Eosinophilia and skinGrunderkrankung + D72.1

Skin manifestations characterized by eosinophilic infiltration of the skin (e.g., accompanying insect bites, drug reactions, atopic dermatitis, or other neoplastic, immmunologic, or vasculitic abnormalities) and/or by hematoeosinophilia.

Eosinophilia is the elevation of the normal value of eosinophilic granulocytes in blood (normal value: 2-4% or 50-500/µl) or tissues. Hematoeosinophilia is present when the absolute number of eosinophils of 500/µl is exceeded (> 50% of total leukocytes).

The formerly used term "hypereosinophilia" (> 1500/µl) is no longer in use and is only used nomenclatorically in the so-called hypereosinophilia syndrome.

• Primary eosinophilia:
  • clonal eosinophilia
  • idiopathic eosinophilia.
• Secondary eosinophilia:
  • reactive eosinophilia.
• Clonal and idiopathic forms are grouped under primary eosinophilias. Clonal eosinophilias are predominantly hematologic neoplasms or myelodysplastic and -proliferative disorders.
• Reactive (or secondary) eosinophilias include all conditions in which a short-term or persistent eosinophilia always occurs in association with a detectable disease (e.g., parasitic disease, malignant tumors, other eosinophilic organ diseases such as eosinophilic esophagitis, gastritis, pneumonia, pancreatitis, myocarditis) or cause (e.g., drugs, radiation therapy) of nonclonal origin. Numerous dermatologic diseases are also included here (e.g., granuloma faciale).

The following is a list of diseases that are constantly or inconstantly accompanied by eosinophilia of the blood:

• Allergic diseases (group of atopic diseases):
  • Atopic eczema
  • Asthma, allergic (see below bronchial asthma)
  • Rhinoconjunctivitis allergica
  • Netherton 's syndrome (see below Ichthyosis linearis circumflexa) - often combined with atopic diseases
  • Urticaria (inconstant, no leading symptom)
  • Erythema exsudativum multiforme (inconstant).
• Parasitic diseases (especially when the parasites or their secretions penetrate the tissue):
  • Worm infections (for an overview see anthelmintics below).
  • Epizootic diseases ( scabies, pediculosis, pulicosis, trombidiosis, cereal scabies)
  • Insect bites caused by hymenoptera.
• Infectious diseases and parainfectious diseases:
  • Special fungal infections ( aspergillosis, coccidioidomycosis).
  • Diseases caused by protozoa (see zoonoses below)
  • Various viral infections ( HIV infection, measles, ringworm)
  • Scarlet fever
  • Spotted fever
  • Acrodermatitis papulosa eruptiva infantilis (Gianotti-Crosti syndrome).
• Blistering dermatoses:
  • Diseases of the pemphigus group (see below Pemphigus).
  • Diseases of the pemphigoid group (see below Pemphigoid)
  • Dermatitis herpetiformis (inconstant, often only histoeosinophilia)
  • Incontinentia pigmenti (Bloch-Sulzberger) (eosinophilia constant in the blister stage)
  • Stevens-Johnson syndrome (eosinophilia inconstant).
• Diseases of the hematopoietic system:
  • Hypereosinophilia syndrome/HES(high eosinophilia is obligate).
  • (Hyper-)eosinophilic dermatitis (high eosinophilia is obligate).
  • Episodic angioedema with eosinophilia (Gleich syndrome; constant and marked eosinophilia)
  • Eosinophilic leukemia
  • Erythroderma (with evidence of cutaneous T-cell lymphoma)
  • cutaneous B-cell lymphoma
  • cutaneous T-cell lymphoma
  • myeloma, multiple
  • lymphogranulomatosis, malignant
  • Mastocytosis
  • Histiocytoses, Langerhans cell histiocytoses (e.g. eosinophilic granuloma).
• Collagenoses:
  • Eosinophilic fasciitis (constant).
  • Eosinophilic myalgia syndrome (toxic-oil syndrome, hardly ever observed)
  • Dermatomyositis (inconstant)
  • Scleroderma, systemic (rather rare).
• Vasculitides:
  • Arteritis temporalis (inconstant).
  • Churg-Strauss syndrome (constant phenomenon)
  • Polyarteritis nodosa, systemic (inconstant)
  • Vasculitis, leukocytoclastic (non-IgA-associated) (mostly histoeosinophilia)
  • Wegener's granulomatosis (eosinophilia may be excessive).
• Endocrine disorders:
  • Addison's disease, M.
• Immunodeficiencies:
  • Episodic angioedema with eosinophilia.
  • Selective IgA defect
  • Wiskott-Aldrich syndrome
  • Sarcoidosis (in about 25% of patients)
  • Hyper IgE syndrome/HES(regular and pronounced).
• Various other diseases:
  • As a paraneoplastic syndrome (e.g., in various solid tumors).
    • Carcinomas of the colon, stomach, ovary, pancreas, cervix uteri, and thyroid; bronchial carcinomas.
  • DRESS
  • Dermatitis, exudative discoid lichenoid (oid-oid disease).
  • Panniculitis, pancreatic
  • Behçet, M.
  • Eosinophilic sterile pustulosis
  • Post scale azar dermatosis
  • Omenn syndrome
  • Hypermelanosis, nevoid, striate and whorl-shaped
  • Eosinophilic cellulitis (Wells syndrome, eosinophilia obligate)
  • Kimura's disease (angiolymphoid hyperplasia with eosinophilia)
  • Anticonvulsant hypersensitivity syndrome
  • Eosinophilic episodic angioedema (Gleich syndrome; constant and marked eosinophilia)
  • Erythema neonatorum
  • Eosinophilic anular erythema
  • Polymorphic and pruritic eosinophilic eruption during radiotherapy (Rueda et al.1999)
  • Granuloma faciale

Most common cause in Europe is allergies (> 20% of the population); increasingly, drugs are the cause of eosinophilia. Worldwide, parasitoses: depending on the region, up to 80% of the population may be affected.

Procedure in case of eosinophilia:

• Medical history (allergies, atopy, family history, medications, vaccinations, travel history).
• Physical examination with biopsies after several days of steroid abstinence (involved organs such as: skin, heart, lungs, GIT and others).
• Laboratory: blood count, ECP, stool tests (parasites), prick, RAST

Notice. An eosinophil count > 1500/ul is rather unusual for allergic diseases. The constellation of hematoeosinophilia and associated skin symptoms requires hematologic evaluation.

A rearrangement of the genes of the "platelet-derived growth-factor receptor" (PDGFR) alpha and beta can be detected in various clonal hemato-eosinophilia. By inhibition of certain cytoplasmic tyrosinases ( imatinib) influenced by this receptor, primary eosinophilia can be successfully treated.

1. Wozel G (2007) Eosinophilic dermatoses. Dermatologist 58: 347-360