A case of tracheobronchial amyloidosis with emphasis on differential diagnosis.

Tracheobronchial amyloidosis is a manifestation of amyloidosis of the respiratory tract characterized by focal or diffuse deposition of amyloid in the submucosa of the trachea and proximal bronchi. Tracheobronchial amyloidosis is not associated with systemic amyloidosis or pulmonary parenchymal involvement. It affects predominantly men aged over fifty. Depending on the part of the tracheobronchial tree that is affected, stenosis of the airways causes a variety of unspecific symptoms. Diagnosis is reached by means of typical presentation in CT scan followed by bronchoscopy and histopathological confirmation. Tracheobronchial amyloidosis should be borne in mind in the differential diagnosis of patients with chronic cough and/or dyspnea or recurrent respiratory infections.

[Risk factors for pulmonary atelectasis in adults with tracheobronchial tuberculosis].

Objective: To investigate the risk factors for pulmonary atelectasis in adults with tracheobronchial tuberculosis(TBTB). Methods: Clinical data of adult patients (≥18 years old) with TBTB from February 2018 to December 2021 in Public Health Clinical Center of Chengdu were retrospectively analyzed. A total of 258 patients were included, with a male to female ratio of 1∶1.43. The median age was 31(24, 48) years. Clinical data including clinical characteristics, previous misdiagnoses/missed diagnoses before admission, pulmonary atelectasis, the time from symptom onset to atelectasis and bronchoscopy, bronchoscopy and interventional treatment were collected according to the inclusion and exclusion criteria. Patients were divided into two groups according to whether they had pulmonary atelectasis. Differences between the two groups were compared. Binary logistic regression was used to analyze the risk factors for pulmonary atelectasis. Results: The prevalence of pulmonary atelectasis was 14.7%, which was most common in the left upper lobe (26.3%). The median time from symptom onset to atelectasis was 130.50(29.75,358.50)d, and the median time from atelectasis to bronchoscopy was 5(3,7)d. The median age, the proportion of misdiagnosis of TBTB before admission, and the time from symptom onset to bronchoscopy in the atelectasis group were higher than those without atelectasis, and the proportion of receiving bronchoscopy examination and interventional therapy previously, and the proportion of pulmonary cavities were lower than those without atelectasis (all P<0.05). The proportions of cicatrices stricture type and lumen occlusion type in the atelectasis group were higher than those without atelectasis, while the proportions of inflammatory infiltration type and ulceration necrosis type were lower than those without atelectasis (all P<0.05). Older age (OR=1.036, 95%CI: 1.012-1.061), previous misdiagnosis(OR=2.759, 95%CI: 1.100-6.922), longer time from symptom onset to bronchoscopy examination (OR=1.002, 95%CI: 1.000-1.005) and cicatrices stricture type (OR=2.989, 95%CI: 1.279-6.985) were independent risk factors for pulmonary atelectasis in adults with TBTB (all P<0.05). Of the patients with atelectasis who underwent bronchoscopy interventional therapy, 86.7% had lung reexpansion or partial reexpansion. Conclusions: The prevalence of pulmonary atelectasis is 14.7% in adult patients with TBTB. The most common site of atelectasis is left upper lobe. The TBTB type of lumen occlusion is complicated by pulmonary atelectasis in 100% of cases. Being older, misdiagnosed as other diseases, longer time from onset of symptoms to bronchoscopy examination, and being the cicatrices stricture type are factors for developing pulmonary atelectasis. Early diagnosis and treatment are needed to reduce the incidence of pulmonary atelectasis and increase the rate of pulmonary reexpansion.

Left Main Bronchus Stenosis Lesion, Neutrophil Count, and Platelet Count Are Predictors of Post-Tuberculosis Bronchomalacia.

BACKGROUND Post-tuberculosis bronchomalacia (PTBM) is one of the main conditions occurring in patients after tracheobronchial tuberculosis (TBTB), and is also associated with the recurrence of symptoms. The present study aimed to investigate the predictors of PTBM in patients who had been undergoing appropriate TB treatment. MATERIAL AND METHODS Clinical data of 104 patients with symptomatic airway stenosis after TBTB between January 01, 2019 and June 31, 2020 were recorded and analyzed. The association between baseline clinical characteristics, laboratory results, and PTBM was calculated with logistical regression. The time from onset of bronchoscopic intervention was examined by Kaplan-Meier estimates; differences between the 2 groups were tested by the log-rank test. RESULTS Fifty-seven patients (54.81%) had PTBM. In the multivariate logistical analysis, the left main bronchus stenosis lesion (odds ratio [OR]=3.763), neutrophil (NEUT) count (OR=1.527), and platelet (PLT) (OR=1.010) count were predictors of PTBM. During follow-up, patients with BM had a significantly longer duration from onset of bronchoscopic intervention than patients without BM (hazard ratio=2.412, P<0.0001). Further, all patients needing long-term bronchoscopic intervention therapy were subsequently identified as having PTBM. Additionally, blood PLT counts were significantly decreased to normal levels in the non-BM group (P<0.05), but not in the BM group (P>0.05). CONCLUSIONS PTBM is most likely to occur in the left main bronchus. The inflammatory and immune responses associated with NEUT and PLT may represent therapeutic targets of PTBM. Our study is the first to report that decreased blood PLT count has the potential to monitor the treatment response.

