Diagnostic criteria for autoimmune neutropenia

Diagnosis of autoimmune neutropenia in a 10-month-old boy - a case report

Neutropenia, congenital or acquired, is related to impaired granulocyte production in the bone marrow or increased destruction by antibodies. Autoimmune neutropenia of infancy (AIN) is associated with the occurrence of antineutrophil antibodies. AIN is the most common cause of neutropenia in infants and young children. However, its incidence is low. Detection of anti-neutrophil antibodies is an important step in confirming the diagnosis of AIN, although their detection is difficult due to low titer and poor avidity. In differential diagnosis, another cause of neutropenia should be considered, such as a drug-induced mechanism, viral infection, autoimmune and metabolic disease, hematological conditions or immune deficiency syndromes. Despite the benign course of AIN, serious infectious complications can occur. Spontaneous remission of neutropenia was observed in 95% of patients during 24 months of follow-up. We present a case of a 10-month-old boy with deafness, heart defect and Morgagni-Larrey hernia diagnosed in our department because of formation of a skin abscess due to autoimmune neutropenia.

Evans' Syndrome: From Diagnosis to Treatment

Evans' syndrome (ES) is defined as the concomitant or sequential association of warm auto-immune haemolytic anaemia (AIHA) with immune thrombocytopenia (ITP), and less frequently autoimmune neutropenia. ES is a rare situation that represents up to 7% of AIHA and around 2% of ITP. When AIHA and ITP occurred concomitantly, the diagnosis procedure must rule out differential diagnoses such as thrombotic microangiopathies, anaemia due to bleedings complicating ITP, vitamin deficiencies, myelodysplastic syndromes, paroxysmal nocturnal haemoglobinuria, or specific conditions like HELLP when occurring during pregnancy. As for isolated auto-immune cytopenia (AIC), the determination of the primary or secondary nature of ES is important. Indeed, the association of ES with other diseases such as haematological malignancies, systemic lupus erythematosus, infections, or primary immune deficiencies can interfere with its management or alter its prognosis. Due to the rarity of the disease, the treatment of ES is mostly extrapolated from what is recommended for isolated AIC and mostly relies on corticosteroids, rituximab, splenectomy, and supportive therapies. The place for thrombopoietin receptor agonists, erythropoietin, immunosuppressants, haematopoietic cell transplantation, and thromboprophylaxis is also discussed in this review. Despite continuous progress in the management of AIC and a gradual increase in ES survival, the mortality due to ES remains higher than the ones of isolated AIC, supporting the need for an improvement in ES management.

Autoimmune cytopenias (AIC) following allogeneic haematopoietic stem cell transplant for acquired aplastic anaemia: a joint study of the Autoimmune Diseases and Severe Aplastic Anaemia Working Parties (ADWP/SAAWP) of the European Society for Blood and Marrow Transplantation (EBMT)

This retrospective study explored the incidence of autoimmune cytopenia (AIC) in 530 paediatric and adult patients with acquired aplastic anaemia (aAA) who underwent first allogeneic HSCT between 2002 and 2012. AIC was a rare complication with a cumulative incidence of AIC at 1, 3, 5 and 10 years post HSCT of 2.5% (1.2-3.9 95% CI), 4.4% (2.6-6.2 95% CI), 4.6% (2.8-6.5 95% CI) and 5.1% (3.1-7.2 95% CI). Overall survival at 5 years after diagnosis of AIC was 85.9% (71-100 95% CI). Twenty-five patients were diagnosed with AIC at a median of 10.6 (2.6-91.5) months post HSCT. Eight (32%) patients were diagnosed with immune thrombocytopenia (ITP), seven (28%) with autoimmune haemolytic anaemia (AIHA), seven (24%) with Evans syndrome and four (16%) with autoimmune neutropenia (AIN). Treatment strategies were heterogeneous. Complete responses were seen in 12 of 25 patients, with death in three patients. In multivariable Cox analysis of a subgroup of 475 patients, peripheral blood stem cell (PBSC) transplant was associated with higher risk of AIC compared with bone marrow (BM) when conditioning regimens contained fludarabine and/or alemtuzumab (2.81 [1.06-7.49 95% CI]; p = 0.038), or anti-thymocyte globulin (ATG) (2.86 [1.11-7.37 95% CI]; p = 0.029). Myeloablative conditioning was associated with a lower risk of AIC compared with reduced intensity conditioning (RIC) in fludarabine and/or alemtuzumab (0.34 [0.12-0.98 95% CI]; p = 0.046) and ATG containing regimens (0.34 [0.12-0.95 95% CI]; p = 0.04). These findings provide clinically useful information regarding the incidence of a rare and potentially life-threatening complication of allogeneic HSCT for aAA, and further support for BM as the preferred stem cell source for transplant of patients with aAA.

