Autoimmune neutropenia

Neutropenia in Childhood-A Narrative Review and Practical Diagnostic Approach

Neutropenia refers to a decrease in the absolute neutrophil count according to age and race norms and poses a common concern in pediatric practice. Neutrophils serve as host defenders and act crucially in acute inflammation procedures. In this narrative review, we systematically present causes of neutropenia in childhood, mainly adopting the pathophysiological classification of Frater, thereby studying (1) neutropenia with reduced bone marrow reserve, (2) secondary neutropenia with reduced bone marrow reserve, and (3) neutropenia with normal bone marrow reserve. Different conditions in each category are thoroughly discussed and practically approached from the clinician's point of view. Secondary mild to moderate neutropenia is usually benign due to childhood viral infections and is expected to resolve in 2-4 weeks. Bacterial and fungal agents are also associated with transient neutropenia, although fever with severe neutropenia constitutes a medical emergency. Drug-induced and immune neutropenias should be suspected following a careful history and a detailed clinical examination. Cytotoxic chemotherapies treating malignancies are responsible for severe neutropenia and neutropenic shock. Rare genetic neutropenias usually manifest with major infections early in life. Our review of taxonomies clinical findings and associates them to specific neutropenia disorders. We consequently propose a practical diagnostic algorithm for managing neutropenic children.

Clinical significance of human neutrophil antigen-1 antibodies in children with neutropenia

Primary autoimmune neutropenia in young children is characterized by chronic neutropenia and positivity for antibodies against human neutrophil antigens (HNAs). This study analyzed the clinical characteristics of 402 children with neutropenia to identify differences between those with and without HNA-1 antibodies (HNA1abs). HNAabs in sera were detected by granulocyte immunofluorescence testing using flow cytometry. Relative fluorescence intensity (RFI) values were used to divide patients into positive (PG, n = 302), borderline (BG, n = 34), and negative (NG, n = 66) groups. The antibodies reacted to HNA-1a alone (59%), HNA-1b alone (1%), and HNA-1a/1b (40%). The PG had a significantly lower absolute neutrophil count before definitive diagnosis and a 1.6- to 2-times greater risk of hospitalization during neutropenia than the other groups. The median duration of neutropenia was longest in the PG at 25 months, followed by 20 months in the BG and 14 months in the NG. This large-scale cohort characterizes clinically distinct groups using the RFI value for HNA1abs in young children with neutropenia. Detection of HNA1abs may aid in understanding the clinical characteristics of children with neutropenia.

Evaluating safety risks of whole-body cryotherapy/cryostimulation (WBC): a scoping review from an international consortium

Over the two last decades, whole-body cryotherapy/cryostimulation (WBC) has emerged as an exciting non-pharmacological treatment influencing inflammatory events at a cellular and physiological level, which can result in improved sleep quality, faster neuromuscular recovery after high-intensity exercise, and chronic pain relief for patients suffering different types of diseases (fibromyalgia, rheumatism, arthritis). Some evidence even suggests that WBC has benefits on mental health (depression, anxiety disorders) and cognitive functions in both adults and older adults, due to increased circulating BDNF levels. Recently, some safety concerns have been expressed by influential public health authorities (e.g., FDA, INSERM) based on reports from patients who developed adverse events upon or following WBC treatment. However, part of the data used to support these claims involved individuals whose entire body (except head) was exposed to extreme cold vaporized liquid nitrogen while standing in a narrow bathtub. Such a procedure is known as partial-body cryotherapy (PBC), and is often erroneously mistaken to be whole-body cryotherapy. Although having similarities in terms of naming and pursued aims, these two approaches are fundamentally different. The present article reviews the available literature on the main safety concerns associated with the use of true whole-body cryotherapy. English- and French-language reports of empirical studies including case reports, case series, and randomized controlled trials (RCTs) were identified through searches of PubMed, Scopus, Cochrane, and Web of Science electronic databases. Five case reports and two RCTs were included for a total of 16 documented adverse events (AEs). A critical in-depth evaluation of these AEs (type, severity, context of onset, participant's medical background, follow-up) is proposed and used to illustrate that WBC-related safety risks are within acceptable limits and can be proactively prevented by adhering to existing recommendations, contraindications, and commonsense guidelines.

