Chronic Idiopathic Neutropenia Research Articles

Cyclic Neutropenia, Congenital and Idiopathic Neutropenia

Background: Cyclic neutropenia (CyN) is an autosomal dominant disease usually attributable to mutations in the gene for neutrophil elastase, ELANE . The diagnosis depends upon serial blood counts (at the minimum every other day or three days a week for 6 weeks) showing periods of severe neutropenia (absolute neutrophil count [ANC] < 0.2 x 109/L) recurring at approximately 21 day intervals. The diagnosis can be confirmed by Lomb periodogram analysis. Genetic testing is helpful but not diagnostic because of the overlap of the mutational patterns in ELANE for CyN and severe congenital neutropenia (SCN).Methods: We reviewed clinical and laboratory data for 87 patients enrolled in the Severe Chronic Neutropenia International Registry (SCNIR) with a diagnosis of CyN in 41 kindreds. Their family histories indicated that there were 117 other neutropenic family members. For this review we focused on 53 CyN patients in 15 kindreds who met the following criteria: two or more patients within the kindred had 10 or more CBCs available for analysis. Using data collected before treatment with G-CSF by the patients' primary physicians, we examined graphically displayed serial ANC's for each affected family member and performed periodogram analysis. We compared patterns of ANC fluctuations within families and for patients of similar ages within these families.Findings and implications: •Within families, if 1 patient has a mutation in ELANE, all other neutropenic members will have the same mutation in ELANE.•Within families if the index case has typical and diagnostic oscillations in blood neutrophils, other affected family members often have neutropenia without clear or diagnostic oscillations in their counts. If the patient has a mutation in ELANE, the diagnosis of SCN is sometimes assigned.•In familial CyN the oscillations tend to dampen with lower peaks and somewhat less severe neutropenia in older adults (> 30 years of age). Unless these patients have genetic testing showing a mutation in ELANE or another gene associated with neutropenia, they may be given the diagnosis of chronic idiopathic neutropenia.•The Lomb periodogram is very useful for diagnosing CyN. It is a web-based tool readily accessible on the SCNIR web site, https://depts.washington.edu/registry/. However, it is necessary to collect sufficient number of counts (usually at least 20 counts spaced at regular intervals) to use this method to make the diagnosis of CyN. Although visually there was cycling in at least one member of the 15 families, only 5 families had a member who had CyN with a 95 or 99 percent confidence level based on the Lomb periodogram.Conclusions:Careful family history and serial measurements of ANCs are the foundations for the diagnosis of CyN. Genetic sequencing and identification of specific mutations in ELANE are helpful for prognosis. The Lomb periodogram is helpful, but requires a robust series of counts to assure that cycling is present with a high (95%) confidence level. DisclosuresDale:Genzyme (now owned by Sanofi-Aventis): Consultancy, Patents & Royalties, Research Funding; Genkyotex: Other: DSMB (work completed 6/2015); Hospira: Consultancy; Prolong: Consultancy; Boheringer-Ingelheim: Consultancy; Coherus: Consultancy; Omeros: Other: DSMB; Shire: Other: Independent Review Board; X4Pharma: Research Funding; Philips: Research Funding; Wolter Kluwer: Other: Editor, Current Opinions in Hematology; WedMD/Medscape: Membership on an entity's Board of Directors or advisory committees; National Institutes of Health: Research Funding; University of Washington: Employment, Research Funding; American College of Physicians: Other: Editor and author; GlaxoSmithKline: Equity Ownership; Johnson&Johnson: Equity Ownership; Cellerant: Membership on an entity's Board of Directors or advisory committees; Sanofi Aventis: Consultancy, Editor, Current Opinions in Hematology, Honoraria; Amgen: Consultancy, Research Funding.

Frequency and Functional Analysis of Myeloid-Derived Suppressor Cells (MDSCs) in the Peripheral Blood and Bone Marrow of Patients with Chronic Idiopathic Neutropenia (CIN)

