Conventional bronchoscopy vs. endosonography:
A randomized prospective clinical study for the diagnosis of sarcoidosis

Sarcoidosis is the most prevalent interstitial lung disease in Western-Europe
and the US. The disease is most prevalent in young adults. To set the final
diagnosis of sarcoidosis, the following parameters need to be present:

1. A clinical and radiological suspicion of sarcoidosis
2. A tissue diagnosis of disease-specific non-caseating granulomas.
3. Exclusion of possible alternative diagnoses as lung cancer or tuberculosis.

Nowadays, a bronchoscopy with lung biopsies is advised to set a tissue
diagnosis of sarcoidosis. However, these biopsies are only diagnostic in 70% of
the procedures and they are associated with a 3% risk of coughing up blood and
a 4% risk of a lung collaps.

Since recently, a new diagnostic procedure has come available. This procedure,
endo-sonography, makes it possible to biopsy lymph nodes in the chest under
direct visualisation and has a diagnostic accuracy of 85%. The associated risk
of complications appears to be small (<1%)

We consider the current standard for the diagnostics of sarcoidosis to be
outdated, considering the clinical availability of endo-sonography. We expect
that endo-sonography is more frequent diagnostic for a tissue diagnosis of
sarcoidosis.
Also we hypothesize that this technique is safer and more preferred by
patients.

The study is a diagnostic study for the diagnostics of sarcoidosis, in where a
new, endo-sonographic procedure is compared to the current, bronchoscopic
method.
The objective is to assess the accuracy, safety and patient tolerance of
endo-sonography against conventional bronchoscopy for the diagnosis of
sarcoidosis.

For the detection of non-caseating granulomas, patients are randomized between
endo-sonography and conventional bronchoscopy. In both study arms, a lung
lavage (BAL) will be performed as well. Specific BAL outcomes can also
contribute to the diagnosis of sarcoidosis.

After endo-sonography or bronchoscopy, the contribution of both methods for the
detection of non-caseating granulomas and for the diagnosis of sarcoidosis will
be evaluated.

After 6 months follow-up, all patients will be seen again by the treating
physician.

Since all procedures are part of standard clinical care, the are no additional
risks attached to the study.
Prior to the investigation, patients are informed about the risks of the
procedures.

The patients are subjected to a small questionaire and a visual analogue scale
(VAS) to determine the procedure demand for the patient. The VAS quantification
and the questionaire will take approximately 10 minutes.