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

A Possible Association of Salivary Gland Tumors and Oral Lesions with Birt-Hogg-Dube Syndrome: A Systematic Review

BACKGROUND

Birt-Hogg-Dube syndrome (BHDS) is an autosomal dominant syndrome with different skin, lung, and renal manifestations. It is diagnosed commonly in the third decade of life, and patients have an increased risk for pneumothorax and renal carcinomas.

METHODS

Articles published in PubMed, and Medline from 1977 to September 2023, were included in the systematic review. Inclusion criteria were applied to case reports, case series, and a retrospective cohort study, describing clinical, histopathological, and genetic findings in patients with BHDS with oral and/or parotid lesions.

RESULTS

Sixteen families/individuals with BHDS were identified for analysis. Patients ranged in age from 20 to 74 years, with an average of 49.4 years. Males were affected 52.2% of the time and females, 39.1%. Skin fibrofolliculomas were reported in 87% of cases, and oral lesions were documented in 47.8%. Parotid tumors were documented in 43.5% of patients, 30.4% of which were oncocytomas, 4.3% bilateral oncocytomas, and 4.3% "oncocytic carcinoma".

CONCLUSIONS

Because BHDS is uncommon, its spectrum of clinical manifestations may be underrecognized, especially as the disease is mostly reported at advanced stage. And some of the patients with BHDS may have oncocytic parotid tumors and oral lesions. In this regard, patients presenting these lesions and other indications of BHDS should be considered for renal screening.

A Rare Case of Spontaneous Pneumothorax Recurrence 30 Years After Surgery in a Patient with Birt-Hogg-Dube Syndrome: Case Presentation and Short Review of the Literature

Background

Birt-Hogg-Dube syndrome (BHDS), also known as Hornstein-Knickenberg syndrome is a rare, autosomal dominant genetic disorder characterized by a triad of clinical manifestations: skin fibrofolliculomas, renal tumors, and multiple pulmonary cysts. The exact incidence of BHDS syndrome is unknown. This hereditary syndrome is caused by mutations in the folliculin (FLCN) gene, located on chromosome 17p11.2, which encodes the folliculin protein.

Objective

This case report aims to highlight the importance of increased vigilance and long-term follow-up in BHDS patients, even decades after surgical intervention, to detect and manage potential pulmonary complications effectively. Case presentation: We present a unique case of spontaneous pneumothorax recurrence in a 63-year-old patient with a history of Birt-Hogg-Dube syndrome. The patient had undergone surgical treatment for pneumothorax 30 years ago and remained asymptomatic until presenting to our clinic with acute dyspnea and a dry cough. A recurrent pneumothorax was diagnosed and treated with a chest tube. Further chest imaging revealed extensive ground-glass opacities and cysts in both lungs. The patient was diagnosed with active pneumonia. A conservative approach was adopted due to the pneumonia diagnosis, and the patient showed a successful recovery without pneumothorax recurrence.

Conclusion

This case highlights the importance of long-term follow-up in patients with Birt-Hogg-Dube syndrome and previous pneumothorax episodes.

Birt-Hogg-Dubé syndrome: Another mTOR phenomenon

Birt-Hogg-Dubé syndrome is an uncommon autosomal dominant systemic disorder with cutaneous findings notable for fibrofolliculomas or trichodiscomas on the scalp, face, neck, and trunk. These cutaneous signs are associated with bilateral renal cell carcinoma, benign renal cysts, pulmonary cysts, and spontaneous pneumothorax. Given its autosomal dominant inheritance pattern, the successful diagnosis of Birt-Hogg-Dubé syndrome (BHDS) may elucidate a diagnosis in family members. BHDS results from a mutation in the FLCN gene encoding the folliculin protein, a transcriptional regulator of the mammalian target of rapamycin signaling pathway. Like tuberous sclerosis, BHDS's clinical features may subside with the use of oral rapamycin for mammalian target of rapamycin inhibition, a theoretical concept meriting exploration. Although its prevalence in the general population has been estimated at 2 cases per million, BHDS has been detected in a few patients from the nearby Portuguese-lineage quarter of the city of Newark, a disproportionate prevalence possibly explained by the founder effect.