Interstitial Lung Diseases PDF

Interstitial Lung Diseases By: Dr. Dagmawit, (CRI) Dr.Mesfine, (CRI) Moderator: Dr. Yimaj, MD, Chest imaging Subspecialist Idiopathic interstitial pneumonias  Idiopathic interstitial pneumonias IIP definition : Heterogenous group of diff...

Interstitial Lung Diseases By: Dr. Dagmawit, (CRI) Dr.Mesfine, (CRI) Moderator: Dr. Yimaj, MD, Chest imaging Subspecialist Idiopathic interstitial pneumonias  Idiopathic interstitial pneumonias IIP definition : Heterogenous group of diffuse lung disease occurring without known cause and associated with varying degrees of interstitial lung inflammation and fibrosis - Primary site of injury is interstitium 3  Classified based on histologic, clinical feature and radiologic manifestation by American Thoracic society and European Respiratory Society in 2013 The radiologic appearance parallels histologic appearance Multidisciplinary approach between clinical, pathologist and radiologist is important 4 5  USUAL INTERSTITIAL PNEUMONIA AND IDIOPATHIC PULMONARY FIBROSIS IPF is the idiopathic disease associated with the histologic pattern termed usual interstitial pneumonia. Histologically UIP shows spatial and temporal heterogeneity. UIP may be associated with several causes. – Collagen-vascular disease – Asbestosis – Drug toxicity – Radiation – Chronic hypersensitivity pneumonitis or – Familial pulmonary fibrosis. 6  UIP/IPF Radiographic Findings Bilateral reticular pattern Predominance at lower lung zones and subpleural lung regions 7  UIP/IPF Radiographic Findings Lateral film – More sensitive than the frontal. – Decreased lung volume seen. As fibrosis progress : – Coarse Reticulation – Honeycombing 8  UIP/IPF HRCT Findings Traction Honeycombi Reticulation bronchiectas ng is 9 UIP/IPF HRCT Findings 10 UIP/IPF HRCT Findings 11  UIP/IPF HRCT Findings Irregular reticular opacities Traction bronchiectasis Honeycombing GGO Mediastinal LAP 12  UIP/IPF Eg : GGO dominance Pleural plaques Biopsy not Histologic Do prone CT scan Conditional recommend correlation Histologic ed recommend correlation ed recommended 13  NONSPECIFIC INTERSTITIAL PNEUMONIA Less common than UIP. Histology: spatial and temporal homogeneity. Can be idiopathic or associated with diseases: – collagen-vascular diseases, hypersensitivity pneumonitis, drug toxicity, infection, or immunodeficiency. An association with collagen-vascular diseases is particularly common. 14  NSIP Clinically Present with symptoms similar to those of IPF Average age at diagnosis is 40 to 50 years. Respond to treatment with steroids Prognosis: Generally good This varies with the degree of fibrosis present. 15  Radiographic Findings of NSIP ill-defined opacity, ground- glass opacity, or consolidation predominantly involving the lower lung zones. reticular pattern or a combination of reticular and air-space patterns. In 10% or more of cases. the chest radiograph is normal. 16  HRCT Findings of NSIP ground-glass opacity (gray areas in c), irregular linear and reticular opacities (blue areas in c), micronodules (red areas in c), and microcystic honeycombing Peripheral with no obvious gradient 17  HRCT Findings of NSIP NSIP shows sparing of the immediate subpleural region (20% to 50% of cases) A finding that strongly suggests this diagnosis and helps distinguish NSIP from UIP. 19 HRCT Findings of NSIP 20  NSIP Based on proportions of inflammation and fibrosis, NSIP can be: cellular NSIP or – More inflammation – Less common – Better prognosis – Typically has GGO. fibrotic NSIP – interstitial fibrosis is seen in addition to mild inflammation – Traction bronchiectasis favors it. 21 22  Fibrotic nonspecific interstitial pneumonia. coarse reticular opacities and extensive traction bronchiectasis. sparing of the immediate subpleural lung. Honeycombing is absent despite the findings of fibrosis. 23  Fibrotic NSIP may resemble early UIP/IPF. A lung biopsy may be necessary In patients with known collagen-vascular disease, treatment is often undertaken without biopsy if the HRCT suggests or is consistent with NSIP. 24 25  UIP – Heterogenous involvement. – Honeycombing NSIP – Homogenous – GGO predominance – Subpleural reticulations – Micronodules – Microcysts (much smaller than UIP) 26 27  CRYPTOGENIC ORGANIZING PNEUMONIA Also known as bronchiolitis obliterans organizing pneumonia (BOOP), although OP is now the preferred term. – To avoid confusion with airway diseases such as constrictive bronchiolitis. Respiratory tract infection precedes their symptoms. Typical pts mean age is 55years with SOB, cough and fever over few weeks. Most of them had already abx. at previous consultation. Can be idiopathic or associated with other diseases like other IIPs. 28  COP Radiographic findings Patchy, unilateral or bilateral areas of air-space consolidation. Small nodular opacities or larger nodules in association with areas of air-space consolidation. Resembles pneumonic infiltrates. Consolidation could be peripheral, a pattern similar to that seen in chronic eosinophilic pneumonia. 