acute eosinophilic pneumonia diagnosis include eosinophils on BAL, pulmonary infiltrate, febrile illness

• related: acute and chronic eosinophilic pneumonia AEP and CEP
• tags: #permanent

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• acute to subacute febrile illness
• hypoxemic respiratory failure
• diffuse pulmonary opacities
• BAL showing >25% eosinophils (eosinophilic BAL points to atypical infections and atopic conditions, pulmonary eosinophilia differential diagnosis). ¹
• clinically, pulmonary infiltrates on chest imaging with peripheral eosinophilia over 1500 can be used as diagnosis ²

The revised diagnostic criteria for AEP include:

1. the acute onset of a febrile respiratory illness typically 5 to 7 days in duration and always ≤1 month
2. bilateral diffuse opacities on chest radiograph
3. hypoxemia with a PaO2 ≤60 mm Hg or an arterial saturation on room air <90%
4. a BAL with ≥25% eosinophils or a lung biopsy showing an eosinophilic pneumonia; and
5. the absence of other cause of pulmonary eosinophilia including drugs, toxins, and infectious pathogens. A recent onset of tobacco smoking or exposure to inhaled dusts may be present.

Acute respiratory failure is common, and two-thirds of patients will require mechanical ventilatory support. Peripheral blood eosinophilia is not a prominent feature of AEP, in contrast to CEP. However, BAL is characterized by a predominance of eosinophils (25% and usually higher, 37%-54% in some studies), and biopsy is rarely needed.¹

Links to this note

• acute and chronic eosinophilic pneumonia AEP and CEP
  • acute eosinophilic pneumonia diagnosis include eosinophils on BAL, pulmonary infiltrate, febrile illness

Footnotes

1. SEEK Questionnaires ↩ ↩²

2. Murray and Nadel Ch 96 Eosinophilic Lung Disease ↩