Long-term prognostic factors of clinical success after interventional bronchoscopy in patients with scarring central airway stenosis.

BACKGROUND: Scarring central airway stenosis (SCAS) is a potentially life-threatening condition with debilitating symptoms. Interventional bronchoscopy is increasingly used to relieve symptoms in patients with SCAS, but recurrent stenosis is frequently observed. Little data exist on the long-term prognosis of interventional bronchoscopy for SCAS. We aimed to assess the prognostic factors of bronchoscopic interventions in patients with SCAS to optimize treatment. METHODS: This was a retrospective study that enrolled 119 consecutive patients with SCAS from January 2010 to April 2019 at our institution. Long-term clinical success was defined as airway stenosis < 50%, no limitation of physical activity, and a stable condition for > 12 months after the last interventional procedure. We compared patients' demographics, airway stenosis characteristics, and interventional procedures between the successful and unsuccessful groups, and identified significant predictors of long-term outcome with univariate and multivariate logistic regression. RESULTS: A total of 119 patients with 577 therapeutic bronchoscopies were included. Seventy-five (63%) patients were considered to have long-term clinical success. Older age, male gender, smoking, elevated C-reactive protein level, subglottic stenosis, stent or T-tube implantation, previous interventional treatment, and multiple procedures per year were potentially associated with unsuccessful long-term outcomes in the univariate analysis. Current smoker status (odds ratio [OR] 5.70, 95% confidence interval [CI] 1.35-24.17, P = 0.018), subglottic stenosis (OR 4.35, 95% CI 1.31-14.46, P = 0.017), and stent implantation (OR 4.96, 95% CI 1.33-18.48, P = 0.017) were associated with decreased odds of long-term success in the multivariate logistic regression analysis. Of note, there was no significant difference in odds of success between former smokers and nonsmokers. CONCLUSIONS: Current smoker status, subglottic stenosis, and stent implantation are independent factors associated with reduced long-term efficacy of interventional bronchoscopy for SCAS. Smoking cessation should be encouraged to improve the outcome of therapeutic bronchoscopy.

Development of polymer-based nanoparticles for zileuton delivery to the lung: PMeOx and PMeOzi surface chemistry reduces interactions with mucins.

In this paper, two amphiphilic graft copolymers were synthesized by grafting polylactic acid (PLA) as hydrophobic chain and poly(2-methyl-2-oxazoline) (PMeOx) or poly(2-methyl-2-oxazine) (PMeOzi) as hydrophilic chain, respectively, to a backbone of α,ß-poly(N-2-hydroxyethyl)-D,L-aspartamide (PHEA). These original graft copolymers were used to prepare nanoparticles delivering Zileuton in inhalation therapy. Among various tested methods, direct nanoprecipitation proved to be the best technique to prepare nanoparticles with the smallest dimensions, the narrowest dimensional distribution and a spherical shape. To overcome the size limitations for administration by inhalation, the nano-into-micro strategy was applied, encapsulating the nanoparticles in water-soluble mannitol-based microparticles by spray-drying. This process has allowed to produce spherical microparticles with the proper size for optimal lung deposition, and, once in contact with fluids mimicking the lung district, able to dissolve and release non-aggregated nanoparticles, potentially able to spread through the mucus, releasing about 70% of the drug payload in 24 h.

Endobronchial hamartoma in a young COVID-19 symptomatic woman. Radical endoscopic treatment with a disposable bronchoscope. Case Report.

