pneumococcal carriage was significantly lower in the short-course, high-dose group (24%) compared with the standard-course group (32%); relative risk (RR), 0.77; 95% confidence interval (CI), 0.60-0.97; P =.03; risk of trimethoprim-sulfamethoxazole nonsusceptibility was also lower in the short-course, high-dose group (RR, 0.77; 95% CI, 0.58-1.03; P =.08). The protective effect of short-course, high-dose therapy was stronger in households with 3 or more children (RR, 0.72; 95% CI, 0.52-0.98). Adherence to treatment was higher in the short-course, high-dose group (82% vs 74%; P =.02). CONCLUSION: Short-course, high-dose outpatient antibiotic therapy appears promising as an intervention to minimize the impact of antibiotic use on the spread of drug-resistant pneumococci.

Observational study of the use of infection control interventions for Mycobacterium tuberculosis in pediatric facilities.

INTRODUCTION: Hospital transmission of Mycobacterium tuberculosis (TB) is a problem in US facilities where adults are treated. However, specific guidelines for facilities in which pediatric patients are cared for have never been defined, nor has any study attempted to assess pediatric health care worker (HCW) compliance with TB infection control (IC) guidelines. METHODS: An observational study was performed in two pediatric inpatient hospitals from May, 1996, to December, 1997. A trained observer tallied persons (i.e. professional HCWs, ancillary HCWs and non-HCWs) entering and leaving occupied TB isolation rooms and recorded adherence with IC practices (e.g. proper use of respirators, prompt door closures, door signage). RESULTS: Thirty children with confirmed or suspected TB were admitted during the study period and observed for a total of 242 h during which 656 visits by professional (n = 391) and ancillary (n = 131) HCWs and by family members (n = 134) were recorded. During 30% of visits doors remained open an average of 10 min, and during 20% of visits no respiratory protection was worn. In all, visitors wore the correct respiratory protection appropriately only 55% of the time. HCWs were more likely to wear respiratory protection when caring for children with a positive acid-fast bacillus smear than family members, but professional staff were no more likely than ancillary staff to do so. CONCLUSIONS: This is the first study to quantify compliance with IC practices for TB in pediatric hospitals. The majority of visitors entering TB isolation rooms occupied by children with confirmed or suspected TB complied with IC guidelines, but discrepancies were seen. Rather than relying on TB IC guidelines designed for adult facilities, guidelines specific for pediatric facilities that consider the local epidemiology of TB should be developed.

Principles of appropriate antibiotic use for treatment of acute respiratory tract infections in adults: background, specific aims, and methods.

The need to decrease excess antibiotic use in ambulatory practice has been fueled by the epidemic increase in antibiotic-resistant Streptococcus pneumoniae. The majority of antibiotics prescribed to adults in ambulatory practice in the United States are for acute sinusitis, acute pharyngitis, acute bronchitis, and nonspecific upper respiratory tract infections (including the common cold). For each of these conditions--especially colds, nonspecific upper respiratory tract infections, and acute bronchitis (for which routine antibiotic treatment is not recommended)--a large proportion of the antibiotics prescribed are unlikely to provide clinical benefit to patients. Because decreasing community use of antibiotics is an important strategy for combating the increase in community-acquired antibiotic-resistant infections, the Centers for Disease Control and Prevention convened a panel of physicians representing the disciplines of internal medicine, family medicine, emergency medicine, and infectious diseases to develop a series of "Principles of Appropriate Antibiotic Use for Treatment of Acute Respiratory Tract Infections in Adults." These principles provide evidence-based recommendations for evaluation and treatment of adults with acute respiratory illnesses.This paper describes the background and specific aims of and methods used to develop these principles. The goal of the principles is to provide clinicians with practical strategies for limiting antibiotic use to the patients who are most likely to benefit from it. These principles should be used in conjunction with effective patient educational campaigns and enhancements to the health care delivery system that facilitate nonantibiotic treatment of the conditions in question.

Principles of appropriate antibiotic use for treatment of nonspecific upper respiratory tract infections in adults: background.

The following principles of appropriate antibiotic use for adults with nonspecific upper respiratory tract infections apply to immunocompetent adults without complicating comorbid conditions, such as chronic lung or heart disease. 1. The diagnosis of nonspecific upper respiratory tract infection or acute rhinopharyngitis should be used to denote an acute infection that is typically viral in origin and in which sinus, pharyngeal, and lower airway symptoms, although frequently present, are not prominent. 2. Antibiotic treatment of adults with nonspecific upper respiratory tract infection does not enhance illness resolution and is not recommended. Studies specifically testing the impact of antibiotic treatment on complications of nonspecific upper respiratory tract infections have not been performed in adults. Life-threatening complications of upper respiratory tract infection are rare. 3. Purulent secretions from the nares or throat (commonly observed in patients with uncomplicated upper respiratory tract infection) predict neither bacterial infection nor benefit from antibiotic treatment.

Principles of appropriate antibiotic use for acute rhinosinusitis in adults: background.

