Diagnosing pneumonia in patients with acute cough: clinical judgment compared to chest radiography

Pneumonia is often diagnosed and treated empirically, but the accuracy of clinical assessment alone is largely unknown. We therefore set out to determine the diagnostic accuracy of clinical judgment based on signs and symptoms to detect radiographic pneumonia in patients presenting with acute cough in primary care.In 2810 patients consulting with acute cough in 12 European countries, general practitioners (GPs) recorded whether they considered pneumonia present (“yes” or “no”) immediately after the history and physical examination. Chest radiography was performed within one week by local radiologists blind to other patient characteristics.140 patients had radiographic pneumonia (5%), of whom 41 (29%) had been diagnosed as such by the GP. GPs diagnosed pneumonia in 31 (1%) patients on clinical grounds who turned out not to have radiographic pneumonia (n=2670). In patients diagnosed with pneumonia by GPs on clinical grounds alone, 57% were subsequently diagnosed with radiographic pneumonia (positive predictive value, PPV). Negative predictive value (NPV), sensitivity and specificity of GPs' clinical judgment were 96%, 29% and 99% respectively. Patients with radiographic pneumonia, but who had not been diagnosed empirically by GPs, presented with less severe symptoms compared to patients with a clinical diagnosis of pneumonia (p<0.05).The predictive values of GPs' clinical judgment, particularly the high NPV's, are helpful in routine care. Nonetheless, the majority of diagnoses of radiographic pneumonias was not suspected on clinical grounds. There is a need to further support the detection of clinically relevant pneumonia in primary car