Idiopathic hypereosinophilic syndrome (IHES) is a leukoproliferative disorder and refers to a situation when there is an unexplained prolonged eosinophilia with associated organ system dysfunction. The condition can affect several organ systems which includes:
- heart: cardiac involvement in idiopathic hypereosinophilic syndrome
lung: pulmonary involvement in idiopathic hypereosinophilic syndrome
- can occur in up to 40% of cases 7.9
- pulmonary manifestations are sometimes categorised under the spectrum of eosinophilic lung disease 9
- central nervous system5: CNS involvement in idiopathic hypereosinophilic syndrome
- peripheral nervous system: peripheral nervous system involvement in idiopathic hypereosinophilic syndrome
- eyes: ocular involvement in idiopathic hypereosinophilic syndrome
- joints: rarely seen rheumatological manifastations of idiopathic hypereosinophilic syndrome
Individuals have prolonged raised total leukocyte counts with raised eosinophil counts. Usually the total leukocyte counts are less than 25,000/μL with 30-70% comprising of eosinophils. At times extremely high leukocyte counts (>90,000/μL) can also develop which can then result in a poorer prognosis.
Radiographic features are probably best discussed under individual categories.
History and etymology
It was first described by W R Hardy and R E Anderson in 1968 4.
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