Severe respiratory infection in a child

Late at night a young 10-year-old patient (25 kg) is admitted to the ER (hospital with complex cardiovascular centre), accompanied by his parents. The patient presented with a dry irritating cough, he is subfebrile and exhausted from the cough. The patient is complaining of headache and loss of appetite. He has been in this condition for two days.
You’ve decided to measure the CRP level.
What will be your next step?
10
years
25
kg
RR
16 /min
HR
90 /min
BP
110/70 (83) mmHg
temperature
37 °C
Examination
The patient is alert, oriented, with no significant change in breath sounds.
Inflammatory markers
CRP
28 mg/L
Inflammatory markers
Take a sample