Etiology

Infection

Viral

• Human Immunodeficiency Virus (HIV) (see Human Immunodeficiency Virus, [[Human Immunodeficiency Virus]])
  • Epidemiology: peripheral eosinophilia in the setting of HIV is usually due to an associated drug, adrenal insufficiency, eosinophilic folliculitis, or other condition rather than due to the HIV itself
• Human T-Lymphotropic Virus-I (HTLV-I) (see Human T-Lymphotropic Virus Type I, [[Human T-Lymphotropic Virus Type I]])
• Human T-Lymphotropic Virus-II (HTLV-II) (see Human T-Lymphotropic Virus Type II, [[Human T-Lymphotropic Virus Type II]])

Bacteria

• Brucellosis (see Brucellosis, [[Brucellosis]])
  • Epidemiology: case reports [Eosinophilia and pneumonitis in chronic brucellosis: a report of two cases. Ann Intern Med. 1942;16:995-1001]
• Mycobacterium Simiae (see Mycobacterium Simiae, [[Mycobacterium Simiae]])
  • Epidemiology: [Acute eosinophilic pneumonia as a reversible cause of noninfectious respiratory failure. N Engl J Med. 1989;321:569- 574]
• Tuberculosis (see Tuberculosis, [[Tuberculosis]])
  • Epidemiology: unclear association with peripheral eosinophilia

Fungal

• Allergic Bronchopulmonary Aspergillosis (ABPA) (see Allergic Bronchopulmonary Aspergillosis, [[Allergic Bronchopulmonary Aspergillosis]])
• Allergic Bronchopulmonary Candidiasis (see Candida, [[Candida]])
• Basidiobolomycosis (see Basidiobolomycosis, [[Basidiobolomycosis]])
• Coccidioidomycosis (see Coccidioidomycosis, [[Coccidioidomycosis]])
  • Clinical: pronounced eosinophilia may be an early indicator of dissemination
• Cryptococcosis (see Cryptococcosis, [[Cryptococcosis]])
  • Epidemiology: [Cryptococcal pneumonia simulating chronic eosinophilic pneumonia. South Med J. 1995;88:845-846]
• Histoplasmosis (see Histoplasmosis, [[Histoplasmosis]])
• Paracoccidioidomycosis (see Paracoccidioidomycosis, [[Paracoccidioidomycosis]])

Parasitic

• Angiostrongyliasis Cantonensis
• Angiostrongyliasis Costaricensis
• Ascariasis (see Ascariasis, [[Ascariasis]])
• Cysticercosis (see Cysticercosis, [[Cysticercosis]])
• Cystoisosporiasis (see Cystoisosporiasis, [[Cystoisosporiasis]])
  • Cystoisospora (Isospora) Belli
• Dientamoebiasis (see Dientamoebiasis, [[Dientamoebiasis]])
  • Dientamoeba Fragilis
• Echinococcosis (see Echinococcosis, [[Echinococcosis]])
• Filariases
  • Dirofilariasis (see Dirofilariasis, [[Dirofilariasis]])
  • Loiasis
  • Lymphatic Filariasis
    • Brugia
    • Wuchereria
  • Mansonelliasis
    • Mansonella Ozzardi
    • Mansonella Perstans
    • Mansonella Streptocerca
  • Onchocerciasis (River Blindness) (see Onchocerciasis, [[Onchocerciasis]])
  • Tropical Pulmonary Eosinophilia (Occult Filariasis) (see Tropical Pulmonary Eosinophilia, [[Tropical Pulmonary Eosinophilia (Occult Filariasis)]])
• Flukes
  • Clonorchiasis (see Clonorchiasis, [[Clonorchiasis]])
  • Fascioliasis (see Fascioliasis, [[Fascioliasis]])
  • Fasciolopsiasis (Fasciolopsiasis, [[Fasciolopsiasis]])
  • Paragonimiasis (see Paragonimiasis, [[Paragonimiasis]])
  • Schistosomiasis (see Schistosomiasis, [[Schistosomiasis]])
• Gnathostomiasis
• Hookworm
  • Ancylostoma Duodenale
  • Necator Americanus
• Sarcocystosis (see Sarcocystosis, [[Sarcocystosis]])
  • Sarcocystis
• Scabies (see Scabies, [[Scabies]])
• Strongyloidiasis (see Strongyloidiasis, [[Strongyloidiasis]])
• Trichinosis (see Trichinosis, [[Trichinosis]])
• Visceral Larva Migrans (see Visceral Larva Migrans, [[Visceral Larva Migrans]])
  • Baylisascaris Procyonis
  • Toxocara Canis
  • Toxocara Catis

