Rojas, Carlos A.

An accurate differential diagnosis for diffuse lung disease can be confidently established by using a systematic approach to identify the predominant radiographic pattern, determine the distribution of disease, and assess for architectural or volume change.

Abstract Introduction Mediastinal masses may exhibit various clinical and pathological features. Posterior mediastinal lesions are often neurogenic, followed by lymphadenopathy, extramedullary hematopoiesis, paraspinal abscess, and rarely, foregut duplication cysts (prevalence: 0.122%). Given the rarity and diagnostic challenges, these masses are often biopsied, though may not be ideal. We present a case of esophageal duplication cyst (EDC). Case presentation A 33-year-old woman with mild intermittent asthma, had initially presented to an outside facility for chronic productive cough, episodic chest tightness and dyspnea both at rest and with exertion, inspiratory and expiratory wheezes. Despite multiple courses of prednisone for presumed asthma exacerbation, her symptoms persisted. An initial Computer Tomography (CT) Chest demonstrated a 5 x 4 x 3 cm mass within the visceral mediastinum. Bronchoscopy with endobronchial ultrasound and transbronchial needle aspiration of the mediastinal lymph nodes was nondiagnostic, showing scant lymphocytes and abundant mucin. Broad autoimmune, connective tissue disease, and infectious disease workups were negative, prompting referral to our facility. Physical exam and labs were unremarkable and pulmonary function testing showed no evidence of small airway obstruction. A High-Resolution CT Chest revealed a 3.1 x 3.7 x 4.5 cm noncalcified, well-circumscribed mass soft tissue density, adjacent to the esophagus with elevated Hounsfield units close to esophagus. Ultimately duplication cyst was suspected and Magnetic Resonance Imaging (MRI) with contrast showed high T1 and T2 signal within the lesion and no enhancement after contrast, deemed compatible with proteinaceous/hemorrhagic cyst (Figure 1 A-D). Biopsy was deferred given diagnostic MRI characteristics, and risk of secondary infection. The diagnosis of EDC was confirmed via multidisciplinary thoracic tumor board revision. Ultimately, she was referred for surgical resection. Discussion The incidence of EDC is 1 in 8,200, with a two-fold male prevalence over women. These patients may present with dysphagia, cough, stridor, pain, or arrhythmia since childhood, or may be entirely asymptomatic. EDCs can develop along the esophagus, with 90% lacking communication with the esophageal lumen. Although posterior mediastinal mass typically require biopsy to exclude malignancy, tissue biopsy should be avoided in cases with suspected duplication cyst given risk of infection, abscess formation and mediastinitis. Transesophageal endoscopic ultrasonography could further characterize the cyst, however MRI is considered the gold standard diagnostic modality. Conclusion MRI is the gold standard diagnostic modality of EDC. Biopsy should be avoided given the risk of infection. Clinicians should consider a broad differential for posterior mediastinal mass and avoid unnecessary invasive testing.

Background/Objective: To investigate the effect of mycophenolate mofetil (MMF) and rituximab (RTX) on pulmonary function test (PFT) results in a mixed cohort of patients with connective tissue disease-associated interstitial lung disease (CTD-ILD), longitudinally followed up for 1 year in a single academic center. Methods: Patients with CTD-ILD were identified in electronic medical records from 1 January 2009 to 30 April 2019. Prescribed MMF and RTX doses, dosage changes, and therapy plans were analyzed individually with improvement in PFT outcomes determined using multivariable linear regression models during 12-month follow-up. Results: Forty-seven patients with CTD-ILD, treated with MMF, RTX, or both, were included. Patients on combined MMF and RTX had worse PFT outcomes at baseline compared with patients on monotherapy. Substantial improvement was observed among all PFT outcomes from baseline to 12 months, regardless of medication dosage or therapy plans. The diffusing capacity of the lungs for carbon monoxide (DLCO) worsened by an average of 7.21 mL/(min*mmHg) (95% CI, 4.08–10.33; p < 0.001) among patients on RTX compared to combined therapy. Patients on higher doses of MMF at baseline experienced an average increase of 0.93 (95% CI, 0.04–1.82) units in DLCO from baseline to 6 months (p = 0.04) and a 2.79% (95% CI, 0.61–4.97%) increase in DLCO from 6 to 12 months (p = 0.02) within patients on concurrent RTX at 6-month follow-up. Conclusions: The treatment of CTD-ILD with MMF and/or RTX was associated with overall improvement in PFT outcomes. Combined therapy resulted in significant improvements in DLCO compared with monotherapy. Higher doses of MMF also provided greater improvements in DLCO.

