Heterozygous FGF8 mutations in patients presenting cryptorchidism and multiple VATER/VACTERL features without limb anomalies

BACKGROUND

The acronym VATER/VACTERL association describes the combination of at least three of the following cardinal features: vertebral defects, anorectal malformations, cardiac defects, tracheoesophageal fistula with or without esophageal atresia, renal malformations, and limb defects. Although fibroblast growth factor-8 (FGF8) mutations have mainly found in patients with Kallmann syndrome, mice with a hypomorphic Fgf8 allele or complete gene invalidation display, aside from gonadotropin-releasing hormone deficiency, parts or even the entire spectrum of human VATER/VACTERL association.

METHODS

We performed FGF8 gene analysis in 49 patients with VATER/VACTERL association and 27 patients presenting with a VATER/VACTERL-like phenotype (two cardinal features).

RESULTS

We identified two heterozygous FGF8 mutations in patients displaying either VATER/VACTERL association (p.Gly29_Arg34dup) or a VATER/VACTERL-like phenotype (p.Pro26Leu) without limb anomalies. Whereas the duplication mutation has not been reported before, p.Pro26Leu was once observed in a Kallmann syndrome patient. Both our patients had additional bilateral cryptorchidism, a key phenotypic feature in males with FGF8 associated Kallmann syndrome. Each mutation was paternally inherited. Besides delayed puberty in both and additional unilateral cryptorchidism in one of the fathers, they were otherwise healthy. Serum hormone levels downstream the gonadotropin-releasing hormone in both patients and their fathers were within normal range.

CONCLUSION

Our results suggest FGF8 mutations to contribute to the formation of the VATER/VACTERL association. Further studies are needed to support this observation.

[Secondary generalized brachioradial pruritus. An uncommon but easy-to-use differential diagnostic approach to generalized pruritus]

Brachioradial pruritus is a neuropathic form of chronic pruritus and mostly localized on the forearms. We report on a patient whose pruritus generalized 4 months after beginning on the forearms. The mechanism that leads to generalization is still unknown; multiplier factors may be involved. Systemic therapy with anticonvulsants and physical therapy measures produced improvement. This form of pruritus requires a focused, interdisciplinary diagnostic approach and therapy.

Involvement of the WNT and FGF signaling pathways in non-isolated anorectal malformations: sequencing analysis of WNT3A, WNT5A, WNT11, DACT1, FGF10, FGFR2 and the T gene

Anorectal malformations (ARMs) comprise a broad spectrum of anomalies, including anal atresia, congenital anal fistula and persistence of the cloaca. Research suggests that genetic factors play an important role in ARM development. However, few genetic variants have been identified. Embryogenesis is orchestrated by crosstalk of the wingless-type MMTV integration site family (WNT) and fibroblast growth factor (FGF) signaling pathways in a process that involves several intracellular cascades. Studies in mice have implicated several genes from these pathways in the etiology of ARMs. We performed sequencing analysis of seven of these previously reported genes in 78 patients with ARMs occurring within the context of at least one additional congenital anomaly. No associations were identified with variants in WNT3A, WNT5A, WNT11, DACT1, FGF10 or the T gene. In the FGFR2 gene, three novel heterozygous nucleotide substitutions were identified. Further investigations, including the study of family members, revealed that these variants were not causally related to the phenotype in the present ARM cohort. Mutations in the seven investigated genes may nonetheless be a cause of ARMs in rare cases. However, further studies should consider genes encoding other proteins in the WNT/FGF signaling pathways as possible candidates.

First measurement of Bose-Einstein correlations in proton-proton collisions at √s=0.9 and 2.36 TeV at the LHC

Bose-Einstein correlations have been measured using samples of proton-proton collisions at 0.9 and 2.36 TeV center-of-mass energies, recorded by the CMS experiment at the CERN Large Hadron Collider. The signal is observed in the form of an enhancement of pairs of same-sign charged particles with small relative four-momentum. The size of the correlated particle emission region is seen to increase significantly with the particle multiplicity of the event.

Transverse-momentum and pseudorapidity distributions of charged hadrons in pp collisions at square root of s = 7 TeV

Charged-hadron transverse-momentum and pseudorapidity distributions in proton-proton collisions at square root of s = 7  TeV are measured with the inner tracking system of the CMS detector at the LHC. The charged-hadron yield is obtained by counting the number of reconstructed hits, hit pairs, and fully reconstructed charged-particle tracks. The combination of the three methods gives a charged-particle multiplicity per unit of pseudorapidity dN(ch)/dη|(|η|<0.5) = 5.78 ± 0.01(stat) ± 0.23(syst) for non-single-diffractive events, higher than predicted by commonly used models. The relative increase in charged-particle multiplicity from square root of s = 0.9 to 7 TeV is [66.1 ± 1.0(stat) ± 4.2(syst)]%. The mean transverse momentum is measured to be 0.545 ± 0.005(stat) ± 0.015(syst)  GeV/c. The results are compared with similar measurements at lower energies.

