Chronic Eosinophilic Pneumonia
Differential Diagnosis
- Other eosinophilic pneumonias
- Known causes of chronic eosinophilic pneumonia
- Churg Strauss syndrome
- Idiopathic hypereosinophilic syndrome
- Langerhans cell histiocytosis
| Simple Eosinophilic Pneumonia | Acute Eosinophilic Pneumonia | Chronic Eosinophilic Pneumonia |
|---|---|---|
| Asymptomatic to mild symptoms | Fulminant respiratory insufficiency | Chronic dyspnea, cough |
| Blood eosinophils mildly elevated | Blood eosinophils normal to mildly elevated | Blood eosinophils >1000/mm3 |
| No direct treatment required | Steroid responsive, no relapses | Steroid responsive, 50% relapse |
Known causes of eosinophilic pneumonia must be ruled out
- Drugs
- Check history
- Skin rash suggestive
- Organisms
- Check travel history
- Check stool ova and parasites
- Check serology for fungi and parasites
- Culture and stain lavage and biopsy specimens
- Allergic bronchopulmonary aspergillosis
- Bronchiolocentric
- May have necrotizing granulomatous bronchiolitis
- Mucus plugs common
- Culture, serology, biopsy identification
| Churg-Strauss Syndrome | Acute Eosinophilic Pneumonia |
|---|---|
| Heart, kidneys, skin, gi, nervous system, other organs involved | Restricted to lung |
pANCA and anti-myeloperoxidase positive in 50% |
pANCA and anti-myeloperoxidase negative |
| Granulomatous vasculitis on lung biopsy | No granulomatous vasculitis |
| Idiopathic Hypereosinophilic Syndrome | Chronic Eosinophilic Pneumonia |
|---|---|
| Blood eosinophilia >1500/mm3 for 6 months | Blood eosinophilia >1000/mm3 |
| Heart, other organs involved | Restricted to lung |
| No asthma | Asthma may be seen |
| Langerhans Cell Histiocytosis | Chronic Eosinophilic Pneumonia |
|---|---|
| Predominantly interstitial process, intra-alveolar macrophages only focally present | Predominantly intra-alveolar process |
| Composed of Langerhans cells with variable numbers of eosinophils | Prominent eosinophils, no Langerhans cells |
| Produces stellate scars | Lacks scarring |
| Histiocytes with folded nuclei | Histiocytes with round nuclei |
| S100, CD1a, langerin positive | S100, CD1a, langerin negative |
