Effect of granulocyte-colony stimulating factor on empiric therapy with flomoxef sodium and tobramycin in febrile neutropenic patients with hematological malignancies. Kan-etsu Hematological Disease and Infection Study Group

The clinical effects of concomitant use of granulocyte-colony stimulating factor (G-CSF) on empiric antibiotic therapy in febrile neutropenic patients were evaluated in a randomized fashion. Two hundred and fourteen neutropenic febrile episodes (neutrophil counts < 1.0 x 10(9)/l) were treated with flomoxef sodium and tobramycin with or without G-CSF. The resolution of fever at day 4 (excellent response) or at day 7 (good response) was deemed effective. Among 157 evaluable episodes, the observed excellent responses were 31 (38.8%) and the good responses were 20 (25.0%) in the G-CSF group; those in the control group were 26 (33.8%) and 25 (32.5%), respectively. The overall efficacy rate was 63.8% (51/80) in the G-CSF group and 66.2% (51/77) in the control group (not significant). The initial neutrophil count was 0.186 +/- 0.249 x 10(9)/l in the G-CSF group and 0.235 +/- 0.290 x 10(9)/l in the control group, and rose to 2.889 +/- 4.198 x 10(9)/l and 0.522 +/- 0.844 x 10(9)/l, respectively, at day 7. These results indicate that G-CSF does not affect the rate of response to empiric antibiotic therapy in febrile neutropenic patients, although a significant effect of G-CSF was observed on neutrophil recovery.     

Serum concentrations of granulocyte colony-stimulating factor (G-CSF) in antithyroid drug-induced agranulocytosis

Granulocyte colony-stimulating factor (G-CSF) levels in serum were determined by a highly-sensitive chemiluminescent enzyme immunoassay (limit of detection, 0.5 pg/ml) in 54 patients with Graves' disease including 6 patients complicated with methimazole-induced agranulocytosis. Serum G-CSF levels in patients with Graves' disease were not different from normal subjects and did not correlate with serum FT4 level or circulating neutrophil counts. Before the onset of agranulocytosis, there was no difference in serum G-CSF level between the patients complicated with agranulocytosis and the uncomplicated patients. When circulating neutrophil counts decreased to less than 0.5 x 10(9)/L, serum G-CSF level elevated with the mean of 106.8 +/- 82.2 (SD) pg/ml, but the level did not correlate with the duration of agranulocytosis. Interestingly, maximum serum G-CSF level during the treatment with recombinant human G-CSF (100 microg/day) was related to bone marrow finding at the onset of agranulocytosis and correlated with the duration of agranulocytosis (r = 0.824, p < 0.05). In conclusion, measuring serum G-CSF levels with a highly-sensitive chemiluminescent enzyme immunoassay revealed that 1) thyrotoxicosis does not affect serum G-CSF level, 2) serum G-CSF level during antithyroid drug treatment does not play an important role in development of agranulocytosis, 3) the maximum serum G-CSF level in the course of agranulocytosis is related to the responsiveness of bone marrow to G-CSF and the recovery time from agranulocytosis.     

COP-BLAM regimen combined with granulocyte colony-stimulating factor and high-grade non-Hodgkin's lymphoma

Abstract: The clinical efficacy of COP-BLAM chemotherapy combined with human recombinant granulocyte colony-stimulating factor (G-CSF) was evaluated in 104 previously untreated patients with non-Hodgkin's lymphoma (NHL). According to the method of Laurence et al., a modified COP-BLAM regimen was administered every 21 days. G-CSF was added when the granulocyte count fell below 1000 × 10⁹/l. Ninety-eight of 104 (94.2%) patients achieved a complete remission; the 4-year survival rate was 82.4% with a median duration of observation of 26 months. Survival was significantly longer in patients with low serum LDH levels, B-cell type or low CRP or in earlier clinical stages, than in patients with high serum LDH levels, T-cell type or higher CRP levels or in advanced clinical stages. The mean duration of administration of G-CSF was 5.4 days. Twelve patients developed infections during treatment. The adverse effects of G-CSF included interstitial pneumonia, bone pain and fever. Patients administered COP-BLAM combined with G-CSF achieved a high rate of remission and had a low incidence of infection. Nearly all the patients could be treated in 21-day cycles. The results suggest that G-CSF combined with COP-BLAM was effective in treating NHL, because the patients can tolerate a higher dose of the anticancer agents.     