An adult case of refractory autoimmune neutropenia after liver transplantation

Autoimmune neutropenia (AIN) is an exceptionally rare condition that occurs after liver transplantation. Here, we report an adult case of refractory AIN 3.5 years after liver transplantation. A 59-year-old man who underwent brain-dead donor liver transplantation in August 2018 developed rapid neutropenia (0.07 × 10⁹/L) in December 2021. The patient was diagnosed with AIN based on positivity for anti-human neutrophil antigen-1a antibody. There was no response to granulocyte colony-stimulating factor (G-CSF), prednisolone, or rituximab, and intravenous immunoglobulin (IVIg) therapy induced only a temporary recovery in neutrophil count. The patient continued to have a low neutrophil count for several months. However, the response to IVIg and G-CSF improved after the post-transplant immunosuppressant was changed from tacrolimus to cyclosporine. Post-transplant AIN has many unknown aspects. Tacrolimus-induced immunomodulation and graft-associated alloimmunity may be involved in its pathogenesis. Further studies are needed to elucidate the underlying mechanisms and explore new treatment options.

Impact of biological and non-biological treatment on hematological indices in patients with ankylosing spondylitis and psoriatic arthritis

Background

Blood dyscrasias are common in patients with rheumatic diseases, as bone marrow and blood cells can be targets for autoimmune processes. This in addition to the potentially adverse effect of the disease-modifying anti-rheumatic drugs used for the treatment of inflammatory arthritis as in psoriatic arthritis (PsA) and ankylosing spondylitis (AS) on blood counts.

Aim of this study

The aim of this study is to analyze the effect of biologic therapy on complete blood cell parameters, derived ratios, and cell volume indices in Egyptian patients with ankylosing spondylitis and psoriatic arthritis.

Results

One hundred and twenty Egyptian patients had been included, 60 have ankylosing spondylitis (AS) and 60 have psoriatic arthritis (PSA). On comparing the blood indices between the biologics and non-biologics groups of PSA patients, there was a statistically highly significant reduction in red cell distribution width (RDW%) at the biologics group than non-biologics (p < 0.006), where there was a statistically highly significant increase in Hb (hemoglobin)/RDW ratio and Hb/platelets ratio at the biologics group than non-biologics (p < 0.005).

Conclusion

As a result, biologic drugs used in rheumatology practice may have some effects on hematological parameters. In our study, no major negative effects on hematological parameters were observed in patients with AS and PsA who received Secukinumab, Adalimumab-atto, or Golimumab biologic therapy. However, the changes in the hematological indices correlates with their potent anti-inflammatory action in rheumatic patients.

The role of neutrophils in antibody-driven autoimmune cytopenias

Autoimmune cytopenias are a consequence of autoantibodies that target blood cell lineages and mark them for their accelerated destruction, mostly through phagocytosis by monocytes and macrophages and complement activation. Neutrophils, although equipped with Fc and complement receptors and effector mechanisms that are critical in other autoimmune conditions, remained long overlooked. Recent reports, however, propose a new and possibly critical role of neutrophils. In this review, we gathered available evidence on the contribution of neutrophils to the development, onset, and consequences of autoantibody-dependent cytopenias.

Analysis of hematological parameters in rheumatoid arthritis patients receiving biological therapy: contribution to prevention of avoidable hematological complications

Administration of biological therapy (BT) in rheumatoid arthritis (RA) patients is often associated with hematological complications, which result in switching among therapies. Thus, there is an instant need for suitable screening parameters that will help to individualize the therapy and minimize the onset of adverse effects. We analyzed the hematological profile of 99 RA patients receiving TNFα (Adalimumab - ADA, Golimumab - GOL, Etanercept - ETA) or IL-6 receptor (Tocilizumab - TCZ) inhibitors in order to find possible indicators to improve personalization of RA therapy. BTs significantly affect the levels of observed hematological parameters. In contrast to TNF-α inhibitors, TCZ normalized almost all monitored hematological parameters to values of healthy donors. Only GOL from the TNF-α inhibitors studied, was able to normalize neutrophil counts, as well as platelet indicators. Importantly, effects on the blood parameters (e.g. lymphocytes or platelet count) differ even within the same therapeutic group (anti-TNFα). Variable effects of individual biological agents in RA treatment point to importance to evaluate the patient's hematological profile to improve the selection of suitable BT. It will help to personalize the administration of BT and prevent unnecessary switching from an effective therapy just because of provocation of avoidable hematological complications.