Pulmonary hamartomas represent the most frequent family of benign lung tumors that typically involve the lung parenchyma and only rarely grow as endobronchial tumors. The elective treatment of endobronchial hamartoma is the bronchoscopic resection, and in those cases in which tumor extension and localization makes it not possible, surgical treatment must be evaluated. Patients with symptomatic COVID-19, hospitalized, frequently undergo a chest CT scan and in some cases, occasional findings may emerge, requiring diagnostic investigations such as bronchoscopy and interventional pulmonology procedures. Therefore, in such a delicate pathological condition, such as COVID-19, the need to perform bronchoscopy and interventional pulmonology procedures, minimizing the risk of viral transmission and ensuring necessary assistance, represents a great challenge for pulmonologists. In this article authors describe, for the first time in literature, a rare case of endobronchial hamartoma, radically resected using a single use bronchoscope, in a young female patient hospitalized for symptomatic COVID-19.

Bronchiolitis and Bronchiolar Disorders.

Bronchioles are noncartilaginous small airways with internal diameter of 2 mm or less, located from approximately the eighth generation of purely air conducting airways (membranous bronchioles) down to the terminal bronchioles (the smallest airways without alveoli) and respiratory bronchioles (which communicate directly with alveolar ducts and are in the range of 0.5 mm or less in diameter). Bronchiolar injury, inflammation, and fibrosis may occur in myriad disorders including connective tissue diseases, inflammatory bowel diseases, lung transplant allograft rejection, graft versus host disease in allogeneic stem cell recipients, neuroendocrine cell hyperplasia, infections, drug toxicity (e.g., penicillamine, busulfan), inhalation injury (e.g., cigarette smoke, nylon flock, mineral dusts, hard metals, Sauropus androgynous); idiopathic, common variable immunodeficiency disorder, and a host of other disorders or insults. The spectrum of bronchiolar disorders is wide, ranging from asymptomatic to fatal obliterative bronchiolitis. In this review, we discuss the salient clinical, radiographic, and histological features of these diverse bronchiolar disorders, and discuss a management approach.

Histology of Pulmonary and Bronchiolar Disorders in Connective Tissue Diseases.

Connective tissue diseases (CTDs) are a heterogeneous group of disorders, acquired or hereditary, involving an autoimmune-mediated inflammation of connective tissues in the whole body. Lung involvement is common with CTDs, and associated with significant morbidity and mortality. Each compartment of the lung may be affected, often simultaneously, depending on the type of CTD. In addition, the lung may show pathological changes related to treatment, such as infection, drug reaction, and neoplasia. A multidisciplinary approach to diagnose these patients is essential and incorporates radiological and clinical as well as pathological data. In this review we describe the patterns of lung disease associated with common CTDs, lung disease in pediatric CTD patients, and newly recognized conditions.

A case of spheroid-type localized lactoferrin amyloidosis in the bronchus.

We report a case of localized bronchial lactoferrin amyloidosis. A 47-year-old man presented with a complaint of persistent dry cough for two months. Chest computed-tomography revealed a calcification shadow of the right main bronchus; hence, a biopsy was performed, showing layered spheroid-type eosinophilic deposits in the bronchial wall. These deposits were positive for Congo red staining, exhibiting apple-green birefringence under polarized light. In addition, an electron microscopic examination demonstrated that this layered structure was formed by very thin cord-like amyloid deposits. By proteomics analysis using liquid chromatography-tandem mass spectrometry and immunohistochemistry, we confirmed that the deposited amyloid was composed of lactoferrin. While lactoferrin is known to be a precursor protein of localized corneal and seminal vesicle amyloidosis, localized lactoferrin amyloidosis of the bronchus has not been reported in the English literature. Our pathological findings suggested that localized lactoferrin amyloidosis may be caused by long-term tissue damage, and the characteristic spheroid-type appearance is thought to be associated with unique, thin cord-like amyloid deposits.

The computed tomographic "tree-in-bud" pattern: Characterization and comparison with radiographic and clinical findings in 36 cats.

In humans, a CT "tree-in-bud" pattern has been described as a characteristic of centrilobular bronchiolar dilation, with bronchiolar plugging by mucus, pus, or fluid. Aims of this retrospective, descriptive, multi-center study were to characterize the CT appearance of a "tree-in-bud" pattern in a group of cats, and compare this pattern with radiographic and clinical findings. Databases from four hospitals were searched during the period of January 2012 to September 2015 and cats with thoracic radiographs, thoracic CT scans and CT reports describing findings consistent with a "tree-in-bud" pattern were included. Images were reviewed by two veterinary radiologists and characteristics were recorded based on consensus. Clinical findings were recorded by one observer from each center. Thirty-six cats met inclusion criteria. Six cats were asymptomatic, 12 were diagnosed with bronchial disease and 23 were suspected to have bronchial disease. Right cranial and right caudal lung lobes were most commonly affected on both imaging modalities. Localization of the "tree-in-bud" pattern was most often peripheral. On radiographs, the CT "tree-in-bud" pattern often appeared as soft-tissue opacity nodules; their number and affected pulmonary segments were often underestimated compared with CT. In conclusion, the "tree-in-bud" pattern should be considered as a differential diagnosis for radiographic soft tissue opaque nodules in feline lungs. Based on lesion localization and presence or suspicion of a concomitant bronchial disease for cats in this sample, authors propose that the CT "tree-in-bud" pattern described in humans is also a characteristic of bronchial or bronchiolar plugging and bronchial disease in cats.