Change in serum G-CSF levels in patients with Graves' disease by treatment with methimazole]

We evaluated the determination of serum G-CSF in the diagnosis of granulocytopenia due to methimazole (MMI) in 54 patients with Graves' disease, while they were being treated with MMI, by way of measuring WBC counts and serum levels of G-CSF, thyroid hormones, IgE, and interleukin-2. Serum TSH was measured by immunoradiometric assay, serum G-CSF was done by enzyme immunoassay, thyroid hormones and IgE were done by radioimmunoassay, and serum Interleukin-2 was done by enzyme-linked immunosorbent assay. The population whose G-CSF levels were higher than the minimum detectable level (30pg/ml) was 6 (30%) in normal subjects, 4 (22%) in patients with untreated Graves' disease, 2 (12%) in patients with treated euthyroid Graves' disease, 3 (23%) in patients with Graves' disease who had gone through agranulocytosis, and 2 (33%) in patients with Graves' disease complicated with granulocytopenia. There was no significant change in WBC counts for 4 weeks, but there was a significant difference between WBC counts before treatment and those at 8 weeks after treatment. We observed no significant change of serum G-CSF levels in patients with Graves' disease under treatment. However, there were significantly high levels of serum G-CSF and significantly low counts of WBC in patients with Graves' disease complicated with granulocytopenia induced by MMI, compared with those in normal subjects, patients with untreated Graves' disease, patients with treated euthyroid Graves' disease, and patients with euthyroid Graves' disease who had gone through agranulocytosis.(ABSTRACT TRUNCATED AT 250 WORDS)     

Granulocyte colony-stimulating factor dosing in pegylated interferon alpha-induced neutropenia and its impact on outcome of anti-HCV therapy

Many patients with chronic hepatitis C (HCV) infection undergoing treatment with pegylated interferon-alpha (PEG-IFN-alpha) and ribavirin develop neutropenia requiring dose reduction or granulocyte colony-stimulating factor (G-CSF) supplement. We analysed the database of patients who completed treatment for chronic HCV infection between 2003 and 2006. Patients with absolute neutrophil counts below 1000 cells/microL were initiated on G-CSF (G-CSF group) while a matching group of patients who received anti-HCV treatment without developing neutropenia were used as a control group (non-G-CSF group). Patients on the G-CSF arm were divided into two subgroups based on the timing of G-CSF administration relative to PEG-IFN-alpha administration. Of the 163 patients with HCV infection, 30 patients received G-CSF, most of who were maintained on 300 microg of G-CSF once a week. Administration of G-CSF 2 days before or after each dose of PEG-IFN-alpha did not make a significant difference in the neutrophil counts. In the G-CSF arm, 23 of 30 patients (77%) had undetectable end-of-treatment viral response which was comparable with 27 of 30 in the control group (90%; P = 0.17). There was no statistically significant difference in the sustained viral response between the two groups (61%vs 76%, P = 0.18). In most patients PEG-IFN-alpha induced neutropenia improved with a once-a-week dose of G-CSF with a comparable virological outcome. Timing of G-CSF administration did not make any significant impact on the patient's neutrophil counts but was better tolerated when given 2 days apart from PEG-IFN-alpha.     

Effect of recombinant human GH on circulating granulocyte colony-stimulating factor and neutrophils in patients with adult GH deficiency