High-Throughput Immunogenetics Reveals a Lack of Physiological T Cell Clusters in Patients With Autoimmune Cytopenias

Autoimmune cytopenias (AIC) such as immune thrombocytopenia or autoimmune hemolytic anemia are claimed to be essentially driven by a dysregulated immune system. Using next-generation immunosequencing we profiled 59 T and B cell repertoires (TRB and IGH) of 25 newly diagnosed patients with primary or secondary (lymphoma-associated) AIC to test the hypothesis if these patients present a disease-specific immunological signature that could reveal pathophysiological clues and eventually be exploited as blood-based biomarker. Global TRB and IGH repertoire metrics as well as VJ gene usage distribution showed uniform characteristics for all lymphoma patients (high clonality and preferential usage of specific TRBV- and TRBJ genes), but no AIC-specific signature. Since T cell immune reactions toward antigens are unique and polyclonal, we clustered TCRβ clones in-silico based on target recognition using the GLIPH (grouping of lymphocyte interactions by paratope hotspots) algorithm. This analysis revealed a considerable lack of physiological T cell clusters in patients with primary AIC. Interestingly, this signature did not discriminate between the different subentities of AIC and was also found in an independent cohort of 23 patients with active autoimmune hepatitis. Taken together, our data suggests that the identified T cell cluster signature could represent a blood biomarker of autoimmune conditions in general and should be functionally validated in future studies.

Evans Syndrome in Childhood: Long Term Follow-Up and the Evolution in Primary Immunodeficiency or Rheumatological Disease

Evans syndrome (ES) is a rare but challenging condition, characterized by recurrent and refractory cytopenia episodes. Recent discoveries highlighted that an appropriate diagnostic workup is fundamental to identify an underlying immune dysregulation such as primary immunodeficiencies or a rheumatological disease. We hereby describe clinical features and laboratory results of 12 pediatric patients affected by ES referred to the Pediatric Onco-Hematology Unit of Bologna. Patients experienced a median of four acute episodes of cytopenia with 9 years as median age at the onset of symptoms. In 8/12 (67%) patients an underlying etiology, primary immunodeficiencies, or rheumatological disease was identified. In 4/12 children, other immune manifestations were associated (Thyroiditis, Celiac disease, Psoriasis, Vitiligo, Myositis, Membranoproliferative Glomerulonephritis). ES remained the primary diagnosis in four patients (33%). At a median follow-up time of 4 years, 5/12 (42%) patients revealed a chronic ITP, partially responsive to second line therapy. Immunoglobulin Replacement Therapy (IRT) was effective with a good hematological values control in three patients with a secondary ES (ALPS, CVID, and a patient with Rubinstein Taybi Syndrome and a progressive severe B cell deficiency with hypogammaglobulinemia). Our experience highlights that, in pediatric patients, ES is often only the first manifestation of an immunological or rheumatological disease, especially when cytopenias are persistent or resistant to therapy, with an early-onset or when are associated with lymphadenopathy.

Neutropenia in 6 cases of childhood onset type 1 diabetes and its possible mechanisms

OBJECTIVE

Type 1 diabetes (T1D) is a chronic inflammatory disease caused by a selective destruction of the pancreatic β-cells. There are few reports on peripheral neutropenia in T1D for different reasons. We reported 6 cases of childhood onset T1D combined with neutropenia and explored its possible mechanisms.

METHODS

The clinical diagnosis and treatment course of 6 cases of childhood onset T1D combined with neutropenia, who were hospitalized in our hospital from January 2013 to December 2016, were studied retrospectively.

RESULTS

We have diagnosed and treated 38 cases of childhood onset T1D during this period, while only 6 cases (15.79%) had neutropenia. The diagnostic ages of the 6 cases ranged from 5 to 12 years. Diabetic ketoacidosis (DKA) was complicated in 5 cases. Neutropenia happened within 14 to 21 days of the onset of disease and 3 to 11 days after using insulin, respectively, and returned spontaneously to normal range within 5 to 9 days. The serum levels of granulocyte colony-stimulating factor (G-CSF) and granulocyte macrophage colony-stimulating factor (GM-CSF) increased slightly before the usage of insulin in all 6 cases, and decreased to normal range after the usage of insulin.

CONCLUSION

Neutropenia can be seen in childhood onset T1D, and can return spontaneously to normal range without special treatments. The possible mechanisms might be the regulation effects of insulin on G-CSF and GM-CSF.

