Recombinant interleukin-6 in the treatment of congenital thrombocytopenia associated with absent radii.

PURPOSE: The role interleukin-6 (IL-6) in the treatment of congenital thrombocytopenias is unknown. The purpose of this case report is to describe the efficacy of IL-6 in a child with thrombocytopenia with absent radii (TAR) syndrome.

METHODS

A 23-month-old girl with TAR syndrome was treated with recombinant IL-6 (Sigosix; Serono Laboratories, Norwell, MA) at a dose of 7 micrograms/kg subcutaneously daily. Complete blood counts were monitored weekly. The child was closely monitored for any toxicity.

RESULTS

After 3 weeks of therapy, the patient had an increase in platelet count from a baseline of 5,000 to 8,000/microliter to a maximal level of 33,000/microliter. She was platelet transfusion-independent during IL-6 therapy. Fevers and chills, the main toxicities encountered, were controlled with acetaminophen and ibuprofen. An increase in the IL-6 dose caused anemia with no further increase in platelet count. After discontinuation of the drug, her hemoglobin rose to baseline and the platelet count returned to pretreatment levels.

CONCLUSIONS

We conclude that IL-6 may benefit some children with TAR syndrome. The role of IL-6 and other thrombopoietic agents in the treatment of TAR and other congenital thrombocytopenias deserves further clinical study.