BACKGROUND: We previously reported that short-term continuous subcutaneous infusion (CSI) of recombinant human growth hormone (rhGH) increased plasma erythropoietin levels and hemoglobin concentrations in patients with adult GH deficiency. In the present study, we investigated the effect of rhGH on plasma granulocyte colony-stimulating factor (G-CSF) levels and neutrophil counts in patients with adult GH deficiency. METHODS: rhGH was administrated for 1 year in six patients with adult GH deficiency (age range, 24-69 years; mean +/- S.E.M., 51.7 +/- 5.8 years; two males and four females) by means of CSI at a rate of 0.25 U/kg per week. Blood samples were obtained in the morning after overnight fasting every month before and after the start of rhGH administration. Plasma GH, insulin-like growth factor I (IGF-I) and G-CSF levels, and neutrophil counts, were measured. RESULTS: Mean ( +/- S.E.M.) plasma GH levels increased from 0.26 +/- 0.14 to 2.28 +/- 0.20 microg/l 1 month after the start of rhGH administration. An increase of the plasma GH levels was accompanied by an increase in the plasma IGF-I levels from 64.7 +/- 8.5 to 293.3 +/- 80.6 microg/l. Plasma G-CSF levels increased at 2, 3, 8, 9 and 10 months after the start of rhGH administration compared with 28.6 +/- 11.0 ng/l at time 0. The neutrophil counts increased at 2, 3, 7, 8, 9, 11 and 12 months after the start of rhGH administration compared with 2822 +/- 377 neutrophils/microl at time 0. CONCLUSION: rhGH administration increased plasma G-CSF levels and neutrophil counts. GH and/or IGF-I might stimulate neutrophil production and/or release via G-CSF.     

Rapid leukaemic evolution in a cutaneous blastic NK-celllymphoma initially diagnosed as pseudolymphoma

This study was aimed to evaluate the efficacy of G-CSF (Granulocyte colony stimulating factor) administration to 37 patients with neutropenia following intensive combination chemotherapy. The patients were divided into two subgroups including solid tumors given ifosfamide and etoposide combination chemotherapy (IMET subgroup) and acute myeloid leukemia (AML) patients treated with mitoxantrone and cytarabine. Control group consisted of 31 acute myeloid leukemia patients. G-CSF was started on the first day of absolute neutropenia until the absolute neutrophil count was above 1000/mm³ for two consecutive days. G-CSF was found to be effective for early recovery of neutrophil count. Expected response was achieved within 14 days in 91.5% of the courses with a median of fifth day of G-CSF treatment. In conclusion, this study showed the efficacy of G-CSF in early recovery of neutrophil count without any reduction in the incidence of febrile episodes and documented rates of bacterial and fungal infections in patients with acute myeloid leukemia.     

Maintenance treatment of patients with myelodysplastic syndromes using recombinant human granulocyte colony-stimulating factor.

Myelodysplastic syndromes (MDS) are characterized by chronic refractory cytopenias resulting in increased risk of infection, bleeding, and conversion to acute leukemia. In an effort to improve these cytopenias we have treated 18 patients over a 6- to 8-week period with increasing daily subcutaneous doses of recombinant human granulocyte colony-stimulating factor (G-CSF). Sixteen patients responded with improvement in neutrophil counts. On cessation of treatment these counts returned to baseline values over a 2- to 4-week period. To maintain these improved blood counts 11 patients were treated with G-CSF for more prolonged periods. Ten patients again responded with an increase in total leukocyte counts (1.6- to 6.4-fold) and absolute neutrophil counts (ANC) (3.6- to 16.3-fold), with responses persisting for 3 to 16 months. A significantly decreased risk of developing bacterial infections was noted during periods with ANC greater than 1,500/mm3 as compared with periods of time with ANC less than 1,500/mm3. Two anemic patients had a greater than 20% rise in hematocrit over the study period, and 2 additional patients had a decrease in red blood cell transfusion requirements during G-CSF treatment. Bone marrow myeloid maturation improved in 7 of 9 maintenance phase patients. Three patients progressed to acute myeloid leukemia during treatment. The drug was generally well-tolerated and no severe toxicities were noted. These data demonstrated that G-CSF administered to MDS patients by daily subcutaneous administration was well-tolerated and effective in causing persistent improvement of the neutrophil levels and marrow myeloid maturation. These effects were associated with a decreased risk of infection and, in some patients, with decreased red blood cell transfusion requirements.     

Hematologic effects of recombinant human granulocyte colony-stimulating factor in patients with malignancy

The effect of recombinant human granulocyte colony-stimulating factor (G-CSF) on hematologic parameters was evaluated in a phase I clinical study in 18 patients with advanced malignancy. G-CSF was administered once daily as a 30-minute infusion for 14 days; three patients each were treated at increasing dose levels of 1, 3, 10, 30, and 60 micrograms kg-1 day-1. A transient decrease in neutrophil and monocyte counts was observed immediately after the G-CSF infusion, followed by a dose-dependent increase of up to 15-fold. G-CSF-induced neutrophils exhibited an increased O2- radical production, and serum levels of enzymes related to granulocyte turnover, including lysozyme and elastase, were markedly elevated during therapy. A dose-dependent depression of platelet counts occurred in the second third of the treatment course, followed by a spontaneous recovery despite continuing therapy. G-CSF was well-tolerated; minor to moderate bone pain was the most common side effect. The primary course of the malignant diseases studied was not significantly altered. G-CSF appears to be an appropriate means to selectively increase the number of functionally competent polymorphonuclear phagocytes.     