Objective The aims of this study were to assess whether a relationship between anti–SSA-52 and interstitial lung disease (ILD) can be further defined, and to enhance screening, detection, and potentially guide treatment. Methods A historical cohort study of 201 patients was conducted at a single tertiary care center between January 1, 2016 and December 31, 2020. All included patients were anti–SSA-52 antibody positive. Chart review was performed for laboratory values, symptoms, pulmonary function tests, treatment, and imaging. Chest computed tomographies were reviewed by chest radiologists. Results Among anti–SSA-52 antibody–positive patients, ILD was found in 125 (62.2%) compared with 76 (37.8%) with no ILD (p = 0.001). For those with ILD, 78 (62.4%) were diagnosed with connective tissue disease (CTD)–associated ILD, 28 (22.4%) were diagnosed ILD only, and 19 (15.2%) met the criteria for interstitial pneumonia with autoimmune features. In patients with CTD-ILD, 18 (23.0%) had their ILD diagnosis made over 6 months before a CTD diagnosis, and an additional 43 (55.1%) had their ILD and CTD diagnosed within 6 months of each other (p < 0.001). Common computed tomography patterns were nonspecific interstitial pneumonia/organizing pneumonia overlap in 44 (35.2%), 25 (20.0%) nonspecific interstitial pneumonia, and 15 (12%) usual interstitial pneumonia. Twenty-eight (35.9%) had antisynthetase syndrome, followed by 16 (20.5%) with dermatomyositis, 10 (12.8%) with CTD overlap, and 6 (7.7%) with systemic scleroderma. Conclusions There was a significant association between anti–SSA-52 antibodies and ILD across a wide spectrum of rheumatological diagnoses. A significant portion of patients were diagnosed with ILD either at the same time or before their CTD diagnosis. Further study will be needed to assess effective treatment and response.

AbstractExpiratory central airway collapse (ECAC) is a pathology gaining recognition in the medical community due to its unspecific symptoms and diagnostic challenges. Its current gold standard for diagnosis, dynamic bronchoscopy, is invasive. Current non‐invasive techniques such as computed tomography (CT) protocols have shown limited reproducibility. We present a case of a 77‐year‐old man with suspected ECAC who underwent evaluation with two different expiratory CT protocols. The initial standard end‐expiratory CT could not detect airway collapsibility. However, dynamic bronchoscopy detected severe ECAC. Afterwards, we implemented a novel CT protocol, called dynamic forced expiratory CT (cinematic), comprising detailed, consecutive helical imaging of the central airway throughout the entire respiratory cycle, detecting severe ECAC, as proven by the earlier dynamic bronchoscopy. We hypothesize this may reduce the risks and need for performing multiple invasive procedures such as dynamic bronchoscopy. Extensive studies are required to evaluate the feasibility of its implementation for diagnosing ECAC.

Smooth muscle conditions of the chest have diverse clinical and imaging manifestations and may involve nearly every thoracic structure. Differentiation among these conditions requires the integration of clinical, radiologic, and histopathologic data. Histologic examination in conjunction with immunohistochemistry is essential for differentiation from other spindle cell neoplastic mimics. Familiarity with these entities will ensure the inclusion of smooth muscle conditions in the differential diagnosis of thoracic soft tissue lesions and potentially guide the clinician in appropriate management. We review the clinical, imaging, and histopathologic features of thoracic smooth muscle-related conditions organized by the anatomic structures affected.