VPB0283 - Deep venous thrombosis in a child with Down syndrome as a presenting manifestation of acute lymphoblastic leukemia

Background: Venous thrombosis is a well-recognized and serious complication of acute lymphoblastic leukemia (ALL) in childhood. The etiology is multifactorial and may include inherited thrombophilia risk factors, hypercoagulability resulting from the leukemia itself, the presence of central venous line and the contribution of chemotherapy.

Aims: This case report aims to describe the clinical course and management of deep venous thrombosis as a presenting manifestation of ALL in a 5-year-old boy with Down syndrome.

Methods: case report

Results: A 5-year old boy with Down syndrome presented with one-day history of left leg pain, swelling in the thigh and calf and refusal of walking. Complete blood count on admission was normal. His coagulation studies revealed a shortened APTT (22.2 seconds) and high levels of D-dimer (9077 ng/ml). Doppler ultrasound exam of lower extremity showed occlusive thrombus in the left common femoral and popliteal vein. Anticoagulant therapy with low-molecular-weight heparin (LMWH) was initiated. After 3 weeks at the follow-up examination it was observed signs of complete recanalization of the popliteal vein. Common femoral vein was still thrombosed and incompressible. Over the following days his condition has worsened experiencing fever, irritability, lower back and legs pain. Blood counts showed mild anemia and thrombocytopenia. Bone marrow aspiration revealed precursor – B cell ALL. Induction chemotherapy was started according to the ALL IC BFM 2002 along with concomitant application of LMWH. Complete remission on day 33 was achieved and thrombosis was resolved. The patient continued the protocol along with concurrent LMWH prophylaxis and the outcome was favorable without clinical symptoms or signs related to recurrent thrombosis. Thrombophilia screening showed heterozygous mutation for Factor II, MTHFR C677T, MTHFR A1298C and B-Fibrinogen.

Conclusion(s): Thrombosis may be a presenting feature of childhood ALL. Prompt anticoagulation with LMWH is mandatory to prevent extension or recurrence of VTE and save in the setting of ALL treatment.