Myeloid-derived suppressor cells (MDSCs) are myeloid cells with immunoregulatory properties characterized mainly by suppression of T-cell responses (Bizymi et al, HemaSphere 2019). They are divided in HLA-DRlow/-/CD11b+/CD33+/CD15+ polymorphonuclear (PMN-MDSCs) and HLA-DRlow/-/CD11b+/CD33+/CD14+ monocytic (M-MDSCs) subsets and they are implicated in inflammatory and malignant diseases. Chronic idiopathic neutropenia (CIN), is a (usually benign) neutrophil disorder characterized by persistent and unexplained neutropenia following a detailed clinical/laboratory investigation including anti-neutrophil antibody testing, bone marrow (BM) biopsy and karyotype (Dale &amp; Bolyard, Curr Opin Hematol 2017). Previous studies have shown that neutropenia in CIN is associated with increased apoptosis of BM granulocytic progenitor cells due to an inflammatory BM microenvironment consisting of oligoclonal T-lymphocytes, proinflammatory monocytes and proapoptotic cytokines. The aim of the present study is to explore the possible involvement of the MDSCs in the pathophysiology of CIN by investigating their number in peripheral blood (PB) and BM in association with their functional characteristics. We have studied 100 CIN patients and 49 age- and sex-matched healthy controls. The patients fulfilled the previously described diagnostic criteria for CIN (Papadaki et al, Blood 2003) and had mean neutrophil counts 1095.67 ± 479.52 (median 1215, range 100-1700). MDSC subsets were quantitated by flow cytometry in the PB mononuclear cell (PBMC) fraction using the combination of CD33PC7/CD15PC5/HLA-DRECD/CD14PE/CD11bFITC monoclonal antibodies and the Kaluza analysis software. MDSC subsets were also studied in the BMMC fraction of 24 CIN patients and 8 healthy controls from the study population. The T-cell suppression function of patient MDSCs was evaluated in coculture experiments of immunomagnetically sorted, CFSE stained, normal CD3+ cells with immunomagnetically sorted M-MDSCs and PMN-MDSCs from 4 patients and 4 healthy donors using recombinant human IL-2 as activating factor. CFSE staining was detected in the CD3+ cells on day 0 and day 3 of coculture and analysis was performed with the Fcs Express 7 software. Statistical analysis was performed with the Statistica software. We found that the proportion of PB M-MDSCs was statistically significant lower in CIN patients (1.45% ± 1.82%) compared to controls (3.68% ± 3.12%, Mann-Whitney test, p &amp;lt; 0.0001) (Figure a) whereas the proportion of PB PMN-MDSCs, although lower in patients, did not differ significantly from the controls. The proportion of BM M-MDSCs did not differ significantly between CIN patients and controls whereas the proportion of BM PMN-MDSCs was statistically significant lower in patients (13.27% ± 11.27%) compared to controls (19.49% ± 4.46%; Mann-Whitney test, p = 0.0291) (Figure b). Paired analysis showed that the proportion of PMN-MDSCs were higher in the BMMC compared to PBMC fraction in both CIN patients (13.27% ± 11.27% vs 1.14% ± 1.64%, respectively; Wilcoxon test, p = 0.005) (Figure c) and healthy controls (19.49% ± 4.46% vs 9.92% ± 9.08%, respectively; Wilcoxon test, p = 0.0118). Interestingly, the proportion of increase of PMN-MDSCs (in BMMC vs PBMC fraction) was significantly higher in patients (86.71% ± 21.26%) compared to controls (55.95% ± 38.59%; Mann-Whitney test, p = 0.0357) (Figure d). The above data indicate low production of PMN-MDSCs in CIN patients compared to controls but a trend for accumulation of these cells in patients' BM. No statistically significant difference was documented in paired analysis of M-MDSCs between BMMC and PBMC fractions in either CIN patients or healthy controls. Patient PMN-MDSCs and M-MDSCs displayed normal capacity to suppress T-cell proliferation as was indicated by the T-cell generations in coculture experiments of normal CD3+ cells in the presence or absence of patient MDSCs (Figure e). In conclusion, CIN patients display low proportion of MDSCs in the PB and lower proportion of PMN-MDSC in the BM compared to normal individuals. Patient MDSCs display normal capacity to suppress T-cell activation. The low proportions of MDSCs may sustain the inflammatory process associated with CIN whereas the accumulation of PMN-MDSCs in the BM represents probably a compensatory mechanism to suppress the inflammatory processes within patients' BM microenvironment. Figure Disclosures Papadaki: Genesis pharma SA: Membership on an entity's Board of Directors or advisory committees, Research Funding.

Autoimmune hemolytic anemia, autoimmune neutropenia and aplastic anemia in the elderly

The physiology of the immune system involves morphologic and functional changes occurring along ageing, with a decrease in immune response and an increase in autoimmune phenomena, even in the absence of overt disese. Autoimmune cytopenias, namely autoimmune hemolytic anemia (AIHA), chronic idiopathic neutropenia (CIN) and aplastic anemia (AA), show different epidemiologic predilection, but are increasingly diagnosed in the elderly, where complications and comorbidities are more frequent. A systematic review of recent literature, shows that comorbidities as well as underlying deficiencies, medications, neoplasms, and, pathophysiologic chronic organ failures, frequently challenge the differential diagnosis in this setting and should always be evaluated and excluded. Complications, particularly infections and thrombosis for AIHA, and bleeding for AA, should be monitored and promptly treated. Treatment choice should be carefully weighed on the individual general condition and comorbidities, granted that intense primary care and support (including evidence-based transfusion policies) are provided. Finally, bone marrow histology is highly advisable in the elderly, both at diagnosis to detect underlying conditions, and along the follow-up to monitor possible bone marrow failure or neoplastic evolution.

Reference guide for adult chronic neutropenia

Chronic neutropenia is a rare hematological entity characterized by isolated neutropenia without anemia or thrombocytopenia. The diagnostic criteria and classification of chronic neutropenia have been more elusive in adult cases than pediatric cases. We herein propose the Reference Guide for Adult Chronic Neutropenia. In this guide, diagnosis of chronic neutropenia is based on recurrent or continuous neutropenia defined by absolute neutrophil count (ANC) less than 1,500/µl for over three or more months. Severity of chronic neutropenia is defined as follows: severe, ANC <500/µl; moderate, ANC between 500 and 1,000/µl; mild, ANC between 1,000 and 1,500/µl. In this guide, adult chronic neutropenia is classified into several types including autoimmune neutropenia, cyclic neutropenia, chronic neutropenia with T cell clone, and chronic idiopathic neutropenia with or without family history, and their clinical characteristics are described. Together with antibiotics, granulocyte colony-stimulating factors (G-CSFs) constitute the first-line treatment for adult chronic neutropenia patients at time of bacterial infections. Prophylactic use of G-CSFs or antibiotics is recommended only in selected clinical settings in severe cases.

Immunoglobulin and B-cell disturbances in patients with chronic idiopathic neutropenia

Chronic idiopathic neutropenia (CIN) is a granulocytic disorder associated with presence of activated, myelosuppressive T-lymphocytes. In the present study we have evaluated constituents of humoral immunity in CIN patients (n=48) compared to healthy controls (n=52). CIN patients displayed lower serum IgG levels due to a reduction in IgG1, IgG3, IgG4 but not IgG2, lower IgA and increased IgM levels compared to controls. The proportion of CD19+ cells did not differ between patients and controls; however the proportion of the naïve IgD+/CD27− B-cells was increased and the proportion of class-switched memory IgD−/CD27+ B-cells was decreased in the patients. The percentage of CD40+ B-cells did not differ between patients and controls and no aberrations in the CD40-meadiated signal transduction pathway or in CD40-gene polymorphisms were identified. These data provide further evidence that immune disturbances are associated with the pathophysiology of CIN and point out for the first time the implication of the B-cell system.

An update on the diagnosis and treatment of chronic idiopathic neutropenia.