Middle lobe syndrome: An exceptional presentation of concomitant lepidic adenocarcinoma and bronchial anthracofibrosis.

Lepidic adenocarcinoma previously known as bronchioloalveolar carcinoma (BAC) is a non-small cell lung cancer with an indolent presentation. Bronchial anthracofibrosis (BAF) is caused by long-standing exposure to biomass fuel smoke often in poorly ventilated kitchen. Middle lobe syndrome (MLS) due to BAF is not uncommon however, lepidic adenocarcinoma then known as BAC, presenting as MLS has been documented only once before in the Polish literature. A 68-year-old never-smoker female with biomass fuel smoke exposure presented with cough and breathlessness. Imaging revealed MLS. Fiberoptic bronchoscopy visualised bluish-black hyperpigmentation with narrowing and distortion of right middle lobe bronchus suggestive of BAF. Transbronchial biopsy confirmed presence of lepidic adenocarcinoma. To our knowledge, this is the first detailed description of lepidic adenocarcinoma and BAF presenting as MLS.

Clinical features and prognostic significance of splenic involvement in sarcoidosis.

Sarcoidosis is a systemic disease characterized by noncasefied granulomas in various organs. Incidence of splenic disease is variable and is reported to occur in 6.7 to 77 percent of the patients. Firm data establishing the clinical features and the association of splenic involvement with prognosis in sarcoidosis is scant. The aim of our study was to investigate the clinical features and the consequence of splenic involvement on the prognostic outcome of sarcoidosis patients. We evaluated the clinical and laboratory findings in 82 sarcoidosis patients. Forty-two patients with splenic involvement were compared to 48 sarcoidosis patients without splenic disease in regard to laboratory findings, endobronchial disease, extrapulmonary organ involvement, and prognosis. Lung biopsy sample was considered positive if it demonstrated noncaseating granulomas with negative fungal and mycobacterial cultures. Splenic sarcoidosis was identified by ultrasound or computed tomography and was designated as limited, diffuse or without splenic involvement. Extrapulmonary organ sarcoidosis was classified as extensive and limited. Endobronchial disease was categorized as limited or diffuse involvement. The most commonly comprised organ was lung in 95% of the cases followed by lymph nodes, skin, eye, spleen and liver in the order of frequency. Splenic disease was diffuse in 22 patients. Of these patients, 14 had extensive extrapulmonary organ involvement while 16 had diffuse endobronchial disease. There was no significant difference between the three groups for FEV1, FVC, TLC, DLCO/VA, serum and 24h urinary calcium levels. Serum ACE was higher in patients with diffuse splenic involvement (p<0.001). Incidence of persistent chronic disease was significantly higher (p<0.001) in patients with diffuse splenic sarcoidosis. Extensive extrapulmonary organ involvement and diffuse endobronchial disease were more common (p<0.001) in this group. Extensive extrapulmonary organ involvement and diffuse endobronchial disease were more frequent in patients with diffuse splenic sarcoidosis. Patients with diffuse splenic granulomas had a worse prognosis than the patients without splenic involvement or patients with limited splenic disease. Diffuse splenic involvement emerges to be a significant risk factor for persistent chronic sarcoidosis. Extensive granuloma burden in an organ may be the decisive clinical marker for the prognostic outcome of sarcoidosis patients.

Imaging of Large Airways Disorders.

OBJECTIVE: Recent technical advances, including the routine use of CT thin sections and techniques such as 2D minimum-intensity-projection and 3D volume images, have increased our ability to detect large airways diseases. Furthermore, dedicated CT protocols allow the evaluation of dynamic airway dysfunction. CONCLUSION: With diseases of the large airways more commonly seen in daily practice, it is important that radiologists be familiar with the appearances, differential diagnosis, and clinical implications of these entities.

Multilevel airway stenosis in patients with granulomatosis with polyangiitis (Wegener's).

