<unk>  is diagnosed in one of three circumstances: when a complete blood count reveals increased eosinophils and a chest X-ray or computed tomography identifies abnormalities in the lungs, when a biopsy identifies increased eosinophils in lung tissue, or when increased eosinophils are found in fluid obtained by a bronchoscopy (bronchoalveolar lavage fluid). Association with medication or cancer is usually apparent after review of a person's medical history. Specific parasitic infections are diagnosed after examining a person's exposure to common parasites and performing laboratory tests to look for likely causes. If no underlying cause is found, a diagnosis of acute or chronic<unk>  is made based upon the following criteria. Acute<unk>  is most likely with respiratory failure after an acute febrile illness of usually less than one week, changes in multiple areas and fluid in the area surrounding the lungs on a chest X-ray, and eosinophils comprising more than 25% of white blood cells in fluid obtained by bronchoalveolar lavage. Other typical laboratory abnormalities include an elevated white blood cell count, erythrocyte sedimentation rate, and immunoglobulin G level. Pulmonary function testing usually reveals a restrictive process with reduced diffusion capacity for carbon monoxide. Chronic<unk>  is most likely when the symptoms have been present for more than a month. Laboratory tests typical of chronic<unk>  include increased levels of eosinophils in the blood, a high erythrocyte sedimentation rate, iron deficiency anemia, and increased platelets. A chest X-ray can show abnormalities anywhere, but the most specific finding is increased shadow in the periphery of the lungs, away from the heart. Differential diagnosis This includes: * Asthma * Environmental allergic reaction * Granulomatosis with polyangiitis * Allergic bronchopulmonary aspergillosis * Churg–Strauss syndrome * Loeffler's syndrome * Acute<unk>  * Chronic<unk>  (Carrington's disease) * Polyarteritis nodosa * Parasitic infections * Tropical pulmonary eosinophilia * Tuberculosis * Fungal infection * Sarcoidosis * Drug reaction with eosinophilia and systemic symptoms * Mastocytosis * Lymphoproliferative hypereosinophilic syndrome * Myeloproliferative hypereosinophilic syndrome
Eosinophilic pneumonia
Atypical pneumonia
Acute eosinophilic pneumonia
Lipid pneumonia
Cryptogenic organizing pneumonia
Lobar pneumonia
Parasitic pneumonia
Fungal pneumonia