Neutropenia lasting for at least for 3 months and not attributable to drugs or a specific genetic, infectious, inflammatory, autoimmune or malignant cause is called chronic idiopathic neutropenia (CIN). CIN and autoimmune neutropenia (AIN) are very similar and overlapping conditions. The clinical consequences depend upon the severity of neutropenia, but it is not considered a premalignant condition. Long-term observational studies in children indicate that the disease often lasts for 3-5 years in children, then spontaneously remits, but it rarely remits in adult cases. The value of antineutrophil antibody testing in both children and adults is uncertain. Most recent data suggest that CIN and AIN are immune-mediated diseases, but there are no new clinical or genetic tests to aid in diagnosis. Treatment with granulocyte colony stimulating factor (G-CSF) is effective to increase blood neutrophils in almost all cases; this treatment is reserved, however, for patients with both neutropenia and evidence of recurrent fevers, inflammatory symptoms and infections. There is little or no evidence to indicate that G-CSF treatment predisposes to myeloid malignancies in this population. It is important to recognize CIN and AIN, the most common causes of chronic neutropenia in both children and adults. If the neutropenia is not severe, that is more than 0.5 × 10/l, most patients can be observed and not treated prophylactically with antibiotics or a growth factor. When neutropenia is severe, treatment with G-CSF is often beneficial.

Minor populations of paroxysmal nocturnal hemoglobinuria-type cells in patients with chronic idiopathic neutropenia.

Chronic idiopathic neutropenia (CIN) is an acquired disorder of granulopoiesis characterized by increased apoptosis of the bone marrow (BM) granulocytic progenitor cells under the influence of pro-inflammatory mediators and oligoclonal/monoclonal T-lymphocytes. Because patients with immune-mediated BM failure display frequently paroxysmal nocturnal hemoglobinuria (PNH)-type cells in the peripheral blood (PB), we investigated the possible existence of PNH-type cells in 91 patients with CIN using flow cytometry. The patients displayed increased proportions of PNH-type glycophorin A+ /CD59dim and glycophorin A+ /CD59- red blood cells (RBCs), FLAER- /CD24- granulocytes, and FLAER- /CD14- monocytes, compared to controls (n = 55). A positive correlation was found between the proportions of PNH-type RBCs, granulocytes, and monocytes and an inverse correlation between the number of PB neutrophils and the proportions of PNH-type cell populations. The number of patients, displaying percentages of PNH-type cells above the highest percentage observed in the control group, was significantly increased among patients with skewed compared to those with normal T-cell receptor repertoire suggesting that T-cell-mediated immune processes underlie the emergence of PNH-type cells in CIN. Our findings suggest that patients with CIN display PNH-type cells in the PB at a high frequency corroborating the hypothesis that CIN belongs to the immune-mediated BM failure syndromes.

Reduced 25-OH vitamin D in patients with autoimmune cytopenias, clinical correlations and literature review.

Vitamin D deficiency is widespread in Western Countries and has been found related to autoimmune and hematologic disease incidence and clinical course. We evaluated vitamin D levels, vitamin D receptor (VDR) and T helper (Th)1, Th2 and Th17 immunomodulatory cytokines in patients with immune thrombocytopenic purpura (ITP, N=44), primary autoimmune hemolytic anemia (AIHA, n=35), Evans' syndrome (n=5) and chronic idiopathic neutropenia (CIN, n=19) and also tested vitamin D effect on the in vitro production of anti-erythrocyte autoantibodies. 25-OH-vitamin D levels were significantly lower and vitamin D receptor higher in patients than in controls. Among ITP cases, those with very low vitamin D levels displayed reduced platelet counts, irrespective of the bleeding history. In AIHA patients, LDH values negatively correlated with vitamin D levels in mixed forms, and reticulocyte counts were positively related with vitamin D. Considering treatment, AIHA patients who had been treated with 2 therapy lines or more showed lower mean 25-OH-vitamin D levels than those untreated or treated with one line of therapy only. IL-6, IL-10, IL-17 and IFN-γ levels were higher in patients versus controls, whereas TNF-α was significantly reduced. Finally, vitamin D at concentrations of 10, 20, and 40ng/mL reduced the in vitro production of anti-erythrocyte autoantibodies both in pokeweed-stimulated and unstimulated cultures. In conclusion, vitamin D is reduced in autoimmune cytopenias and correlate with disease severity, supporting its possible protective role against the development of autoimmunity. Literature review showed vitamin D deficiency reports both in onco- and in non onco-hematologic diseases with a relationship with disease severity/activity in myeloid and lymphoid neoplasms, as well as in sickle cell disease. Supplementation has produced weak results in autoimmune and hematologic diseases, and further studies are needed.

Increased Frequency of Paroxysmal Nocturmal Hemoglobinuria Type Cells in Patients with Chronic Idiopathic Neutropenia Correlates with the Severity of the Disease and the Presence of Skewed T-Cell Expansions

