When to harvest peripheral-blood stem cells after mobilization therapy: prediction of CD34-positive cell yield by preceding day CD34-positive concentration in peripheral blood.

PURPOSE: To evaluate whether the CD34+ yield from a single peripheral-blood stem-cell (PBSC) harvest could be predicted by measurement of the patient's circulating WBC and CD34+ cell concentrations on the day before harvest. PATIENTS AND METHODS: Thirty-nine patients with hematologic or nonhematologic malignancy underwent 41 stem-cell mobilization episodes with cytotoxic chemotherapy and/or granulocyte colony-stimulating factor (G-CSF), and a total of 63 leukapheresis procedures were performed. Peripheral-blood samples were analyzed for WBC and CD34+ cell concentration both on the day before and the day of leukapheresis. RESULTS: The median WBC and CD34+ concentrations on the day preceding leukapheresis were 10.0 x 10(9)/L (range, 0.4 to 44.4) and 24.9 x 10(6)/L (range, 0.1 to 349.4), respectively. On the day of harvest, the corresponding figures were 15.1 x 10(9)/L (range, 1.5 to 52.6) and 29.3 x 10(6)/L (range, 0.1 to 543.1), respectively. The median CD34+ cell number collected in a single leukapheresis was 2.6 x 10(6)/kg body weight (range, 0.1 to 26.1). Both the preceding day (r = .84, P < .001) and harvest day (r = .95, P < .001) CD34+ circulating concentrations correlated significantly with the number of CD34+ cells per kilogram collected at leukapheresis. The correlation between CD34+ cells per kilogram collected and harvest day WBC count was also significant (r = .43, P <.001), but with the preceding day WBC count was nonsignificant. CONCLUSION: The number of CD34+ cells harvested in a single leukapheresis can be predicted by measurement of the preceding day peripheral-blood circulating CD34+ concentration, and on the basis of these data a table of probable CD34+ cell yield has been constructed. This correlation may facilitate the efficient organization of leukapheresis procedures.

Severe rotavirus-associated diarrhoea following bone marrow transplantation: treatment with oral immunoglobulin.

Two patients developed acute severe rotavirus-associated diarrhoea following BMT. Both received treatment with oral immunoglobulin and in each case the diarrhoea substantially resolved within 3 days, and rotavirus became undetectable in their stool. Oral immunoglobulin may be a useful therapy for rotavirus gastroenteritis post-BMT.

Poor prognosis acute myeloid leukaemia treated by matched unrelated donor marrow transplant without preceding total body irradiation.

Two patients with acute myeloid leukaemia, one in relapse after autologous bone marrow transplantation (BMT) (aged 52 years) and the other with primary resistant disease secondary to previously treated malignancy, have received marrow transplants from matched unrelated donors. Cytoreductive conditioning in both cases was with high-dose combination chemotherapy alone. Engraftment was aided by the administration of total lymphoid irradiation together with in vivo antilymphocyte antibody prior to marrow infusion. Both patients survive in complete remission, currently at 12 and 15 months post-BMT respectively. The avoidance of total body irradiation in BMT patients at high risk of early treatment-related mortality may be advantageous.

Rapid Remission Induction and Improved Disease Free Survival in Acute Myeloid Leukaemia Using Daunorubicin, ARA-C, and CCNU.

Thirty-four patients with acute myeloblastic leukaemia were treated with DAC, a schedule containing the nitrosourea CCNU (lomustine) 200 mg/m2 given on day one of treatment, together with a standard "3 + 7" remission induction schedule of daunorubicin (DR) and cytosine arabinoside (Ara-C). The results were compared with an historical control group of 24 patients who received 3 + 7 remission induction (DA). The DAC patients were older (median age 55 years) compared with the DA patients (median age 42 years), and had a higher frequency of poor prognosis features including secondary AML and prior myelodysplasia (11/34 DAC patients versus 1/24 patients receiving DA). Overall remission induction was the same for both groups (79%), but 89% of DAC patients who achieved remission did so with one course, compared with 37% of DA patients. The cytopenic phase following a single course of DAC was only slightly longer than that of a single course of DA (26 days vs. 19.5 days). DAC also gave a higher three year actuarial survival than DA (34% vs. 11%), and a lower relapse probability (44% vs. 74%). These results support the hypothesis that chemotherapy for AML may be favoured by including agents such as CCNU, which are active against both non-cycling and cycling leukaemic stem cells, in remission induction schedules.

Determination of 5-aminolaevulinic acid and porphobilinogen by high-performance liquid chromatography.

A strong anion-exchange column coupled to a strong cation-exchange column with acetate buffer as eluent or reversed-phase ion-pair chromatography on octadecylsilica with methanol-water containing 1-heptanesulphonic acid as the mobile phase is described for the simultaneous separation of 5-aminolaevulinic acid and porphobilinogen. The separation is applied to the development of a fast and simple method for determining the activity of the enzyme aminolaevulinic acid dehydrase in human erythrocytes. 5-Aminolaevulinic acid is used as the enzyme substrate and the enzyme activity is expressed as micromoles of porphobilinogen formed per ml of erythrocytes in 1 h at 38 degrees. 5-Aminolaevulinic acid and porphobilinogen can also be separated from the urine of prophyric patients but the UV detector has insufficient sensitivity for the determination of 5-aminolaevulinic acid.