Common Variable Immunodeficiency Non-Infectious Disease Endotypes Redefined Using Unbiased Network Clustering in Large Electronic Datasets

Common variable immunodeficiency (CVID) is increasingly recognized for its association with autoimmune and inflammatory complications. Despite recent advances in immunophenotypic and genetic discovery, clinical care of CVID remains limited by our inability to accurately model risk for non-infectious disease development. Herein, we demonstrate the utility of unbiased network clustering as a novel method to analyze inter-relationships between non-infectious disease outcomes in CVID using databases at the United States Immunodeficiency Network (USIDNET), the centralized immunodeficiency registry of the United States, and Partners, a tertiary care network in Boston, MA, USA, with a shared electronic medical record amenable to natural language processing. Immunophenotypes were comparable in terms of native antibody deficiencies, low titer response to pneumococcus, and B cell maturation arrest. However, recorded non-infectious disease outcomes were more substantial in the Partners cohort across the spectrum of lymphoproliferation, cytopenias, autoimmunity, atopy, and malignancy. Using unbiased network clustering to analyze 34 non-infectious disease outcomes in the Partners cohort, we further identified unique patterns of lymphoproliferative (two clusters), autoimmune (two clusters), and atopic (one cluster) disease that were defined as CVID non-infectious endotypes according to discrete and non-overlapping immunophenotypes. Markers were both previously described {high serum IgE in the atopic cluster [odds ratio (OR) 6.5] and low class-switched memory B cells in the total lymphoproliferative cluster (OR 9.2)} and novel [low serum C3 in the total lymphoproliferative cluster (OR 5.1)]. Mortality risk in the Partners cohort was significantly associated with individual non-infectious disease outcomes as well as lymphoproliferative cluster 2, specifically (OR 5.9). In contrast, unbiased network clustering failed to associate known comorbidities in the adult USIDNET cohort. Together, these data suggest that unbiased network clustering can be used in CVID to redefine non-infectious disease inter-relationships; however, applicability may be limited to datasets well annotated through mechanisms such as natural language processing. The lymphoproliferative, autoimmune, and atopic Partners CVID endotypes herein described can be used moving forward to streamline genetic and biomarker discovery and to facilitate early screening and intervention in CVID patients at highest risk for autoimmune and inflammatory progression.

Abatacept and granulocyte-colony stimulating factor in a patient with rheumatoid arthritis and neutropenia

Neutropenia in patients with inflammatory diseases increases the risk of infection due to the disease itself and the related immunosuppressive treatments. We report the case of a 54-year-old female with rheumatoid arthritis and following development of chronic neutropenia. All investigations excluded pathogenic relations with drugs and/or other clinical situations; the gravity of neutropenia required a treatment with G-CSF and the increased articular inflammatory activity justified a biologic-therapy, abatacept (CTLA4 inhibitors). The juxtaposition of immunostimulants and immunosuppressors led to great effectiveness for both hematological and rheumatic issues. To date, while some biologic drugs (TNF, IL6R and CD20 inhibitors) have reported relations with neutropenia, no such relevance subsists for Abatacept. Our case reports the experience of the safe effective use of abatacept and G-CSF for 8 years.

An Elderly Woman with Anti-neutrophil Antibody-positive Agranulocytosis Who Responded to High-dose Intravenous Methylprednisolone

Although anti-neutrophil antibodies (ANAs) often exist and immunoreaction may be involved in agranulocytosis, few reports have so far described ANA-positive cases of agranulocytosis with an unknown etiology. We herein describe the case of a 69-year-old woman who presented with ANA-positive agranulocytosis. In this case, both the withdrawal of the drugs that had possibly caused neutropenia and the use of granulocyte-colony stimulating factor (G-CSF) were ineffective treatment measures. Approximately 2 weeks after the discontinuation of the suspected drugs, we initiated corticosteroid pulse therapy; the neutrophil count recovered by day 19 of steroid therapy. High-dose methylprednisolone therapy should thus be considered for patients demonstrating ANA-positive agranulocytosis with an unknown etiology that is refractory to G-CSF treatment.

[Advances in research on childhood neutropenia]

Neutrophils, an important type of human immune cells, are involved in host defense against infections. Neutropenia refers to a group of diseases manifesting as a reduction in the absolute value of mature neutrophils and is often accompanied by an increased risk of bacterial infection. According to etiology and pathogenesis, neutropenia is classified into congenital and acquired neutropenia. This article reviews the current research status and advances in the etiology of neutropenia in children. A deep understanding of the etiology of neutropenia helps to improve the diagnosis and treatment of this disease.