Pulmonary Infiltrates with Eosinophilia (see Pulmonary Infiltrates with Eosinophilia, [[Pulmonary Infiltrates with Eosinophilia]])

• Acute Eosinophilic Pneumonia (see Acute Eosinophilic Pneumonia, [[Acute Eosinophilic Pneumonia]])
• Acute Lung Transplant Rejection (Acute Cellular Lung Transplant Rejection) (see Acute Lung Transplant Rejection, [[Acute Lung Transplant Rejection]]): peripheral eosinophilia may occur with/without pulmonary infiltrates (as acute rejection may be detected by surveillance bronchoscopy with transbronchial biopsy prior to the development of pulmonary infiltrates)
• Allergic Bronchopulmonary Aspergillosis (ABPA) (see Allergic Bronchopulmonary Aspergillosis, [[Allergic Bronchopulmonary Aspergillosis]])
• Allergic Bronchopulmonary Candidiasis (see Candida, [[Candida]])
• Bronchocentric Granulomatosis (see Bronchocentric Granulomatosis, [[Bronchocentric Granulomatosis]])
• Chronic Eosinophilic Pneumonia (see Chronic Eosinophilic Pneumonia, [[Chronic Eosinophilic Pneumonia]])
• Churg-Strauss Syndrome (see Churg-Strauss Syndrome, [[Churg-Strauss Syndrome]])
• Dirofilariasis (see Dirofilariasis, [[Dirofilariasis]])
• Drug-Induced Pulmonary Eosinophilia (see Drug-Induced Pulmonary Eosinophilia, [[Drug-Induced Pulmonary Eosinophilia]])
• Eosinophilia-Myalgia Syndrome (see Eosinophilia-Myalgia Syndrome, [[Eosinophilia-Myalgia Syndrome]])
• Langerhans Cell Histiocytosis (see Langerhans Cell Histiocytosis, [[Langerhans Cell Histiocytosis]])
  • Clinical: peripheral eosinophilia is not commonly seen
• Hypereosinophilic Syndrome (see Hypereosinophilic Syndrome, [[Hypereosinophilic Syndrome]])
• Sarcoidosis (see Sarcoidosis, [[Sarcoidosis]])
• Simple Pulmonary Eosinophilia (Loffler’s Syndrome) (see Simple Pulmonary Eosinophilia, [[Simple Pulmonary Eosinophilia (Lofflers Syndrome)]])
• Tropical Pulmonary Eosinophilia (Occult Filariasis) (see Tropical Pulmonary Eosinophilia, [[Tropical Pulmonary Eosinophilia (Occult Filariasis)]])
• Visceral Larva Migrans (see Visceral Larva Migrans, [[Visceral Larva Migrans]])
• Other Infections
  • Brucellosis (see Brucellosis, [[Brucellosis]])
    • Epidemiology: case reports [Eosinophilia and pneumonitis in chronic brucellosis: a report of two cases. Ann Intern Med. 1942;16:995-1001]
  • Coccidioidomycosis (see Coccidioidomycosis, [[Coccidioidomycosis]])
    • Clinical: pronounced eosinophilia may be an early indicator of dissemination
  • Cryptococcosis (see Cryptococcosis, [[Cryptococcosis]])
    • Epidemiology: [Cryptococcal pneumonia simulating chronic eosinophilic pneumonia. South Med J. 1995;88:845-846]
  • Echinococcosis (see Echinococcosis, [[Echinococcosis]])
  • Histoplasmosis (see Histoplasmosis, [[Histoplasmosis]])
  • Human Immunodeficiency Virus (HIV) (see Human Immunodeficiency Virus, [[Human Immunodeficiency Virus]])
  • Mycobacterium Simiae (see Mycobacterium Simiae, [[Mycobacterium Simiae]])
    • Epidemiology: [Acute eosinophilic pneumonia as a reversible cause of noninfectious respiratory failure. N Engl J Med. 1989;321:569- 574]
  • Paragonimiasis (see Paragonimiasis, [[Paragonimiasis]])
  • Schistosomiasis (see Schistosomiasis, [[Schistosomiasis]])
  • Trichinosis (see Trichinosis, [[Trichinosis]])
  • Tuberculosis (see Tuberculosis, [[Tuberculosis]])