29 COP 30  COP 71 yr old female pt with fever, SOB and non productive cough. Serology for viral agents, blood and sputum cultures and tumor markers normal. Initially treated with antibiotics but symptoms persisted. 31 COP 33  COP HRCT Findings The reversed halo sign, also known as the atoll sign central ground-glass opacity surrounded by denser consolidation of crescentic shape Seen in only 1/5th patients of COP. Central GGO septal inflammation; Peripheral rim  granulomatous tissue in air spaces. 34  COP HRCT Findings Irregular nodular areas of consolidation, Many occurring in relation to bronchi. Air bronchograms are visible within the opacities. An example of the atoll sign is visible. 35 COP HRCT Findings 36 COP HRCT Findings 37  ACUTE INTERSTITIAL PNEUMONIA AIP is the only entity among the IIPs with acute onset of symptoms. Is a fulminant disease of unknown cause, usually occurring in a previously healthy person AIP has been referred to as idiopathic ARDS. Mean age at presentation is 50. Rx : is largely supportive. 38  AIP RADIOGRAPHIC APPEARANCE Findings are similar to other causes of ARDS. Bilateral air-space consolidation or GGO. Can be diffuse (50%) or predominate in the upper (25%) or lower (25%) lung zones. Usually the CPA are spared. Honeycombing may be seen late in the disease. 39  AIP RADIOGRAPHIC APPEARANCE Diffuse, ill-defined areas of GGO and consolidation. CPA sparing 40  AIP HRCT Findings Early stages Patchy bilateral ground-glass opacity and consolidation Which tend to be diffuse or patchy at the dependent area of the lung. Late phase Architectural distortion, traction bronchiectasis, and honeycombing Seen at the non dependent areas of lung. 41 AIP HRCT Findings 42  Smoking related IIP RB , RB ILD and DIP Slight male predominance , middle age Clinical : asymptomatic , cough , crepitation, clubbing, PFT : restrictive Spectrum of same disease process Very good prognosis Treatment : smoking cessation , ? Steroid 43  RB ILD Found in all smokers If RB histologic findings are associated with pulmonary symptoms its RB ILD Histopathology : mild interstitial inflammatory changes around respiratory bronchioles and alveoli with mild thickening of alveolar septae but no significant fibrosis 44  Chest x-ray : normal or Upper lung/ diffuse reticulo nodular pattern HRCT 45 46  DIP Previously thought it was desquamation of epithelial cell but found out its accumulation of pigmented microphage within alveoli End spectrum of RB ILD Associated factors : smokers (90%) , infection , occupational exposures, LCH 47 Chest x-ray : patchy ground glass opacity with lower and peripheral lung predominancy HRCT 48 49 DIP… 50  LYMPHOID INTERSTITIAL PNEUMONIA LIP is characterized histologically by a dense lymphoid interstitial infiltrate consisting predominantly of lymphocytes. plasma cells, and histiocytes. Frequently occurs in association with collagen-vascular diseases, immunologic disorders and drug toxicity. More common in women. Patients present with of cough, SOB progressing over longstanding period of time. 51  LIP Radiographic Findings Variable, non-specific. Often, radiographs show a reticular pattern predominantly involving the lower lung zones. Less common abnormalities Nodular pattern or air-space consolidation. 52  LIP HRCT Findings Diffuse or patchy areas of GGO. Poorly defined centrilobular nodules Small, well-defined nodules with a perilymphatic distribution or septal thickening. Isolated cystic lung lesions, ( perivascular and sub pleural distribution.) 53 54  PLEUROPARENCHYMAL FIBROELASTOSIS Recently described, very rare condition Characteristic upper lobe predominant elastotic fibrosis of the pleura and adjacent parenchyma. The majority of cases are idiopathic 60% have progressive disease despite Rx; Death from the disease occurs in 40% of patients. 55  PPFE HRCT Findings Characteristic HRCT features are Predominantly upper lung zone pleural thickening subpleural reticulation Upper lobe volume loss and upward retraction of the hila. Architectural distortion, traction bronchiectasis, reticulation, and honeycombing may be seen. 56 PPFE HRCT Findings 57 58  Summary of Rules to be Remembered 1. Honeycombing with a basal and subpleural predominance, in the absence of a known disease or exposure UIP/IPF. 2. Concentric lower lobe ground-glass opacity with subpleural sparing and without honeycombing  NSIP. 3. Patchy or nodular subpleural or peri-bronchial consolidation COP. The atoll sign also suggests the dx. 4. ARDS with typical plain film or CT findings, without known cause AIP. 5. Diffuse or centrilobular ground-glass opacity in a smoker  DIP or RB-lLD. 6. Cystic air spaces or ground-glass opacity may represent LIP. LIP is usually associated with other diseases. 7. Reticulation, traction bronchiectasis, visceral pleural thickening PPFE 59 60 … 61 62