Unilateral Pulmonary Consolidation
Dharshan Vummidi, MD
Jeffrey P. Kanne, MD
DIFFERENTIAL DIAGNOSIS
Common
Community Acquired Pneumonia
Bronchioloalveolar Carcinoma
Lung Contusion
Endobronchial Tumor
Less Common
Coccidioidomycosis
Blastomycosis
Diffuse Alveolar Hemorrhage
Eosinophilic Pneumonia
Pulmonary Emboli
Rare but Important
Lymphoma
Lipoid Pneumonia
Lobar Torsion, Lung
ESSENTIAL INFORMATION
Helpful Clues for Common Diagnoses
Community Acquired Pneumonia
Lobar
Bacterial: Streptococcus pneumoniae, H. influenzae, TB, and Legionella
Bronchopneumonia
Peribronchial, often multifocal consolidation
Possible endobronchial spread
Staphylococcus, Haemophilus, Pseudomonas, TB
Bronchioloalveolar Carcinoma
Slowly progressive lung consolidation
May increase in both size and density
Patients often treated for recurrent pneumonia in same lobe
CT often shows mixed consolidation and ground-glass opacity
Crazy-paving and septal thickening less common
Dilated airways within consolidation: “Pseudocavitation”
Lung Contusion
Most common lung injury from blunt trauma
Hemorrhage into parenchyma and air spaces
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
Endobronchial Tumor
Endobronchial soft tissue mass or broncholith obstructing bronchus
Primary lung carcinoma
Metastases: Melanoma, breast, renal cell, colon
Air bronchograms often absent within consolidation
CT may show fluid attenuation filling bronchi
Signs of volume loss, such as fissural or hilar displacement
Consider broncholith in presence of calcified lung nodules and calcified lymph nodes
Helpful Clues for Less Common Diagnoses
Coccidioidomycosis
Endemic in desert regions of southwestern USA
Single or multiple foci of lung consolidation
Nodules less common, may cavitate
Lymphadenopathy in 20% of patients
Pleural effusion in 10-20% of patients
Blastomycosis
Endemic in central and eastern USA along major rivers and around the Great Lakes
Single or multiple foci of lung consolidation
Slow to resolve or respond to therapy
Nodules and masses cavitate in 1/3 of patients
Lymphadenopathy uncommon
Pleural effusion in 20% of patients
Diffuse Alveolar Hemorrhage
Usually related to capillaritis
Wegener granulomatosis
Microscopic polyangiitis
Systemic lupus erythematosus
Drug toxicity
Unilateral less common than bilateral
Lung periphery often spared
Elevated diffusing capacity (DLCO)
Bronchoalveolar lavage diagnostic
Eosinophilic Pneumonia
Löffler syndrome
Simple pulmonary eosinophilia
Patients asymptomatic or present with fever and cough; spontaneously resolves
Transient or migratory solitary or multiple foci of lung consolidation
Other forms of eosinophilic pneumonia usually bilateral
Pulmonary Emboli
Consolidation from infarction, atelectasis, or hemorrhage
Solitary or multiple
Small pleural effusion may be present
Infarct on chest radiograph: Hampton hump
Infarct on CT: Peripheral wedge-shaped, unenhancing focus of consolidation with central lucencies
Resolves from periphery to center
Helpful Clues for Rare Diagnoses
Lymphoma
4% of lung malignancies
Non-Hodgkin lymphoma
More common than Hodgkin lymphoma
30% lung involvement
Unifocal or multifocal consolidation or nodules
Air bronchograms often present
Lipoid Pneumonia
Chronic mass-like consolidation and ground-glass opacity
Basal predominance (similar distribution to other causes of aspiration), unilateral or bilateral
Fat attenuation of consolidation on CT virtually diagnostic
Mineral oil aspiration most common cause (exogenous)
Lobar Torsion, Lung
Rare, usually occurs after lobectomy or transplant
Progressive lobar consolidation on imaging
Contrast-enhanced CT: Dense lobar consolidation with narrowing of airways and vessels
Derangement of normal bronchovascular configuration
Prompt identification and treatment required to prevent ischemic necrosis
Alternative Differential Approaches
Acute (< 2 weeks)
Community acquired pneumonia
Lung contusion
Fungal infection
Diffuse alveolar hemorrhage
Eosinophilic pneumonia
