Current Respiratory Medicine Reviews - Volume 12, Issue 2, 2016

Background: The supraclavicular cyst of the thoracic duct is a very rare entity with approximately 27 publications in the English literature. Our aim was to describe the clinical radiological and histological characteristics of this rare entity and to highlight its pathogenesis through the description of 2 cases diagnosed in our Department and a review of the literature. Materials and Methods: The authors describe 2 new cases of idiopathic supraclavicular cyst well documented by radiologic, macroscopic and microscopic findings. The review of the literature was performed through the pubmed site using the keywords: cervical thoracic duct cyst, thoracic duct cyst. Conclusion: We report 2 cases of idiopathic cervical thoracic duct cyst. We found about 27 thoracic duct cysts that have been reported in the English literature till now. Magnetic resonance imaging and chemical analysis of the fluid obtained by preoperative fine-needle aspiration seem to be sufficient to make a primary diagnosis but the final and positive diagnosis must be made based on microscopic findings. The mainstay treatment is represented by surgical resection. Some cases treated successfully by a direct puncture sclerotherapy or even spontaneous regression have been reported in the literature.

Background: The role of the pleura in lung cancer dissemination is of paramount importance. This role was highlighted in the International Union Against Cancer staging system (commonly referred to as UICC) staging published in 2009. We tried to assess the prognostic impact of this classification. Materials and Methods: The present study is about 32 patients with adenocarcinoma who underwent lobectomy or pneumonectomy between 2005 and 2010. Patients with tumors without evidence of pleural invasion, with positive surgical margins or with other histologic subtype than adenocarcinoma were excluded. Overall survival curves were drawn using the Kaplan-Meier method. Differences in survival curves were compared using the log rank test. Differences were considered significant at p<0.05. Results: The patient group includes 28 men and 4 women with a mean age of 54 years. The 32 patients were classified into stage PL1 in 11 cases, PL2 in 14 cases and PL3 in 7 cases. The comparison of the survival curves showed a significant statistical difference (p=0,49) with a chisquare of 0.46 only between pl1 and pl2 groups. Conclusion: Our study showed an impact on the prognosis of a lung cancer when tumor cells had infiltrated the elastic layer of the pleura in the PL1 and PL2 diagnostic groups. This fact highlights the necessity for pathologists to use elastic stains in order to use this classification.

Background: Pleomorphic adenoma is a benign mixed tumor of salivary gland type. It has been rarely reported in the lung. Our aim is to report a rare case of primary pleomorphic adenoma of the lung with a misleading pattern and to perform a mini-review of the literature. Materials and Methods: We report a case of pleomorphic adenoma in a 12-yearold child with a mini-review of the literature in the site pubmed using the keywords: pleomorphic adenoma AND lung. Results: Our patient presented chest pain and fever. His past medical history was characterized by recurrent pneumonia. This case is interesting because it highlights a potential consequence of PA of the lung, which is bronchial dilatation. Besides, it puts emphasis on the diversity of the architectural patterns like acinar feature which was reported in our observation and which can be confusing.

Background: Bronchogenic cyst (BC) is a congenital cyst, which is frequently observed in the mediastinum. Its recurrence after surgical resection is very rare and mainly caused by the persistence of a part of the primary BC's wall. Objectives: Our aim was to present two cases of recurrent BC that were diagnosed in our Department. Besides, we targeted to perform a mini-review of similar cases reported in the English literature. Results: We describe 2 cases of mediastinal BC which recurred after 14 and 33 years. Both patients presented respiratory symptoms and the diagnosis of recurrent BC was suspected by the radiologic findings and confirmed by the microscopic examination. This phenomenon is very rare and has been initially reported by Craig Miller et al. in 1978. The cyst caused recurrent bronchial obstruction and compression of the superior vena cava and pulmonary artery. Since then, only ten cases have been reported so far (seven in the English literature, two in the Japanese literature and one in the French literature). Conclusion: Both cases reported highlights that despite the invasive nature of the recurrent BC, complete surgical resection must be always tried.

