Correct!
3. Lung eosinophilia (bronchoalveolar lavage differential cell count > 25% eosinophils or predominance of eosinophils on open lung biopsy) is typical

Lung eosinophilia is characteristic of acute eosinophilic pneumonia, whereas peripheral blood eosinophilia is often lacking in these patients. Unlike chronic eosinophilic pneumonia, patients with acute eosinophilic pneumonia typically do not have a prior history of asthma, and usually do not suffer relapses from the disease following corticosteroid therapy. The imaging findings of acute eosinophilic pneumonia include rapidly progressive bilateral pulmonary opacities largely indistinguishable from the numerous other causes of acute lung injury or ARDS. The peripheral / subpleural opacities characteristic of chronic eosinophilic pneumonia are generally not a feature of acute eosinophilic pneumonia.

References

  1. Allen JN, Pacht ER, Gadek JE, Davis WB.Acute eosinophilic pneumonia as a reversible cause of noninfectious respiratory failure. N Engl J Med 1989; 31:321:569-77.
  2. Pope-Harman AL, Davis WB, Allen ED, et al. Acute eosinophilic pneumonia: A summary of 15 cases and a review of the literature. Medicine (Baltimore) 1996;75:334-42.
  3. Philit F, Etienne-Mastroïanni B, Parrot A, et al. Idiopathic acute eosinophilic pneumonia. Am J Respir Crit Care Med 2002;166:1235-9.
  4. Daimon T, Johkoh T, Sumikawa H, et. al. Acute eosinophilic pneumonia: Thin-section CT findings in 29 patients. Eur J Radiol 2008;65:462-7.