Introduction: Chronic idiopathic neutropenia (CIN) of adults is an acquired disorder of granulopoiesis characterized by an unexplained, prolonged reduction in the number of peripheral blood (PB) neutrophils. We have previously shown that CIN pathophysiology is related to T-cell activation and increased apoptosis of granulocytic progenitor cells. Notably, in our cohort of patients we exclude cases with antineutrophil antibody activity, i.e. autoimmune neutropenia cases.Aim of the study: Preliminary data have shown the presence of minor populations of paroxysmal nocturmal hemoglobinuria (PNH) type cells in the PB of CIN patients. The present study aims to investigate further the presence of PNH type cells in the PB of a large cohort of patients fulfilling the diagnostic criteria of CIN and probe the possible association with the severity of the disease and the skewed T-cell profile.Patients - Methods: We have studied 91 adults with CIN and 55 hematologically healthy subjects, age- and sex-matched with the patients. We have used flow cytometry for the detection of PNH type cells according to the International Clinical Cytometry Society guidelines and for the identification of T-cell expansions based on the analysis of T-cell receptor beta variable (TRBV) gene repertoire.Results: CIN patients displayed increased proportion of PB PNH type FLAER-/CD24- neutrophils (0.05% ± 0.18%) and FLAER-/CD14- monocytes (1.33% ± 1.38%) compared to healthy individuals (0.005% ± 0.01% and 0.64% ± 0.66%, respectively; P =0.0044 and P =0.011, respectively). Similarly, the patients displayed increased proportion of both, type II CD235+/CD59dim and type III CD235+/CD59- (0.059% ± 0.29% and 0.065% ± 0.28%, respectively) PB PNH red blood cells, compared to healthy controls (0.01% ± 0.03% and 0.01% ± 0.03%, respectively; P<0.0001 and P< 0.0001, respectively). Interestingly, an inverse correlation was found between the proportion of PB PNH type neutrophils and the number of absolutely neutrophil counts in CIN patients (r=-0.2525, P =0.0157) whereas no correlation was found between the proportion of PNH red blood cells or monocytes and absolutely neutrophil counts. In accordance with our previously reported data, increased frequency of skewed T-cell expansions were identified in CIN patients (71.4%) compared to healthy subjects (29.9%; P<0.0001). PNH type neutrophils (FLAER-/CD24-) were identified at a higher frequency in patients with skewed TRBV repertoire (63.08%) compared to those with normal TRBV distribution (34.61%) (P = 0.0194) suggesting a possible pathogenetic/pathophysiologic association between T-cell activation and emergence of PNH neutrophils in CIN.Conclusion: CIN patients display minor populations of PNH type PB neutrophils, monocytes and red blood cells. The frequency of PNH type neutrophils is associated with the severity of neutropenia and it is higher among patients with skewed TRBV repertoire. These data support further the hypothesis that CIN displays common pathophysiologic features with immune-mediated bone marrow failure syndromes and should be included in this spectrum of disease entities. DisclosuresPapadaki:Alexion Pharmaceuticals: Research Funding.

Is chronic neutropenia always a benign disease? Evidences from a 5-year prospective study

AimTo evaluate infections and oncohematologic evolution in adult patients with chronic idiopathic and autoimmune neutropenia in a prospective study. Patients and methods76 consecutive patients were enrolled from September 2008 to April 2012. Complete blood counts and clinical evaluation were performed at enrolment, at month 3, 6, and then every 6months. Anti-neutrophil antibodies were tested by GIFT method. ResultsPatients (49 chronic idiopathic- and 27 autoimmune neutropenia) were followed for a median of 5years (range 24–84months). At enrolment, neutropenia was mild in 44 patients (median neutrophils 1.27×103/μL), moderate in 23 (median 0.8×103/μL), and severe in 9 (median 0.4×103/μL). Neutrophil counts showed a great inter-subject but no intra-subject variability, with lower values in autoimmune neutropenia, in males, and in MGUS cases. Over time, no grade >3 infections occurred; 13/49 chronic idiopathic and 6/27 autoimmune neutropenia patients experienced a grade 2 event, irrespective of mean and nadir neutrophil values. Bone marrow evaluation at enrolment showed reduced cellularity in 23% of cases, and dyserythropoietic features in 55%, with no definite hematologic diagnosis. During the follow-up, 5 cases were diagnosed with NK expansion, 4 with hairy cell leukemia, and 3 with myelodysplasia (1 myelomonocytic leukemia, 1 refractory cytopenia with unilineage dysplasia, and 1 multilineage dysplasia), with a median time to evolution of 30months. ConclusionChronic idiopathic and autoimmune neutropenia, although usually benign, deserve hematological follow-up with a bone marrow evaluation at diagnosis and a re-evaluation in the presence of worsening neutropenia, appearance of additional cytopenias, and lymphocytosis.

High-Throughput Profiling of the T-Cell Receptor Gene Repertoire Supports Antigen Drive in the Pathogenesis of Chronic Idiopathic Neutropenia

Chronic idiopathic neutropenia (CIN) is an acquired disorder of granulopoiesis characterized by prolonged neutropenia, mainly affecting middle-age females of the HLA-DRB1*1302 type. The defective hematopoiesis in CIN can be mainly attributed to accelerated Fas-mediated death of the CD34+/CD33+ granulocytic progenitors, secondary to an inflammatory bone marrow (BM) microenvironment. Crucial to CIN pathogenesis are the increased numbers of activated T cells identified in both peripheral blood (PB) and BM of CIN patients, supporting an immune pathogenesis. Using Sanger sequencing, we previously reported that the T-cell receptor (TR) gene repertoire in CIN is skewed, indicating antigen selection in CIN ontogeny. However, the analytical depth afforded by Sanger sequencing is limited, hindering definitive conclusions. In order to obtain a truly comprehensive view into the role of antigen drive in CIN, using next generation sequencing (NGS) we interrogated the TR repertoire of 13 patients (8 females, 5 males) included in our previous study as well as a healthy female. TRBV-TRBD-TRBJ gene rearrangements were amplified according to the BIOMED2 protocol on either genomic DNA or cDNA isolated from CD8+ cells of PB (n=4) or BM (n=10) samples. PCR products were used as a substrate for paired-end sample preparation (Illumina) and subjected to NGS on the MiSeq Illumina Platform. The raw NGS data were preprocessed with a dedicated pipeline for this purpose, including: (i) quality filtering of each read; (ii) merging of paired-end reads via local alignment; (iii) preparation of fasta files for submission to the IMGT/High V-QUEST tool; and, (iv) IMGT/High V-QUEST metadata analysis, interpretation and visualization. Overall, 6,196,980 TRBV-TRBD-TRBJ gene rearrangements were analyzed (130,020-1,037,680 /case) of which 5,317,609 were productive since they used functional TRBV genes and also carried in-frame CDR3. Rearrangements with identical TRBV gene usage and CDR3 sequence were defined as clonotypes. For repertoire analyses, clonotypes rather than single rearrangement sequences were considered. Overall, 553,145 unique clonotypes were identified (median 39,510; range 7,732-172,253/case), of which 408,744 represented singletons. All clonotypes from the Sanger analysis were detected by NGS as well. Among the 46 functional TRBV genes identified, the most frequent were: TRBV29-1 (13.9%), TRBV19 (6.7%), TRBV12-3 (5.6%), TRBV6-5 (5.4%), TRBV27 (4.9%) and TRBV6-1 (4.0%), collectively accounting for 40,5% of the TRBV repertoire; the TRBV29-1 gene predominated in 9/13 CIN cases. All CIN cases were found to carry distinct expanded clonotypes (median 10,314; range 2,279-40,245/case). The predominant clonotype ranged in frequency from 5.25 to 20.2% of the total clonotypes observed in each case. This contrasts significantly (p<0.001) with a 0.47% frequency of the dominant clonotype in the healthy control. Cluster analysis of the sequences of all CIN cases identified 9034 different clonotypes shared by different patients and, thus, deemed as public. Notably, public clonotypes of a given CDR3 length could show high sequence similarity, further underscoring the restricted nature of the repertoire. As an example, 1632/2665 (61.2%) public clonotypes with 12 aminoacid-long CDR3 were grouped into 168 distinct communities, populated with 2-280 highly similar sequences, each linked with 1 aminoacid distance with at least another member of the community. Overall, the present study offers conclusive evidence that the TR repertoire in CIN is remarkably skewed. The finding of oligoclonal T-cell expansions and public clonotypes strongly indicates that antigen-driven immune responses are very likely implicated in the pathogenesis of CIN. DisclosuresNo relevant conflicts of interest to declare.