Malignancy

Myeloproliferative Neoplasm

• Acute Eosinophilic Leukemia (see Acute Myeloid Leukemia, [[Acute Myeloid Leukemia]])
• Chronic Eosinophilic Leukemia (see Chronic Eosinophilic Leukemia, [[Chronic Eosinophilic Leukemia]])
• Chronic Myeloid Leukemia (CML) (see Chronic Myeloid Leukemia, [[Chronic Myeloid Leukemia]])
• Myeloproliferative Neoplasms Associated with JAK2 Mutation
  • Essential Thrombocytosis (see Essential Thrombocytosis, [[Essential Thrombocytosis]])
  • Polycythemia Vera (see Polycythemia Vera, [[Polycythemia Vera]])
  • Primary Myelofibrosis (see Myelofibrosis-Myelophthisis, [[Myelofibrosis-Myelophthisis]])

Lymphoid Neoplasm

• Acute Lymphocytic (Lymphoblastic) Leukemia (see Lymphocytic, [[Acute Lymphocytic Leukemia]])
• Angioimmunoblastic T-Cell Lymphoma (AITL) (see Lymphoma, [[Lymphoma]])
• Autoimmune Lymphoproliferative Syndrome (ALPS) (see Autoimmune Lymphoproliferative Syndrome, [[Autoimmune Lymphoproliferative Syndrome]])
• B-Cell Lymphoma (see Lymphoma, [[Lymphoma]])
• Hodgkin’s Disease (see Hodgkins Disease, [[Hodgkins Disease]])
• Sezary Syndrome (see Sezary Syndrome, [[Sezary Syndrome]])
• T-Cell Leukemia/Lymphoma
• T-Cell Lymphoblastic Lymphoma

Other

• Adenocarcinoma
  • Gastrointestinal Tract: stomach, colon
  • Lung
  • Squamous Epithelium: cervix, vagina, penis, skin, nasopharyngeal, bladder
• Systemic Mastocytosis (see Systemic Mastocytosis, [[Systemic Mastocytosis]])

Allergic Disorders

• Allergic Rhinitis (see Allergic Rhinitis, [[Allergic Rhinitis]])
  • Clinical: mild-moderate eosinophilia
• Asthma (see Asthma, [[Asthma]])
  • Clinical: mild-moderate eosinophilia (<1500 eosinophils per uL)
• Atopic Dermatitis (see Atopic Dermatitis, [[Atopic Dermatitis]])
• Allergic Fungal Rhinosinusitis (see Chronic Rhinosinusitis, [[Chronic Rhinosinusitis]])
• Chronic Rhinosinusitis with Nasal Polyposis (see Chronic Rhinosinusitis, [[Chronic Rhinosinusitis]])

Immunodeficiency Syndrome

Primary Immunodeficiency

• Hyper IgE-Recurrent Infection Syndrome (Job’s Syndrome, Buckley-Job Syndrome) (see Hyper IgE-Recurrent Infection Syndrome, [[Hyper IgE-Recurrent Infection Syndrome]])
• IPEX
• Omenn Syndrome: severe form of combined immunodeficiency
• ZAP-70 Deficiency