Immune neutropenias of infancy and childhood

BACKGROUND

Anti-neutrophil antibodies are a well-recognized cause of neutropenia, producing a potential increase in risk of infection: in the majority of patients antibodies react against antigens located on the IgG Fc receptor type 3b (FcRIIIb), but other target antigens have been identified.

DATA SOURCES

In this review the most important papers of auto and alloimmune neutropenias of infancy and childhood were analyzed. PubMed, Google Scholar and Thompson ISI Web of Knowledge were searched for identifying relevant papers.

RESULTS

Primary autoimmune neutropenia of infancy is mostly a benign condition with self-limited course, whereas isolated alloimmune neonatal neutropenia or secondary autoimmune neutropenia may be occasionally complicated by severe infections.

CONCLUSION

Granulocyte colony stimulating factor is an effective therapy for patients affected by all types of autoimmune and alloimmune neutropenia, even though most of them do not need any therapy.

How we diagnose and treat neutropenia in adults

Neutropenias (NPs), being acute and often transient, or chronic, range from life-threatening conditions with very low absolute neutrophil blood counts (ANC) to disorders characterized by only mild NP and of no obvious significance for health. Many are caused by genetic variations/mutations, e.g. the benign familial NP and the chronic severe NPs (e.g. Kostmann disease). Some of the latter are associated with various bodily malformations. Many of the mild-to-moderate NPs are signs of underlying disorders that need specialized treatments (e.g. HIV, hepatitis, autoimmune disorders, the large granular lymphocyte syndrome). We provide here means for the evaluation of a previously unknown NP, suggest a triage and treatments.

Management of neutropenia in patients with rheumatoid arthritis

Neutropenia is defined as a neutrophil count lower than 1.5g/L, with categorization as mild, moderate, or severe when the count is 1.5-1g/L, 1-0.5g/L, or<0.5g/L, respectively. The main complication is infection, whose risk increases with the depth and duration of the neutropenia. Comprehensive etiological investigations are mandatory to determine the best treatment strategy. Constitutional neutropenia is rarely seen in everyday rheumatology practice. It predominantly affects patients of African descent and is usually moderate and well tolerated. Congenital neutropenia due to genetic abnormalities is severe and chiefly seen in the pediatric population. Most cases of neutropenia in patients with rheumatoid arthritis (RA) are acquired. Medications are the most common causes, making detailed history-taking crucial. Many medications used to treat RA can induce neutropenia. Folic acid deficiency should be sought routinely in patients taking methotrexate. A less common cause of neutropenia is an RA-related autoimmune reaction. Splenomegaly suggests Felty's syndrome, which is accompanied with large granular lymphocytic (LGL) leukemia in 40% of cases. The treatment depends on the depth of the neutropenia and findings from the etiological workup. A neutrophil count below 0.5g/L, a fever, and the presence of clinical signs indicate a life-threatening condition requiring emergent treatment. In other patients, the first step is immediate discontinuation of any possibly involved drugs, simultaneously with the etiological workup.

Missing Cells: Pathophysiology, Diagnosis, and Management of (Pan)Cytopenia in Childhood

Peripheral blood cytopenia in children can be due to a variety of acquired or inherited diseases. Genetic disorders affecting a single hematopoietic lineage are frequently characterized by typical bone marrow findings, such as lack of progenitors or maturation arrest in congenital neutropenia or a lack of megakaryocytes in congenital amegakaryocytic thrombocytopenia, whereas antibody-mediated diseases such as autoimmune neutropenia are associated with a rather unremarkable bone marrow morphology. By contrast, pancytopenia is frequently associated with a hypocellular bone marrow, and the differential diagnosis includes acquired aplastic anemia, myelodysplastic syndrome, inherited bone marrow failure syndromes such as Fanconi anemia and dyskeratosis congenita, and a variety of immunological disorders including hemophagocytic lymphohistiocytosis. Thorough bone marrow analysis is of special importance for the diagnostic work-up of most patients. Cellularity, cellular composition, and dysplastic signs are the cornerstones of the differential diagnosis. Pancytopenia in the presence of a normo- or hypercellular marrow with dysplastic changes may indicate myelodysplastic syndrome. More challenging for the hematologist is the evaluation of the hypocellular bone marrow. Although aplastic anemia and hypocellular refractory cytopenia of childhood (RCC) can reliably be differentiated on a morphological level, the overlapping pathophysiology remains a significant challenge for the choice of the therapeutic strategy. Furthermore, inherited bone marrow failure syndromes are usually associated with the morphological picture of RCC, and the recognition of these entities is essential as they often present a multisystem disease requiring different diagnostic and therapeutic approaches. This paper gives an overview over the different disease entities presenting with (pan)cytopenia, their pathophysiology, characteristic bone marrow findings, and therapeutic approaches.