EOSINOPHILS LEAD THE WAY

TOPIC: Lung Pathology TYPE: Medical Student/Resident Case Reports INTRODUCTION: Hypereosinophilic Syndrome (HES) is a rare condition characterized by sustained eosinophil counts greater than 1.5x103/uL with pathologic confirmation of tissue hypereosinophilia (HE). It usually affects multiple organs in the absence of clonal or other secondary causes of eosinophilia. The most common organs affected are the lungs, skin, heart, gastrointestinal tract, and brain. CASE PRESENTATION: This is an 81-year-old male patient with history of alcohol abuse, hypertension, and atrial fibrillation, who presented with diffuse skin itching and burning sensation for three days after working with polyvinyl chloride (PVC) tubing material. He referred having associated generalized weakness, anorexia, and dry cough. Labs were remarkable for having eosinophilia of 17x10^3/uL, mild transaminitis (SGPT:54 U/L, SGOT:45 U/L), elevated high sensitive troponins of 41-43 without delta and worsening renal function with serum creatinine increasing from 0.9 to 1.9 mg/dL. Immunoglobulin E was found to be elevated in 774.8, however Strongyloides IgG antibody and Schistosoma antibody were negative, ruling out endemic parasite involvement. Chest CT scan without contrast revealed moderate centrilobular emphysema, mild areas of ground glass opacities and tree-in-bud opacities bilaterally, for which it was decided to undergo bronchoscopy examination to exclude other etiologies, including malignancy or pneumoconiosis. This procedure revealed no lesions or masses, with bronchoalveolar lavage reporting no malignant cells, as well as negative acid-fast bacilli or fungal organisms. To rule out myelodysplastic syndrome a bone marrow biopsy was performed revealing hypercellular marrow with 48 percent of eosinophils, however flow cytometry showed no clonal cells or blasts, as well as negative BCL/ABL and PDGFR alpha. These findings were consistent with Idiopathic Hypereosinophilic Syndrome, for which he was started on prednisone 40 mg PO daily. DISCUSSION: HE can be confirmed by bone marrow biopsy of more than 20 percent of eosinophils. Most of these patients tolerate and respond well to glucocorticoid therapy, however in refractory cases the tyrosine kinase inhibitor imatinib has shown to improve the patient's outcome. CONCLUSIONS: It is essential to rule out secondary causes of hypereosinophilia, which may be seen in parasitic infections, pneumoconiosis, or malignancy, to prevent delay in diagnosis and prompt adequate therapy. REFERENCE #1: Roufosse, F.E., et al. Hypereosinophilic syndromes. Orphanet J Rare Dis 2, 37 (2007) DISCLOSURES: No relevant relationships by Christina Arraut-Hernandez, source=Web Response No relevant relationships by Jose Gutierrez-Nunez, source=Web Response No relevant relationships by Francisco Tirado-Polo, source=Web Response