Determinants of glucose control in patients with chronic pancreatitis

AIMS/HYPOTHESIS

Diabetes frequently develops in patients with chronic pancreatitis (CP). Partial pancreatectomy has emerged as a treatment option for such patients. We addressed whether the development of diabetes in CP patients is related to pancreatic beta cell area or clinical variables, and which factors predict the diabetes risk after partial pancreatectomy.

METHODS

Fractional beta cell area was determined in pancreatic tissue samples obtained from 114 CP patients undergoing pancreatic surgery and related to measures of glucose control, as well as clinical and anthropometric data. Seventy-four patients without diabetes at the time of surgery were contacted again 2.5 +/- 1.0 years after partial pancreatectomy in order to obtain information about the post-operative development of diabetes.

RESULTS

In the surgical samples in the whole cohort, pancreatic beta cell area was 0.40 +/- 0.06% in patients with and 0.64 +/- 0.06% in those without previously known diabetes (p = 0.039). There was an inverse non-linear relationship between pancreatic beta cell area and fasting glucose concentrations (r = 0.29) as well as HbA(1c) levels (r = 0.36). Nineteen out of 74 previously normoglycaemic patients (26%) developed diabetes over an average period of 2.5 years of follow-up. Pre-operative fasting glucose levels, HbA(1c) and BMI were identified as predictors of diabetes after partial pancreatectomy. However, pancreatic beta cell area did not differ in those who subsequently developed diabetes (0.66 +/- 0.15%) and those who did not (0.62 +/- 0.08%, p = 0.45).

CONCLUSIONS/INTERPRETATION

Hyperglycaemia in CP patients is associated with reduced beta cell area. However, reduced beta cell area does not predict the development of diabetes, suggesting that other factors are more important determinants of alterations in glucose metabolism in patients with CP.

Altered function and surface marker expression of neutrophils induced by rhG-CSF treatment in severe congenital neutropenia

Neutrophils from patients suffering from severe congenital neutropenia (SCN), who were receiving recombinant human granulocyte colony-stimulating factor (rhG-CSF), were investigated in order to analyze the previously described decrease in chemotaxis. This study demonstrated the decreased chemotaxis to five well-known chemoattractants, FMLP, C5a, IL-8, LTB4 and PAF. To further investigate this impairment of patients' neutrophils, receptors and receptor turnover for chemoattractants were examined using flow cytometry. We found 1) increased FMLP receptor and decreased C5a receptor expression, 2) a normal expression of intracellular FMLP receptors after incubation with PMA, 3) increased loss and decreased re-expression of FMLP receptors after incubation with this peptide, 4) normal expression of adhesion glycoproteins CR3 (CD11b/CD18) and LFA1 (CD11a/CD18), 5) further signs of in vivo preactivation: high expression of Fc gamma-RI (CD64) and Fc gamma-RII (CD32), decreased expression of Fc gamma-RIII (CD16), increased expression of CD14, and low expression of HLA-DR. These data demonstrate that the decrease of chemotaxis of neutrophils from SCN patients is not due: a) to a decrease in the number of intra- or extracellular FMLP receptors; b) to a decrease of adhesion molecules. However, the decreased chemotaxis could result from an altered FMLP receptor turnover. The relevance of the altered Fc gamma-receptor pattern for the in vivo occurrence of side-effects, e.g. the necrotic vasculitis, of G-CSF treatment is discussed.

[Congenital bone marrow failure syndromes. The last 20 years by the example of congenital neutropenia]

Congenital bone marrow failure syndromes are rare diseases characterised by a reduction of mature blood cells (erythrocytes, platelets, neutrophils). Examples of such disorders include congenital aplastic anemia (Fanconi anemia), congenital hypoplastic anemia (Diamond-Blackfan anemia), congenital neutropenias (Kostmann syndrome, cyclic neutropenia, Shwachman-Diamond syndrome and others), and congenital thrombocytopenias (TAR syndrome, amegacaryocytic thrombocytopenia). In Germany the prevalence of congenital bone marrow failure syndromes can be estimated to be 10/1,000,000 children and adolescents. Although rare, these diseases contributed significantly to the current knowledge on normal haematopoiesis. The documentation of rare diseases by patient registries and the cooperation of clinical centres within networks are most important for the resolution of such disorders. In the following, congenital neutropenia will be presented as an example: Until the 1980s congenital neutropenia could only be classified clinically. Few cases had been reported in the literature. All subtypes were therefore collected under the general term "congenital neutropenia". The establishment of an international network of experts and the long-term documentation of the courses of disease in a common database allowed for statistically workable data in response to therapy, secondary diagnoses and the long-term prognosis. A close cooperation with scientists finally led to the characterisation of genetically different disorders with common pathomechanisms.

