Bilateral Opaque Hemithorax



Bilateral Opaque Hemithorax


Dharshan Vummidi, MD

Jeffrey P. Kanne, MD



DIFFERENTIAL DIAGNOSIS


Common



  • Pulmonary Edema


  • Community Acquired Pneumonia


  • Pleural Effusion


Less Common



  • Diffuse Alveolar Hemorrhage


  • Drug Reaction


  • Acute Interstitial Pneumonia


  • Pneumocystis Pneumonia


  • Lung Contusion


  • Bronchioloalveolar Carcinoma


Rare but Important



  • Pulmonary Alveolar Proteinosis


ESSENTIAL INFORMATION


Key Differential Diagnosis Issues



  • Acute



    • Pulmonary edema


    • Acute interstitial pneumonia


    • Diffuse alveolar hemorrhage


    • Pleural effusion


    • Drug reaction


    • Pneumocystis pneumonia


    • Lung trauma


  • Chronic



    • Pleural metastasis


    • Bronchioloalveolar carcinoma


    • Pulmonary alveolar proteinosis


Helpful Clues for Common Diagnoses



  • Pulmonary Edema



    • Bilateral diffuse patchy or confluent air space consolidation



      • More central


      • “Bat-wing” or “butterfly” perihilar distribution


    • Septal (Kerley B) lines


    • Cardiomegaly common, especially with congestive heart failure


    • CT: Smooth interlobular septal thickening with basal predominance


    • Associated pleural effusions


    • Radiological response to treatment


  • Community Acquired Pneumonia



    • Diffuse bilateral disease usually from rapid spread of lobar pneumonia



      • Legionella


      • Staphylococcus


      • Pneumococcus


      • Viral


    • Immunocompromised patients at risk for disseminated infection


    • May develop acute respiratory distress syndrome (ARDS) or ARDS-like clinical picture


  • Pleural Effusion



    • Bilateral effusions often related to congestive heart failure


    • Meniscus


    • Minimal or no mediastinal shift


    • Associated collapse of underlying lung (compressive atelectasis)



      • Air bronchograms common


      • Uniform enhancement of lung parenchyma on contrast-enhanced CT or MR


Helpful Clues for Less Common Diagnoses



  • Diffuse Alveolar Hemorrhage



    • Usually related to capillaritis



      • Wegener granulomatosis


      • Microscopic polyangiitis


      • Systemic lupus erythematosus


      • Goodpasture syndrome


      • Drug reaction


    • Bilateral: Symmetric or asymmetric


    • Lung consolidation and ground-glass opacity



      • Peripheral sparing common


    • Elevated diffusing capacity (DLCO)


    • Bronchoalveolar lavage diagnostic


    • Usually clears within 7-10 days


  • Drug Reaction



    • Wide range of reactions



      • Diffuse alveolar damage


      • Diffuse alveolar hemorrhage


      • Organizing pneumonia


      • Eosinophilic pneumonia


      • Hypersensitivity reaction


    • Numerous causative agents



      • Chemotherapeutic agents most commonly implicated


      • Amiodarone: Deposition and reaction


  • Acute Interstitial Pneumonia



    • Diffuse alveolar damage



      • ARDS: Underlying cause known, common


      • Acute interstitial pneumonia (AIP): Idiopathic ARDS, rare


    • High mortality rate



    • Perihilar and basal predominant lung consolidation and ground-glass opacity



      • Air bronchograms common


      • Septal lines and pleural effusions uncommon


    • Slow evolution and response to treatment



      • Fibrosis may develop in spared areas


  • Pneumocystis Pneumonia



    • Underlying immunosuppression


    • AIDS



      • More insidious onset than with other forms of immunosuppression


      • CD4(+) T-cell count < 200 cells/µL


    • Perihilar or diffuse ground-glass opacity


    • May progress to consolidation


    • May develop upper lobe predominant thin-walled pneumatoceles


    • Pleural effusions are uncommon


  • Lung Contusion



    • Most common lung injury from blunt trauma


    • Hemorrhage into parenchyma


    • Marker of high-energy trauma


    • Radiography and CT



      • Nonanatomic distribution of consolidation and ground-glass opacity


      • Usually present on initial imaging


      • Should clear within 7 days


    • Extensive contusion associated with high mortality rate (> 25%)


  • Bronchioloalveolar Carcinoma



    • Slowly progressive lung consolidation


    • Bilateral involvement typical of multicentric or disseminated disease



      • Least common manifestation (solitary lung nodule and focal consolidation more common)


    • CT often shows mixed consolidation and ground-glass opacity



      • Crazy-paving and septal thickening less common


      • Dilated airways within consolidation: “Pseudocavitation”


Helpful Clues for Rare Diagnoses

Tags:
Aug 8, 2016 | Posted by in CARDIOLOGY | Comments Off on Bilateral Opaque Hemithorax

Full access? Get Clinical Tree
Get Clinical Tree app for offline access