Therapy for neutropenia in hairy cell leukemia with recombinant human granulocyte colony-stimulating factor

STUDY OBJECTIVE: To determine whether recombinant human granulocyte colony-stimulating factor (G-CSF) is effective in increasing neutrophil counts in patients with hairy cell leukemia and neutropenia. DESIGN: Open label, phase I/II study of G-CSF, given by daily subcutaneous injection for up to 7 weeks. SETTING: Outpatient oncology clinic of a university medical center. PATIENTS: A consecutive sample of four patients with hairy cell leukemia complicated by severe neutropenia. Three patients completed the study; one patient was removed after 2 weeks of therapy. INTERVENTIONS: Granulocyte colony-stimulating factor was given by daily subcutaneous injection. Each patient began therapy with 1 microgram/kg body weight.d; after 1 week the dose was increased to 3 micrograms/kg.d, and 1 week later to 6 micrograms/kg.d. Therapy was continued for 5 to 6 weeks. Patients were taught self-injection, and administered treatment at home. MEASUREMENTS and MAIN RESULTS: In three patients, an increase in absolute neutrophil counts from less than 0.9 X 10(9)/L to greater than 4.0 X 10(9)/L was noted within 2 weeks of beginning G-CSF therapy. In two patients, infections resolved during therapy. One patient developed acute neutrophilic dermatosis (the Sweet syndrome) while receiving 3 micrograms/kg.d of G-CSF, and drug therapy was discontinued. CONCLUSIONS: Granulocyte colony-stimulating factor may increase neutrophil counts within 2 weeks in patients with hairy cell leukemia and neutropenia. This therapy may be a useful adjunct to definitive treatment of hairy cell leukemia with interferon or pentostatin.     

G-CSF in Peg-IFN induced neutropenia in liver transplanted patients with HCV recurrence

AIM: To evaluate the efficacy of granulocyte colony stimulating factors (G-CSF) in liver transplanted patients with hepatitis C (HCV) recurrence and Pegylated-IFN α-2b induced neutropenia, and to evaluate the impact of G-CSF administration on virological response.METHODS: Sixty-eight patients undergoing antiviral treatment for post-liver transplantation (OLT) HCV recurrence were enrolled.All patients developing neutropenia received G-CSF.RESULTS: Twenty three (34%) received G-CSF.Mean neutrophil count at the onset of neutropenia was 700/mmc (range 400-750/mmc); after 1 mo of G-CSF it increased to 1210/mmc (range 300-5590/mmc) ( P < 0.0001).Three patients did not respond to G-CSF.Treatment duration was similar in neutropenic and non-neutropenic patients.No differences in the rate of discontinuation, infections or virological response were observed between the two groups.G-CSF was protective for the onset of de novo autoimmune hepatitis ( P < 0.003).CONCLUSION: G-CSF administration is effective in the case of Peg-IFN induced neutropenia increasing neutrophil count, prolonging treatment and leading to sustained virological response (SVR) rates comparable to non-neutropenic patients.It prevents the occurrence of de novo autoimmune hepatitis.     

Treatment of severe neutropenia due to Felty's syndrome or systemic lupus erythematosus with granulocyte colony-stimulating factor.