Chromosomal aberrations in congenital bone marrow failure disorders—an early indicator for leukemogenesis?

As chromosomal instability may contribute to leukemogenesis in patients with congenital bone marrow failure (CBMF) disorders, it was the aim of this study to characterize chromosomally aberrant clones that arise during the clinical course of disease by means of R-banding and fluorescence in situ hybridization (FISH) analyses. In addition, multicolor-FISH and array-comparative genomic hybridization (CGH) were applied to characterize clonal chromosome aberrations in more detail. Between January 2004 and December 2005, we prospectively analyzed 90 samples of 73 patients with proven or suspected CBMF disorders enrolled in a German Study Network of CBMF diseases. Clonal aberrations could be identified in four of 73 patients examined. In one child with congenital thrombocytopenia, Jacobsen syndrome [del(11)(q24)c] was diagnosed, and thus a CBMF could be excluded. In a girl with Shwachman-Diamond syndrome, two independent clones, one with an isochromosome i(7)(q10), another with a complex aberrant karyotype, were identified. Simultaneously, transition into a myelodysplastic syndrome (MDS) occurred. The brother, who was also afflicted with Shwachman-Diamond syndrome, showed an isochromosome i(7q) as a single aberration. In the fourth patient with severe congenital neutropenia, an add(21)(q22) marker containing a low-level amplification of the AML1 gene was identified at the time point of transition into acute myelogenous leukemia (AML). In summary, we suggest that follow-up of patients with CBMF using chromosome and FISH analyses will be helpful for the early detection of transition into MDS or AML and thus should be an integral part of the clinical management of these patients.

Substitution of cyclophosphamide and busulfan by fludarabine, treosulfan and melphalan in a preparative regimen for children and adolescents with Shwachman–Diamond syndrome

Allogeneic hematopoietic stem cell transplantation (HSCT) is the only definitive treatment for severe bone marrow dysfunction and clonal disorders in patients diagnosed with Shwachman-Diamond syndrome (SDS). In an attempt to minimize regimen-related toxicity (RRT), we have initiated a fludarabine/treosulfan/melphalan-based pilot protocol avoiding the combination of busulfan and cyclophosphamide. Median age at transplantation was 9.6 years (range 1.5-17 years). All three patients received conditioning with fludarabine (30 mg/m2/day x 6), treosulfan (12 g/m2/day x 3) and melphalan (140 mg/m2/day x 1). CAMPATH-1H (0.1 mg/kg x 2) was added in two cases, while rabbit ATG (Genzyme; 3 x 2.5 mg/kg) was given to the cord blood recipient. One patient was transplanted with a non-manipulated marrow graft from an HLA-identical sibling, one with a marrow graft from a 10/10 matched unrelated donor, and one with a 9/10 matched unrelated umbilical cord blood (UCB) unit. Mean cell doses given were 3.6 x 10(8) nucleated cells/kg BW for the bone marrow recipients and 4.2 x 10(7) nucleated cells/kg BW for UCB recipient. Overall, two of three patients are alive and display 100% donor chimerism. Acute graft-versus-host disease grade II was seen in one patient, while no GVHD exceeding grade I occurred in the remaining two.

Diagnostik und Behandlung alkoholbezogener Störungen

BACKGROUND

Due to their high prevalence alcohol related disorders (dependent, harmful and at risk drinking) are of major importance for the general practitioner (GP). The aim of this study was to examine the diagnostic and treatment strategies employed by the general practitioners.

METHODS

A standardized 10-page questionnaire was mailed to a representative sample (n = 1232) of the general practitioners in south-west Germany. They were asked about diagnostic and therapeutic procedures they had employed in the last patient seen. Further questions regarded patient-related and structural problems. The response rate was 24.3 %.

RESULTS

The reported patients had a mean age of 49 +/- 10.3 years. 70.6 % were of male sex. The mean duration of the last patient contact was 18.7 minutes. The diagnosis originated more in clinical impression than in use of screening instruments (0.7 % of patients) or formal diagnostic criteria. 76.7 % fulfilled ICD-10 criteria for dependent drinking, 65.0 % were judged dependent drinkers by the GP's. In most cases the patient had been referred to inpatient services. The main intervention (97.3 % of cases) was disease related counseling. 69.4 % were judged to be quite ill and severely ill. In most cases an inpatient referral had taken place. Pharmacotherapeutic measures were relatively rarely employed (11.3 %). As the major impediments of treatment patient related factors were stated (lack of acceptance of diagnosis, resistance to treatment).

DISCUSSION

The majority of patients described by the GP's were dependent drinkers. This indicates that many at risk drinkers might perhaps not be correctly identified. Concerning therapeutic competency patient-related factors are considered as the major impediments for the delivery of effective care. This reflects a view of GP's that patients with alcohol problems are being difficult and time consuming. This should be carefully addressed by future GP-education programs.

