[Multiple spontaneous pneumothoraces revealing Birt-Hogg-Dube syndrome]. / Pneumothorax itératifs et spontanés révélant un syndrome de Birt-Hogg-Dubé.

The Birt-Hogg-Dubé (BHD) syndrome is associated with cutaneous disorders including fibrofolliculomas and trichodiscomas, and also lung pneumatocysts and kidney tumours. The BHD syndrome occurs as a consequence of an autosomal dominantly inherited genodermatosis, linked to multiple germline mutations in the 14 exons of the BHD gene, mapped on 17p11.2 and encoding for folliculin (FLCN). The size and number of lung pneumatocysts are extremely variable and the cysts are surrounded by normal pulmonary tissue. In the absence of smoking lung function is usually unimpaired. The lung cysts are frequently complicated by the development of recurrent pneumothoraces. Treatment of pneumothorax in patients with the BHD syndrome is similar to the approach taken for patients with spontaneous pneumothorax. Lung cysts in the BHD syndrome are a rare cause of cystic pulmonary lesions. However, they must be systematically evaluated since kidney tumours occur in one third of patients. We report a case of classical BHD syndrome with specific cutaneous involvement, recurrent pneumothoraces complicating lung cysts, an exon 12 germline mutation on BHD gene and a familial history suggesting other related cases. This observation allows us to update this orphan disease, to consider BHD in the differential diagnosis of lung cysts and, above all, to highlight the high frequency and the prognostic significance of associated kidney tumours.

[Sweet's syndrome associated with squamous cell bronchial carcinoma. Neutrophilic dermatosis and non-small cell lung cancer]. / Syndrome de Sweet révélant un carcinome bronchique épidermoïde. Cancer bronchique et dermatose neutrophilique.

INTRODUCTION: Sweet's syndrome, one of the neutrophilic dermatoses, is idiopathic in most cases. In 10-20% of cases it is paraneoplastic, associated with a solid tumour or haematological malignancy. An association with carcinoma of the bronchus has been only rarely described. CASE REPORT: We report the case of a 56 year old man who presented with Sweet's syndrome two months before the diagnosis of a squamous cell carcinoma of the bronchus. The dermatosis responded well to corticosteroids. The progress of the tumour was favourable, with stabilisation following 3 courses of chemotherapy and local radiotherapy. DISCUSSION: This case report updates this rare association and underlines the importance of undertaking appropriate thoracic investigations in the presence of this dermatosis. A paraneoplastic secretion of interleukin-8, GM-CSF and/or G-CSF by the bronchial tumour cells facilitating the recruitment of neutrophils, particularly in the skin, may account for the pathophysiology of this condition.