Pleural Covering Application for Recurrent Pneumothorax in a Patient with Birt-Hogg-Dubé Syndrome

Birt-Hogg-Dubé Syndrome: A Review of Dermatological Manifestations and Other Symptoms

Birt-Hogg-Dubé syndrome (BHD) is an autosomal dominant genodermatosis with malignant potential characterized by cutaneous and extracutaneous stigmata. Aberrations in the folliculin (FLCN) gene, which is located on chromosome 17, have been discovered in individuals with this condition. Over 150 unique mutations have been identified in BHD. The skin lesions associated with this condition include fibrofolliculomas, trichodiscomas, perifollicular fibromas, and acrochordons. Extracutaneous features of the syndrome typically include the lung (spontaneous pneumothorax and cysts) and the kidney (neoplasms). The only malignancies associated with BHD are renal cancers; however, other tumors have been observed in individuals with BHD. In this article, the skin lesions associated with this condition are reviewed, lung and renal manifestations associated with this syndrome are presented, and malignancies occurring in these patients are summarized.

Recurrent renal cancer in Birt-Hogg-Dubé syndrome: A case report

INTRODUCTION

Birt-Hogg-Dubé syndrome (BHDS) is a rare autosomal dominant disease. It is caused by constitutional mutations in the FLCN gene. Since BHDS is a rare syndrome therefore it is unknown to many physicians. However, it is important to identify this rare syndrome at early stages because incidence of renal cancer in BHD patients is very high and its detection at early stages can prevent its metastasis. Hence, we want to present a case of BHDS and draw the attention of the treating physician to this rare inherited disorder and discuss its appropriate diagnosis and management.

CASE PRESENTATION

We present a case of a 50-year old male presented to the consulting clinics of a University Hospital with right flank pain since the last 2 months. The Computed Tomography (CT) and biopsy on the right renal mass indicated clear cell type renal cell carcinoma with significant lymphadenopathy. Past history of cystic lung disease and pneumothorax along with positive finding of renal cell carcinoma on CT and biopsy suggested Birt-Hogg-Dub́e (BHD) syndrome. The patient underwent right radical nephrectomy and lymph node dissection. His 3 months post- surgery follow up CT scan indicated disease recurrence.

CONCLUSION

In conclusion, it is important to identify this rare syndrome at early stages. Diagnosis for the patients with a positive family history for renal cell cancer and pneumothorax should be considered. FLCN sequencing should also be taken into account in patients and their families because incidence of renal cancer in BHD patients is very high and detection at early stages can prevent its metastasis.

Oxidized regenerated cellulose induces pleural thickening in patients with pneumothorax: possible involvement of the mesothelial-mesenchymal transition

PURPOSE

The pleural covering technique, i.e., wrapping a part of or the entire surface of the lung with oxidized regenerative cellulose (ORC), reinforces visceral pleura through pleural thickening for patients with pneumothorax and cystic lung diseases. However, it remains undetermined how ORC induces pleural thickening.

METHODS

A histopathological examination was performed for lung specimens from patients who had recurrent pneumothoraces after pleural covering and re-operation (n = 5). To evaluate the influence of ORC on the pleura in vitro, we used MeT-5A cells (a human pleural mesothelial cell line).

RESULTS

Pleural thickening was confirmed in all lung specimens examined. Three months after covering, the thickened pleura showed inflammatory cell infiltration, proliferation of myofibroblasts, and expression of fibronectin and TGF-β. However, after 1 year, those findings virtually disappeared, and the thickened pleura was composed mainly of abundant collagen. When MeT-5A cells were cultured in ORC-immersed medium, their morphology changed from a cobblestone to spindle-shaped appearance. The expression of E-cadherin decreased, whereas that of N-cadherin, α-smooth muscle actin, and fibronectin increased, suggesting mesothelial-mesenchymal transition (Meso-MT).

CONCLUSIONS

Our results suggest that Meso-MT may be involved as a mechanism of pleural thickening induced by pleural covering with ORC.