Acquired Immunodeficiency/Inflammation

• Bone Marrow Transplant/Stem Cell Transplant with Graft vs Host Disease (see Graft vs Host Disease, [[Graft vs Host Disease]])
• Bullous Pemphigoid (see Bullous Pemphigoid, [[Bullous Pemphigoid]])
• Dermatitis Herpetiformis (see Dermatitis Herpetiformis, [[Dermatitis Herpetiformis]])
• Inflammatory Bowel Disease
• Pemphigus Vulgaris (see Pemphigus Vulgaris”>Pemphigus Vulgaris, [[Pemphigus Vulgaris]])
• Sarcoidosis (see Sarcoidosis, [[Sarcoidosis]])
  • Epidemiology: peripheral eosinophilia occurs in 41% of cases [MEDLINE]
• Serosal Surface Irritation
  • Chemical
  • Mechanical
  • Radiation
• Solid Organ Transplant Rejection

Rheumatologic Diseaase

• Behcet’s Disease (see Behcet’s Disease, [[Behcets Disease]])
• Buerger’s Disease (Thromboangiitis Obliterans) (see Buerger’s Disease, [[Buergers Disease]]): with eosinophilia of the temporal arteries
• Churg-Strauss Syndrome (Eosinophilic Granulomatosis with Polyangiitis, EGPA) (see Churg-Strauss Syndrome, [[Churg-Strauss Syndrome]])
• Dermatomyositis (see Polydermatomyositis, [[Polydermatomyositis]])
• Eosinophilic Fasciitis (Shulman’s Syndrome) (see Eosinophilic Fasciitis, [[Eosinophilic Fasciitis]])
• Eosinophilic Panniculitis (see Eosinophilic Panniculitis, [[Eosinophilic Panniculitis]])
• Immunoglobulin G4-Related Disease (see Immunoglobulin G4-Related Disease, [[Immunoglobulin G4-Related Disease]])
• Recurrent Cutaneous Necrotizing Eosinophilic Vasculitis
• Rheumatoid Arthritis (Severe) (see Rheumatoid Arthritis, [[Rheumatoid Arthritis]])
• Scleroderma (see Scleroderma, [[Scleroderma]])
• Sjogren’s Syndrome (see Sjogren’s Syndrome, [[Sjogrens Syndrome]])
• Systemic Lupus Erythematosus (SLE) (see Systemic Lupus Erythematosus, [[Systemic Lupus Erythematosus]])
• Wegener’s Granulomatosis (Granulomatosis with Polyangiitis) (see Wegener’s Granulomatosis, [[Wegeners Granulomatosis]])

Hypereosinophilic Syndrome (see Hypereosinophilic Syndrome, [[Hypereosinophilic Syndrome]]) [MEDLINE]

Myeloproliferative Type

• Myeloproliferative Hypereosinophilic Syndrome
  • PDGFRA Rearrangements
  • PDGFRB Rearrangements
  • FGFR1 Rearrangements
  • JAK Point Mutation/Translocation
  • Deletion of 4q12 -> FIPIL1-PDGFRA Fusion
• Chronic Eosinophilic Leukemia (see Chronic Eosinophilic Leukemia, [[Chronic Eosinophilic Leukemia]])
  • Clinical: clonal eosinophilia

Lymphocytic Type

• General Comments
  • Physiology: aberrant T-cells which produce IL-5
• Clonal T-Cells
• No T-Cell Clone

Familial Hypereosinophilic Syndrome

• Epidemiology: autosomal dominant
• Physiology: mapped to 5q 31-33
• Clinical: asymptomatic eosinophilia present from birth