OBJECTIVES: To examine the efficacy and safety of recombinant human granulocyte colony-stimulating factor (rhG-CSF) and recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) for the treatment of severe neutropenia due to Felty's syndrome (FS) or systemic lupus erythematosus (SLE). METHODS: Eight patients with absolute neutrophil counts (ANC) below 1,000/microL attributable to FS (n = 4) or SLE (n = 4) were treated with rhG-CSF. The hematologic and clinical response as well as side effects were recorded. In addition, reports on the use of rhG-CSF/rhGM-CSF in FS and SLE retrieved from the English language literature were analyzed. RESULTS: RhG-CSF effectively corrected neutropenia due to FS and SLE in seven of the current eight patients. In 54 of 55 FS and SLE patients retrieved from the literature, G-CSF or GM-CSF, respectively, proved to be effective at elevating the neutrophil count, which was often associated with improvement of infectious complications. The neutrophil count often declined again when growth factor treatment was stopped but generally stabilized at a level that exceeded the pretreatment count. Side effects included rare cases of thrombocytopenia, arthralgias, and development of cutaneous leukocytoclastic vasculitis. Side effects were dose dependent and resolved when treatment was discontinued. One of our own patients and 17 previously reported patients continued to benefit from long-term administration of rhG-CSF over periods of more than 40 months. CONCLUSIONS: RhG-CSF is an effective and generally well-tolerated treatment for neutropenia due to FS or SLE. Exacerbation of the underlying rheumatic condition due to G-CSF appears to be rare if G-CSF is administered at the lowest dose effective at elevating the ANC above 1,000/microL.     

Serum granulocyte colony-stimulating factor levels in healthy volunteers and patients with various disorders as estimated by enzyme immunoassay

In order to better understand the patho-physiologic role of granulocyte colony-stimulating factor (G-CSF), we estimated its serum levels in healthy persons and patients with various disorders, using a newly developed enzyme immunoassay (Motojima et al). In 49 of 56 normal healthy persons (88%), the levels were beneath the sensitivity of the assay (less than 30 pg/mL), while in the remaining seven healthy persons, the levels ranged from 33 to 163 pg/mL. On the other hand, nine of 11 patients (82%) with idiopathic aplastic anemia (AA), one patient with Fanconi's anemia, six of 12 patients (50%) with myelodysplastic syndrome (MDS), five of 12 patients (42%) with acute leukemia without any blast cells in the blood (M4: one, M5: one, L1: one, and L2: two), six of 18 patients (33%) with chronic myeloid leukemia (CML), one of two patients with chronic lymphoid leukemia (CLL), two of four patients with lung cancer, one patient with cyclic neutropenia, two of seven patients with malignant lymphoma, and four patients with acute infection had G-CSF levels ranging from 46 pg/mL to greater than 2,000 pg/mL. Interestingly, a reverse correlation between blood neutrophil count and serum G-CSF level was clearly demonstrated for aplastic anemia (r = -.8169, P less than .01). Moreover, it was found that the G-CSF level rose during the neutropenic phase of cyclic neutropenia and after chemotherapy or bone marrow transplantation (BMT) in three patients with leukemia; also high G-CSF levels were positively correlated to blood neutrophil counts in some cases of infectious disorders and lung cancer. The cellular sources and the mechanisms for production and secretion of circulating G-CSF were not investigated in this study, but the data presented here strongly indicate that G-CSF plays an important role as a circulating neutrophilopoietin.     

Serum concentrations of granulocyte colony-stimulating factor in healthy term and preterm neonates and in those with various diseases including bacterial infections

The neonate is uniquely susceptible to severe and overwhelming bacterial infections. One of the most important deficits in the neonatal host defense system seems to be a quantitative and qualitative deficiency of the myeloid and the phagocytic system. Future optimal therapy of neonatal sepsis may include the use of adjuvant immunologic therapy. Granulocyte colony-stimulating factor (G-CSF) has been shown to induce neutrophilia and to enhance mature effector neutrophil function. To evaluate the role of G-CSF with respect to infection, we examined serum levels of G-CSF in term and preterm neonates, using an enzyme-linked immunosorbent assay method. G-CSF levels in healthy neonates showed peak levels up to 7 hours after birth, followed by an increase in total neutrophil cell (TNC) counts. Both G-CSF levels determined between 4 and 7 hours after birth and peak TNC counts correlated with the gestational age of the neonates. The state of nutrition, maternal treatment with glucocorticoids, maternal infection and hypertension, and the mode of delivery influenced peak G-CSF levels. Neonates with signs of infection between 4 and 7 hours after birth had higher levels of G-CSF than did healthy neonates (1,312 +/- 396 pg/mL v 176 +/- 19 pg/mL). In conclusion, the presented results of serum concentrations of G-CSF in relation to TNC counts and various diseases suggests an important role of G-CSF in the regulation of granulopoiesis during the neonatal period.     

