Thank you for your inquiry.
Pediatric hypereosinophilic syndrome is rare and you certainly have enough other causes of eosinophilia to explain the elevated eosinophil count in your patient. In addition, the recent eosinophil count of 1,136 would be inconsistent with a diagnosis of hypereosinophilic syndrome in which the counts are above 1,500. In addition, you would not expect the count to go down with the treatment that you instituted if your patient had hypereosinophilic syndrome. For these reasons, in my opinion, the eosinophilia in your patient is not due to hypereosinophilic syndrome. Therefore, I would have little concern about simply following her with appropriate treatment for her allergic disease.
Having said this, there may be disagreement regarding this opinion, and therefore if you do decide to pursue a diagnosis of hypereosinophilic syndrome, the link to an excellent reference online copied below, plus the two references copied below will be excellent resources for you in terms of what workup might be indicated. In addition, we have several entries on our Ask the Expert website which have discussed the issue of the evaluation of an elevated eosinophil count.
Thank you again for your inquiry and we hope this response is helpful to you.
Pediatric Hypereosinophilic Syndrome Workup
M. van Grotela, M. de Hoogb, R.R. de Krijger c, H.B. Beverlood, M.M. van den Heuvel-Eibrinka Hypereosinophilic syndrome in children
Leukemia Research 36 (2012) 1249– 1254
Recently, according to the Hypereosinophilic Diseases Working Group of the International Eosinophil Society, six variants of hypereosinophilic syndrome have been proposed, i.e. (1) myeloproliferative, (2)lymphoproliferative, (3) idiopathic/undefined, (4) overlapping, (5) associated and (6) familial variant.Hypereosinophilic syndrome is a rare disorder in children and can occur at any age during childhood. Corticosteroids are the treatment of choice, whereas other treatment options are hydroxyurea, IFN, imatinib, vincristine, mepolizumab. We present a fulminant fatal case of hypereosinophilic syndrome in a teenager with an initial presentation of an idiopathic thrombocytopenia (ITP) and present a narrative review of literature.
Indian J Pediatr. 2013 Feb;80(2):124-7. doi: 10.1007/s12098-012-0821-x. Epub 2012 Jun 28.
Idiopathic hypereosinophilic syndrome in children: 3 cases with review of literature.
Kanthila J, Bhaskaranand N.
Department of Pediatrics, Kasturba Medical College, A-14, A Block, KMC Staff Quarters, Light House Hill Road, Mangalore, 575003, India.
Objectives: To highlight the varied clinical manifestations and management of idiopathic hypereosinophilic syndrome, a rare disorder in children.
Methods: Retrospective review of case records of 3 patients who were diagnosed to have idiopathic hypereosinophilic syndrome (IHES) in a tertiary referral centre between 1997 and 2010 was performed. These 3 children presented with different symptoms and the first case had cardiac involvement. All had very high absolute eosinophil count (cells/mm(3)) 43,206, 9,082, 2,925, respectively. Diagnosis was confirmed by bone marrow biopsy in all three cases and supported by liver biopsy in the first two cases and inguinal lymphnode biopsy in the last case. All 3 children responded to treatment with steroids, with only second patient requiring hydroxyurea to control disease.
Results: Case 1 and 2 are on follow up for 13 y and 10 y respectively and both are asymptomatic. Case 3 expired due to sepsis 1 mo after diagnosis.
Conclusions: Treatment with steroids with or without hydroxyurea gave good response in all 3 cases. Hence, they still remain the gold standard for the treatment of IHES in children.
Phil Lieberman, M.D.