The doctor will consider the symptoms and perform a physical examination. When there is inflammation in the lungs, auscultation may reveal diminished breath sounds or a fine wet rhotic sound. Blood tests or other tests may be done to look for white blood cell counts or other abnormalities that may be caused by the infection. A chest x-ray is often needed to show the area or extent of the pneumonia. In some cases, a more precise CT scan may be needed. In addition, sputum (coughed up from the lungs) cultures or tests may sometimes be performed to see if bacteria or viruses can be found. Patients who need to be hospitalized often need more of these tests for their most likely viruses and bacteria. If the patient is not improving, has a serious infection, or is at high risk for rare infections, he or she may also need to have a sputum specimen collected from the lungs through a procedure called fiberoptic bronchoscopy.