Lung imaging patterns in connective tissue disease-associated interstitial lung disease impact prognosis and immunosuppression response.

OBJECTIVES: Interstitial lung disease (ILD) in connective tissue diseases (CTD) have highly variable morphology. We aimed to identify imaging features and their impact on ILD progression, mortality and immunosuppression response. METHODS: Patients with CTD-ILD had high-resolution chest computed tomography (HRCT) reviewed by expert radiologists blinded to clinical data for overall imaging pattern (usual interstitial pneumonia [UIP]; non-specific interstitial pneumonia [NSIP]; organizing pneumonia [OP]; fibrotic hypersensitivity pneumonitis [fHP]; and other). Transplant-free survival and change in percent-predicted forced vital capacity (FVC) were compared using Cox and linear mixed effects models adjusted for age, sex, smoking, and baseline FVC. FVC decline after immunosuppression was compared with pre-treatment. RESULTS: Of 645 CTD-ILD patients, the frequent CTDs were systemic sclerosis (n = 215), rheumatoid arthritis (n = 127), and inflammatory myopathies (n = 100). NSIP was the most common pattern (54%), followed by UIP (20%), fHP (9%), and OP (5%). Compared with UIP, FVC decline was slower for NSIP (1.1%/year, 95%CI 0.2, 1.9) and OP (3.5%/year, 95%CI 2.0, 4.9), and mortality was lower for NSIP (HR 0.65, 95%CI 0.45, 0.93) and OP (HR 0.18, 95%CI 0.05, 0.57), but higher in fHP (HR 1.58, 95%CI 1.01, 2.40). The extent of fibrosis also predicted FVC decline and mortality. After immunosuppression, FVC decline was slower compared with pre-treatment in NSIP (by 2.1%/year, 95%CI 1.4, 2.8), with no change for UIP or fHP. CONCLUSION: Multiple radiologic patterns are possible in CTD-ILD, including a fHP pattern. NSIP and OP were associated with better outcomes and response to immunosuppression, while fHP had worse survival compared with UIP.

Integration and Application of Radiologic Patterns From Clinical Practice Guidelines on Idiopathic Pulmonary Fibrosis and Fibrotic Hypersensitivity Pneumonitis.

BACKGROUND: Clinical practice guidelines separately describe radiologic patterns of usual interstitial pneumonia (UIP) and fibrotic hypersensitivity pneumonitis (fHP), without direction on whether or how to apply these approaches concurrently within a single patient. RESEARCH QUESTION: How can we integrate guideline-defined radiologic patterns to diagnose interstitial lung disease (ILD) and what are the pitfalls associated with described patterns that require reassessment in future guidelines? STUDY DESIGN AND METHODS: Patients from the Canadian Registry for Pulmonary Fibrosis underwent detailed reevaluation in standardized multidisciplinary discussion. CT scan features were quantified by chest radiologists masked to clinical data, and guideline-defined patterns were assigned. Clinical data then were provided to the radiologist and an ILD clinician, who jointly determined the leading diagnosis. RESULTS: Clinical-radiologic diagnosis in 1,593 patients was idiopathic pulmonary fibrosis (IPF) in 26%, fHP in 12%, connective tissue disease-associated ILD (CTD-ILD) in 34%, idiopathic pneumonia with autoimmune features in 12%, and unclassifiable ILD in 10%. Typical and probable UIP patterns corresponded to a diagnosis of IPF in 66% and 57% of patients, respectively. Typical fHP pattern corresponded to an fHP clinical diagnosis in 65% of patients, whereas compatible fHP was nonspecific and associated with CTD-ILD or IPAF in 48% of patients. No pattern ruled out CTD-ILD. Gas trapping affecting > 5% of lung parenchyma on expiratory imaging was an important feature broadly separating compatible and typical fHP from other patterns (sensitivity, 0.77; specificity, 0.91). INTERPRETATION: An integrated approach to guideline-defined UIP and fHP patterns is feasible and supports > 5% gas trapping as an important branch point. Typical or probable UIP and typical fHP patterns have moderate predictive values for a corresponding diagnosis of IPF and fHP, although occasionally confounded by CTD-ILD; compatible fHP is nonspecific.