25-Oh Vitamin D, Vitamin D Receptor and Immunomodulatory Cytokines Serum Levels in Patients with Autoimmune Citopenias: Correlation with Hematologic Parameters and Clinical Severity

Increasing evidence is being produced about the immunomodulatory role of 25-OH vitamin D on Th1/Th2 balance, T-reg activation and cytokine production in autoimmune diseases. We evaluated vitamin D levels and its receptor (VDR), as well as immunomodulatory cytokines in patients with primary immune thrombocytopenia (ITP), autoimmune hemolytic anemia (AIHA), Evans’ syndrome (ES), and chronic idiopathic neutropenia (CIN). We enrolled 103 patients, median age 59 years (range 17-86), 32 males and 71 females; clinical history, physical examination, complete blood count, serum samples and informed consent were collected at the time of enrolment. The number of immunosuppressive therapy lines (steroids, immunosuppressors, rituximab, splenectomy, and thrombopoietin agonists for ITP) were retrospectively collected. 25-OH vitamin D, VDR, and immunomodulatory cytokines levels were evaluated in serum from all patients and 40 age and sex matched healthy controls, using ELISA kits. Statistical analysis was performed using Student’s t test for continuous variables and chi-square test for categorical variables. Hematologic parameters, vitamin D, VDR and cytokine levels of 44 ITP patients, 35 AIHA, 19 CIN, and 5 Evans syndrome are shown in Table. 25-OH vitamin D levels were significantly lower (2.3±1.8 vs 6±6 ng/mL, mean±SD, p<0.001) and VDR significantly higher (mean 26.5±0.9 versus 20,9±1.0 pg/mL; p>0.001) in patients than in controls, regardless sex, age and type of cytopenia (Table). No relationship was found among vitamin D levels and hemoglobin, platelets and ANCs values at enrollment for AIHA, ITP and CIN patients. Likewise VDR levels were not associated with hematological parameters. However, 20 ITP with very low vitamin D levels (<1.3 ng/mL, lower limit of controls) displayed reduced platelets counts compared with the remaining 24 (74±42 x103/mL versus 114±89, p=0.04), irrespective of the bleeding history (positive in 31 patients). As regards cytokines levels (Table), the following differences were found versus controls: IL-6, IL-10 and IL-17 serum levels were higher in AIHA and ITP, significantly for the former two cytokines; IFN-g was increased in all hematologic cytopenias, significantly in CIN. Finally, TNF-a was significantly reduced in AIHA, ITP and CIN patients versus controls. Cytokine levels showed no relationship with vitamin D and VDR levels, nor with the hematologic parameters. However, AIHA cases with Hb <10g/dL at enrollment displayed increased IL-17 levels, although not significantly. Moreover CIN cases with ANCs<1x103/mcL showed higher IL-6 and lower TNF-a compared to those with higher ANCs. Among ITP patients, those with platelets <100.000/mcL showed reduced values of IL-6 and IFN-g.As regards therapy, 90% of ITP and AIHA, and all ES cases were treated with steroids. Rituximab was administered in 1 ITP, 17 AEA, and 2 ES, and immunosuppressors in 7, 6 and 4 cases, respectively. Splenectomy was performed in 8 ITP, 2 AEA and 2 ES, and TPO-agonists used in 5 ITP and 1 ES. CIN patients received no specific treatment. Considering the number of therapy lines vitamin D levels were reduced in AIHA patients who underwent two or more lines compared to cases with 0 or 1 line of therapy (1.7±1 ng/mL vs 2.8±1.8 ng/mL, p=0.04). No association was found among the number of therapy lines and VDR and cytokines levels in ITP and AIHA cases.In conclusion, we report evidence of reduced values of vitamin D in autoimmune cytopenias, particularly in AIHA cases refractory to first line therapy, and in CIN patients with more marked neutropenia. Moreover VDR was increased in all disease investigated, suggesting a compensatory up-regulation and/or an increased shedding possibly related to a reduced receptor engagement. We also observed and over-expression of Th1 and Th2 cytokines, consistent with the role of autoimmune activation in hematologic cytopenias. Likewise, IL-17 which is produced by a novel Th cell subset distinct from Th1 and Th2 cells was found increased in our cases, in line with what reported in various autoimmune diseases, although without a definite relationship with clinical and hematologic parameters and vitamin D levels or its receptor. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Familial CD3+ T large granular lymphocyte leukemia: evidence that genetic predisposition and antigen selection promote clonal cytotoxic T-cell responses