Mutations in the gene encoding neutrophil elastase (ELA2) are not sufficient to cause the phenotype of congenital neutropenia

Mutations in the ELA2 gene encoding human neutrophil elastase have been reported recently to be involved in the aetiology of both, cyclic (CyN) and congenital neutropenia (CN). We analysed the correlation between the occurrence of ELA2 mutations and the neutropenic phenotype in a family with two children affected with CN. The two children harboured the same heterozygous mutation in the ELA2 gene that was inherited from their unaffected father. We conclude that ELA2 mutations are not the single cause of CN although they might be a necessary prerequisite for the expression of the neutropenic phenotype in a subgroup of CN patients.

[Cyclic neutropenia. Detection of a mutation in the gene for neutrophil elastase (ELA2)]

BACKGROUND AND OBJECTIVE

Cyclic neutropenia is a rare congenital hematopoietic disease which occurs sporadically or as an autosomal dominantly inherited disorder. Recently, the locus for cyclic neutropenia was mapped to chromosome 19p13.3. Autosomal dominant and sporadic cyclic neutropenia are now attributable to mutations of the ELA2 gene encoding neutrophil elastase.

PATIENTS/METHODS

Based on a case report we review the clinical picture and diagnostic criteria of cyclic neutropenia and report about the recent molecular biological findings and current treatment options.

RESULTS

Serial blood cell counts revealed the characteristic oscillations of the circulating neutrophils with 21-day periodicity from near normal to extremely low levels. The neutrophil nadir lasted 3-5 days. The neutropenia was associated with fever, malaise, painful oral aphthous ulcers and lymphadenopathy. Mutational analysis of the patient's genomic DNA revealed a single base-pair transition (nt 4716, G-->A) in intron 4 of ELA2. Since the initiation of therapy with subcutaneous recombinant human granulocyte-stimulating colony factor (rHuG-CSF) 24 months ago, the patient has been free of symptoms.

CONCLUSIONS

Despite the typical medical history with onset of the symptoms in early infancy the diagnosis of cyclic neutropenia was not established until the age of 9 years. A common reason for the delayed diagnosis of cyclic neutropenia may be unawareness of the rare but distinctive disorder and the practice of obtaining screening blood counts without leukocyte differentials. Patients with cyclic neutropenia should be enrolled to the Severe Chronic Neutropenia International Registry (SCNIR).

Time course of increasing numbers of mutations in the granulocyte colony-stimulating factor receptor gene in a patient with congenital neutropenia who developed leukemia

Point mutations in the granulocyte colony-stimulating factor receptor (G-CSFR) gene have been linked to the development of secondary leukemia in patients with congenital neutropenia (CN). This report presents data on a now 18-year-old patient with CN who has received G-CSF treatment since 1989 and who developed acute myeloid leukemia (AML) in 1998. To evaluate whether there is an association between the occurrence of point mutations of the G-CSFR gene and development of secondary AML, DNA/messenger RNA of neutrophils and mononuclear cells from this patient were analyzed at different time points by polymerase chain reaction and subsequent cloning by DNA sequencing of representative numbers of individual clones. Findings suggest an increasing instability of the G-CSFR gene in time as judged by increasing numbers of mutations proposed to be one important step in the development of AML in this patient.

Mutations in the gene encoding neutrophil elastase in congenital and cyclic neutropenia

Congenital neutropenia and cyclic neutropenia are disorders of neutrophil production predisposing patients to recurrent bacterial infections. Recently the locus for autosomal dominant cyclic neutropenia was mapped to chromosome 19p13.3, and this disease is now attributable to mutations of the gene encoding neutrophil elastase (the ELA2 gene). The authors hypothesized that congenital neutropenia is also due to mutations of neutrophil elastase. Patients with congenital neutropenia, cyclic neutropenia, or Shwachman-Diamond syndrome were referred to the Severe Chronic Neutropenia International Registry. Referring physicians provided hematologic and clinical data. Mutational analysis was performed by sequencing polymerase chain reaction (PCR)-amplified genomic DNA for each of the 5 exons of the neutrophil ELA2 gene and 20 bases of the flanking regions. RNA from bone marrow mononuclear cells was used to determine if the affected patients expressed both the normal and the abnormal transcript. Twenty-two of 25 patients with congenital neutropenia had 18 different heterozygous mutations. Four of 4 patients with cyclic neutropenia and 0 of 3 patients with Shwachman-Diamond syndrome had mutations. For 5 patients with congenital neutropenia having mutations predicted to alter RNA splicing or transcript structure, reverse transcriptase-PCR showed expression of both normal and abnormal transcripts. In cyclic neutropenia, the mutations appeared to cluster near the active site of the molecule, whereas the opposite face was predominantly affected by the mutations found in congenital neutropenia. This study indicates that mutations of the gene encoding neutrophil elastase are probably the most common cause for severe congenital neutropenia as well as the cause for sporadic and autosomal dominant cyclic neutropenia.

