Cystic lung disease

Cystic lung in sarcoidosis: Clinico-radiologic characteristic and evolution

BACKGROUND AND OBJECTIVE

Sarcoidosis can manifest with atypical findings on chest computed tomography (CT). Cysts are a rare manifestation of lung sarcoidosis. The aim of the study was to describe a series of patients with cystic sarcoidosis and their clinical-radiological characteristics and progression.

METHODS

In this retrospective, bicentric study we recruited all patients affected by sarcoidosis with lung cystic lesions at chest CT. We collected clinical characteristics, pulmonary tests and tracked number, distribution and size of the cysts at diagnosis and at the last evaluation.

RESULTS

Twelve patients (6 males, median age 53 years) were identified (prevalence: 1.9%; 95% Confidence Interval: 0.8%-2.9%). All patients presented multiple cystic lesions (median number: 14 [range: 2-216]) with a bilateral distribution in 10/12, micronodules and nodules in 11/12 and fibrotic lesions in 4/12. Seven patients had normal lung function test, three had an obstructive syndrome, one had a restrictive syndrome and one had coexistence of both. During follow-up (median: 10 years [range 1-16 years]), an increase of the number of cysts was observed in four patients. At last evaluation, 3/12 patients experienced a decline of forced vital capacity >10% and 3/12 patients a decline of diffusing capacity for carbon monoxide (DLCO) >10%. A lower DLCO at diagnosis, and the presence of nodules or fibrotic lesions on CT were associated with an increase in the number of cysts.

CONCLUSION

Cystic lung lesions are rare in patients with sarcoidosis and do not influence long term prognosis.

Dyspnea and cough in a 68-year-old female with light chain deposition disease

Light chain deposition disease (LCDD) is a rare hematologic disorder characterized by non-amyloid monoclonal immunoglobulin light chain deposition in multiple organs. Pulmonary LCDD (PLCDD) is an uncommon manifestation of LCDD usually seen in middle-aged patients presenting with radiologic cystic and nodular findings. We report the case of a 68-year-old female who presented with shortness of breath and atypical chest pain. Chest computerized tomography (CT) scan revealed numerous diffuse but basilar predominant pulmonary cysts and mild bronchiectasis without nodular disease. Given concomitant abnormal renal function and hepatic laboratory indices, she underwent biopsy of both organs confirming the presence of LCDD. Directed chemotherapy was initiated and stabilized renal and hepatic progression, but on follow-up imaging, pulmonary disease appeared worse. While therapeutic options targeting other organ involvement are available, their directed efficacy for progressive lung disease is not well known.

Quantitative Analysis of Cystic Lung Diseases by Use of Paired Inspiratory and Expiratory CT: Estimation of the Extent of Cyst-Airway Communication and Evaluation of Diagnostic Utility

PURPOSE

To establish a method for quantitatively estimating the extent of the communication between the cyst and the airway in cystic lung diseases (CLDs) and evaluate its diagnostic utility in differentiating among CLDs.

MATERIALS AND METHODS

Seventy-one patients (mean age, 49.9 years; age range, 25-79 years) with CLDs who underwent paired inspiratory and expiratory CT between July 2015 and July 2018 were enrolled in this prospective study. Participants were divided into three groups based on their diagnosis: Birt-Hogg-Dubé syndrome (BHDS) group (15 participants), lymphangioleiomyomatosis (LAM) group (43 participants), and other diseases (OT) group (13 participants). Total lung volume (TLV) and low-attenuation area volume (LAAV) were calculated at inspiration and expiration. The collapsibility of the LAAV was determined as the expiration-to-inspiration (E/I) ratio of LAAV (E/I ratio LAAV). The cyst-airway communicating index (CACI), the ratio of the LAAV change between inspiration and expiration to the TLV change between inspiration and expiration, was also determined. Receiver operating characteristic (ROC) analysis was used to evaluate the diagnostic utility for differentiating diseases.