The following principles of appropriate antibiotic use for adults with acute rhinosinusitis apply to the diagnosis and treatment of acute maxillary and ethmoid rhinosinusitis in adults who are not immunocompromised. Most cases of acute rhinosinusitis diagnosed in ambulatory care are caused by uncomplicated viral upper respiratory tract infections. Bacterial and viral rhinosinusitis are difficult to differentiate on clinical grounds. The clinical diagnosis of acute bacterial rhinosinusitis should be reserved for patients with rhinosinusitis symptoms lasting 7 days or more who have maxillary pain or tenderness in the face or teeth (especially when unilateral) and purulent nasal secretions. Patients with rhinosinusitis symptoms that last less than 7 days are unlikely to have bacterial infection, although rarely some patients with acute bacterial rhinosinusitis present with dramatic symptoms of severe unilateral maxillary pain, swelling, and fever. Sinus radiography is not recommended for diagnosis in routine cases. Acute rhinosinusitis resolves without antibiotic treatment in most cases. Symptomatic treatment and reassurance is the preferred initial management strategy for patients with mild symptoms. Antibiotic therapy should be reserved for patients with moderately severe symptoms who meet the criteria for the clinical diagnosis of acute bacterial rhinosinusitis and for those with severe rhinosinusitis symptoms-especially those with unilateral facial pain-regardless of duration of illness. For initial treatment, the most narrow-spectrum agent active against the likely pathogens, Streptococcus pneumoniae and Haemophilus influenzae, should be used.

Principles of appropriate antibiotic use for acute pharyngitis in adults: background.

The following principles of appropriate antibiotic use for adults with acute pharyngitis apply to immunocompetent adults without complicated comorbid conditions, such as chronic lung or heart disease, and history of rheumatic fever. They do not apply during known outbreaks of group A streptococcus. 1. Group A beta-hemolytic streptococcus (GABHS) is the causal agent in approximately 10% of adult cases of pharyngitis. The large majority of adults with acute pharyngitis have a self-limited illness, for which supportive care only is needed. 2. Antibiotic treatment of adult pharyngitis benefits only those patients with GABHS infection. All patients with pharyngitis should be offered appropriate doses of analgesics and antipyretics, as well as other supportive care. 3. Limit antibiotic prescriptions to patients who are most likely to have GABHS infection. Clinically screen all adult patients with pharyngitis for the presence of the four Centor criteria: history of fever, tonsillar exudates, no cough, and tender anterior cervical lymphadenopathy (lymphadenitis). Do not test or treat patients with none or only one of these criteria, since these patients are unlikely to have GABHS infection. For patients with two or more criteria the following strategies are appropriate: (a) Test patients with two, three, or four criteria by using a rapid antigen test, and limit antibiotic therapy to patients with positive test results; (b) test patients with two or three criteria by using a rapid antigen test, and limit antibiotic therapy to patients with positive test results or patients with four criteria; or (c) do not use any diagnostic tests, and limit antibiotic therapy to patients with three or four criteria. 4. Throat cultures are not recommended for the routine primary evaluation of adults with pharyngitis or for confirmation of negative results on rapid antigen tests when the test sensitivity exceeds 80%. Throat cultures may be indicated as part of investigations of outbreaks of GABHS disease, for monitoring the development and spread of antibiotic resistance, or when such pathogens as gonococcus are being considered. 5. The preferred antibiotic for treatment of acute GABHS pharyngitis is penicillin, or erythromycin in a penicillin-allergic patient.

Principles of appropriate antibiotic use for treatment of uncomplicated acute bronchitis: background.

The following principles of appropriate antibiotic use for adults with acute bronchitis apply to immunocompetent adults without complicating comorbid conditions, such as chronic lung or heart disease. The evaluation of adults with an acute cough illness or a presumptive diagnosis of uncomplicated acute bronchitis should focus on ruling out serious illness, particularly pneumonia. In healthy, nonelderly adults, pneumonia is uncommon in the absence of vital sign abnormalities or asymmetrical lung sounds, and chest radiography is usually not indicated. In patients with cough lasting 3 weeks or longer, chest radiography may be warranted in the absence of other known causes. Routine antibiotic treatment of uncomplicated acute bronchitis is not recommended, regardless of duration of cough. If pertussis infection is suspected (an unusual circumstance), a diagnostic test should be performed and antimicrobial therapy initiated. Patient satisfaction with care for acute bronchitis depends most on physician--patient communication rather than on antibiotic treatment.

Principles of appropriate antibiotic use for treatment of acute respiratory tract infections in adults: background, specific aims, and methods.

The need to decrease excess antibiotic use in ambulatory practice has been fueled by the epidemic increase in antibiotic-resistant Streptococcus pneumoniae. The majority of antibiotics prescribed to adults in ambulatory practice in the United States are for acute sinusitis, acute pharyngitis, acute bronchitis, and nonspecific upper respiratory tract infections (including the common cold). For each of these conditions-especially colds, nonspecific upper respiratory tract infections, and acute bronchitis (for which routine antibiotic treatment is not recommended)-a large proportion of the antibiotics prescribed are unlikely to provide clinical benefit to patients. Because decreasing community use of antibiotics is an important strategy for combating the increase in community-acquired antibiotic-resistant infections, the Centers for Disease Control and Prevention convened a panel of physicians representing the disciplines of internal medicine, family medicine, emergency medicine, and infectious diseases to develop a series of "Principles of Appropriate Antibiotic Use for Treatment of Acute Respiratory Tract Infections in Adults." These principles provide evidence-based recommendations for evaluation and treatment of adults with acute respiratory illnesses.This paper describes the background and specific aims of and methods used to develop these principles. The goal of the principles is to provide clinicians with practical strategies for limiting antibiotic use to the patients who are most likely to benefit from it. These principles should be used in conjunction with effective patient educational campaigns and enhancements to the health care delivery system that facilitate nonantibiotic treatment of the conditions in question.