Right middle lobe syndrome after upper lobectomy: Role of the bronchial angle.

BACKGROUND: Right middle lobe syndrome is part of a spectrum of relatively rare but serious conditions that may occur following right upper lobectomy. We aimed to assess whether the preoperative middle lobe bronchial angle on CT predicted patients at risk of developing middle lobe syndrome. METHOD: All patients who had a complete upper lobectomy over 4 years were retrospectively reviewed for clinical and imaging findings of middle lobe syndrome. Patients with previous lung surgery, preoperative chemo- or radiation therapy, or more extensive surgical resection were excluded. Patient demographics and symptoms, the surgical, pathologic and bronchoscopy reports, and pre- and post-operative chest imaging, to include 3D CT reconstructions and measurements of the middle lobe angles in a subset of patients, were retrospectively reviewed. RESULT: One hundred and twenty-eight patients met inclusion criteria. Ten (8%) had middle lobe syndrome based on symptoms and imaging features. Eight had severe middle lobe consolidation. Two had postoperative onset of wheezing, with middle lobe bronchial abnormality on CT. The pre- and postoperative middle lobe bronchial angles of 14 patients without middle lobe syndrome were compared to 10 patients with middle lobe syndrome. The middle lobe bronchus was completely obliterated postoperatively and could not be determined in 1 patient. There was no significant difference between the pre- and postoperative angles in patients with or without middle lobe syndrome. CONCLUSION: Middle lobe syndrome occurred in 8% of patients with right upper lobectomy. The preoperative middle lobe bronchial angle did not predict patients at risk for developing middle lobe syndrome.

Tracheobronchopathia osteochondroplastica - a 61-year-old female with middle lobe syndrome.

The authors present a case of a 61-year-old female patient suffering from tracheobronchopathia osteochondroplastica (TBO). Etiology of this unit is uncertain. TBO is characterised by presence of multiple nodules of various size, situated in the submucosa of the trachea and major bronchi. The course is usually benign, until lesion obstructs the bronchial lumen. In the presented case, occluded middle lobe bronchi resulted in peripheral atelectasis of the lung.

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.

Middle lobe syndrome: a rare presentation of allergic bronchopulmonary aspergillosis.

Allergic bronchopulmonary aspergillosis (ABPA) is a disease predominantly seen in susceptible asthmatic subjects, due to a hypersensitivity phenomenon caused by colonisation of the airways by Aspergillus species. Although collapse, both lobar and segmental due to mucoid impaction, is not uncommon in ABPA, a middle lobe syndrome (MLS) secondary to ABPA is rather an uncommon association. We report this rare and unusual clinical presentation in a 36-year-old male, who presented for evaluation of a "non resolving pneumonia". Imaging suggested the presence of a MLS and central bronchiectasis. Further investigations revealed that the patient met 6/8 of the essential diagnostic criteria for ABPA. Appropriate therapy with oral corticosteroids resulted in remarkable symptomatic improvement.

Chest MR imaging in the follow-up of pulmonary alterations in paediatric patients with middle lobe syndrome: comparison with chest X-ray.

PURPOSE: The authors evaluated the role of magnetic resonance (MR) imaging of the chest in comparison with chest X-ray in the follow-up of pulmonary abnormalities detected by computed tomography (CT) in paediatric patients with middle lobe syndrome. MATERIALS AND METHODS: Seventeen patients with middle lobe syndrome (mean age 6.2 years) underwent chest CT at the time of diagnosis (100 kV, CARE dose with quality reference of 70 mAs; collimation 24×1.2 mm; rotation time 0.33 s; scan time 5 s); at follow-up after a mean of 15.3 months, all patients were evaluated with chest MR imaging with a respiratory-triggered T2-weighted BLADE sequence (TR 2,000; TE 27 ms; FOV 400 mm; flip angle 150°; slice thickness 5 mm) and chest X-ray. Images from each modality were assessed for the presence of pulmonary consolidations, bronchiectases, bronchial wall thickening and mucous plugging. Hilar and mediastinal lymphadenopathies were assessed on CT and MR images. RESULTS: Baseline CT detected consolidations in 100% of patients, bronchiectases in 35%, bronchial wall thickening in 53% and mucous plugging in 35%. MR imaging and chest X-ray identified consolidations in 65% and 35%, bronchiectases in 35% and 29%, bronchial wall thickening in 59% and 6% and mucous plugging in 25% and 0%, respectively. Lymphadenopathy was seen in 64% of patients at CT and in 47% at MR imaging. CONCLUSIONS: Patients with middle lobe syndrome show a wide range of parenchymal and bronchial abnormalities at diagnosis. Compared with MR imaging, chest X-ray seems to underestimate these changes. Chest MR imaging might represent a feasible and radiation-free option for an overall assessment of the lung in the follow-up of patients with middle lobe syndrome.

Endobronchial tuberculosis presenting as right middle lobe syndrome: clinical characteristics and bronchoscopic findings in 22 cases.

