URTObstruction - Diseases
Introduction Physical Examination Differential Diagnosis Specific Diseases Epiglottitis Viral croup Clinical Treatment Other types Foreign body aspiration Retropharyngeal abscess References Other Lectures		Viral croup is usually a benign, self-limited disease. It is responsible for more than 90% of cases of stridor outside the neonatal period. The typical age range is 6 months to 3 years, although it can be seen up to the age of 12. The etiology is almost always viral, usually parainfluenza virus. The male:female ratio is 1, although severe croup is more common in boys. The typical history is 2 to 3 days of a URI with a gradually worsening cough, especially at night. By the third or fourth day, there is a barking cough, stridor and dyspnea, as well as varying degrees of anxiety and fever. Physical exam reveals marked stridor, retractions, tachypnea, hoarseness and mild cyanosis in room air. Stridor is typically biphasic, although the inspiratory component is usually much greater than the expiratory component. The patient may be fairly calm with little distress until the examiner begins, at which time the patient's anxiety will increase markedly, causing a worsening of the stridor. The typical case of croup can be differentiated from epiglottitis on clinical grounds, so xrays are not necessary in every patient. In fact, in mild croup, xrays are usually normal. In the more severely ill child, however, xrays not only serve to establish the diagnosis, but also to rule out other conditions, such as epiglottitis. Because the diagnosis of croup is clinical, laboratory tests are generally unnecessary. Return to top of page