Granulocyte-colony stimulating factor-producing myeloma with clinical manifestations mimicking chronic neutrophilic leukemia

A 68-year-old man was diagnosed as having bronchial asthma in November 1996. He presented with leukocytosis in June 2002. The WBC count was 29,900/microliter with 82% mature neutrophils showing toxic granules. The neutrophil alkaline phosphatase score and serum level of vitamin B12 were elevated. Bone marrow demonstrated myeloid hyperplasia and plasmacytosis. Cytogenetic and molecular analyses were negative for Philadelphia chromosome and BCR/ABL fusion gene. Lambda-type Bence-Jones protein was detected on the serum and urinary immunoelectrophoresis. The coexistence of chronic neutrophilic leukemia and myeloma was suspected based on the clinical features. The serum level of granulocyte-colony stimulating factor (G-CSF) was elevated. Immunohistochemically, atypical plasma cells were positive for anti G-CSF antibody. Finally, we diagnosed this patient as having a G-CSF-producing myeloma. Treatment with melphalan and prednisolone was initiated without beneficial response. He was then admitted to our hospital for ROAD therapy (ranimustine, vincristine, melphalan, and dexamethasone). The neutrophil count decreased in parallel with the serum G-CSF level. These observations indicated that the neutrophilia in this case was probably caused by a reactive response to G-CSF secreted from the myeloma cells.     

Effect of recombinant human granulocyte colony-stimulating factor (G-CSF) in the treatment of Pseudomonas aeruginosa bacteremia complicating hematologic malignancy--a preliminary study.

The efficacy of recombinant human granulocyte colony-stimulating factor (G-CSF) in the treatment of Pseudomonas aeruginosa bacteremia in cancer patients receiving intensive chemotherapy was studied retrospectively. In 14 of the 24 episodes of P. aeruginosa bacteremia, which occurred in 23 severely neutropenic patients with hematologic malignancies during a three-year period, G-CSF was given subcutaneously or intravenously at daily doses of 75 micrograms/body to 200 micrograms/m2 of body surface. Overall, survival at one week after onset was observed in 13 patients (54%). Treatment with G-CSF, however, had no statistically significant association with one-week survival, although a favorable outcome was well correlated with an increase in the neutrophil count during therapy. On the other hand, septic shock and appropriate antibiotic therapy were the major prognostic factors. The frequency of shock was reduced by appropriate therapy, but not by G-CSF treatment. These preliminary findings thus suggested that G-CSF should not be effective in the treatment of neutropenic cancer patients with P. aeruginosa bacteremia. No adverse effects of G-CSF were observed.     

Effects of rhG-CSF on neutrophil functions and bone marrow parameters in diabetic rats

Neutrophils have an important role in the host defense. The elevated serum glucose levels of diabetics affect traditional host defenses such as neutrophil counts and functions. The causes of these impairments are not clear. We aimed to investigate changes of peripheral neutrophil counts and functions and their relation with bone marrow cells in diabetic rats. Thirty-two rats were divided into four equal groups. Group 1 were controls and Groups 2 and 4 were made diabetic by a single intraperitoneal injection of streptozotocin. Granulocyte colony stimulating factor (G-CSF) was injected subcutaneously into Groups 3 and 4. White blood cell count, neutrophil counts and function and bone marrow cell count were determined. Peripheral blood cell counts, neutrophil phagocytosis index were decreased but neutrophil adhesivity index was not different in the diabetes-induced group. There was a difference in circulating white blood cell counts and neutrophil counts between the rhG-CSF treated and non-treated groups. The phagocytosis index of neutrophil in diabetic rats was significantly diminished by rhG-CSF treatment. A hyperplasia of early cells of the myeloid series in G-CSF treated groups was observed when compared with those of nontreated groups (p<0.001). A significant decrease was noted in the number of mature marrow segmented cells diabetic groups (p<0.001). Finally, G-CSF has been shown to cause neutrophilia by acting as a releasing factor for mature marrow neutrophils in diabetic rats. These results suggest that G-CSF may be used to improve nonspecific immunity in diabetic patients.     

