Treatment of Red Cell Hypoplasia Following Fully Ablative Matched Related Allogeneic Transplant with Stem Cell Boost.

Abstract 4530

We present the case of a 34 year old African American male with T-cell non-Hodgkin's Lymphoma who received a matched related allogeneic transplant using a preparative regimen of cyclophosphamide and TBI from his brother on 11/4/09. The patient's blood type was O+ and the donor's blood type was B+. The cell dose was 10.3 × 10⁶ CD34/kg. His post transplant course was generally uncomplicated. Although he recovered his ANC on D+18 and he was platelet transfusion independent by D+28, he never became red cell transfusion independent. A bone marrow biopsy on day 33 showed no evidence of disease with minimal erythroid recovery. His engraftment studies were all 100% donor cells. His reticulocyte counts are detailed in the table below. On day 126 he had a positive qualitative PCR for parvovirus. He received IVIG (400 mg/kg) for 5 consecutive days beginning 3/15/10. Weekly surveillance for CMV by PCR remained non-detectable.

Repeat bone marrow biopsies on day 63 and 88 continued to show neutrophil engraftment, hypoplastic megakaryocytes and aplasia of red cells. His immune suppression was discontinued on day 99. A fourth bone marrow biopsy on day 155 again showed erythroid hypoplasia with neutrophil and megakaryocyte hypoplasia.

He received a second infusion of PBSC without a conditioning regimen. He received 2.5 × 10⁶ G-CSF mobilized HPC-A from the original donor on day 205 post transplant. Tacrolimus was reinitiated on day 203. As noted in the table below, his reticulocyte count normalized three weeks post infusion. His last RBC transfusion was given two days prior to the stem cell infusion and he remains transfusion independent today. He continues on tapering doses of tacrolimus and has not experienced any graft versus disease.