[Diagnosis in acute bronchiolitis. Review of the evidence for the consensus conference on acute bronchiolitis].

A review of the evidence on the most commonly used diagnostic procedures in acute bronchiolitis is presented. Rapid diagnostic tests for respiratory syncytial virus infection are acceptably valid. These tests show a moderate to high sensitivity and a high specificity in relation to other reference tests. The tests most commonly used, due to their low complexity and rapid performance (enzyme immunoassay, immunochromatography and optical immunoassay techniques), have lower sensitivity than immunofluorescence. With these, a positive result is valid, but a negative result does not exclude the presence of infection with sufficient certainty. Respiratory specimens obtained by nasopharyngeal aspirate are the most valid for the identification of respiratory syncytial virus. The usefulness of chest radiography in the management of bronchiolitis has not been demonstrated. There is an unfavourable risk-benefit ratio due to the ionizing radiation exposure. There are no specific signs or symptoms to identify patients who will benefit from performing a chest radiograph. The measurement of oxygen saturation is useful in the initial assessment or in the monitoring of clinical changes of patients. Patients with AB have a very low risk of concurrent bacterial infection (particularly urinary tract infection), so the routine use of screening tests for bacterial infection is not useful. There are no clinical criteria with sufficient predictive capacity to select cases that would benefit from such tests.