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Hypereosinophilic syndrome

Updated : February 14, 2024





Background

Blood granulocytes called “eosinophils” produce cytoplasmic granules that bond with acidic dyes like “eosin” and possess basic proteins. They are derived from bone marrow, and GM-CSF, IL-5, and IL-3 promote their synthesis. They circulate for 4.5 to 8 hours at a time. They can stay in tissues for eight to twelve days, especially in the digestive and respiratory tracts.

Below 5 percent of circulating leukocytes are eosinophils. A rise in the number of circulating eosinophils above 500/mm3 is known as eosinophilia. Eosinophilia can be classified as mild (500 to 1500/mm3), medium (150 to 5000/mm3), or serious (>5000/mm3), depending on the values.

Absolute eosinophil levels of more than 1500/mm3 on two separate occasions, at least a month apart, or demonstrable tissue eosinophilia are both considered to be symptoms of hypereosinophilic syndrome.

Epidemiology

Eosinophilia frequency and incidence are not well understood. Eosinophilia is not preferential for any one sex. Depending on the reason, there might be geographic implications, though. Tropical nations are more likely to experience parasite infestations.

In affluent nations, allergic diseases are quite frequent. The diagnosis of idiopathic hypereosinophilia is generally made between the ages of 20 and 50, while it has been known to occur at extreme ages at both extremes of the curve.

Anatomy

Pathophysiology

Eosinophils differentiate in the bone marrow, where they also stop developing further after leaving. They live primarily outside of the vasculature in tissues. Eosinophils are drawn into the affected tissues in eosinophil-related diseases. Eosinophilopoiesis and eosinophil stimulation are brought on by IL-5 synthesis and immunological responses mediated by T helper-2 cells.

IL-5 is a key cytokine involved in eosinophil generation and activation. When eosinophils are activated, they degranulate and then discharge cationic proteins into the site tissues via which they work.

The host wall may also sustain harm from these liberated proteins, which may also be proteolytic enzymes. In order to maintain homeostasis and regulate the immune system, eosinophils also release cytokines, including IL-10 as well as IL-14.

Etiology

Primary and secondary eosinophilia is also possible:

Primary factors:

  • CEL – chronic eosinophilic leukemia
  • PDGFRA, PDGF-AB, and FGFR1 gene rearrangements in lymphoid and myeloid cancers
  • Eosinophilia hereditary
  • Hypereosinophilic syndrome without a known cause

Secondary Factors:

  • Ancylostomiasis, cysticercosis, ascariasis, hydatid cyst (echinococcosis), strongyloidiasis, schistosomiasis, toxocariasis (visceral larva migrans), and trichinellosis are some examples of parasite infestations.
  • Bacterial and fungal infections: scarlet fever, occasionally chronic tuberculosis, disseminated histoplasmosis, coccidioidomycosis, and bronchopulmonary aspergillosis.
  • Allergic diseases: hay fever, bronchial asthma, Stevens-Johnson condition, DRESS syndrome, food, and allergy to drugs.
  • Skin disorders: Atopic dermatitis, Mycosis fungoides, eczema, Sezary syndrome, pemphigus.
  • Host versus graft reaction
  • Chrug-Strauss syndrome and eosinophilic myalgia syndrome are examples of connective tissue illness.
  • Other: eosinophilic gastroenteritis, pancreatitis, reactive pulmonary eosinophilia, and tropical eosinophilia.

Genetics

Prognostic Factors

Depending on a number of variables, including eosinophilia’s underlying etiology, the existence of organ damage, its subtype, and the timing of intervention, the prognosis might range from a minor illness to a catastrophic consequence.