CD3+ T-large granular lymphocyte (T-LGL) proliferations often present with cytopenias and splenomegaly and are linked to autoimmunity, especially rheumatoid arthritis and Felty's syndrome. We report here the intra-family occurrence of T-LGL leukemia in a father and son, both presenting with cytopenias and splenomegaly. Both patients carried the HLA-DRB1*04 allele, strongly associated with rheumatoid arthritis and Felty's syndrome, exhibited distinctive histopathological features suggestive of immune-mediated suppression of hematopoiesis and expressed a remarkably skewed T-cell receptor beta chain gene repertoire with overtime evolution (clonal drift). Immunoinformatics analysis and comparisons with clonotype sequences from various entities revealed (quasi)identities between (i) father and son, and (ii) father or son and patients with autoimmune disorders, T-LGL leukemia or chronic idiopathic neutropenia. Altogether, our results further corroborate antigen selection in the ontogeny of T-LGL leukemia and point to the interplay between genetics and the (micro)environment in shaping the outcome of cytotoxic T cell responses.

Unexplained chronic leukopenia treated with oral iron supplements

Case A 67-year-old woman known to have iron deficiency anemia and persistent unexplained chronic leukopenia was cared for by our medical center for about 16 years. During this period she was examined thoroughly and diagnosed to have chronic idiopathic neutropenia (also known as chronic benign neutropenia). Her iron deficiency was attributed to nutritional factors and she was non-compliant with her oral iron supplements. The patient fully received her iron supplement medication by nursing staff for two and a half months during an unexpected prolonged hospital stay after her suffering an acute ischemic cerebrovascular accident. An astonishing outcome was that in addition to having her iron deficiency anemia treated, her long-term unexplained neutropenia was also corrected. Conclusion Some patients diagnosed with chronic idiopathic neutropenia and clinically present as having unexplained chronic neutropenia might actually be suffering from a form of not yet described iron deficiency induced neutropenia.

Etiology, clinical outcome, and laboratory features in children with neutropenia: Analysis of 104 cases

Neutropenia is not uncommon in childhood. The aim of our study was to analyze the underlying causes of neutropenia and to evaluate its clinical significance in a series of children referred to our center. One hundred and four consecutive children with neutropenia were enrolled in this study. Clinical and laboratory features were analyzed. The majority of patients (63.5%) showed chronic neutropenia. Among all chronic forms, the most frequent was chronic idiopathic neutropenia (CIN), followed by autoimmune neutropenia (AIN). Congenital neutropenia was identified in 6 patients. Acute neutropenia was mainly due to infections. Overall, at the time of first detection, neutropenia was more frequently severe or moderate. One-third of our patients who presented with severe neutropenia were ultimately diagnosed with a post-infectious acute form. Conversely, nearly half patients with CIN, AIN, or congenital neutropenia showed moderate/mild neutropenia at onset. Among patients with AIN and CIN, nearly half recovered between 7 months and 46 months and approximately one-fourth experienced infectious episodes during follow-up. No significant difference was noticed in terms of mean ANC between patients with and without remission, neither between patients with and without infections. Our study confirms the great etiological heterogeneity of neutropenia in children. We could not demonstrate a correlation between ANC level at onset and the underlying disorder, nor a correlation between mean ANC and duration of neutropenia or infectious episodes during follow-up. Neutropenia remains a disease of concern to pediatricians, requiring several laboratory investigations, prolonged follow-up, and, in few cases, advanced molecular methods.

Chronic Idiopathic Neutropenia In Adults: Clinical Features In a 4-Year Prospective Study

Chronic idiopathic neutropenia (CIN) is a rare acquired hematological condition, defined by an absolute neutrophil count (ANCs) lower than 1.8 x103/µL in white and 1.5 x103/µL in black people for more than 3 months, either in the absence or in the presence of anti-neutrophils antibodies (autoimmune forms). CIN is usually diagnosed after the exclusion of congenital and secondary forms. The former are usually marked by frequent and severe infections, that occur early in life, and by and increased risk of evolution to acute myeloid leukemia or myelodisplastic syndromes. In this prospective study we followed up 56 patients with CIN (21 males and 35 females, median age 55 years, range 25-86 years) for a median time of 48 months from January 2009 (10 patients had a previous follow-up of 8 years and 2 of 10 years), focusing on 1) severity of neutropenia, 2) ANCs variations (by general estimating equations GEE models), 3) positivity for anti-neutrophil antibodies (by direct and indirect granulocyte immunofluorescence test), 4) bone marrow features, 5) incidence of infectious episodes, and 6) evolution to definite clonal hematologic diseases (hairy cell leukemia HCL, chronic expansion of NK cells and myelodisplastic syndrome MDS). The mean ANCs were stably under the normal range (1.5-6.5 x103/µL) at all the time points considered; by GEE analysis, a great inter-subject variability was observed during the follow-up (p=0.012), whereas no significant intra-subject variations were found. Considering the severity of neutropenia, 21 patients (47%) showed neutrophils lower than 1x103/µL at enrollment (median 0.49 x103/µL, range 0.1-0.969 x103/µL), and 8 cases <0.5 x103/µL. The mean ANCs observed during the follow up were significantly lower in males than in females (p=0.023) and in cases with mild splenomegaly, although not significantly (11 cases, 20%, mean maximal diameter 11,4 cm by ultrasonography), independently from gender (multivariate analysis). Anti-neutrophil antibodies were detected in 19/56 patients (34%), and mean ANCs values over the follow up were significantly lower in positive versus negative cases (p=0.027). Lymphocyte values greater than the upper normal value of our series (3.4 x103/µL) were observed in 5/56 patients (9%). By peripheral blood immunophenotyping (N=23), 13 (56.5%) patients displayed absolute NK+ cells greater than 0.2 x103/mL (normal NK cut-off value), but all under below 2 x103/µL. Bone marrow evaluation was performed in 27 patients: median cellularity was 35% (range 13-75), and 10/27 (37%) displayed a value lower than 25% (threshold for hypocellularity in aplastic anemia); 19/27 (70%) showed some dysplastic cells, even if less than 10% dysplastic cells and without coexistent MDS-related karyotype; cytogenetic was normal in 24 cases (89%), while 3 males, all older than 60 years, displayed a 45, X0 karyotype (7, 6 and 3 metaphases respectively. Finally, 10 patients (18%) showed monocytosis, and 6 (10%) a MGUS. An infection needing oral antibiotic or antiviral therapy occurred in 13 patients (25%) (2 pneumonias, 7 upper respiratory tract, 3 Herpes Zoster Virus and 1 urinary tract infections), without relationship with the patient's mean ANCs value, the nadir of ANC value, nor with the presence of anti-neutrophil antibodies. During the follow-up, because of suspected progression/evolution, 14 patients were re-evaluated by bone marrow biopsy or peripheral immune-phenotyping: 4 cases were diagnosed with chronic NK expansion, 4 with HCL, and 2 with MDS, one refractory cytopenia with unilineage dysplasia (RCUD) and one with multilineage dysplasia (RCMD). No association was found between evolution and ANCs, both as values at enrolment and mean counts over the follow up, nor with gender, presence of anti-neutrophils antibodies, monocytosis, splenomegaly, electrophoresis abnormalities and infections. All 4 patients, who developed an NK-expansion, showed peripheral lymphocytes >3.4 x103/µL at enrolment (>5x103/µL in only 1 case), and 3 cases displayed increased NK cells at peripheral immune-phenotyping (p= 0.018). In conclusion, CIN in adults is a benign disease, with an infectious rate not superior to that of the general population and a great variability in ANCs values. During this prospective observation, 10 CIN patients evolved, reaching the criteria for clonal hematological diseases, suggesting that this condition deserves clinical follow up. Disclosures:No relevant conflicts of interest to declare.

