SESSION TYPE: Pleural Global Case Report Posters
PRESENTED ON: Tuesday, October 23, 2012 at 01:30 PM - 02:30 PM
INTRODUCTION: A spontaneous pneumothorax is defined as air entering the pleural space without antecedent trauma to the thorax. This may be sub-classified into primary spontaneous pneumothorax (PSP) - occurring in the absence of an underlying lung disease. A subtype of PSP is classified as familial. Here, we present the first Filipino family documented to have Birt-Hogg-Dube (BHD) Syndrome - an autosomal dominant condition manifesting as familial primary spontaneous pneumothorax.
CASE PRESENTATION: A 32 year old Filipino male came in due left sided chest pain and difficulty of breathing. Chest x-ray revealed a 50-60% left sided pneumothorax, which resolved after inserting a chest tube. Chemical pleurodesis was done using tetracycline prior to the removal of the chest tube. This was the patient’s second admission for PSP. Three years prior, the patient’s 50 year old paternal aunt, complained of left sided chest discomfort. A 40% left sided pneumothorax was seen on chest radiograph. She underwent video assisted thoracoscopy with stapling of bullae and mechanical pleurodesis. She was discharged without complications. The following year, she underwent nephrectomy for a malignant right renal mass noted on CT scan and biopsy. Six years earlier, the patient’s 27 year old sister was admitted for gradually worsening right sided chest discomfort of one month duration. Chest x-ray revealed an approximately 10% pneumothorax on the right. She was given oxygen therapy. Repeat chest x-ray, done after 2 weeks, showed resolution of pneumothorax. Review of family history revealed five more relatives who had spontaneous pneumothorax and another relative with renal cell carcinoma.
DISCUSSION: A strong family history of PSP with an autosomal dominant transmission provided a high degree of suspicion of an underlying familial condition. Among the causes of familial primary spontaneous pneumothorax, Birt-Hogg-Dube Syndrome (BHD) fit the spectrum of disease seen in the patient’s family. BHD syndrome is a rare inherited genodermatosis caused by germline mutations in the folliculin (FLCN) gene mapped to chromosome 17p12q11. It is characterized clinically by pulmonary cysts, spontaneous pneumothorax, renal cancer and skin fibrofolliculomas. Genetic testing done on the patients and on 44 consenting family members revealed a previously reported frameshift mutation due to a deletion of one cytosine within the coding region of exon 11, c.1252delC (p.L418TfsX50) in the folliculin gene product of all patients and 14 family members. Upon confirmation of the diagnosis, genetic counselling was provided for the patients as well as for the other affected family members, emphasizing the need for constant medical surveillance to detect PSP and renal carcinoma at an early age. The affected individuals were advised to undergo renal ultrasound or magnetic resonance imaging for screening of renal mass, since they have seven times the risk of having renal cancer - the most threatening complication of this syndrome.
CONCLUSIONS: Frequent incidence of PSP in a family should warrant a high degree of suspicion of familial causes - including BHD syndrome. Individuals suspected to have BHD syndrome and their 1st degree families should be further investigated and should ideally undergo molecular analysis for definitive diagnosis.
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3) Menko F, Van Steensel MA, Giraud S, et. al. Birt-Hogg-Dube syndrome: diagnosis and management. Lancet Oncol 2009; 10(12):1199-1206
DISCLOSURE: The following authors have nothing to disclose: Rodolfo Dizon, Nino Jessielito Doydora, Ricardo Salonga, Jose Edzel Tamayo, Catherine Lynn Silao, Megan Devine, Christine Kim Garcia, J. Jose Turla, Gener Idor
No Product/Research Disclosure InformationUniversity of Perpetual Help DALTA Medical Center Section of Pulmonary Medicine, Las Pinas City, Philippines