RESULTS

The E/I ratio LAAV was significantly higher in the BHDS group (0.69; 95% confidence interval [CI]: 0.61, 0.78) than in the LAM (0.33; 95% CI: 0.28, 0.38) (P < .001) and the OT (0.51; 95% CI: 0.38, 0.64) (P = .038) groups. The CACI was significantly lower in the BHDS group (0.89; 95% CI: 0.61, 1.17) than in the LAM (1.89; 95% CI: 1.76, 2.0) (P < .001) and the OT (1.539; 95% CI: 1.21, 1.86) (P = .003) groups. There was no significant difference in the area under the ROC curve of the CACI (0.881; 95% CI: 0.7749, 0.987) and the E/I ratio LAAV (0.877; 95% CI: 0.791, 0.963) for differentiating BHDS from other diseases.

CONCLUSION

Quantitative analysis using paired inspiratory and expiratory CT for estimating the extent of cyst-airway communication in CLDs is useful when distinguishing BHDS from other diseases.Supplemental material is available for this article.© RSNA, 2020See also the commentary by Chung in this issue.

Pathology of Birt-Hogg-Dubé syndrome: A special reference of pulmonary manifestations in a Japanese population with a comprehensive analysis and review

Birt-Hogg-Dubé (BHD) syndrome is a rare genetic disorder characterized by cutaneous fibrofolliculomas, pulmonary cysts and renal cell carcinomas. Affected individuals inherit germline mutations in the folliculin gene (FLCN). Approximately 150 pathogenic FLCN variants have been identified worldwide. Many Japanese probands of BHD syndrome were first identified by pulmonologists and/or radiologists during treatment of pneumothoraces. Lung specimens obtained through video-assisted thoracoscopic surgery (VATS) have characteristic features unique to BHD syndrome; however, pathologists often miss key findings and diagnose patients with "bullae/blebs". The pleural and subpleural cysts of BHD syndrome-associated lung diseases are often modified by tissue remodeling and can be difficult to distinguish from emphysematous bullae/blebs. Intraparenchymal unruptured cysts tend to retain distinctive features that are different from other cystic lung diseases. Here, we review the clinicopathological findings of BHD syndrome in a Japanese population based on data from 200 probands diagnosed by genetic testing and a total of 520 symptomatic family members identified through BHD-NET Japan (http://www.bhd-net.jp/). Detailed morphology of pulmonary cysts obtained from VATS and autopsied lung specimens are described, and pathological clues for differentiating miscellaneous cystic lung disorders are discussed.

Cowden Syndrome: A Cause of Pulmonary Cysts

OBJECTIVE

To describe the pulmonary imaging findings in patients with Cowden syndrome (CS).

MATERIALS AND METHODS

A retrospective review identified all patients with CS who underwent dedicated computed tomography examinations of the chest at our institution between January 2000 and October 2017. Patient demographics and imaging characteristics were identified through a review of the electronic medical record and relevant imaging.

RESULTS

Fifteen patients (6 males/9 females; mean age 53 y) with a clinical diagnosis of CS were identified. Genetic confirmation of the PTEN mutation was available in 8/15 (50%) patients. Pulmonary cysts were present in 12/15 (80%) patients and in 8/8 (100%) patients with documented PTEN mutations. The cysts ranged in size from 4 to 63 mm and were <10 in 10/12 (83%). Cysts were distributed randomly in 10/12 (83%) cases. Solid pulmonary nodules were present in 13/15 (87%) patients and were distributed randomly in all cases.

CONCLUSIONS

Pulmonary cysts and solid nodules are common in patients with CS. Cysts tend to be distributed randomly, few in number, and may have traversing vessels. These findings should not be interpreted as evidence of another underlying disorder in the setting of CS.