[Severe congenital neutropenia: trends in diagnosis and therapy]

Severe congenital neutropenia (CN; Kostmann syndrome) is a hematologic disorder characterized by a maturation arrest of myelopoiesis at the promyelocyte/myelocyte stage of development. This arrest results in severe neutropenia with absolute neutrophil counts (ANC) less than 0.2 x 10(9)/l associated with severe systemic bacterial infections from early infancy. Data on over 300 patients with CN collected by the Severe Chronic Neutropenia International Registry (SCNIR) since 1994 indicate that > 90% of these patients respond to recombinant human granulocyte-colony stimulating factor (rHuG-CSF) treatment with an ANC > 1.0 x 10(9)/l. In these patients rHuG-CSF is required daily as subcutaneous injection with individual doses ranging between 0.27 and 120 mcg/kg/day to maintain ANC above 1.0 x 10(9)/l. Adverse events documented in this group of patients include splenomegaly, thrombocytopenia, osteoporosis and malignant transformation into MDS/leukemia. If and how rHuG-CSF treatment impacts on these adverse events remains unclear since there are no historical controls for comparison. For those patients who are refractory to rHuG-CSF treatment and continue to have severe and often life-threatening bacterial infections, hematopoietic stem cell transplantation (HSCT) is still the only currently available treatment.

Stem cell transplantation in patients with severe congenital neutropenia without evidence of leukemic transformation

Severe congenital neutropenia (CN) (Kostmann syndrome) is a hematologic disorder characterized by a maturation arrest of myelopoiesis at the promyelocyte/myelocyte stage of development. This arrest results in severe neutropenia leading to absolute neutrophil counts (ANC) below 0.2 x 10(9)/L associated with severe bacterial infections from early infancy. Data on over 300 patients with CN collected by the Severe Chronic Neutropenia International Registry (SCNIR) beginning in 1994 indicate that more than 90% of these patients respond to recombinant human granulocyte-colony stimulating factor (r-HuG-CSF) treatment with an ANC greater than 1. 0 x 10(9)/L. For patients who are refractory to r-HuG-CSF treatment and continue to have severe and often life-threatening bacterial infections, hematopoietic stem cell transplantation is the only currently available treatment. We report on a total of 11 patients with CN reported to the SCNIR who underwent transplantation for reasons other than malignant transformation between 1976 and 1998. Of these patients, 8 were nonresponders or showed only partial response to r-HuG-CSF treatment with ongoing infections. Results from these patients suggest that transplantation of stem cells from an HLA-identical sibling is beneficial for patients refractory to r-HuG-CSF. (Blood. 2000;95:1195-1198)

Alkaline phosphatase activity in neutrophils from patients with severe congenital neutropenia (Kostmann's syndrome)

The glycoprotein alkaline leukocyte phosphatase (ALP) can be used as a marker of maturity in neutrophilic granulocytes as the activity of ALP increases during neutrophilic differentiation. Severe congenital neutropenia (SCN) or Kostmann's syndrome is a congenital disorder characterized by a maturation arrest of myeloid progenitor cells at the promyelocyte/myelocyte stage that can be treated with recombinant human granulocyte colony-stimulating factor (rhG-CSF). Until recently there have been no reports on ALP activity in neutrophils of patients suffering from SCN, despite the fact that ALP is an important correlate of the functional activity of normal neutrophils. Thus, we conducted experiments to assess ALP activity in neutrophils from eight SCN patients before initiation of rhG-CSF treatment and an additional 17 SCN patients already receiving rhG-CSF. All eight patients analyzed before initiation of rhG-CSF treatment showed ALP activity in their neutrophilic cells. Four patients had normal and four patients had elevated ALP levels. Of the 17 patients already on treatment with rhG-CSF, 15 patients showed elevated ALP activity levels, one patient had normal ALP levels, and one patient showed abnormally low ALP activity. Thus, with the exception of a single patient, we observed normal or elevated ALP activity in neutrophils from SCN patients. As described in studies on the effect of rhG-CSF on ALP activity in healthy individuals, ALP activity was higher in SCN patients already on treatment with rhG-CSF. Therefore, our results indicate that SCN patients are not deficient in ALP activity and suggest that ALP is not deregulated in the majority of these patients.

