Catastrophic thrombosis in idiopathic hypereosinophilic syndrome

Abstract

A 43-year-old female was admitted with shortness of breath, chest pain and digital ischaemia. On examination she was hypotensive, tachycardiac and tachypnoeic and had a tender epigastrium and swollen tender left lower leg. A full blood count showed a white cell count of 21·2 × 109/l with 22% eosinophils (absolute eosinophil count 4·6 × 109/l) and a platelet count of 14 × 109/l. Liver function tests were abnormal with an alkaline phosphatase of 393 iu/l, alanine transaminase of 498 iu/l and a lactate dehydrogenase level of 2497 iu/l. D-dimer and troponin T were markedly elevated at 26 630/l and 7·26 μg/l, respectively. Clotting studies, including a Clauss fibrinogen, were normal apart from a prolonged prothrombin time of 17 s. The blood film was leucoerythroblastic with a marked eosinophilia. Eosinophil morphology was normal. A Doppler ultrasound of the lower limbs demonstrated bilateral deep vein thromboses from the superficial femoral vein to the tibial veins. Computed tomography (CT) pulmonary angiography showed bilateral extensive pulmonary emboli with a saddle embolus in the main pulmonary artery (left). A CT scan of the abdomen and pelvis demonstrated a thrombus in the suprahepatic inferior vena cava (right, white arrow) extending into the right atrium and across the tricuspid valve. Hepatomegaly with right hepatic and portal vein occlusion with thrombus (right, black arrows) were also noted. A full work up for parasitic, malignant and rheumatological diseases was negative. JAK2 V617F, BCR-ABL1 and FIP1L1-PDGFRA were negative by polymerase chain reaction. There was no evidence of a B- or T-cell clone by peripheral blood B- and T-cell receptor rearrangement analysis. A full thrombophilia screen was negative. Bone marrow aspirate and trephine biopsy sections were hypercellular with a marked eosinophilia. There was no increase in mast cells. Cytogenetic analysis and flow cytometry on the bone marrow aspirate were normal. Platelet transfusions were given and the patient was commenced on an unfractionated heparin infusion. She was then transferred to the nearest cardiothoracic unit where she underwent inferior vena cava filter insertion and thrombolysis. She was commenced on prednisolone 1 mg/kg per d for 2 weeks, which was then tapered over the next 8 weeks. The patient was successfully warfarinized and remains thrombus-free, on anticoagulation, 3 years later. Her full blood count and liver function tests are normal apart from an eosinophil count of 0·5 × 109/l. She has not required retreatment with prednisolone. This case illustrates multiple life-threatening simultaneous thromboses in association with hypereosinophilic syndrome (HES) and disseminated intravascular coagulation. Physicians should be aware of the thromboembolic complications of HES. About 25% of patients develop thromboembolism and 5–10% die as a result. The underlying mechanism of thrombosis is not fully understood but at least four granule proteins released by eosinophils are thought to cause hypercoagulability.