Contrasting effects of recombinant human granulocyte-macrophage colony- stimulating factor (CSF) and granulocyte CSF treatment on the cycling of blood elements in childhood-onset cyclic neutropenia

Recombinant human granulocyte colony-stimulating factor (G-CSF) treatment has been shown to increase average neutrophil counts substantially in patients with childhood-onset cyclic neutropenia (or "cyclic hematopoiesis"), but not to eliminate the cyclic oscillations of neutrophil counts or those of other blood elements (monocytes, platelets, eosinophils, and reticulocytes) that are characteristic of this hematopoietic disorder. Indeed, oscillations of neutrophil counts are amplified during G-CSF treatment. We have compared the effects of recombinant granulocyte-macrophage-CSF (GM-CSF) with those of G-CSF in three patients with this disease (2 men and 1 woman, 17, 30, and 32 years of age). These patients were treated with GM-CSF (2.1 micrograms/kg/day, subcutaneously) for 6 weeks, preceded and followed by 6 to 13 weeks of detailed observation to document changes in the cyclic oscillations of blood neutrophils and other blood elements; two of the patients were subsequently treated with G-CSF (5.0 micrograms/kg/d, subcutaneously) and observed for comparable periods of time. Unlike G-CSF treatment, which increased average neutrophil counts more than 20-fold, GM-CSF increased neutrophil counts only modestly, from 1.6- to 3.9-fold, although eosinophilia of varying prominence was induced in each patient. However, at the same time, GM-CSF treatment dampened or eliminated the multilineage oscillations of circulating blood elements (neutrophils, monocytes, platelets, and/or reticulocytes) in each of the patients. In contrast, G-CSF treatment of the same patients markedly amplified the oscillations of neutrophil counts and caused the cycling of other blood elements (monocytes in particular) to become more distinct. These findings support the conclusion that the distinctive cycling of blood cell production in childhood-onset cyclic neutropenia results from abnormalities in the coordinate regulation of both GM-CSF-responsive, multipotential progenitor cells and G-CSF-responsive, lineage-restricted, neutrophil progenitors.     

Kinetics of peg-filgrastim after high-dose chemotherapy and autologous peripheral blood stem cell transplantation

Peg-filgrastim is a form of G-CSF with a sustained duration of action due to self-limited clearance. We administered 6 mg peg-filgrastim to 18 autograft recipients on day +1 after transplantation for hematologic malignancies. Plasma samples were collected at baseline and during transplantation. Hematopoietic recovery and clinical outcomes were compared to the historical data of 54 patients not receiving G-CSF. Patients receiving peg-filgrastim achieved a serum level of 115 000 pg/ml on day +2, 24 h after drug administration. Drug level maintained a plateau until day +8 and, after day +10, declined concomitantly with myeloid recovery. Patients experienced prompt neutrophil recovery: days +9 and +10 to 500 and 1000 neutrophils per microliter, and 4 days with an absolute neutrophil count <100 cells per microliter. Duration of antibiotic therapy was significantly shortened, but we did not observe significant differences in other end points. In conclusion, peg-filgrastim was well tolerated and efficacious, and hastened myeloid recovery.     

The effect of iron chelation on haemopoiesis in MDS patients with transfusional iron overload

Long-term follow-up data are presented on changes in peripheral blood counts and Hb requirements of 11 patients with myelodysplastic syndromes (MDS) during iron chelation treatment with desferrioxamine for up to 60 months. The erythroid marrow activity was indirectly evaluated by repeated determinations of the serum transferrin receptor concentration. The efficacy of iron chelation was evaluated by repeated quantitative determination of the liver iron concentration by magnetic resonance imaging. Reduction in the Hb requirement (≥50%) was seen in 7/11 (64%) patients. Five patients (46%) became blood transfusion independent. Platelet counts increased in 7/11 (64%) patients and the neutrophil counts in 7/9 (78%) evaluable patients. All patients in whom iron chelation was highly effective showed improvement of erythropoietic output accompanied by an increase in the serum transferrin receptor concentration. It is concluded that reduction in cytopenia in MDS patients may be accomplished by treatment with desferrioxamine, if the iron chelation is efficient and the patients are treated for a sufficiently long period of time. Exactly how treatment with desferrioxamine works remains a challenge for further investigation.