Long-term Use of Anagrelid in Essential Thrombocythemia Treatment of a Child Under 12 Months

Abstract 5072

Essential thrombocythemia (ET) is currently classified as a chronic myeloproliferative disorder. Anagrelide is a novel platelet lowering agent that has recently been approved for use n ET.

We present the case of ET in an 8 –month- old girl, who was treated with Anagrelid for 13 months.

The girl was admitted to hospital because of elevated platelet count. She had stomach pains periodically. On admission the child's condition was good but on palpation her stomach was sore and her spleen was enlarged. Laboratory investigations showed an elevated platelet count (1. 5m) and hypercalemia (6. 3mEq/l). Thrombopoetin was normal.

Acesan was added to the treatment. A morphology performed after 1 month revealed further elevation of platelets (up to 2. 65m). On the basis of laboratory investigations, bone-marrow biopsy and trepanobiopsy, we eliminated an oncological disease and infectious diseases of connective tissues.

On bone-marrow investigation, acquired mutation of JAK2 (V617F) tyrosine kinase was diagnosed, which confirmed ET.

On account of the growing number of platelets, which was life - threatening, we decided to administer anagrelid, starting with a dose of 0. 25 mg per day. The number of platelets decreased to 1. 4m, so the dose was increased to 0. 25 mg twice daily after 3 weeks.

At present, after 37 months of anagrelide treatment, the number of platelets in the child ranges between 400 and 650.

The patient visits our, department for monthly check-up (morphology, biochemical tests, ECG and echocardiography).

In international literature there is no information on the use of Anagrelid in ET treatment of children under 12 months old. However, on the basis of our observations and initial results of treatment, it seems that the above protocol for Anagrelid administration is safe for infants of this age.