Pulmonary Eosinophilia and CXR changes
Related Subjects: Asthma
|Acute Severe Asthma
|Eosinophilic granulomatosis (Churg Strauss)
|Loffler's syndrome (Pulmonary Eosinophilia)
|Pulmonary Eosinophilia and CXR changes
|Drug Reaction Eosinophilia Systemic Symptoms
🫁 Pulmonary Eosinophilia describes a spectrum of lung disorders where eosinophils infiltrate the lung parenchyma.
It can mimic infection or interstitial lung disease and requires careful differentiation.
📸 Common CXR Changes
- 🌐 Peripheral Infiltrates – bilateral, patchy opacities (classic "photographic negative of pulmonary oedema").
- 🌫️ Ground-glass opacities – hazy infiltrates with preserved vascular markings (active inflammation).
- 🕸️ Reticular pattern – mesh-like, often in chronic eosinophilic pneumonia (fibrosis + interstitial thickening).
- ⬜ Consolidation – alveolar filling, usually in chronic forms.
- ⭕ Normal CXR – possible in early/mild cases; does not exclude diagnosis.
🖼️ Other Imaging Findings
- HRCT – more sensitive: shows GGOs, mosaic attenuation, septal thickening, crazy paving.
- Crazy Paving – GGO + septal thickening, looks like paving stones.
- ⬆️ Upper Lobe Predominance – especially in chronic eosinophilic pneumonia.
📊 Causes of Severe Eosinophilia (>5 × 10⁹/L)
- 🌿 ABPA – hypersensitivity to Aspergillus in asthmatics/CF; IgE ↑, bronchiectasis.
- 🟤 Chronic Eosinophilic Pneumonia (CEP) – progressive cough, weight loss, peripheral infiltrates.
- ❤️ Hypereosinophilic Syndrome (HES) – persistent eosinophilia with end-organ damage (heart, lung, gut).
- ⚡ Acute Eosinophilic Pneumonia (AEP) – acute hypoxaemic respiratory failure; BAL eosinophils >25%.
- 🪱 Löffler’s Syndrome – transient infiltrates with parasitic infections (e.g., Ascaris).
- 💊 Drug-induced Pneumonitis – e.g., nitrofurantoin, minocycline, phenytoin.
- 🧬 Eosinophilic Leukaemia – clonal proliferation; confirmed with marrow/genetic studies.
📉 Causes of Mild–Moderate Eosinophilia (0.5–2.0 × 10⁹/L)
- 🩸 EGPA (Churg-Strauss) – asthma, sinusitis, neuropathy, ANCA+ vasculitis.
- 🕯️ Hodgkin’s Lymphoma – paraneoplastic eosinophilia with “B” symptoms.
- 🪱 Parasitic Infections (low burden) – Strongyloides, hookworm, Trichinella.
🔬 Diagnosis
- 🧪 Bloods: eosinophils >0.5 × 10⁹/L, IgE often elevated.
- 💉 BAL: eosinophils >25% diagnostic for eosinophilic pneumonia.
- 🖼️ HRCT: GGOs, crazy paving.
- 🩺 Lung Biopsy: tissue eosinophilia, fibrosis in chronic cases.
- 💩 Stool Examination: detect ova/larvae if parasitic cause suspected.
💊 Management
- 🌟 Corticosteroids – mainstay for idiopathic/autoimmune cases (CEP, EGPA, AEP).
- ⚕️ Underlying cause treatment:
– Stop offending drug 💊
– Antiparasitic therapy (albendazole, ivermectin) 🪱
– Treat malignancy/lymphoma 🧬
- 📅 Monitor with repeat CXR/CT + eosinophil counts.
3 Clinical Cases - Pulmonary Eosinophilia & Chest X-ray Findings 🫁🧪
- Case 1 - Allergic Bronchopulmonary Aspergillosis (ABPA) 🌿: A 32-year-old asthmatic with recurrent exacerbations presents with cough productive of brown mucus plugs and wheeze. Bloods: eosinophilia, raised IgE. CXR: fleeting pulmonary infiltrates in the upper lobes, central bronchiectasis. Teaching: ABPA occurs in asthmatics/CF patients sensitised to Aspergillus. Radiology shows transient, migratory opacities. Treat with steroids ± antifungals (itraconazole).
- Case 2 - Tropical Pulmonary Eosinophilia 🦟: A 29-year-old man from India develops nocturnal cough, wheeze, and weight loss. Eosinophils very high (>3.0 × 10⁹/L). CXR: diffuse miliary-like nodular infiltrates, especially mid-zones. Teaching: Caused by hypersensitivity to filarial parasites (e.g. Wuchereria bancrofti). Characteristic marked eosinophilia with reticulonodular CXR. Responds dramatically to diethylcarbamazine.
- Case 3 - Chronic Eosinophilic Pneumonia 📸: A 48-year-old woman with atopy presents with progressive dyspnoea, weight loss, and night sweats. Bloods: eosinophilia. CXR: dense, bilateral peripheral infiltrates (the “photographic negative of pulmonary oedema”). Teaching: Chronic eosinophilic pneumonia shows striking peripheral consolidations on CXR. Responds rapidly to corticosteroids but relapses are common.
