Whooping Cough (Pertussis) - Exams and Tests
A doctor considers the following when
making a preliminary diagnosis of
whooping cough (pertussis):
Symptoms. A doctor may suspect whooping cough when a person
has recently had cold symptoms and a dry, hacking cough that progresses to
bursts of uncontrollable, often violent coughing that may make it temporarily
impossible to breathe. Fever, sore
throat, and wheezing are usually absent or very mild with whooping cough. When
present, these symptoms can help a doctor distinguish between whooping cough
and other conditions with similar symptoms, such as a cold or
Immunization status. An important consideration when making a preliminary diagnosis of
whooping cough (pertussis) is whether a person's immunizations against
pertussis are up to date.
Community outbreaks. Whooping cough may be suspected when other cases of whooping
cough have recently been reported within the local community.
To diagnose whooping cough, doctors may test
mucus from the nasopharynx region, which is where
nasal passages meet the back of the throat. To collect a mucus sample, doctors
may pass a swab or suction tube deep into the back of the nose. The sample can
be tested by
culture. It is the most accurate method, but it takes
10 to 14 days to get the results. Polymerase chain reaction (PCR) is often used
along with culture to get test results within several days. PCR detects the
genetic material (DNA) of whooping cough bacteria.
The doctor may do more than one test to find out if you or your child has whooping cough. Treatment will usually start right away if your doctor strongly suspects
whooping cough as a cause of the symptoms.
Other tests may be done to rule out other
problems, to monitor the person's condition, or to find out whether
complications have developed.
complete blood count or other blood tests may be done
to help rule out other diseases.
X-rays may be done, especially in infants. Although
X-ray images often appear normal in whooping cough, they may be needed to rule
out other possible causes of symptoms or to find out whether
complications, such as
pneumonia, have developed.
pulse oximeter may be used to check the blood oxygen
levels, which helps a doctor monitor how well the lungs are working and decide
what treatments to use.