Physician practice patterns: chest x-ray ordering for the evaluation of acute cough illness in adults

Radiographic Imaging of Community-Acquired Pneumonia: A Case-Based Review

The chest radiograph is the most common imaging examination performed in most radiology departments, and one of the more common indications for these studies is suspected infection. Radiologists must therefore be aware of less common radiographic patterns of pulmonary infection if they are to add value in the interpretation of chest radiographs for this indication. This review uses a case-based format to illustrate a range of imaging findings that can be associated with acute pulmonary infection and highlight findings that should prompt investigation for diseases other than community-acquired pneumonia to prevent misdiagnosis and delays in appropriate management.

ACR Appropriateness Criteria® Acute Respiratory Illness in Immunocompetent Patients

Acute respiratory illness, defined as cough, sputum production, chest pain, and/or dyspnea (with or without fever), is a major public health issue, accounting for millions of doctor office and emergency department visits every year. While most cases are due to self-limited viral infections, a significant number of cases are due to more serious respiratory infections where delay in diagnosis can lead to morbidity and mortality. Imaging plays a key role in the initial diagnosis and management of acute respiratory illness. This study reviews the current literature concerning the appropriate role of imaging in the diagnosis and management of the immunocompetent adult patient initially presenting with acute respiratory illness. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

[Community-acquired pneumonia]

CLINICAL ISSUE

The diagnosis of community-acquired pneumonia (CAP) is often not possible based only on the clinical symptoms and biochemical parameters.

STANDARD RADIOLOGICAL METHODS

For every patient with the suspicion of CAP, a chest radiograph in two planes should be carried out. Additionally, a risk stratification for the decision between outpatient therapy or hospitalization is recommended.

METHODICAL INNOVATIONS

Based on the evaluation of the different radiological patterns as well as their extent and distribution, a rough allocation to so-called pathogen groups as well as a differentiation between viral and bacterial infections are possible; however, because different pathogens cause different patterns an accurate correlation is not feasible by relying purely on imaging.

ACHIEVEMENTS/PRACTICAL RECOMMENDATIONS

The radiological findings serve as proof or exclusion of pneumonia and can also be used to evaluate the extent of the disease (e.g. monolobular, multilobular, unilateral or bilateral). In cases of prolonged disease, suspicion of complications (e.g. pleural effusion or empyema, necrotizing pneumonia or abscess) or comorbid conditions (e.g. underlying pulmonary or mediastinal diseases) computed tomography is an important diagnostic tool in addition to chest radiography. Ultrasound is often used to diagnose pleural processes (e.g. parapneumonic effusion or pleural empyema).

Clinical and Laboratory Findings in Patients With Acute Respiratory Symptoms That Suggest the Necessity of Chest X-ray for Community-Acquired Pneumonia

Background:

Pneumonia is a common illness in all parts of the world and is considered as a major cause of death among all age groups. Nevertheless, only about 5% of patients referring to their primary care physicians with acute respiratory symptoms will develop pneumonia.

Objectives:

This study was performed to derive practical criteria for performing chest radiographs for the evaluation of community-acquired pneumonia (CAP).

Patients and Methods:

A total of 420 patients with acute respiratory symptoms and positive findings on chest radiograph were evaluated from December 2008 to December 2009. The subjects were referred to outpatient clinics or emergency departments of Birjand's medical university hospitals, Iran, and were enrolled as positive cases. A checklist was completed for each patient including their demographic information, clinical signs and symptoms (cough, sputum production, dyspnea, chest pain, fever, tachycardia, and tachypnea), abnormal findings in pulmonary auscultation and laboratory findings (erythrocyte sedimentation rate, C-reactive protein levels, and white blood cell count). An equal number of age-matched individuals with acute respiratory symptoms, but insignificant findings on chest radiography, were included as the control group. Finally, the diagnostic values of different findings were compared.

Results:

The data showed that vital signs and physical examination findings are useful screening parameters for predicting chest radiograph findings in outpatient settings. Therefore, by implementing a prediction rule, we would be able to determine which patients would benefit from a chest X-Ray (sensitivity, 94% and specificity, 57%).

Conclusions:

This study's findings suggest that requesting chest radiographs might not be necessary in patients with acute respiratory symptoms unless the vital signs and/or physical examination findings are abnormal. Considering the 94% sensitivity of this rule for predicting CAP, a chest radiograph is required for patients with unreliable follow-ups or moderate to high likelihood of morbidity if CAP is not initially detected.

Diagnosis and management of pneumonia and bronchitis in outpatient primary care practices

AIMS

To understand which clinical criteria physicians use to diagnose pneumonia compared to bronchitis and upper respiratory tract infection (URTI).

METHODS

Retrospective chart review of adults diagnosed with pneumonia, bronchitis, or URTI.

RESULTS

Logistic regression analysis identified rales, a temperature > 100 degrees F (37.8 degrees C), chest pain, dyspnoea, rhonchi, heart rate, respiratory rate, and rhinorrhoea, as the best explanation for the variation in diagnosis of pneumonia compared to either of the alternative diagnoses (R2 = 59.3), with rales and a temperature > 100 degrees F explaining 30% of the variation. Rales, chest pain, and a temperature > 100 degrees F best predicted the ordering of a chest x-ray (R2 = 20.0). However, 35% (59/175) of patients diagnosed with pneumonia had a negative chest x-ray. Abnormal breath sounds were the best predictors for prescribing antibiotics (R2 = 38%). A significant number of patients with acute bronchitis (93% excluding sinusitis) and URTI (42%) were given antibiotics.

CONCLUSIONS

The presence of abnormal breath sounds and a temperature > 100 degrees F were the best predictors of a diagnosis of pneumonia.

ACR Appropriateness Criteria on acute respiratory illness

In a patient with acute respiratory illness (cough, sputum production, chest pain, and/or dyspnea), the need for chest imaging depends on the severity of illness, age of the patient, clinical history, physical and laboratory findings, and other risk factors. Chest radiographs seem warranted when one or more of the following are present: age ≥ 40; dementia; a positive physical examination; hemoptysis; associated abnormalities (leukocytosis, hypoxemia); or other risk factors, including coronary artery disease, congestive heart failure, or drug-induced acute respiratory failure. Chest CT may be warranted in complicated cases of severe pneumonia and in febrile neutropenic patients with normal or nonspecific chest radiographic findings. Literature on the indications and usefulness of radiologic studies for acute respiratory illness in different clinical settings is reviewed.

The Current State of Cough Research: The Clinician’s Perspective

Cough is one of the most common reasons for medical consultation and it is responsible for a large human and socioeconomic burden. Current guidelines provide a useful framework for cough management and summarize current knowledge of causes and optimal testing sequences and treatments of cough. However, research is needed on the role of noninvasive airway inflammation measurement in assessing etiology; optimal treatment of postinfectious cough or cough due to gastroesophageal reflux disease; protussive treatment; causes of chronic cough in immunocompromised hosts; and characteristics and management of psychogenic cough. The effects of the use or nonuse of evidence-based guidelines should be documented. An empiric, integrative approach to management of chronic cough also needs further validation.