Neutropenia and Large Granular Lymphocyte Leukemia: From Pathogenesis to Therapeutic Options

Large granular lymphocyte leukemia (LGLL) is a rare lymphoproliferative disorder characterized by the clonal expansion of cytotoxic T-LGL or NK cells. Chronic isolated neutropenia represents the clinical hallmark of the disease, being present in up to 80% of cases. New advances were made in the biological characterization of neutropenia in these patients, in particular STAT3 mutations and a discrete immunophenotype are now recognized as relevant features. Nevertheless, the etiology of LGLL-related neutropenia is not completely elucidated and several mechanisms, including humoral abnormalities, bone marrow infiltration/substitution and cell-mediated cytotoxicity might cooperate to its pathogenesis. As a consequence of the multifactorial nature of LGLL-related neutropenia, a targeted therapeutic approach for neutropenic patients has not been developed yet; moreover, specific guidelines based on prospective trials are still lacking, thus making the treatment of this disorder a complex and challenging task. Immunosuppressive therapy represents the current, although poorly effective, therapeutic strategy. The recent identification of a STAT3-mediated miR-146b down-regulation in neutropenic T-LGLL patients emphasized the pathogenetic role of STAT3 activation in neutropenia development. Accordingly, JAK/STAT3 axis inhibition and miR-146b restoration might represent tempting strategies and should be prospectively evaluated for the treatment of neutropenic LGLL patients.

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.

Infant Pyogenic Liver Abscess Complicated With Autoimmune Neutropenia: Two Cases

Approximately 90% of patients with autoimmune neutropenia (AIN) suffer from mild infections although neutrophil count often decreases to <500/μL. Here, we report 2 cases of infant pyogenic liver abscess complicated with AIN. We should consider the possibility of AIN as an underlying disease when diagnosing pyogenic liver abscess during childhood.

Primary autoimmune neutropenia of infancy and childhood in a cohort of patients from western Romania

Neutropenia is commonly diagnosed in pediatric clinics. Due to the special vulnerability of neutropenic patients, the assessment of the etiopathogenic background of neutropenia is mandatory. In this retrospective cross-sectional cohort study, we aimed to establish the status of primary autoimmune neutropenia (AIN) from the point of view of its clinical and biological features and its outcome in a cohort of pediatric patients. We recorded all of the 3,488 cases consecutively admitted to our hospital for different diagnoses but presenting neutropenia, during a period of 3 years (January 2016 to December 2018). We had to exclude 224 patients from the analysis due to incomplete data. Our study focused on patients with AIN or chronic benign neutropenia of infancy and childhood. In these patients, a granulocyte antibody screening by granulocyte immunofluorescence test (GIFT) and the granulocyte agglutination test (GAT) were performed. Regarding their pathogenic background, 0.1% of the patients presenting neutropenia were congenital forms, the rest being acquired forms. Primary AIN was encountered in 18 cases, representing approximately 0.5%. The median age at onset for primary AIN was 7.5 months. Male/female ratio in AIN was 1.94. In 72% of the patients with AIN, neutropenia was severe during the course of disease. In 3 patients, both GIFT and GAT were positive and in 8 patients, only GIFT was positive. For the remaining 7 patients (39%), both GIFT and GAT revealed negative results. 50% of the patients needed hospitalization, but only 3 patients presented severe infections. On-demand G-CSF was administered in 22% of the patients. Our study provides insight with regard to neutropenia, showing the high frequency and etiological diversity in childhood. Primary AIN is usually diagnosed by exclusion of the other causes of neutropenia. GIFT and GAT are useful, but rarely available diagnostic tools for the confirmation of primary AIN.

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.

A Rare Case of Adult Autoimmune Neutropenia Successfully Treated with Prednisolone

Autoimmune neutropenia (AIN) is a rare disorder that may cause life-threatening infections. In adults, most cases are secondary to other pathological conditions, and primary AIN is extremely rare. We herein report a case involving a 57-year-old woman diagnosed with AIN. A granulocyte immunofluorescence test detected autoantibodies against human neutrophil antigens in her serum, while various examinations revealed no other causes of neutropenia, suggesting her AIN was primary. She was refractory to granulocyte-colony-stimulating factor but responded to prednisolone. Her neutrophil count remained normal after gradual discontinuation of prednisolone. Diagnostic procedures and optimal treatments for this disorder need to be established.

Atypical aleukemic presentation of large granular lymphocytic leukemia: a case report

Large granular lymphocytic leukemia (LGLL) is a rare lymphoproliferative disorder of transformed natural killer or T-cells attributed to chronic exposure to the proinflammatory cytokine IL-15. Diagnosis of the majority of T-cell LGLL is established by documenting clonal large granular lymphocytes (LGLs) in peripheral blood, by morphology and immunophenotype. The proteasome inhibitor bortezomib is known to target molecular pathways downstream of the IL-15 receptor signaling and has been proposed as a therapy in these patients. We report an uncommon presentation of LGLL with chronic neutropenia lacking typical blood LGLs, which failed to respond to bortezomib but obtained a very good partial remission with a classical methotrexate regimen.

Severe chronic primary neutropenia in adults: report on a series of 108 patients

Severe CPN in adults is a benign entity without secondary myeloid malignancies. Neutrophil count at diagnosis is the only predictive factor of severe infections.

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.