Increased frequency and specific reactivity of serum antinuclear antibodies in patients with nonimmune chronic idiopathic neutropenia of adults

Chronic Neutropenia in Childhood: Experience From a Single Center

Chronic neutropenia (CN) is defined as neutropenia that persists for >3 months; it is caused by a heterogeneous group of diseases in children. The aim of the present study was to evaluate the significance and clinical manifestations of CN in children at a single children's hospital. Between October 2004 and April 2014, CN patient data were evaluated retrospectively. Thirty-one patients were assessed in this study. Thirteen of them (41.9%) were younger than 12 months of age at initial diagnosis. There was no difference in the absolute number of neutrophils at diagnosis between the children aged younger than 12 months and those aged 12 months and older at CN onset. Twenty-two of the patients (70.9%) were diagnosed during treatment for acute infections. A total of 11 patients (35.5%) were hospitalized because of recurrent infections. Most of the recurrent infections occurred in the lungs (81.8%). Congenital neutropenia (CoN) was identified in 14 patients (45.1%). Eight of 14 patients (57.1%) required granulocyte-colony stimulating factor treatment, and none of them experienced adverse effects from this treatment. Fifteen patients (48.3%) were diagnosed with idiopathic neutropenia. Comparison between the idiopathic and CoN groups revealed no differences in age, the absolute number of neutrophils, or the presence of infection at diagnosis; however, differences were detected in sex and the rate of spontaneous recovery from neutropenia. Ten of the patients (32.2%) experienced spontaneous recovery from neutropenia during a follow-up period of 7 to 52 months. In current study, we found a higher CoN ratio in the CN patients compared with previous reports, which may be due to the high rate of consanguineous marriages in our country. However, the finding of CN requires several laboratory investigations, prolonged follow-up, and advanced molecular analysis, and its etiology can remain idiopathic.

Non-immune chronic idiopathic neutropenia of adult: an overview

There is strong evidence that non-immune chronic idiopathic neutropenia of adult is a cytokine-mediated syndrome characterized by (a) neutropenia of varying degree associated with a low number of lineage-specific CD34+ cells and increased production of inhibitors of hematopoiesis, including transforming growth factor-beta1 and tumor necrosis factor-alpha; (b) lymphopenia due to selective loss of primed/memory T-cells and NK cells; (c) increased splenic volume on ultrasonography in 48.1% of patients; (d) osteopenia and/or osteoporosis in 60.0% of patients; (e) anemia, mostly of the type of anemia of chronic disease, in 15.6% of patients; (f) features of chronic antigenic stimulation, including increased proportion of bone marrow plasma cells, increased serum levels of IgG1 and/or IgA, increased frequency of monoclonal gammopathy of undetermined significance, increased frequency of antinuclear antibodies with specific reactivity, and increased serum levels of circulating immune complexes; and (g) increased concentrations of a variety of macrophage-derived pro-inflammatory cytokines and chemokines capable of affecting bone metabolism, bone marrow function, and leukocyte trafficking. All these findings are suggestive of the existence of an unrecognized low-grade chronic inflammatory process which may be involved in the pathogenesis of the disorder. Neutropenia in these patients is probably the result of a combination of at least three factors, reduced neutrophil production in bone marrow, enhanced neutrophil extravasation, and increased sequestration and/or extravasation of neutrophils into the spleen.

Patients with non-immune chronic idiopathic neutropenia syndrome have increased splenic volume on ultrasonography

Clinically detectable splenomegaly is rarely seen in patients with non-immune chronic idiopathic neutropenia syndrome (NI-CINS). Using ultrasound, we estimated splenic volume in 52 NI-CINS patients and 14 age- and sex-matched normal controls by determining the "corrected splenic index" (CSI) from the product of length, width and thickness of the organ expressed in cm3/m2 body surface area. We found that CSI was significantly higher in the group of patients compared to controls (202.8 +/- 82.0 vs. 133.8 +/- 28.1 cm3/m2, P=0.003), and that individual CSI values was inversely correlated with the number of circulating neutrophils (r=-0.5097, P < 0.0001). About 48.1% of the patients had CSI above 190 cm3/m2 body surface, representing the upper 95% confidence limit of values found in the controls. Patients also had increased serum concentrations of pro-inflammatory cytokines and chemokines mainly produced by activated macrophages (IL-1beta, TNF-alpha, RANTES and IL-8), as well as increased serum levels of soluble cell adhesion molecules derived from activated endothelium (sE-Selectin, sICAM and sVCAM). We hypothesize that the increased splenic volume in NI-CINS patients may be due to the accumulation of activated macrophages inside the spleen, possibly as the result of an unrecognized low-grade chronic inflammatory process. The nature of such an inflammation is unknown. A study was designed to search for viral or bacterial genomic material in patients' bone marrow stromal macrophages in which the unknown causal agent might be located.