Box 4 - Approach to evaluation of marked eosinophilia.

1) Eosinophil Determinations – Verify eosinophil count; estimate or get absolute eosinophil count

2) Medical History Obtain history of previous eosinophil counts Medical History ○ review medical history with emphasis placed on disorders know to be associated with eosinophilia including atopic disease Medication History ○ review recent and current medication history ○ discontinue any drugs known to be associated with eosinophilia ○ make a detailed list of all medications (including nutritional supplements, vitamins, herbal preparations) ○ Note any history of allergy to medications Travel/Geographic History ○ Review past history of travel to or residence in other countries ○ Review travel within indigenous country with emphasis on regions where particular eosinophilia-associated infections may be common Occupational/Recreational History ○ Review occupational and recreational exposures Dietary History ○ Review carefully; query dietary indiscretions, nutritional supplements Family History ○ Review whether others in family have eosinophilia suggesting a common exposure or familia nature of disease

Physical Examination Do a careful physical examination Close attention paid to skin, soft tissues, masses, lymphadenopathy

Initial Laboratory Evaluation Routine studies to assess general hematologic status (CBC, platelet count) studies to assess organ function (liver function tests, renal function tests, urinalysis, chest radiograph), inflammation (CRP/ESR), immune status (immunoglobulins, IgE).

Further Diagnostic Evaluations (based on initial laboratory findings or localizing symptoms) Tissue examination (biopsies) if necessary Specimen collection (CSF, sputum, bronchoalveolar lavage, stool, urine) that can identify the CT and MRI to define better focal lesions. Bone marrow aspirates and biopsies to assess fully the nature of the process underlying the eosinophilia. Additional disease-defining tests to exclude particular diagnoses (e.g. serum tryptase/cKIT mutations for systemic mastocytosis, antineutrophil cytoplasmic antibodies (ANCA) for CSS and other vasculitides, serologies for helminths