Normal eosinophil count is less than 500 cells per microliter (cells/mcL). Normal value ranges may vary slightly among different laboratories.

Episodic angioedema associated with eosinophilia (Gleich syndrome23) is associated with marked episodic eosinophilia, angioedema, urticaria, pruritus, fever, weight gain, and often an elevated IgM level.

Asymptomatic eosinophilia has been associated most often with quinine, penicillins, cephalosporins, or quinolones. Pulmonary infiltrates with peripheral eosinophilia have been particularly associated with NSAIDs, sulfas, and nitrofurantoin.

Patients with allergic symptoms should have a nasal smear for eosinophilia and Gram stain. Patients with asthma symptoms should have sputum examination for eosinophilia. In suspected cases of medication and some parasitic infections, evaluation of urine sediment may be helpful.

If you think you have eosinophilic esophagitis, you’re likely to start by seeing your family doctor or a general practitioner. Your doctor may recommend that you see a specialist in treating digestive diseases (gastroenterologist) or an allergist.

Routine laboratory tests — A repeat complete blood count (CBC) with differential count to confirm the presence of eosinophilia, and a chemistry panel that includes electrolytes and liver function tests should be performed in all patients.

The degree of eosinophilia associated with different conditions can be characterized as mild, (500–1500 eosinophils per microliter), moderate (1500–5000 eosinophils per microliter), or severe (greater than 5000 per microliter). The term hypereosinophilia refers to eosinophil levels above 1500.

Eosinophilia can be constant or fluctuate over time, and any level of severity may be observed.