Novel clinical scoring system to identify patients with pneumothorax with suspicion for Birt-Hogg-Dubé syndrome

BACKGROUND AND OBJECTIVE

Birt-Hogg-Dubé syndrome (BHDS) is a rare hereditary disease that presents with multiple lung cysts and pneumothorax (PTX). Although some reports propose that findings from chest computed tomography enable one to distinguish BHDS from primary spontaneous pneumothorax (PSP), it is still unclear whether clinical features are useful for identifying patients with suspicion of BHDS from those with PTX.

METHODS

We retrospectively reviewed the medical records of patients with PTX who underwent video-assisted thoracoscopic surgery at Nissan Tamagawa Hospital from January 2012 to December 2015.

RESULTS

We identified a total of 1141 patients with PTX, including 54 with BHDS and 517 with PSP. Among them, logistic regression analysis segregated five features that were significantly associated with BHDS: familial history of PTX, past history of bilateral PTX, age at the first episode of PTX (≥25 years old (y.o.)), body mass index (≥18.5) and gender (female). We assigned scores of 3, 3, 2, 2 and 1 to the five features, respectively, to establish a system with a calculated score from 0 to 11. The cut-off value of a calculated score ≥ 4 yielded the highest sensitivity of 93% and specificity of 86%. Receiver operating characteristic (ROC) analysis showed the area under the curve reflecting an accuracy of this diagnostic test as 0.953.

CONCLUSION

BHDS has several clinical features distinct from PSP. Our scoring system consists of only five clinical variables that are easily evaluated and efficiently separate BHDS patients from those who have PTX without relying on an imaging study. Further prospective study is needed to confirm our findings.

A Case of Recurrent Pneumothorax Associated with Birt-Hogg-Dubé Syndrome Treated with Bilateral Simultaneous Surgery and Total Pleural Covering

Birt-Hogg-Dubé syndrome is an autosomal dominant genetic disorder characterized by a triad of skin tumors, renal tumors, and multiple pulmonary cysts. Our patient was a 40-year-old man with a history of recurrent bilateral pneumothorax and a family history of pneumothorax. The patient visited our department with chest pain and was diagnosed with left pneumothorax based on a chest X-ray. Thoracic computed tomography (CT) showed multiple cysts in both lungs. We performed thoracoscopic bilateral bullectomy with curative intent. Intraoperative observation showed numerous cysts in the lung apex, interlobular region, and mediastinum. We resected the cysts that we suspected to be responsible for the symptoms and ligated the lesions, and then performed total pleural covering. After surgery, genetic testing was performed. The result enabled us to diagnose Birt-Hogg-Dubé syndrome in this patient. Although the patient has developed neither recurrent pneumothorax nor any renal tumors, to date, long-term monitoring is necessary.

Birt-Hogg-Dubé syndrome: a case report and a review of the literature

Background: Birt-Hogg-Dubé syndrome (BHDS) is a rare autosomal dominant inherited syndrome caused by mutations in the folliculin coding gene (FLCN). The clinical manifestations of the syndrome involve the skin, lungs, and kidneys. Because of the rarity of the syndrome, guidelines for diagnosis and management of the patients with BHDS are lacking.

Objective: To present a case story and a review of the literature on BHDS in order to give an update on genetics, clinical manifestations, diagnosis, treatment, prognosis and follow-up strategies.

Design: Literature review and case story.

Results: A PubMed and Embase search identified 330 papers. BHDS is characterized by small benign tumors in the skin, spontaneous pneumothoraces caused by cysts in the lungs and a seven-fold increased risk of renal cancer. A case story of a young female patient presenting with pneumothorax and a family history of recurrent pneumothoraces in many relatives illustrates how the history and the diagnostic work up resulted in a diagnosis of BHDS.

Conclusion: BHDS is a rare inherited disorder. In patients with spontaneous pneumothorax or cystic lung disease without any obvious explanation, BHDS should be considered. Concomitant skin manifestations, a family history of familiar pneumothorax, renal cancers and skin manifestations supports the suspicion of BHDS. Early diagnosis is important in order to subject patients to systematic screening for renal cancers. A radiological surveillance strategy for renal cancer is proposed.