Canadian Association of Radiologists/Canadian Association for Interventional Radiology/Canadian Society of Thoracic Radiology Guidelines on Thoracic Interventions.

Thoracic interventions are frequently performed by radiologists, but guidelines on appropriateness criteria and technical considerations to ensure patient safety regarding such interventions is lacking. These guidelines, developed by the Canadian Association of Radiologists, Canadian Association for Interventional Radiology and Canadian Society of Thoracic Radiology focus on the interventions commonly performed by thoracic radiologists. They provide evidence-based recommendations and expert consensus informed best practices for patient preparation; biopsies of the lung, mediastinum, pleura and chest wall; thoracentesis; pre-operative lung nodule localization; and potential complications and their management.

Pulmonary Apical Cap as a Potential Risk Factor for Pleuroparenchymal Fibroelastosis.

Pleuroparenchymal fibroelastosis (PPFE) is a progressive and frequently fatal interstitial lung disease that involves the upper lobes. Although its cause remains unknown, the histopathologic evidence underlying PPFE bears striking resemblance to that of the pulmonary apical cap (PAC), a relatively common and benign entity. We describe the case of a patient with PAC that evolved into distinctly asymmetric PPFE over 6 years after unilateral surgical lung injury. Given the histologic similarity between these two conditions, we propose that these two entities underlie common biologic pathways of abnormal response to lung injury, with the presence of a PAC increasing susceptibility to the development of PPFE in the face of ongoing inflammatory insults. This case describes the histopathologic evolution of PAC to PPFE before and after an inciting injury.

Computed tomography-guided platinum microcoil lung surgery: A cross-sectional study.

OBJECTIVE: The study objective was to provide a 5-year update on our tertiary-level institutional experience with computed tomography-guided platinum microcoil lung surgery. METHODS: A retrospective cross-sectional study was conducted. All patients admitted to the Thoracic Service at Vancouver General Hospital to undergo computed tomography-guided microcoil lung surgery were included. Key primary outcome variables were successful nodule localization and severity of adverse events associated with placement. Secondary outcomes included nodule characteristics on preoperative computed tomography chest and nodule surgical pathology. Continuous variables were reported as mean (± standard deviation), and counts were reported as proportions n (%). RESULTS: A total of 97 lung nodules were resected in 92 patients. Mean age was 65.3 (±10.6) years, and 59 (61%) were female. All 97 nodules (100%) were successfully localized using video-assisted thoracic surgery wedge resection. There were 59 cases (60.8%) of placement-related events noted on computed tomography of the chest. All were minor and self-limited in nature and did not require treatment: pneumothorax 45 (46.4%), lung hematoma 18 (18.6%), dislodgement 4 (4.1%), and hemoptysis 2 (2.1%). Mean nodule diameter was 13.2 mm (±6.7). Density was nonsolid in 27 (27.8%) and semi-solid in 27 (27.8%). There was a single case of positive surgical margin, and 4 (4.1%) went on to completion lobectomy. Non-small lung cancer was identified in 66 nodules. CONCLUSIONS: Computed tomography-guided platinum microcoil lung surgery is safe with a favorable clinical adverse event profile and is suitable for poor-risk patients. The method is efficient, yielding 100% diagnostic localization in our 5-year update. It eliminates the need for thoracotomy and palpation to localize worrisome subpleural tiny nodules. It is ideal for the management of changing nodules concerning for early lung cancer and diagnosis of small indeterminate lung nodules or metastases.

Inflammatory pseudotumours in the abdomen and pelvis: a pictorial essay.

Inflammatory pseudotumours are uncommonly encountered lesions in the abdomen and pelvis that often present with variable and nonspecific imaging features. They may mimic other more common lesions, including malignancy. Within the appropriate clinical context, inflammatory pseudotumours merit consideration in the differential diagnosis of soft-tissue masses within the abdomen and pelvis. A preoperative diagnosis of inflammatory pseudotumour, established through biopsy, may help to differentiate this benign entity from malignancy. In this article, we reviewed the imaging features of inflammatory pseudotumours of the abdomen and pelvis, including liver, spleen, bowel, retroperitoneum, kidney, bladder, uterus, and adnexa.