Association between helicobacter pylori infection and chronic idiopathic neutropenia

The possible association between Helicobacter pylori (H. pylori) infection and chronic idiopathic neutropenia (CIN) was investigated. A total of 78 subjects with CIN were recruited in this case-control study. As a control group, 40 subjects without CIN were selected for comparison with the case group. All participants were evaluated for the prevalence of H. pylori infection by 14C-urea breath test. The corrected splenic index (CSI) was calculated, and serum IL-6, IL-8, IL-10 and HsCRP levels were measured. The differences in CSI, serum IL-6, IL-8, IL-10 and HsCRP levels were compared between CIN patients and controls, as well as between subjects with and without H. pylori infection. The positive rate of H. pylori was 87.18% in CIN group and 52.50% in control group, showing a significant difference (Fisher's exact, P=0.000). CSI values, and serum IL-6 and HsCRP levels in H. pylori positive-CIN patients were significantly higher than those in negative subjects (Mann-whitney U-test, P=0.016, P=0.001 and P=0.000 respectively), while IL-10 level declined significantly in H. pylori negative-CIN patients (Mann-whitney U-test, P=0.000). In control group, serum IL-6 and HsCRP levels in H. pylori positive individuals were also increased significantly (Mann-whitney U-test, P=0.000), while IL-10 level declined (Mann-whitney U-test, P=0.018). Multivariate regression analysis revealed that H. pylori infection and IL-10 were significant risk factors for CIN with odds ratio (OR): 3.09, 95.0% CI: 1.22-6.93; P=0.019, and OR: 0.17, 95.0% CI: 0.05-0.94; P=0.021, respectively. This prospective study confirmed the existence of an association between H. pylori infection and CIN, suggesting the screening for H. pylori infection and eradicating bacterium in positive cases seem appropriate and beneficial for those patients with CIN diagnosis.

Mesenchymal Stem Cells in Immune-Mediated Bone Marrow Failure Syndromes

Immune-mediated bone marrow failure syndromes (BMFS) are characterized by ineffective marrow haemopoiesis and subsequent peripheral cytopenias. Ineffective haemopoiesis is the result of a complex marrow deregulation including genetic, epigenetic, and immune-mediated alterations in haemopoietic stem/progenitor cells, as well as abnormal haemopoietic-to-stromal cell interactions, with abnormal release of haemopoietic growth factors, chemokines, and inhibitors. Mesenchymal stem/stromal cells (MSCs) and their progeny (i.e., osteoblasts, adipocytes, and reticular cells) are considered as key cellular components of the bone marrow haemopoietic niche. MSCs may interfere with haemopoietic as well as immune regulation. Evidence suggests that bone marrow MSCs may be involved in immune-mediated BMFS underlying pathophysiology, harboring either native abnormalities and/or secondary defects, caused by exposure to activated marrow components. This review summarizes previous as well as more recent information related to the biologic/functional characteristics of bone marrow MSCs in myelodysplastic syndromes, acquired aplastic anemia, and chronic idiopathic neutropenia.

Hesk Ratio: A Complementary Tool for the Diagnosis of Myelodysplastic Syndromes and a Novel Method for Flow Cytometry Analysis

