Prevalence of Spontaneous Pneumothorax in BHD

Study Overview
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Brief Summary
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To assess the prevalence of BHD (Birt-Hogg-Dubé syndrome) among patients with spontaneous pneumothorax. Patients who were treated for primary spontaneous pneumothorax in Rijnstate hospital are to be included. Patients will receive a questionnaire. When given consent, the investigators will invite them for a one-time visit to the out-patient clinic. Patients will be asked for a blood sample to determine pathogenic FLCN (folliculin) mutations and a pulmonary CT scan for evaluation of presence of lung cysts.

Detailed Description
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Based on the results of the pilot study in VUmc *Free University Medical Center), in which 3 out of 40 tested patients had a pathological FLCN mutation, the investigators decided to extend the study to a second center; Rijnstate Hospital Arnhem. In this hospital a retrospective search was performed; patients who were treated for primary spontaneous pneumothorax were included. In the dossiers the investigators searched for medical history, pneumothorax side and recurrence, diagnostic imaging, treatment, co-morbidity, complications of treatment, skin abnormalities, kidney disease, smoking behavior, medication, and familial incidence of pneumothorax and other diseases. Patients will receive a letter with explanation of the research and a questionnaire in which the investigators ask them their about the medical status, co-morbidity, pneumothorax (number and side), smoking behavior, use of drugs, familial incidence of pneumothorax and other diseases. The population will be formed out of patients who have returned the fully filled in questionnaire and who have given permission to receive information for further research. This further information will consist of an information letter on BHD syndrome and a consent form for a one-time visit to the out-patient clinic of Rijnstate hospital. Investigators expect that about 200 patients will return the fully filled in questionnaire and give their consent for further research. In a one-time visit in out-patient clinic, there will be given personal information on BHD syndrome and there will be performed physical examination for finding fibrofolliculomas. A pulmonary CT scan for evaluation of presence of lung cysts will be performed. Two samples of venous blood will be collected to access information on DNA diagnostics for pathogenic FLCN mutations. These are associated with the BHD syndrome. This last diagnostic testing will be performed in VUmc (Vrije Universiteit medisch centrum or Free University Medical Centre).

Official Title
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Prevalence of Birt-Hogg-Dubé Syndrome Among Patients With (Hereditary) Spontaneous Pneumothorax

Conditions
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Spontaneous Pneumothorax

Intervention / Treatment
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* Radiation: CT scan of the thorax
* Genetic: blood sample for FLCN mutation analyses


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: treated in Rijnstate hospital for primary spontaneous pneumothorax informed consent Exclusion Criteria: secondary or iatrogenic pneumothorax

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Screening
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Spontaneous pneumothorax patients 1<br>Patients who were treated for spontaneous pneumothorax in Rijnstate hospital. Interventions: visit to out-patient clinic,CT scan of pulmones. | Radiation: CT scan of the thorax<br>* A low dose CT scan of the thorax (2mSv) wil be performed once.<br>Genetic: blood sample for FLCN mutation analyses<br>* A venous punction in order to withdraw 16ml blood is undertaken once.<br>|
| Active Comparator: Spontaneous pneumothorax patients 2<br>Patients who were treated for spontaneous pneumothorax in Rijnstate hospital. Interventions: withdrawal of blood sample for DNA analyses, | Radiation: CT scan of the thorax<br>* A low dose CT scan of the thorax (2mSv) wil be performed once.<br>Genetic: blood sample for FLCN mutation analyses<br>* A venous punction in order to withdraw 16ml blood is undertaken once.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| presence of pathogenic FLCN mutations | by assessing blood samples | 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| presence of lung cysts | visible on pulmonary low dose CT | 6 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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spontaneous pneumothorax, familial pneumothorax, Birt-Hogg-Dube syndrome, prevalence, FLCN mutation, Lung cysts, BHD, inherited disease, genetic disease, primary pneumothorax, CAT scan, CT scan