Clinical History

Physical Examination

Age group

Associated comorbidity

Associated activity

Acuity of presentation

Differential Diagnoses

Laboratory Studies

Imaging Studies

Procedures

Histologic Findings

Staging

Treatment Paradigm

by Stage

by Modality

Chemotherapy

Radiation Therapy

Surgical Interventions

Hormone Therapy

Immunotherapy

Hyperthermia

Photodynamic Therapy

Stem Cell Transplant

Targeted Therapy

Palliative Care

Medication

Media Gallary

References

https://www.ncbi.nlm.nih.gov/books/NBK560929/

Hypereosinophilic syndrome

Updated : February 14, 2024




Blood granulocytes called “eosinophils” produce cytoplasmic granules that bond with acidic dyes like “eosin” and possess basic proteins. They are derived from bone marrow, and GM-CSF, IL-5, and IL-3 promote their synthesis. They circulate for 4.5 to 8 hours at a time. They can stay in tissues for eight to twelve days, especially in the digestive and respiratory tracts.

Below 5 percent of circulating leukocytes are eosinophils. A rise in the number of circulating eosinophils above 500/mm3 is known as eosinophilia. Eosinophilia can be classified as mild (500 to 1500/mm3), medium (150 to 5000/mm3), or serious (>5000/mm3), depending on the values.

Absolute eosinophil levels of more than 1500/mm3 on two separate occasions, at least a month apart, or demonstrable tissue eosinophilia are both considered to be symptoms of hypereosinophilic syndrome.

Eosinophilia frequency and incidence are not well understood. Eosinophilia is not preferential for any one sex. Depending on the reason, there might be geographic implications, though. Tropical nations are more likely to experience parasite infestations.

In affluent nations, allergic diseases are quite frequent. The diagnosis of idiopathic hypereosinophilia is generally made between the ages of 20 and 50, while it has been known to occur at extreme ages at both extremes of the curve.

Eosinophils differentiate in the bone marrow, where they also stop developing further after leaving. They live primarily outside of the vasculature in tissues. Eosinophils are drawn into the affected tissues in eosinophil-related diseases. Eosinophilopoiesis and eosinophil stimulation are brought on by IL-5 synthesis and immunological responses mediated by T helper-2 cells.

IL-5 is a key cytokine involved in eosinophil generation and activation. When eosinophils are activated, they degranulate and then discharge cationic proteins into the site tissues via which they work.

The host wall may also sustain harm from these liberated proteins, which may also be proteolytic enzymes. In order to maintain homeostasis and regulate the immune system, eosinophils also release cytokines, including IL-10 as well as IL-14.

Primary and secondary eosinophilia is also possible:

Primary factors:

  • CEL – chronic eosinophilic leukemia
  • PDGFRA, PDGF-AB, and FGFR1 gene rearrangements in lymphoid and myeloid cancers
  • Eosinophilia hereditary
  • Hypereosinophilic syndrome without a known cause

Secondary Factors:

  • Ancylostomiasis, cysticercosis, ascariasis, hydatid cyst (echinococcosis), strongyloidiasis, schistosomiasis, toxocariasis (visceral larva migrans), and trichinellosis are some examples of parasite infestations.
  • Bacterial and fungal infections: scarlet fever, occasionally chronic tuberculosis, disseminated histoplasmosis, coccidioidomycosis, and bronchopulmonary aspergillosis.
  • Allergic diseases: hay fever, bronchial asthma, Stevens-Johnson condition, DRESS syndrome, food, and allergy to drugs.
  • Skin disorders: Atopic dermatitis, Mycosis fungoides, eczema, Sezary syndrome, pemphigus.
  • Host versus graft reaction
  • Chrug-Strauss syndrome and eosinophilic myalgia syndrome are examples of connective tissue illness.
  • Other: eosinophilic gastroenteritis, pancreatitis, reactive pulmonary eosinophilia, and tropical eosinophilia.

Depending on a number of variables, including eosinophilia’s underlying etiology, the existence of organ damage, its subtype, and the timing of intervention, the prognosis might range from a minor illness to a catastrophic consequence.

https://www.ncbi.nlm.nih.gov/books/NBK560929/