Relapse and clonal disease in children with aplastic anemia (AA) after immunosuppressive therapy (IST): the SAA 94 experience. German/Austrian Pediatric Aplastic Anemia Working Group

Since the introduction of combined immunosuppressive therapy (IST) into management of aplastic anemia (AA) in childhood response and probability of survival improved. In contrast to bone marrow transplantation (BMT), however, patients after IST are not considered cured as high rates of relapse and development of clonal disease demonstrate. From 11/93 to 9/97 114 children (65 m, 49 f; median age 9.5 y.) from 37 centers in Germany and Austria were registered in the SAA 94 study. 86 patients lacking a matched sibling donor received IST. Most of the patients suffered from very severe (VSAA: PMN < 200/microliter) or severe AA (SAA: PMN < 500/microliter). All patients were treated with combined IST consisting of ALG and Cyclosporin A (CSA). VSAA and SAA patients were additionally treated with G-CSF. Therapy response was evaluated at day 112, after 6, 12 and 18 months. 8/86 patients died, the probability of survival being 87% after 4 years. At d 112 61% of evaluable patients became independent of transfusions (IST response: CR + PR), 13% with normal blood counts (CR). After 6 months 33% showed CR. At 12 and 18 months response improved to 74% resp. 80%, 39% resp. 55% CR. The best response was achieved in the subgroup of VSAA with 90% (PR + CR) and 65% CR after 18 months. 4 patients developed AML 3-19 months after the beginning of IST. In 2/4 pts. an aberrant clone (-7; 5q-) could be detected retrospectively in BM at diagnosis of AA. 3 nonresponders developed chromosomal aberrations (+19; -7, +12; +8) after 4, 12 and 16 months without morphological signs of AML or MDS. Overall 11 relapses occurred at a median time of 12 months (range 5-27 months) after the beginning of IST. 2 of them relapsed under CSA therapy, 2 under tapering of CSA and 7 after cessation of CSA. 7 patients responded again to CSA monotherapy. Overall response rate is 77% with a probability of event free survival (EFS) of 54% after 4 years regarding all complications mentioned as events.

High incidence of significant bone loss in patients with severe congenital neutropenia (Kostmann's syndrome)

OBJECTIVE

Clinical observation of bone pain, unusual fractures in two patients, and diffuse osteopenia/osteoporosis led us to assess bone mineral content and density in 30 patients with severe congenital neutropenia who were treated with recombinant-methionyl-human granulocyte colony-stimulating factor (r-metHuG-CSF).

STUDY DESIGN

We reviewed roentgenograms in 29 of these 30 patients to evaluate bone loss before and during treatment. In addition, in 17 of the 30 patients, bone mineral status could be assessed by both quantitative computed tomography (Q-CT; n = 16) and dual energy x-ray absorptiometry (DXA; n = 1). In one patient, Q-CT was not possible because of severe vertebral fractures.

RESULTS

Of the 30 patients investigated, 15 had evidence of osteopenia/osteoporosis observed on spine radiographs (n = 5), on Q-CT/DXA (n = 1/n = 1), or on radiographs and Q-CT (n = 8). In 13 of the 30 patients, only a lateral radiograph of the lumbar spine was available, 5 of 13 showing either increased kyphosis and wedging of the vertebrae or compression fractures of the vertebral bodies, indicating severe established osteoporosis. In eight patients, the findings of the spinal radiographs were normal. In nine patients, spinal radiographs were taken before r-metHuG-CSF treatment. Osteoporotic vertebral deformation (n = 3) or reduced bone mass (n = 3) was seen in six of these nine patients. The levels of serum biochemical markers of bone metabolism were all within normal ranges except for mild elevation of the serum alkaline phosphatase level. The degree of spinal bone mineral loss did not correlate with dose and duration of r-metHuG-CSF treatment or with the age or sex of the patients.

CONCLUSIONS

These data indicate a high incidence of bone mineral loss in children with severe congenital neutropenia. The underlying pathogenesis of bone demineralization is not clear. It is more likely that the bone loss was caused by the pathophysiologic features of the underlying disease, but it is possible that r-metHuG-CSF accelerates bone mineral loss.

Long-term safety of treatment with recombinant human granulocyte colony-stimulating factor (r-metHuG-CSF) in patients with severe congenital neutropenias

Congenital neutropenias include a heterogenous group of diseases characterized by a decrease in circulating neutrophils. In phase I/II/III studies in patients with severe congenital and cyclic neutropenia, treatment with recombinant human granulocyte colony-stimulating factor (r-metHuG-CSF) resulted in a rise in the absolute neutrophil counts (ANC) and a reduction in infections. We report the effects of long-term safety of subcutaneous r-metHuG-CSF administration in 54 patients (congenital n = 44. cyclic n = 10) treated for 4-6 years. A sustained ANC response was seen in 40/44 severe congenital neutropenia patients and 10/10 cyclic neutropenia patients. Two patients required an increase of > 25% in dose to maintain a clinical response; one patient became refractory to therapy. A significant decrease in the incidence of severe infections and the need for intravenous antibiotics was noted. Significant adverse events noted which may or may not be related to therapy included: osteopenia (n = 15), splenomegaly (n = 12), hypersplenism (n = 1), vasculitis (n = 2), glomerulonephritis (n = 1), BM fibrosis (n = 2), MDS/leukaemia (n = 3), and transient inverted chromosome 5q with excess blasts (n = 1). R-metHuG-CSF has been well tolerated in the majority of patients and resulted in a long-term improvement in their clinical status.