Primary Sjögren's syndrome with diffuse cystic lung changes developed systemic lupus erythematosus: a case report and literature review

Sjögren's syndrome (SS) is a chronic inflammatory autoimmune disease that can occur as a unique existence (primary Sjögren's syndrome) or merge with other systemic diseases like systemic lupus erythematosus (SLE), rheumatoid arthritis or systemic sclerosis (secondary Sjögren's syndrome). Data on the two diseases occurrence order are inadequate. Primary Sjögren's syndrome (pSS) may relatively uncommonly lead to diffuse cystic lung changes. We represent a female who was diagnosed pSS with diffuse cystic lung alterations developed SLE two years later. SS was diagnosed on account of the existence of dryness of eye and mouth, Schirmer's test, biopsy of the minor salivary glands of her lip, positive anti-SSA and anti-SSB antibody in the serum. Chest computed tomography image showed bilateral diffuse cystic changes with a wide variation in cyst size and distribution. SLE was finally diagnosed based on bilateral lower limb skin rash, gonarthritis and omarthritis, low level of complement, antinuclear antibody 1:640 and positive antibodies to double-stranded DNA. Improvement was achieved with therapy of corticosteroids, hydroxychloroquine and antibiotics. This report provides us clinical, diagnosis and treatment perception of SS-onset SLE as patient presenting diffuse cystic lung changes.

Diagnosis and treatment of cystic lung disease

Cystic lung disease (CLD) is a group of lung disorders characterized by the presence of multiple cysts, defined as air-filled lucencies or low-attenuating areas, bordered by a thin wall (usually < 2 mm). The recognition of CLDs has increased with the widespread use of computed tomography. This article addresses the mechanisms of cyst formation and the diagnostic approaches to CLDs. A number of assessment methods that can be used to confirm CLDs are discussed, including high-resolution computed tomography, pathologic approaches, and genetic/ serologic markers, together with treatment modalities, including new therapeutic drugs currently being evaluated. The CLDs covered by this review are lymphangioleiomyomatosis, pulmonary Langerhans cell histiocytosis, Birt-Hogg-Dube syndrome, lymphocytic interstitial pneumonia/follicular bronchiolitis, and amyloidosis.

Exercise-induced haemoptysis as a rare presentation of a rare lung disease

Amyloid primarily affecting the lungs is a seldom seen clinical entity. This case discusses the work-up of a patient presenting with exercise-induced haemoptysis and diffuse cystic lung disease on radiographic imaging. The common clinical and radiographic findings of diffuse cystic lung diseases as well as a brief overview of pulmonary amyloid are presented.

Diagnosis and management of langerhans cell histiocytosis

Langerhans cell histiocytosis is a rare group of disorders without a well-understood etiology. Known formerly as histiocytosis X, the disease has a wide spectrum of clinical presentations, including eosinophilic granuloma (solitary bone lesion), diabetes insipidus, and exophthalmos. It is also known by several eponyms, including Hand-Schüller-Christian disease when it manifests as a triad of cranial bone lesions and Letterer-Siwe disease when it is found in infantile patients with severely disseminated disease. Children aged 5 to 15 years are most commonly affected. Many of these patients initially present to orthopaedic surgeons, and misdiagnosis is frequent. To accurately diagnosis and treat these patients, the orthopaedic surgeon must be familiar with the clinical manifestations and pathophysiology of the disease as well as the treatment guidelines and outcomes for Langerhans cell histiocytosis.

Spontaneous pneumothorax as indicator for Birt-Hogg-Dubé syndrome in paediatric patients

Background

Birt-Hogg-Dubé syndrome (BHD) is a rare autosomal dominantly inherited disorder caused by germline mutations in the folliculin (FLCN) gene. Clinical manifestations of BHD include skin fibrofolliculomas, renal cell cancer, lung cysts and (recurrent) spontaneous pneumothorax (SP). All clinical manifestations usually present in adults > 20 years of age.

Case presentations

Two non-related patients with (recurrent) pneumothorax starting at age 14 accompanied by multiple basal lung cysts on thoracic CT underwent FLCN germline mutation analysis. A pathogenic FLCN mutation was found in both patients confirming suspected BHD. The family history was negative for spontaneous pneumothorax in both families.

Conclusion

Although childhood occurrence of SP in BHD is rare, these two cases illustrate that BHD should be considered as cause of SP in children.