AbstractAbstract 4946Establishing the diagnosis of Myelodysplastic Syndromes (MDS) is a challenging task for hematologists due to the heterogeneity of this clinical entity. Several attempts have been made to include findings from advanced technologies to the diagnostic criteria of MDS, but still in the majority of cases, morphology of peripheral blood and bone marrow remains the cornerstone for the diagnosis. Flow cytometry(FC) can identify abnormal antigen expression on myeloid cells. FC has been proposed as a complementary method in the diagnosis of low and intermediate risk MDS, particularly for patients not exhibiting characteristic karyotype abnormalities. On the other hand, recent literature suggests that these findings are not MDS-related, questioning the specificity of immunophenotyping for the diagnosis of MDS.The aim of the present study is to maximize the utility of FC data and simplify their interpretation for the diagnosis of MDS, by developing new analytical approaches of digital data, other than the conventional sequential biparametric analysis. The applied methodology was based on a mathematical model of scale analysis.Bone marrow(BM) samples from 50 subjects were analysed for the expression of CD45PC7, CD11bPC5, CD16FITC and CD13PE (antigens by Beckman Coulter, FC500 flow cytometer Beckman Coulter). 36 patients were diagnosed with MDS (23 low risk, 13 high risk) and 14 patients had other than an MDS diagnosis (ITP, chronic idiopathic neutropenia, systemic lupus erythematosus, LGL leukemia, age-related cytopenias, aplastic anemia, myelofibrosis etc). Additionally, 3 BM samples of patients with post-MDS acute myeloid leukemia(AML) were analysed. 1.The data used for the development of the mathematical model were the following: two populations (neutro1, neutron2) were gated according to their CD45 and CD13/CD16 antigen expression (Figure 1i-1v).2.Seven subpopulations of Neutrophils were defined on CD11b/CD16 density plot N=g+h+i and O=k+j (Figure 1vi).In an attempt to identify correlations between data that cannot be routinely revealed by sequential biparametric analysis, we have developed the HeSK* ratio, which is given by: [Display omitted] where x is the median of CD11b in gate O, y is the median of CD16 in gate O, z is the median of CD45 in gate neutro, pO is the percentage of gate O in the total CD11b/CD16 diagram gated in neutro, pN is the percentage of gate N in the total CD11b/CD16 gated in neutro and 1000 is an empirical parameter.The HeSK ratio combines fluorescence levels of CD16, CD11b and CD45 with the percentage of two distinct neutrophil populations (N and O), which differ in their maturation and differentiation stage. The ratio can quantify the abnormal differentiation profile of mature myeloid cells and thus distinguish MDS from non-MDS samples with statistical significance P<0. 0001 (Kruskal Wallis test) as indicated in graph 1. Descriptive statistics are shown in table 1.· HeSK ratio is based upon a novel FC analysis method that could change the conventional biparametric routine FC analysis and quantify patterns that are not evaluated properly. Mathematical modeling of antigen expression patterns optimizes the interpretation of single immunophenotype findings.· The present study proposes HeSK as a complementary diagnostic tool for MDS and a strong indicator for the classification of the patients according to their prognosis as well.*the name HeSK comes from the initials of the 4 main authors (H=Hala, e=Evgenia, S=Smirni, K=Kolliopoulou).Table 1non MDSlow risk MDShigh risk MDSNumber of values142313Minimum50,764,7890,285025% Percentile304,826,1117,05Median213392,5247,6475% Percentile10650228,9144,3Maximum550403043671,7Mean10320316,1122,7Std. Deviation17860647,9185,1Std. Error4773135,151,33 [Display omitted] [Display omitted] Disclosures:No relevant conflicts of interest to declare.

Skewing of the T Cell Receptor Gene Repertoire and Public Clonotypes in Cytotoxic T Cells of Patients with Chronic Idiopathic Neutropenia: A Role for Antigen Selection in Disease Development

AbstractAbstract 831Chronic idiopathic neutropenia (CIN) is a disorder of neutrophil production usually characterized by benign and asymptomatic course and female predominance. The defective hematopoiesis in CIN can be mainly attributed to accelerated Fas-mediated death of the CD34+/CD33+ granulocytic progenitor cells, secondary to an inflammatory bone marrow (BM) microenvironment. Crucial to CIN pathogenesis are the increased numbers of activated T cells identified in both peripheral blood (PB) and BM of CIN patients. Recently, using flow cytometry and CDR3 spectratyping, we obtained for the first time evidence for expanded T cell populations alluding to repertore skewing in both PB and BM of patients with CIN, but more prominent in the BM CD8+ subset. Prompted by these fndings, here we significantly extended our studies of the cytotoxic T cell responses in CIN in order to obtain a comprehensive view of the role of antigen selection in CIN pathogenesis. The study included 18 patients with CIN, 17 females and 1 male, diagnosed according to the established criterial for CIN. TRBV-TRBD-TRBJ gene rearrangements were amplified on either genomic DNA or cDNA isolated from CD8+ cells of PB (n=6) or BM (n=12) samples. PCR products were subcloned by transformation into E.Coli/TOP10F’ competent bacteria and individual colonies were chosen randomly and subjected to Sanger sequencing. Sequence data were analyzed using the International imMunoGenetics information system and more particularly the IMGT/V-QUEST tool. Overall, 507 TRBV-TRBD-TRBJ gene rearrangements were analyzed (19-30/case) of which 466 were productive since they used functional TRBV genes and also carried in-frame CDR3s. A polyclonal profile was seen in only 3/18 cases (16.7%). The remaining cases were found to carry clusters of identical rearrangements corresponding to distinct immunodominant clonotypes. The frequency of each clonotype was determined by dividing the number of identical sequences by the total number of subcloned sequences analyzed. In 10/18 cases (55.5%), the dominant clonotype accounted for 12.8–22.6% of the total, whereas in 5/18 cases (27.8%) it accounted for 34.2–68.4% of the total. The TRBV28 gene was used by the dominant clonotype of three different CIN cases; the TRBV10-2, TRBV10-3, TRB19, and TRBV7-8 genes were identified in the major clonotypes of two cases each. Importantly, cluster analysis of the CDR3 sequences of all CIN cases of the present study identified 4 different rearrangements that were shared by different patients (public clonotypes). In conclusion, the present study strongly suggests that CIN may result from an autoimmune reaction directed against granulocytic progenitors triggered by a restricted range of, as yet, unidentified antigen(s). The finding of public clonotypes may indicate that public antigenic stimuli and/or shared immune processes underlie CIN development, at least for a proportion of cases. Overall, our results further support the concept that CIN may share common pathophysiologic mechanisms with other disorders characterized by T-cell and cytokine mediated suppression of hematopoiesis, perhaps representing a milder extreme within the spectrum of these acquired immune-mediated BM failure syndromes. Disclosures:No relevant conflicts of interest to declare.