[Long-term treatment with recombinant human granulocyte colony stimulating factor in patients with severe congenital neutropenia]

Severe congenital neutropenia is a disorder of myelopoiesis characterized by severe neutropenia secondary to either a maturational arrest of myelopoiesis at the level of promyelocytes (Kostmann-Syndrome; SCN) or regular cyclic fluctuations in the number of blood neutrophils with a median ANC below 500/microliter (cyclic neutropenia). We have treated 32 patients with SCN and 4 patients with cyclic neutropenia. Thirty of 32 patients with SCN and all 4 patients with SCN responded to r-met HuG-CSF treatment with an increase of the median ANC to above 1000/microliter. The doses needed to achieve and maintain the response varied between 0.8 and 120 micrograms/kg/d. Long-term treatment did not exhaust the myelopoiesis: The mean ANC remained stable up to 5 years of treatment. The increase in ANC was associated with dramatic clinical responses: significant reduction of severe bacterial infections, reduction of intravenous antibiotic treatment episodes, and reduction of hospitalizations. No severe bacterial infections occurred in any of the r-met HuG-CSF responders during long-term treatment. Severe adverse event, most likely associated with the underlying disease, included the development of MDS/Leukemia in two patients, and osteopenia/osteoporosis in 12 patients. These results demonstrate the beneficial effects of r-met HuG-CSF treatment in severe congenital neutropenia patients.

In vivo effects of interleukin-6 on thrombopoiesis in healthy and irradiated primates

We have studied the in vivo effects of recombinant human interleukin-6 (rhIL-6) on hematopoiesis in eight healthy and nine irradiated cynomolgus monkeys. Of the healthy animals, three received rhIL-6 alone (10 micrograms/kg/d, subcutaneously [SC]), one received rhIL-6 in combination with rhIL-3 (10 micrograms/kg/d, SC), one received rhIL-6 in combination with recombinant cynomolgus granulocyte-macrophage colony-stimulating factor (rcGM-CSF; 10 micrograms/kg/d, SC), two received rhIL-6 in combination with recombinant human granulocyte-CSF (rhG-CSF; 10 micrograms/kg/d, SC), and one received rhIL-6 in combination with recombinant human leukemia inhibitory factor (rhLIF; 10 micrograms/kg/d, SC). All animals were treated for at least 2 weeks with rhIL-6 or the above mentioned combinations. rhIL-6 alone significantly increased the peripheral blood platelet counts (2- to 3.5-fold). The platelets reached a plateau between days 10 and 15 of treatment. No synergistic effects on platelet numbers were observed when rhIL-6 was combined with rhIL-3, rcGM-CSF, rhG-CSF, or rhLIF. In addition to rhIL-6, only rhLIF increased the platelet numbers when administered alone. To test whether rhIL-6 might also protect the animal from thrombocytopenia or shorten the time of thrombocytopenia after irradiation, we treated nine animals with total body irradiation (3.8 Gy). Six of the animals were additional treated with rhIL-6 (4 with 10 micrograms/kg/d; and 2 with 100 micrograms/kg/d) from day -1 or +1 to day 28 post irradiation. In these animals, rhIL-6 at the same dose effective in healthy animals (10 micrograms/kg/d) was not capable of protecting the animals from platelet nadir. However, when pegylated rhIL-6 was used at a dosage of 100 micrograms/kg/d post irradiation, the mean of the nadirs was 71,000/microL as compared with 39,000/microL in control animals and the time of thrombocytopenia was shorter (3 v 5 days). In all animals (healthy and irradiated), rhIL-6 did not increase the number of bone marrow megakaryocytes but induced a right shift of DNA ploidy in megakaryocytes. These data suggest that IL-6 acts as "thrombopoietin"-like activity, but not as "megakaryocyte-CSF"-like activity.

Granulocyte and granulocyte-macrophage colony-stimulating factors for treatment of neutropenia in glycogen storage disease type Ib

Two children with glycogen storage disease type Ib associated with numerous recurrent bacterial infections as a result of neutropenia and neutrophil dysfunction were treated with recombinant human granulocyte colony-stimulating factor (G-CSF). One of the two patients was previously treated with recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF); therapy had to be discontinued because of severe local side effects. Both colony-stimulating factors at dosages of 3 and 8 micrograms/kg/per day, respectively, increased the average neutrophil counts from less than 300 cells/microliters to more than 1200 cells/microliters. Two subpopulations of neutrophils could be identified by their capacity to produce H2O2: one subpopulation generated H2O2 normally and a second was defective in H2O2 production. The doses of G-CSF effectively enhanced and maintained that subpopulation of neutrophils which produced normal amounts of H2O2. Moreover, these colony-stimulating factor-induced neutrophils demonstrated effective phagocytosis of zymosan particles and killing of staphylococci. Chemotaxis was decreased and could not be normalized by treatment with G-CSF. We conclude that maintenance treatment with G-CSF improved the quality of life in both patients: The number and severity of bacterial infections decreased markedly during treatment. Long-term treatment with G-CSF (12 and 10 months, respectively) was well tolerated, and no adverse clinical events were observed.