PURPOSE: Endobronchial tuberculosis (EBTB) presenting as right middle lobe syndrome (RMLS) is an uncommon clinical condition. We investigated the clinical characteristics in patients with EBTB presenting as RMLS. PATIENTS AND METHODS: We retrospectively reviewed the records of 22 patients with EBTB presenting as RMLS who were diagnosed at our hospital from 2003 to 2006. RESULTS: Its occurrence was more common in females than males (F, 18; M, 4). The mean age was 70.3 +/- 8.5 years, and 17 patients were above the age of 65 years. Cough with sputum was the most common manifestation and 2 patients were asymptomatic. In bronchoscopic analysis, the most common finding was edematous-type EBTB, which was found in 15 patients, followed by actively caseating type in 6 and tumorous type in 1. Acid-fast bacilli (AFB) staining for bronchial washing fluid was positive in only 5 patients: 1 with edematous type and 4 with actively caseating type. Bronchoscopic biopsy showed chronic granulomatous inflammation in 16 patients. Follow-up chest X-ray after treatment showed complete disappearance of the lesion in 2 patients, more than 50% improvement in 5, less than 50% improvement in 5, and no change of lesion in 4. CONCLUSION: Edematous-type EBTB was the most common type of EBTB presenting as RMLS, and it usually occurred in elderly patients. Culturing for mycobacterium and histologic examination by bronchoscopy are necessary for proper diagnosis in these patients.

Lung cancer arising in association with middle lobe syndrome.

Middle lobe syndrome, caused mainly by benign inflammatory diseases, such as chronic bronchitis and bronchiectasis, is manifested clinically as a chronic cough with sputum production. The prognosis associated with this syndrome is considered good in most cases which are caused by chronic inflammatory diseases. A patient who developed lung cancer in the course of long-term treatment for right middle lobe syndrome is described. A 63-year-old woman was admitted to our hospital with complaints of right iliac bone pain. She had been treated for chronic bronchitis and bronchiectasis associated with middle lobe syndrome for 16 years before admission. Work-up of a lung adenocarcinoma originating from the right middle lobe disclosed bone metastasis to the illium. Tumorigenesis in association with middle lobe syndrome has not yet been reported, but this first reported case suggests the need to be alert to the possibility.

[Pulmonary Mycobacterium avium complex (MAC) disease showing middle lobe syndrome--pathological findings of 2 cases suggesting different mode of development].

Two different processes have been proposed for pathogenesis of Mycobacterium avium complex (MAC) disease which show the middle lobe syndrome: 1) middle lobe bronchiectasis followed by MAC infection and 2) MAC disease resulted in secondary bronchiectasis. Two surgical specimen from MAC cases showing middle lobe syndrome were studied histo-pathologically. The first case was a 60 year-old female with frequent bloody sputum, who had been diagnosed as bronchiectasis in her childhood. Pathological examination of the resected middle lobe showed prominent cylindric bronchiectasis in the indurated middle lobe, and epithelioid cell granulomas were scattered limited to the fibrous bronchial walls, without any granulomas in the lung parenchyma. These findings suggested a secondary infection of MAC to the non-specific pre-existed bronchiectasis. The second case of a 55 year-old female having repeated bloody sputum, who was diagnosed to be tuberculosis but no improvement with anti-tuberculosis drugs. Pathological examination of the middle lobe showed scattered epithelioid cell granulomas with lymphocytic infiltration in the lung parenchyma. A few epithelioid cell granulomas were also found in the mucosa of middle lobe bronchi. In this case, pulmonary MAC lesions seemed to precede the central bronchial lesion with later development of bronchiectasis. Summarizing above findings two different mode of pathogenesis ways may be considered; one is non-specific bronchiectasis followed by middle lobe MAC disease and the other is pulmonary MAC lesion in the middle lobe as a primary change.

Right middle lobe atelectasis associated with endobronchial silicotic lesions.

BACKGROUND: In a period of 18 months, we have encountered 4 cases of right middle lobe atelectasis associated with endobronchial silicotic lesions of right middle lobe bronchi. All patients had occupational exposure to mineral dusts (3 coal miners and 1 sand blaster) for months to decades. METHODS: The nature of the endobronchial silicotic lesions that caused the bronchial obstruction has been confirmed by endobronchial biopsies and energy-dispersive spectrometry of the lesions. Extrinsic compression has been excluded by careful radiographic and computed tomographic image analysis. RESULTS: The endobronchial silicosis does not appear to correlate with the degree of pneumoconiosis of the lung parenchyma. The endobronchial silicosis may cause bronchial obstruction in the absence of radiographic evidence of pulmonary silicosis. CONCLUSION: The endobronchial silicosis and consequent lung atelectasis may be associated with silica exposure.

Middle lobe syndrome: a clinicopathological study of 21 patients.

