New Japanese case study and clinical features of Japanese studies

Tanegashima et al., 2016 report the case of a 54-year-old Japanese man presenting with skin-coloured papules on his face and neck. Pathological examination revealed the presence of fibrofolliculoma. The patient’s sister was previously diagnosed with BHD Syndrome with multiple pulmonary cysts and renal cell carcinomas but no skin symptoms. CT exams revealed the presence of multiple pulmonary cysts and a renal tumor diagnosed as a chromophobe renal cell carcinoma on the male patient. Genetic analysis revealed a germ line mutation of FLCN in exon 11 (c.1285dupC), the same as his sister. He was diagnosed with BHD with all three symptoms. It is possible that the frequency of each clinical BHD symptom differs with race and gender. The authors analyzed the symptoms of 68 Japanese BHD cases from the available publications from 1990 to 2015. Pulmonary cysts and renal cell carcinomas were found in 82.4% and 29.4% of Japanese patients, and their prevalence was similar to that in Caucasians. However, significantly fewer skin lesions were found in Japanese than in Caucasians (43.1% vs 90.0%). In addition, Japanese men had a significantly higher prevalence of skin lesions than women (66.7% vs 31.3%).

First case of BHD Syndrome reported in Poland

Radzikowska et al. (2016) report the case of a 54-year-old woman presenting with recurrent pneumothoraces and with recurrent pneumothoraces in her family history. A CT scan showed multiple cysts in the lower parts of both lungs. In addition,  liver and renal cysts were revealed in the abdomen. Genetic analysis revealed a mutation in the FLCN gene (c.469_471delTTC(p.Phe157del)) confirming the diagnosis of BHD.

According to the authors, this is the first case of BHD reported in Poland.

This case study is freely available to download in the BHD Article Library: Clinical Research

New website coming + closing “Living with BHDS” Forum

Hi everyone! We are close to launching our new BHDsyndrome website, we are very excited about it! We will close the Forum “Living with BHD Syndrome” and we suggest that people join the Birt Hogg Dube Syndrome group on Facebook that serves the same purpose: asking questions and sharing experiences. We will keep the Forum info archived and available on the new website. As always suggestions and feedback are very welcome

New study: FLCN mutations in Danish BHD patients

In their new study, Rossing et al. (2016) have identified 13 different variants and 3 common polymorphism in the FLCN gene in 143 Danish patients with suspected BHD syndrome. 6 of these variants are novel, 9 are classified as pathogenic and 1 as likely pathogenic. Single nucleotide polymorphism (SNP) analysis revealed that a specific variant (c.1062+2T>G) is a founder mutation shared among all the Danish carriers. These findings contribute to extend our knowledge of the FLCN mutation spectrum.

Co-existence of BHD and other inherited conditions: new case report

Whitworth et al. (2016) present the case of a 58-year-old woman with a variety of disease manifestations including an oncocytoma in the submandibular gland, presence of multiple hemangiomas/cavernous malformations in the cerebrum and cerebellum, pulmonary bullae, a spontaneous pneumothorax episode, a goitre and facial rash.

From the medical history and clinical manifestations, two rare diseases were considered: BHD and hereditary cavernous cerebral malformations (CCM). Genetic testing of the relevant genes revealed mutations in the FLCN and CCM2 genes. Follow-up scan of the kidneys showed multiple small cysts and pulmonary bullae.

The authors suggest that when potentially novel clinical features are manifested, co-existing conditions should be considered and extensive genetic testing should be performed. The increased use of next generation sequencing in diagnosis is likely to reveal more cases such as this.

This case study is freely available to download in the BHD Article Library: Clinical Research.

Three new BHD case studies

Dow et al. (2016) present the case of a BHD patient with a renal angiomyolipoma, a neoplastic lesion usually associated with TSC. There is both clinical and molecular overlap between BHD and TSC. In addition, both FLCN and TS proteins appear to play important roles in the mTOR pathway. This case further illustrates the overlap between BHD and TS and how genetic testing is important to establish a firm diagnosis.

Burkett et al. (2016) present the case of a 46-year-old man with spontaneous pneumothorax secondary to bullous emphysema caused by a novel mutation (c.1219delA) in the folliculin (FLCN) gene.

Dardour et al. (2016) present the case of 57-year-old man with Smith-Magenis syndrome (SMS), a contiguous-gene disorder most commonly caused by a deletion of chromosome 17p11.2. The patient presented bilateral renal tumors most likely related to haploinsufficiency of FLCN gene, located in the deleted region. Mutations of FLCN cause BHD syndrome, characterized by pulmonary cysts, skin and renal tumors. This case suggests that patients with SMS should also be checked for possible manifestations of BHD.

Two of these studies are freely available to download in the BHD Article Library: Clinical Research.

Mendeley BHD Literature Database Group

In addition to our existing Access BHD Literature Database available for download, it is now possible to freely join the Mendeley BHD Literature Database group by clicking the link below:

Mendeley BHD Literature Database Group

Mendeley is a combination of a desktop free application and a website which helps manage, share and discover research publications