OBJECTIVES: To describe the presentation and clinical course of subglottic stenosis (SGS), in particular the development of concurrent airway lesions, in patients with Granulomatosis with Polyangiitis (Wegener's) (GPA). MATERIALS AND METHODS: Retrospective review of clinical data from all patients presenting to our institution from 2000 to 2012 with SGS and GPA. RESULTS: Thirty-five patients were identified. The average age at diagnosis was 33 years old. Eleven patients (31%) presented with SGS as part their initial manifestation of GPA. The remaining patients developed SGS later, at a median of 2.5 years from diagnosis (range 6 months to 14 years). Twelve patients (34%) were noted to have multilevel airway involvement. Seven patients (20%) had documentation of cricoarytenoid joint fixation and vocal cord immobility. This was typically progressive in nature and occurred at an average of two years following the diagnosis of SGS. Six patients (17%) had mid/distal tracheal stenosis and four (11%) had bronchial stenosis. The majority of patients (86%) had evidence of concurrent sinonasal involvement, ten patients (29%) had evidence of otologic involvement and eight (23%) had ocular involvement. CONCLUSIONS: Cricoarytenoid joint fixation and distal stenosis occur not infrequently in patients with GPA and SGS, resulting in progressive multilevel airway stenosis in about one third of patients. It is critical to identify multilevel stenosis when managing the airways of these patients.

Computed tomography virtual bronchoscopy: normal variants, pitfalls, and spectrum of common and rare pathology.

A broad spectrum of pathologies that involve the laryngotracheobronchial airway and imaging plays a crucial role in evaluating these abnormalities. Computed tomography with virtual bronchoscopy has been found to be very helpful in defining the location, extent, and nature of these lesions, and is increasingly being used even in patients with contraindications for fiberoptic bronchoscopy and laryngoscopy. Ionizing radiation, associated with virtual bronchoscopy, can be minimized by using low-dose multidetector computed tomography and hybrid iterative reconstruction techniques. Furthermore, retrospectively generated virtual bronchoscopy from a routinely acquired computed tomography data set eliminates additional cost and radiation. In the future, virtual bronchoscopy assisted with advanced navigational techniques will broaden the diagnostic and therapeutic landscape. This article presents the characteristic features of common and rare laryngotracheobronchial pathologies seen with virtual bronchoscopy.

[Acquired Bronchial Atresia due to Endobronchial Tuberculosis].

A 37-year-old woman was re-admitted to our hospital because the recurrence of endobronchial tuberclosis was suspected. Mycobacterium tuberculosis was not detected by culture of sputum and gastric fluid, and computed tomography revealed a left superior segmental bronchus obstruction and pneumonia. Her pneumonia improved by administration of antibiotics, but the strong cough persisted. Bronchoscopic examination revealed that the left superior segmental bronchus was blind. Mycobacterium tuberculosis was not detected from a biopsy of the blind bronchus wall. We diagnosed that her obstructive pneumonia was due to acquired atresia after endobronchial tuberculosis. Because a persistent cough even after the treatment of pneumonia indicated the possibility of recurrent obstructive pneumonia, surgical resection was performed. The postoperative course was uneventful and the patient was discharged on the 8th postoperative day. The atresia of the superior segmental bronchus was histologically considered to be acquired atresia due to the inflammation from tuberculosis.

[Diagnosis of primary tracheobronchial amyloidosis by multiplanar reconstruction of the computed tomography combined with bronchoscope].

OBJECTIVE: To summarize the specific CT characteristics and the endoscopic findings of primary tracheobronchial amyloidosis (PTBA) for improvement of the diagnostic accuracy.
 METHODS: The imaging features of 6 patients with PTBA were analyzed by multiplanar reconstructed CT and the fiberoptic bronchoscope, and the pathology were summarized retrospectively.
 RESULTS: All PTBA patients received bronchoscopic examination and the definite diagnosis were confirmed by positive staining with Congo red. PTBA presented diffuse thickening of major airway and lumen stenosis in various degrees with scattered hemorrhage of the mucous membrane under CT and bronchoscope, which was more obvious in low part of trachea, main bronchus and lobar bronchus. The mucosa of trachea and bilateral main bronchi were irregular and bumpy with jutting nodes in 5 patients, which was called "wavy path" pattern. Widely nodular or stripy calcifications of airway were found in 4 patients, which was considered as specific imaging features in PTBA and was involved bilateral main bronchi largely. There were obstructive atelectasis in 2 patients, and calcifications of hilus of lung with longitudinal diaphragm lymph nodes in 3 patients, but they were not specific. Ignoring the extensive circumferential thickening of large airway, "wavy path sign" and rail-like calcification was mainly responsible for misdiagnosis of PTBA as endobronchial tuberculosis or other diseases.
 CONCLUSION: Attentions to the specific imaging features on multiplanar CT and the endoscopic findings are the fundamentals to avoid the misdiagnosis of PTBA.