Middle lobe syndrome (MLS) is an uncommon lung disorder involving the right middle lobe and/or lingula and is characterized by a spectrum of clinical and pathological lesions ranging from recurrent atelectasis or pneumonias to bronchiectasis. Despite several series reporting the clinical features of MLS, histopathological descriptions are rare. We reviewed the clinical characteristics and pathological findings in 21 patients with MLS who underwent surgical resections. Six male and 15 female patients between the ages of 5 and 80 years (mean, 47 years) were studied. All patients were symptomatic and complained of chronic cough (8), hemoptysis (6), chest pain (4), dyspnea (3), or fever (2). The right middle lobe was involved in 11 patients, the lingula in four patients, and both right middle lobe and lingula in six patients. Chest radiographs, bronchograms, and/or computed tomography scans were available for review in 19 patients and showed consolidation (8), bronchiectasis (9), patchy infiltrates (5), and atelectasis (4) in various combinations. Pathological findings included bronchiectasis in 10 patients, chronic bronchitis/bronchiolitis with lymphoid hyperplasia in seven, patchy organizing pneumonia in six, atelectasis in five, granulomatous inflammation in five, and abscess formation in four. Three patients with granulomatous inflammation had associated atypical mycobacterial infection. Broncholithiasis was confirmed by pathological examination in one patient. No pathological cause for bronchial obstruction was identified in the remaining 20 patients, although one was thought to have had broncholithiasis on the basis of preoperative bronchoscopy. The presence of bronchiectasis, bronchitis or bronchiolitis, organizing pneumonia, or atelectasis in specimens from the right middle lobe or of lingula in the absence of an identifiable cause of bronchial obstruction should suggest a diagnosis of MLS.

Clinical findings in middle lobe syndrome and other processes of pulmonary shrinkage in children (atelectasis syndrome).

Processes of atelectasis and pulmonary shrinkage are not confined to the right middle lobe. This fact is illustrated by case reports of five of our nine such patients. All cases shared common clinical and morphologic similarities: congenital malformations of the bronchial skeleton, compression, and chronic inflammation produce comparable pulmonary morphology that always includes atelectasis. Atelectasic processes of longer duration require surgical resection; this led to cures in all the authors' patients.

Middle lobe syndrome.

A review of the major literature dealing with the middle lobe syndrome shows that benign inflammatory disease is the most common etiological factor (62%), with bronchiectasis responsible for at least a quarter of the patients in these series. Early workers indicated that carcinoma rarely originates in the right middle lobe; however, 22% of patients reviewed had malignant tumors as a cause of the syndrome. The original view that bronchial compression was the pathophysiological abnormality leading to development of the syndrome has been rejected by more recent authors. The focus has now turned to the relative isolation of the middle lobe, especially when a complete minor fissure is present. This isolation prevents the aerating effects of collateral ventilation of the upper lobe from reaching the middle lobe and thus impairs the clearing of secretions from the middle lobe bronchus. Bronchoscopy and bronchography are vital in the rational approach to this syndrome. Severe stenosis of the bronchus or tumor can be seen endoscopically in about 40% of patients, and bronchography will demonstrate an anatomical abnormality more than 70% of the time. Both the surgical and the medical approaches to therapy have been endorsed strongly by various authors in the 30 years since the syndrome was described. It now appears that bronchoscopy and, if need be, bronchography should be undertaken to rule out an endobronchial lesion. Timing of these studies will depend on the patient's age, with early examination advocated for the older patient at high risk for lung cancer. If there is reasonable evidence that the process is benign, medical management should be attempted. Lobectomy is performed if malignancy is suspected or if medical therapy fails.

Pathology of the middle lobe syndromes. A histopathological and pathogenetic analysis of sixty surgically-cured cases.

During the last 10 years the pathological substrate of the middle lobe syndrome was analysed in 60 surgically cured cases aged 7-59: there were 36 lung chronic suppurations, 20 neoplasias and 4 tuberculoses. In all these cases it was shown that, together with the specific lesions (infectious, tuberculosis, neoplastic) of bronchial walls and lung parenchyma a more or less obvious and high bronchial obstruction developed leading to obstructive pneumonitis with intralobular lipospongiocytosis. Investigated at different evolutive phases, this pneumonitis led to an extended restructuring of the lung tissue which occupied differently sized areas of the middle lobe. In the neoplastic and tuberculous cases, the restructured lung areas often included neoplastic emboli or infiltrations of neoplastic cells, or, respectively, remnant, reshuffled tuberculous lesions. None of cases presented zones of pure atelectasis.

Histopathological studies on the tumourlet of the lung with special reference to the cytogenesis of proliferating cells.

Eight foci of tumourlets of the lung and one allied lesion obtained from autopsy cases were histologically examined. The tumourlet of the lung consisted of epithelial cells and was considered to be a benign lesion. Small sized-lesion, uniformity of proliferating cells with very few mitosis and existence of associated lung lesions were documented as characteristic findings. However, the histopathogenesis of the tumourlet was not fully clarified. It was found that proliferating cells of tumourlets often show argyrophilia and contain numerous neurosecretory-like granules in their cytoplasm. These characteristics are very similar to Kultschitzky-like cells of the lung.