complications of pneumonia, such as empyema or abscess, and in those in whom the diagnosis is in question A chest radiograph is also warranted in patients with unexplained cough, or significant or persistent pulmonary signs In children with an uncomplicated exacerbation of their asthma, a radiograph is unnecessary Inspiratory and expiratory or decubitus films have traditionally been recommended if a radiolucent foreign body is suspected; however, these studies have been found to have only fair-to-moderate sensitivity and specificity and thus their clinical utility is unknown If the suspicion for aspiration is high based on history and examination, bronchoscopy may be warranted without additional imaging beyond standard radiographs to identify radiopaque foreign bodies (see Chapter 32 Foreign Body: Ingestion and Aspiration ) All patients with hemoptysis should have chest radiographs performed Chest computed tomography is indicated in patients with persistent or moderate-to-severe hemoptysis, particularly if chest radiographs are normal Other studies that could be useful in selected patients include lateral neck radiographs, barium swallow, and computed tomography of the sinuses, neck, or chest Laboratory testing for a patient presenting to the emergency department with cough is not routinely warranted, though may be useful or necessary for specific diagnoses In the case of pneumonia, blood cultures should only be obtained in those hospitalized with moderate-to-severe disease, complicated pneumonia, failure to improve after 48 to 72 hours of antibiotic therapy, immunosuppressed patients or those with indwelling catheters with fever (see Pneumonia, Community-Acquired Pathway, https://www.chop.edu/clinicalpathway/pneumonia-community-acquired-clinical-pathway ) Additional tests for use in specific circumstances include a complete blood count and differential, tuberculin test, nasopharyngeal swab for rapid assays (commonly respiratory syncytial virus, and influenza), pertussis testing, and sputum culture and Gram stain (neutrophils and gram-positive diplococci with pneumococcal pneumonia) in those old enough to produce an adequate sample Pulmonary function testing can be useful to diagnose or follow obstructive airway disease In cases of airway masses, airway anomalies, foreign bodies, or atypical pneumonias, bronchoscopy may be necessary Approach The magnitude of a child’s respiratory distress is the most immediate concern for any child who presents with cough Any child with significant respiratory distress needs immediate attention to address their oxygenation and ventilation If not in significant distress, the next consideration is whether the onset of the cough is acute or chronic If acute in onset, the major considerations in the evaluation, as