Organ-Restricted Eosinophilic Disorders

• General Comments
  • Clinical: peripheral eosinophilia with single organ involvement (with eosinophilic organ infiltration)
• Chronic Eosinophilic Pneumonia (see Chronic Eosinophilic Pneumonia, [[Chronic Eosinophilic Pneumonia]])
• Eosinophilic-Associated Gastrointestinal Disorders (EGID)
  • Eosinophilic Esophagitis (see Eosinophilic Esophagitis, [[Eosinophilic Esophagitis]])
  • Eosinophilic Gastroenteritis (see Eosinophilic Gastroenteritis, [[Eosinophilic Gastroenteritis]])
• Eosinophilic Dermatitis/Cellulitis (Wells Syndrome) (see Eosinophilic Dermatitis, [[Eosinophilic Dermatitis]])
• Eosinophilic Intrinsic Asthma (see Asthma, [[Asthma]])
  • Clinical: mild-moderate eosinophilia (<1500 eosinophils per uL)
• Eosinophilic Sinus Disease

Associated Hypereosinophilic Syndrome

• General Comments
  • Clinical: marked peripheral eosinophilia
• Gleich Syndrome (Episodic Angioedema with Eosinophilia) (see Gleich Syndrome, [[Gleich Syndrome]])
• Inflammatory Bowel Disease
  • xxxx
  • xxxx
• Churg-Strauss Syndrome (Eosinophilic Granulomatosis with Polyangiitis, EGPA) (see Churg-Strauss Syndrome, [[Churg-Strauss Syndrome]])

Idiopathic Hypereosinophilic Syndrome

• Clinically Variable

Drug Rash with Eosinophilia and Systemic Symptoms (DRESS) (see Drug Rash with Eosinophilia and Systemic Symptoms, [[Drug Rash with Eosinophilia and Systemic Symptoms]])

• Allopurinol (Zyloprim) (see Allopurinol, [[Allopurinol]])
• Carbamazepine (Tegretol) (see Carbamazepine, [[Carbamazepine]])
• Cyclosporine A (see Cyclosporine A, [[Cyclosporine A]])
• Dapsone (see Dapsone, [[Dapsone]])
• Hydrochlorothiazide (HCTZ) (see Hydrochlorothiazide, [[Hydrochlorothiazide]])
• Lamotrigine (Lamictal) (see Lamotrigine, [[Lamotrigine]])
• Minocycline (see Minocycline, [[Minocycline]])
• Modafinil (Provigil) (see Modafinil, [[Modafinil]])
• Nevirapine (Viramune) (see Nevirapine, [[Nevirapine]])
• Penicillins (see Penicillins, [[Penicillins]])
• Phenobarbital (see Phenobarbital, [[Phenobarbital]])
• Phenytoin (Dilantin) (see Phenytoin, [[Phenytoin]])
• Sulfonamides (see Sulfonamides, [[Sulfonamides]])
  • Sulfasalazine (Azulfidine) (see Sulfasalazine, [[Sulfasalazine]])
• Ziprasidone (Geodon) (see Ziprasidone, [[Ziprasidone]])