Currently, bronchodilators are the mainstay treatment of stable chronic obstructive pulmonary disease while systemic corticosteroids and antibiotics have a major role in COPD acute exacerbations. Inhaled N-acetylcysteine is a mucolytic that has a pharmacologic role in respiratory conditions associated with excessive thick mucus production. Additionally, N-acetylcysteine has been studied as an adjunct agent for the clinical management of COPD because of its antioxidant and inflammatory properties. This paper provides a narrative review of literature on the effect Nacetylcysteine has on clinical outcomes in stable COPD and in acute COPD exacerbations. Primary literature was sought utilizing databases using Medline (2004-present). The database was searched using the key MeSH terms N-acetylcysteine and COPD, COPD exacerbation. Current literature indicates in conjunction with standard drug regimen according to the COPD treatment guidelines, regular and high dose N-acetylcysteine (NAC) decrease frequency of exacerbations in stable COPD patient. Additionally, high dose N-acetylcysteine may improve airway obstruction in stable COPD patients. There is insignificant data for the use of N-acetylcysteine for patients experiencing acute exacerbations of COPD. Further studies should be performed as the overall benefits are still not fully established.

Obstructive sleep apnea syndrome (OSAS) is a common disorder characterized by recurrent episodes of upper airway obstruction resulting in oxygen desaturations and sleep disruption. OSAS is associated with an augmented risk for cardiovascular and cerebrovascular morbidity and mortality. Several mechanisms have been proposed to explain the association between OSAS and cardiovascular dysfunction. Low-grade systemic inflammation may contribute to the development of the cardiovascular and metabolic diseases associated with OSAS. The purpose of this review is to summarize current evidence on the association between OSAS and markers of systemic inflammation.

Broncholithiasis is a rare pulmonary condition caused predominantly by erosion of calcified perihilar and mediastinal lymph nodes into the bronchial lumen. The condition presents clinically in myriad ways including expectoration of stones, persistent cough, hemoptysis, pneumonia, obstructive respiratory failure, bronchoesophageal fistula or even massive hemorrhage. The clinical, radiographic, bronchoscopic and gross features have the potential for a mistaken diagnosis of bronchogenic carcinoma. Calcification of peri-hilar and mediastinal lymph nodes is most often caused by chronic granulomatous infections, particularly Mycobacterium tuberculosis and Histoplasma capsulatum. The stones act as nidus for colonization or superinfection with other microorganisms including Actinomyces spp. and Aspergillus spp. Bacterial, fungal, and mycobacterial special stains and microbiologic culture are essential in the work up of broncholithiasis.

The novel Antineoplastic agent can induce respiratory complications up to respiratory failure. As the incidence seems to be low, we tried to collect most of the information available aiming to highlight the problems such as wasting unnecessary resources and increasing medical professional’s awareness and its impact on patient care. Mechanisms of drug-associated lung injury are limited. There are no specific markers known to differentiate drug-associated interstitial lung disease from other pathologies. Therefore, we tried to collect possible mechanism pathways, histopathological patterns and factors discussed in literatures, directly or indirectly affecting lung tissue like, oxidant injury, vascular damage, and CNS depression. Risk factors are both dependent and independent, and interestingly Smoking is not a dependent risk factor and might decrease the likelihood of bleomycin pulmonary toxicity, It may even be protective. FREQUENCY In USA, more than 2 million cases of adverse drug reactions occur annually resulting in approximately 100,000 fatalities. Several studies reported that drug-induced pulmonary toxicity is under-diagnosed worldwide. We summarized the Novel agent causing pulmonary toxicity such as monoclonal antibodies, rapamycin analog, Tyrosine Kinase inhibitor, and the new immunotherapy (check points inhibitors) with toxicity type seen and percentage of patients reported. Clinical Manifestations and Diagnosis: The diagnosis of chemotherapy-induced pneumonitis should be considered when pneumonitis develops shortly after the initiation of treatment, there is no specific time of presentation, lack of an alternative explanation for respiratory failure, and the resolution of pneumonitis after corticosteroid treatment and withdrawal of the presumed agent. It is presented with various clinical syndromes/presentations may be confusing due to the different criteria used in the literature such as no specific laboratory or radiological test to diagnosis such complication Concurrent treatment with corticosteroids and antihistamines may not prevent the development of drug-induced pneumonitis. One unique presentation of antineoplastic agent-induced pneumonitis is so-called radiation recall pneumonitis as the chest imaging shows pulmonary infiltrates in exactly the same field of previously irradiated area. The differential diagnosis of antineoplastic agent-induced pneumonitis is extensive and in most of the cases is by exclusion of infectious, malignant, and cardiac diseases. Trans-bronchial or open-lung biopsy can be helpful in diagnosis. Imaging: The pattern and topographic distribution of opacities are highly variable. Occasionally, imaging features are suggestive. Treatment: Cessation of the apparent causative agent and initiating systemic corticosteroids. Different doses of methylprednisolone had been used according to severity ranged from 1g/day in severe cases to 60 mg every six hourly in mild to moderate cases. Laryngotracheal intubation, tracheostomy, esophagoscopy with fragmentation and lavage, Supportive care, and lung transplantation might be needed in some cases along with corticosteroid treatment. Re-exposure contraindicated and considered only if continuing treatment is essential to control a life-threatening underlying condition.

