title: Risk of spontaneous pneumothorax due to air travel and diving in patients with Birt-Hogg-Dubé syndrome.
abstract: OBJECTIVE
  Birt-Hogg-Dubé syndrome is an autosomal dominant disorder characterized by skin fibrofolliculomas, lung cysts, spontaneous pneumothorax and renal cell cancer due to germline folliculin (FLCN) mutations (Menko et al. in Lancet Oncol 10(12):1199-1206, 2009). The aim of this study was to evaluate the incidence of spontaneous pneumothorax in patients with BHD during or shortly after air travel and diving.
  
  
  METHODS
  A questionnaire was sent to a cohort of 190 BHD patients and the medical files of these patients were evaluated. The diagnosis of BHD was confirmed by FLCN mutations analysis in all patients. We assessed how many spontaneous pneumothoraces (SP) occurred within 1 month after air travel or diving.
  
  
  RESULTS
  In total 158 (83.2 %) patients returned the completed questionnaire. A total of 145 patients had a history of air travel. Sixty-one of them had a history of SP (42.1 %), with a mean of 2.48 episodes (range 1-10). Twenty-four (35.8 %) patients had a history of pneumothorax on both sides. Thirteen patients developed SP < 1 month after air travel (9.0 %) and two patients developed a SP < 1 month after diving (3.7 %). We found in this population of BHD patients a pneumothorax risk of 0.63 % per flight and a risk of 0.33 % per episode of diving. Symptoms possible related to SP were perceived in 30 patients (20.7 %) after air travel, respectively in ten patients (18.5 %) after diving.
  
  
  CONCLUSIONS
  Based on the results presented in this retrospective study, exposure of BHD patients to considerable changes in atmospheric pressure associated with flying and diving may be related to an increased risk for developing a symptomatic pneumothorax. Symptoms reported during or shortly after flying and diving might be related to the early phase of pneumothorax. An individualized advice should be given, taking also into account patients' preferences and needs.
authors.affiliation: Department of Pulmonary Diseases, VU University Medical Center, PO Box 7057, 1007 MB Amsterdam, The Netherlands.
authors.forename: P C
authors.initials: PC
authors.lastname: Johannesma
authors.affiliation: Department of Clinical Genetics, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: I
authors.initials: I
authors.lastname: van de Beek
authors.affiliation: Department of Pulmonary Diseases, VU University Medical Center, PO Box 7057, 1007 MB Amsterdam, The Netherlands.
authors.forename: J W T
authors.initials: JW
authors.lastname: van der Wel
authors.affiliation: Department of Thoracic Surgery, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: M A
authors.initials: MA
authors.lastname: Paul
authors.affiliation: Department of Clinical Genetics, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: A C
authors.initials: AC
authors.lastname: Houweling
authors.affiliation: Department of Epidemiology and Biostatistics, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: M A
authors.initials: MA
authors.lastname: Jonker
authors.affiliation: Department of Radiology, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: J H T M
authors.initials: JH
authors.lastname: van Waesberghe
authors.affiliation: Department of Radiology, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: R
authors.initials: R
authors.lastname: Reinhard
authors.affiliation: Department of Dermatology, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Th M
authors.initials: TM
authors.lastname: Starink
authors.affiliation: Department of Urology, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: R J A
authors.initials: RJ
authors.lastname: van Moorselaar
authors.affiliation: Family Cancer Clinic, Netherlands Cancer Institute, Amsterdam, The Netherlands.
authors.forename: F H
authors.initials: FH
authors.lastname: Menko
authors.affiliation: Clatterbridge Cancer Centre, Liverpool Heart and Chest Hospital, Liverpool, UK ; Department of Thoracic Oncology, University of Liverpool, Liverpool, UK.
authors.forename: P E
authors.initials: PE
authors.lastname: Postmus
keywords: Air travel; Birt–Hogg–Dubé syndrome; Diving; FLCN; Folliculin; Lung cysts; Renal cell cancer; Spontaneous pneumothorax; Thoracic computed tomography