Drugs

• Allopurinol (Zyloprim) (see Allopurinol, [[Allopurinol]])
  • Clinical
    • Drug Rash with Eosinophilia and Systemic Symptoms (DRESS) (see Drug Rash with Eosinophilia and Systemic Symptoms, [[Drug Rash with Eosinophilia and Systemic Symptoms]])
    • Hypersensitivity Vasculitis (see Vasculitis, [[Vasculitis]])
• Aspirin (Acetylsalicylic Acid) (see Acetylsalicylic Acid, [[Acetylsalicylic Acid]])
  • Clinical
    • Asthma with Nasal Polyps (see Asthma, [[Asthma]])
• Cephalosporins (see Cephalosporins, [[Cephalosporins]])
  • Clinical
    • Asymptomatic
• Dantrolene (see Dantrolene, [[Dantrolene]])
• Granulocyte-Monocyte Colony Stimulating Factor (GM-CSF) (see pharmx
  • Clinical
    • Soft Tissue Swelling
• Interleukin-2 (IL-2) (see Interleukin-2, [[Interleukin-2]])
  • Clinical
    • Soft Tissue Swelling
• L-Tryptophan (Eosinophilia Myalgia Syndrome) (see L-Tryptophan, [[L-Tryptophan]])
• Non-Steroidal Anti-Inflammatory Drugs (NSAID) (see Non-Steroidal Anti-Inflammatory Drug, [[Non-Steroidal Anti-Inflammatory Drug]])
  • Clinical
    • Drug-Induced Pulmonary Eosinophilia (see Drug-Induced Pulmonary Eosinophilia, [[Drug-Induced Pulmonary Eosinophilia]])
    • Gastroenterocolitis
• Penicillins (Semi-Synthetic) (see Penicillins, [[Penicillins]])
  • Clinical
    • Asymptomatic
    • Acute Interstitial Nephritis (see Acute Interstitial Nephritis, [[Acute Interstitial Nephritis]])
    • Hepatitis (see Drug-Induced Hepatotoxicity, [[Drug-Induced Hepatotoxicity]])
• Phenytoin (Dilantin) (see Phenytoin, [[Phenytoin]])
  • Clinical
    • Drug Rash with Eosinophilia and Systemic Symptoms (DRESS) (see Drug Rash with Eosinophilia and Systemic Symptoms, [[Drug Rash with Eosinophilia and Systemic Symptoms]])
    • Hypersensitivity Vasculitis (see Vasculitis, [[Vasculitis]])
• Ranitidine (Zantac) (see Ranitidine, [[Ranitidine]])
  • Clinical
    • Myocarditis (see Myocarditis, [[Myocarditis]])
• Tetracyclines (see Tetracyclines, [[Tetracyclines]])
  • Clinical
    • Hepatitis (see Drug-Induced Hepatotoxicity, [[Drug-Induced Hepatotoxicity]])

Other

• Acute Lung Transplant Rejection (Acute Cellular Lung Transplant Rejection) (see Acute Lung Transplant Rejection, [[Acute Lung Transplant Rejection]])
• Adrenal Insufficiency (see Adrenal Insufficiency, [[Adrenal Insufficiency]])
• Angiolymphoid Hyperplasia with Eosinophilia (Epithelioid Hemangioma)
• Cholesterol Emboli Syndrome (see Cholesterol Emboli Syndrome, [[Cholesterol Emboli Syndrome]])
• Contaminated Rapeseed Oil (see Contaminated Rapeseed Oil, [[Contaminated Rapeseed Oil]])
• Eosinophilic Pustular Folliculitis
• Eosinophilic Ulcer of the Oral Mucosa
• Hemodialysis (see Hemodialysis, [[Hemodialysis]])
  • Clinical: mild eosinophilia may occur
• Kimura Disease
• Nodules/Eosinophilia/Rheumatism/Dermatitis/Swelling (NERDS)
• Renal Transplant Rejection (see Renal Transplant, [[Renal Transplant]])

---

Diagnosis

Complete Blood Count (CBC) (see Complete Blood Count, [[Complete Blood Count]])

• Determination of Absolute Eosinophil Count: multiply percentage of eosinophils x total WBC count
  • Normal Absolute Eosinophil Count: 0-500 eosinophils per uL (<0.5 x 10 to the ninth/L)
• Eosinophilia
  • Low Eosinophil Count: more likely to be due to asthma or allergic rhinitis
  • High Eosinophil Count (>20k eosinophils/uL): more likely to be associated with a myeloproliferative malignancy

---

References

• Eosinophilia and pneumonitis in chronic brucellosis: a report of two cases. Ann Intern Med. 1942;16:995-1001
• Acute eosinophilic pneumonia as a reversible cause of noninfectious respiratory failure. N Engl J Med. 1989;321:569- 574
• Cryptococcal pneumonia simulating chronic eosinophilic pneumonia. South Med J. 1995;88:845-846
• Peripheral blood eosinophilia in association with sarcoidosis. Mayo Clin Proc 2000; 75(6)6: 586-590 [MEDLINE]
• Refining the definition of hypereosinophilic syndrome. J Allergy Clin Immunol. 2010 Jul;126(1):45-9. doi: 10.1016/j.jaci.2010.03.042 [MEDLINE]