Characterization of CT scans of patients with Birt-Hogg-Dubé syndrome compared with those of Chinese patients with non-BHD diffuse cyst lung diseases

Abstract

Background and objective The purpose of this study was to create a practical CT-based algorithm to differentiate Birt-Hogg-Dubé (BHD) syndrome from other diffuse cystic lung diseases (DCLD). Methods The study was a retrospective review of the CT images of 33 patients with BHD syndrome, 33 patients with LAM, and 23 patients with NBNL (non-BHD and non-LAM) among DCLD patients. On the basis of the data collected, the CT images were reviewed again to evaluate the characteristics (size, number, distribution, and morphology) of pulmonary cysts. Results Lower lung-predominant cysts were more likely to be found in patients with BHD syndrome than in patients with LAM or in the NBNL DCLD group. In the axial distribution, 18 of 33 patients in BHD group had cysts that were predominantly near the mediastinum, and all the patients in the LAM and NBNL DCLD groups had diffuse cysts. The appearance of fusiform cysts was more easily observed in patients in the BHD group. In total, 58% patients in the BHD group had less than 50 lung cysts, while all patients in the non-BHD group had more than 50 lung cysts. The biggest cyst was located in the lower lobe in 28 of 33 patients in the BHD group, while 11 of 33 patients in LAM group and 10 patients in the NBNL DCLD group had the biggest cyst in the lower lobe. Conclusion The pulmonary cysts in patients with BHD tended to be fusiform, less numerous and located predominantly in the lower lobe and near the mediastinum. These radiologic pulmonary features could assist physicians in differentiating BHD from other DCLDs.

Birt–Hogg–Dubé syndrome in Chinese patients: a literature review of 120 families

“…A study in Japan established a scoring system that has a high degree of sensitivity and specificity for distinguishing suspected BHDS from primary spontaneous pneumothorax [39]. Several radiological studies also found appropriate evaluation of chest CT images to be helpful in differentiating BHDS from other diffuse cystic lung diseases [40][41][42][43][44]. Therefore, the most common presentation pneumothorax in setting of characteristic cystic lung lesions or a family history of pneumothorax should suggest the need for FLCN gene testing to make timely diagnosis.…”

Birt-Hogg-Dubé Syndrome Encountered At Rare Lung Disease Clinic In Anhui Province, China

“…However, our study shows that skin lesions were present in nearly 70% of patients and suggests this feature may have been overlooked previously. This explanation is supported by the observation that the prevalence of skin manifestations in patients with BHDS reported from Peking Union Medical College hospital (PUMCH) increased from 11% in 2017 to 47.2% in 2019 and 54.5% in 2020 (11,17,20). Furthermore, Iwabuchi et al detected skin lesions in 26/31 (83.9%) Japanese patients with BHDS using dermoscopy and skin biopsy con rmed brofolliculoma and/or trichodiscoma histologically in 73.9%(28).…”

“…Multiple pulmonary cysts detected on chest CT are the most common manifestation and has been described in 85-99% of cases in various study cohorts (7,8,10). The number, shape, size, and distribution of pulmonary cystic lesions are helpful to distinguish BHDS from other cystic lung diseases (20,21). On chest CT, BHDS is characterized by multiple, irregular-shaped cysts of varying sizes with medial and basal predominance in distribution (20,22,23).…”

“…Chest computed tomography (CT) studies of each patient were assessed by two pulmonary physicians(XH, GZ) independently for the presence of pneumothorax, cysts and cyst localization(upper or lower dominant; central or peripheral dominant), cyst number ( 10,(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)20), cyst size (maximum diameter: < 1cm, 1-2cm, 2-5cm, >5cm), and cyst shape (round to oval, irregular). CT, ultrasound or magnetic resonance imaging of the abdomen was used for renal assessment.…”

Birt-Hogg-Dubé Syndrome in Chinese Patients:&nbsp;A Literature Review of 120 Families

“…A study in Japan established a scoring system that has a high degree of sensitivity and speci city for distinguishing suspected BHDS from primary spontaneous pneumothorax 37 . Several radiological studies also found appropriate evaluation of chest CT images to be helpful in differentiating BHDS from other diffuse cystic lung diseases [38][39][40][41][42] . Therefore, the most common presentation pneumothorax in setting of characteristic cystic lung lesions or a family history of pneumothorax should suggest the need for FLCN gene testing to make timely diagnosis.…”