Increased serum levels of granulocyte colony-stimulating factor in patients with severe congenital neutropenia

Severe congenital neutropenia (SCN), also known as Kostmann Syndrome, is characterized by a maturation arrest of myelopoiesis at the level of promyelocytes with absence of neutrophils in bone marrow (BM) and blood. Hypotheses of the pathophysiology of SCN include (1) defective production of granulocyte colony-stimulating factor (G-CSF), and/or (2) defective response to G-CSF. To exclude defective G-CSF production we tested sera from patients with SCN for the presence of G-CSF using Western blot analysis and NFS-60 proliferation assay. Using these assays we were able to detect increased G-CSF serum levels in SCN patients (150 to 910 pg/mL) as compared with normal controls (between undetectable and 100 pg/mL). These results suggest that patients with SCN have no defect in G-CSF production but a defective response of neutrophil precursors to endogenous G-CSF.

Blood mononuclear cells from patients with severe congenital neutropenia are capable of producing granulocyte colony-stimulating factor

Severe congenital neutropenia (SCN) is a disorder of myelopoiesis characterized by severe neutropenia or absence of blood neutrophils secondary to a maturational arrest at the level of promyelocytes. We examined peripheral blood mononuclear cells (PBMC) of SCN patients who demonstrated normalization of their blood neutrophil counts in a phase II clinical study with recombinant human granulocyte colony-stimulating factor (rhG-CSF). When stimulated in vitro with bacterial lipopolysaccharides (LPS), PBMC of those SCN patients produced G-CSF activity, as judged by proliferation induction of the murine leukemia cell line, NFS-60. Western and Northern blot analysis showed G-CSF protein and G-CSF-mRNA indistinguishable in size from those of normal controls. We conclude that PBMC of the SCN patients tested are capable of synthesizing and secreting biologically active G-CSF in vitro.

In vitro functions of neutrophils induced by treatment with rhG-CSF in severe congenital neutropenia

Neutrophils (and monocytes) from 5 patients suffering from severe congenital neutropenia (SCN) were investigated in vitro after induction of this cell type by treatment with recombinant human granulocyte colony-stimulating factor (rh G-CSF) in vivo. Some abnormal morphological features were seen, such as anomalies of nuclei of phagocytes. No limitations were found 1) in the ability of neutrophils and monocytes to produce reactive oxygen intermediates (ROI) following stimulation with phorbol-myristate-acetate (PMA), 2) in the ability of neutrophils to phagocytose particles of zymosan A and to produce ROI simultaneously and 3) in the ability to kill bacteria of the species staphylococcus aureus. However the specific migration of neutrophils in a gradient of FMLP under soft agar was decreased to approximately 50% in all patients tested as compared to healthy controls. In addition, spontaneous motility was decreased in one patient. Nevertheless, the good clinical improvements of patients suffering from SCN after treatment with rh G-CSF appeared to be due to induction of neutrophils displaying overall good functional activities with respect to natural defense.

Differential effects of granulocyte-macrophage colony-stimulating factor and granulocyte colony-stimulating factor in children with severe congenital neutropenia

Severe congenital neutropenia (SCN) is a disorder of myelopoiesis characterized by severe neutropenia secondary to a maturational arrest at the level of promyelocytes. We treated five patients with SCN with recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) for 42 days and subsequently, between 1 and 3 months later, with rhG-CSF for 142 days. The objective was to evaluate the safety and ability of these factors to elicit a neutrophil response. rhGM-CSF was administered at a dose of 3 to 30 micrograms/kg/d (30 to 60 minutes, intravenously). In all patients, a specific, dose-dependent increase in the absolute granulocyte counts was observed. However, in four patients this increase was due to an increase in eosinophils, and in only one patient it was due to an increase in the absolute neutrophil counts (ANC). Subsequently, all patients received rhG-CSF at a dose of 3 to 15 micrograms/kg/d subcutaneously. In contrast to rhGM-CSF treatment, all five patients responded to rhG-CSF during the first 6 weeks of treatment with an increase in the ANC to above 1,000/microL. The level of ANC could be maintained during maintenance treatment. In one patient, the increase in ANC was associated with an improvement of a severe pneumonitis caused by Peptostreptococcus and resistant to antibiotic treatment. No severe bacterial infections occurred in any of the patients during CSF treatment. All patients tolerated rhGM-CSF and rhG-CSF treatment without severe side effects. These results demonstrate the beneficial effect of rhG-CSF in SCN patients.