Background: Although exacerbations of chronic obstructive pulmonary disease produced by Pseudomonas aeruginosa infections are a major cause of death, the molecular mechanism that produces them is not well known. Here we focused on the energetic basis of dyspnoea, hypercapnia and acidosis symptoms. Methods and Findings: We used an in vivo exacerbation model exposing mice to cigarette smoke and LPS, to mimic emphysema and infections, and choline challenges to trigger exacerbations, that showed 31% increased in the airway resistance for naïve mice and 250% for smoke/LPS treatment. Tissue resistance was increased 32%, in naïve mice, and 169% for smoke/LPS treatment. A decreased tissue elastance, was confirmed by decreased collagen content and increased alveoli chord length. Consequently, the O2 demanded was 260% greater for smoke/LPS treated mice, to provide the energy required to pump the same volume of air then for naïve mice. The extra CO2 produced per ml of air pumped caused hypercapnia and acidosis by 4% decrease in pH. In addition, the bacteria grown with choline had a decrease of 67% in phosphate, 23% ATP and 85% phospholipids with an increase of 57% in polyphosphates, 50% carbohydrates, 100% LPS, consuming 45% less energy relative to the bacteria grown with succinate. Conclusion: choline, released by P. aeruginosa, triggers exacerbation symptoms by increasing lung resistance, O2 consumption and producing more pCO2 in blood with dyspnea, hypercapnia and acidosis. The energetic shift of decreased O2 bacterial demand and increased lung demand benefits the infection, thus restoring the energetic balance on the host will favor P. aeruginosa eradication.

Background: In diagnosing lung cancer, evidence-based guidelines recommend choosing the procedure that is safe, least invasive, and provides information about stage of the cancer together with the diagnosis. This study was done to assess the quality of practice patterns for diagnosing lung cancer. Methods: Retrospective review of patients diagnosed with lung cancer from January 2011 - December 2013. Results: Intra-parenchymal mass & mediastinal abnormality (discrete lymph node and mediastinal infiltration) were the common intra-thoracic radiological abnormality seen in 80 (64.5%) and 71 (57.2%) of patients respectively. TTNA was the most commonly performed procedure. No radiological difference in size & location of the mass was found in TTNA or bronchoscopy group. The yield of TTNA was higher than bronchoscopy (95% vs 68%, p=0.001) and the cost per patient was lower (S$581 vs S$1122, p=0.001). However TTNA correlated with missed opportunity of nodal staging in (52.5%) of patients, greater complication rate (48%), and delayed diagnosis by 14 (1-337) days. In bronchoscopy, the delay was shorter, and complication rate was lower. However 72.7% of patients missed opportunity of nodal staging, and the number of procedures needed per patient for diagnosis was higher (1.34 vs 1.05, p=0.02). Conclusion: Bronchoscopy was timely and safer technique than TTNA, but fraught with need for repeat procedures, and higher cost. TTNA on the other hand was more diagnostic and inexpensive than bronchoscopy but had high rate of complication, and delayed diagnosis. Both procedures had high rate of discordance with the guidelines & missed information regarding stage. Reserving TTNA for small peripheral lesions without mediastinal abnormality or bronchus sign, greater adoption of convex probe EBUS-TBNA, and availability of daily TTNA were the factors identified to improve quality.