Diagnosis of respiratory tract infections by molecular techniques in pediatric patients

Acute respiratory infections are one of the most important reasons for
hospitalisation of young children. This is not only an important cause of
morbidity for patients, but it also causes substantial health care expenses due
to hospitalisation, diagnostic procedures and therapy.
In a lot of cases a causing pathogen is not found, due to lack of sensitivity
of culture and serology or lack of adequate samples for diagnostic testing.
This may result in suboptimal treatment and longer hospitalisation. More
sensitive and rapid testing is needed to increase pathogen detection rates so
adequate treatment can be given.

Goal of this study is to obtain more insight into causative agents of
respiratory tract infections in children using molecular techniques and how
results of molecular test should be interpretated in relation to clinical
symptoms. The optimal clinical material for molecular testing will be assessed
as well.

Key questions are:
- What is the frequency of the different pathogens when molecular test are used.
- Are there associations with clinical features?
- What is the best way of sampling for molecular tests?
- Is there a correlation between the amount (= load) of a pathogen and the
clinical picture.
- What is the meaning of multiple postive test, for different pathogens, with
this sensitive test.
- How long can DNA/RNA be detected after the onset of symptoms, with and
without treatment.

This study will be carried out in two different hospitals.
Parents of children suspected of respirator tract infection will be asked to
participate in the study. After informed consent, different respiratory tract
materials will be obtained (nasopharyngeal wash, nasopharyngeal swab, pharynx
swab and a urine sample). If blood is drawn from a patient for routine
diagnostic purpose, an additional 2 ml will be taken to test for (invasive)
respiratory pathogens. If patients are still in the hospital on day 3 and 7,
nasopharyngeal wash, nasopharyngeal swab and pharynx swab will be repeated.
Nurses specialised in children care will perform the sampling procedures. The
treating physician shall ask for informed consent and will fill in the case
record form. The principle investigator will visit the wards and help when
there are questions or difficulties.
Results will be correlated to clinical symptoms. Sample methods will be
compared with each other.
This study will last 2 years to include a total of 300 patients.

The nature and extent of the burden exists of:

1) An unpleasant sensation during the sampling of nasopharyngeal samples.
2) Urine sampling with urine bag sticked to skin can give some irritation
during removel, comparble with the removel a plaster.

If a diagnosis of an atypical bacteria or virus is confirmed antibiotics can
by revised or stopped. This will be beneficial to the patient.