Endogenous interleukin-11 (IL-11) levels in newly diagnosed children with acquired severe aplastic anemia (SAA)

BACKGROUND: Impaired hematopoietic growth factor production is a hypothetical contributing factor to the development of acquired severe aplastic anemia (SAA). The serum levels of most hematopoietic cytokines in SAA patients are elevated. OBJECTIVE: To measure interleukin-11 levels in newly diagnosed SAA children and attempt to correlate levels with disease severity and response to therapy. DESIGN/METHODS: Following enrollment into a clinical study but prior to treatment, serum samples were obtained from 11 newly diagnosed children with acquired SAA. These samples were collected between May 2000 and September 2002. IL-11 levels were quantified utilizing an ELISA technique. RESULTS: Ten of the 11 patients had low or normal levels of IL-11 (<85 pg/mL) and one had an elevated level of 409 pg/mL (normal range 15-200 pg/mL). CONCLUSIONS: The production of IL-11 does not increase in response to thrombocytopenia in most children with SAA. The significance of this laboratory observation is not clear at this time. Further studies are warranted to determine what, if any, role this plays in the development of this disorder and if the administration of recombinant human IL-11 might be beneficial in the treatment of acquired SAA.