Incidence of sepsis after peripheral blood progenitor cells transplantation: analysis of 86 consecutive hemato oncological patients.

The incidence of documented infections after autologous peripheral blood progenitor cells transplantation (PBPCT) was retrospectively evaluated in 86 consecutive patients (47 males 39 females; median age 36 years, range, 18-63) treated in our institution; 83 patients had refractory hematological malignancies (40 non-Hodgkin's lymphoma, 19 Hodgkin's disease, 17 multiple myeloma, 7 acute myeloblastic leukemia) and 3 had solid tumors (1 rabdomyosarcoma, 1 neuroblastoma, 1 osteosarcoma). All patients developed fever after transplantation lasting a median of 2 days (range 1-17); 20 instances of documented sepsis developed in 17 patients (19.7%). Gram positive microorganisms were implicated in all but 4 cases. There were no fatalities directly due to infections and no correlation was found between the risk of infection and reaching PMN > 0, 1 x 10(9)/L, PMN > 0.5 x 10(9)/L. In addition no specific risk factors related to age, disease, conditioning regimen, use of central venous catheter (CVC), type of transplant, and isolation measures were identified.

RhG-CSF-mobilized CD34+ peripheral blood progenitors are myeloperoxidase-negative and noncycling irrespective of CD33 or CD13 coexpression.

Cycling status, myeloperoxidase expression, informative surface markers, and proliferative potential of peripheral blood hemopoietic progenitors (PBHP) were evaluated by flow cytometry in 10 patients affected by resistant lymphoma, and submitted to stem cell mobilization with combination chemotherapy (MiCMA) followed by recombinant human granulocyte colony-stimulating factor (rhG-CSF, 5 micrograms/kg/day). CD34+ PBHP coexpressed myeloid-associated and activation antigens, i.e., CD33 (96%, range 85-99), CD13 (99.5%, range 99.4-99.8), HLA-DR (99%, range 96.5-99.8), and CD38 (98%, range 90-100), lacked intracytoplasmic myeloperoxidase (MPO, < 3%), and resided in the Gzero/G1 phase of the cell cycle (96.5%, range 81-99.5, compared with 70%, range 49-78 bone marrow HP; p = 0.0007), independently of surface membrane phenotype; S-phase percentages of sorted CD34+ CD33(+)/-, CD34+CD38(+)/-, CD34+HLA-DR(+)/-, CD34+CD45RA(+)/-, CD34+CD45RO(+)/-, and CD34+CD41a(+)/- subpopulations were always negligible. In colony assays, 5-week-old long-term cultures seeded with CD34+CD33- cells yielded as many colonies as did CD34+CD33+ cells. In conclusion, rhG-CSF-mobilized CD34+ PBHPs contain noncycling, highly immature progenitors in which the expression of myeloid-associated antigens, i.e., CD33 or CD13, might not be indicative of myeloid commitment.

Plasmodium vivax malaria after autologous bone marrow transplantation: an unusual complication.

We report the case of unusually early infection by Plasmodium vivax after autologous bone marrow transplantation in a 20-year-old female from Bangladesh affected by acute myelogenous leukemia in first complete remission (CR) who underwent autologous bone marrow transplantation in our center. During the aplastic phase she became febrile; broad spectrum antibiotics and antifungal therapy were without effect. Blood smears were examined and Plasmodium vivax was detected despite a very low number of red cells infected. Cloroquine therapy for 3 days was given followed by primaquine for 2 weeks in order to avoid possible cloroquine resistance. Fever disappeared within 48 h from initial treatment and the patient was discharged having completely recovered at day +30. Primary malaria infection in non-endemic areas is a very rare event. In this particular case, after excluding primary infection or blood transfusion-mediated infection, malaria was attributed to a recrudescence of a primary unidentified infection.

Extramedullary relapse after allogeneic bone marrow transplantation plus buffy-coat in two high risk patients.

In order to obtain an additional graft versus leukemia effect (GVL) and rapid engraftment, donor leukocyte infusion (DLI) was added to unseparated, sex-mismatched allogeneic bone marrow transplantation in two male patients (age 21, 26) affected by high risk hematological malignancies (refractory T-ALL, refractory B-LBL in leukemic phase). Graft versus host disease (GVHD) prophylaxis consisted of methotrexate (MTX) alone. DLI were obtained after G-CSF 16 ug/kg/day sc. A total of 2.36 and 5.8 x 10(6)/kg MNC, 5.4 and 11 x 10(6)/kg CD34+ cells, 1.3 and 1.3 x 10(6)/kg CD3+ lymphocytes, respectively, were infused. Hemopoietic recovery occurred promptly. Complete chimerism was detected by cytogenetic examination. One patient developed an extramedullary relapse that first involved the cranial nerves, and then the testes, soft tissue and skin; the other patient developed central nervous system disease and then bilateral paravertebral masses with progressive paraplegia. Despite complete medullary remission with normal female karyotype, both patients died from extramedullary progression of their disease. Our observation shows that, at least in high risk patients, no additional GVHD or GVL effect was evident after donor leukocyte infusion. Extramedullary relapse was not prevented despite good control of medullary disease.

Simultaneous measurement of reticulocyte and red blood cell indices in healthy subjects and patients with microcytic and macrocytic anemia.

Using the new Bayer H*3 hematology analyzer (Leverkusen, Germany), we have determined red blood cell and reticulocyte indices in 64 healthy subjects, in patients with microcytosis due to iron deficiency (58 patients) and heterozygous beta-thalassemia (40 patients), and in patients with macrocytosis (28 patients). We found in all cases that reticulocytes were larger than mature red cells by 24% to 35%, with a hemoglobin concentration 16% to 25% lower and a similar hemoglobin content. The correlation between red cell and reticulocyte indices was strikingly tight (r = .928 for volume, r = .929 for hemoglobin concentration, r = .972 for hemoglobin content) in all four groups, regardless of red blood cell size. The ratio of reticulocyte to red blood cell mean corpuscolar volume (MCV ratio) was constantly above 1. Inversion of the MCV ratio was observed only in four patients. It was always abrupt and transitory and was associated with erythropoietic changes leading to the production of red blood cells of a different volume (treatment of megaloblastic anemia, functional iron deficiency, bone marrow transplantation). In two cases of marrow transplantation, reticulocyte volume fell during the aplastic phase after conditioning chemotherapy and then rapidly increased up to values higher than before; this production of macroreticulocytes was the earliest sign of engraftment.