Pneumonia can affect anyone but children people with chronic lung disease or older adults are more commonly affected. The life-threatening condition caused mostly by bacteria is often mistaken for cold or flu. Early diagnosis can help in the treatment and save lives. Your doctor will suspect pneumonia if your medical history and physical examination give some clues. Read to find out what the 8 common signs and symptoms of pneumonia are. A stethoscope assesses your breathing quality. The presence of wheezing bubbling or cracking sounds will prompt your doctor to order the following tests to confirm the diagnosis of pneumonia.