Cyclic and chronic neutropenia

The multidisciplinary approach to diagnosing inborn errors of immunity: a comprehensive review of discipline-based manifestations

INTRODUCTION

Congenital immunodeficiency is named primary immunodeficiency (PID), and more recently inborn errors of immunity (IEI). There are more than 485 conditions classified as IEI, with a wide spectrum of clinical and laboratory manifestations.

AREAS COVERED

Regardless of the developing knowledge of IEI, many physicians do not think of IEI when approaching the patient's complaint, which leads to delayed diagnosis, misdiagnosis, serious infectious and noninfectious complications, permanent end-organ damage, and even death. Due to the various manifestations of IEI and the wide spectrum of associated conditions, patients refer to specialists in different disciplines of medicine and undergo - mainly symptomatic - treatments, and because IEI are not included in physicians' differential diagnosis, the main disease remains undiagnosed.

EXPERT OPINION

A multidisciplinary approach may be a proper solution. Manifestations and the importance of a multidisciplinary approach in the diagnosis of main groups of IEI are discussed in this article.

Diagnosis and initial management of children presenting with premature loss of primary teeth associated with a systemic condition: A scoping review and development of clinical aid

BACKGROUND

Premature loss of primary teeth (PLPT) can be a rare presentation of systemic medical conditions. Premature loss of primary teeth may present a diagnostic dilemma to paediatric dentists.

AIMS

To identify systemic conditions associated with PLPT and develop a clinical aid.

DESIGN

OVID Medline, Embase and Web of Science were searched up to March 2023. Citation searching of review publications occurred. Exclusion occurred for conference abstracts, absence of PLPT and absence of English-language full text.

RESULTS

Seven hundred and ninety-one publications were identified via databases and 476 by citation searching of review articles. Removal of 390 duplicates occurred. Following the exclusion of 466 records on abstract review, 411 publications were sought for retrieval, of which 142 met inclusion criteria. Thirty-one systemic conditions were identified. For 19 conditions, only one publication was identified. The majority of publications, 91% (n = 129), were case reports or series. Most publications, 44% (n = 62), were related to hypophosphatasia, and 25% (n = 35) were related to Papillon-Lefèvre. Diagnostic features were synthesised, and a clinical aid was produced by an iterative consensus approach.

CONCLUSIONS

A diverse range of systemic diseases are associated with PLPT. Evidence quality, however, is low, with most diseases having a low number of supporting cases. This clinical aid supports paediatric dentists in differential diagnosis and onward referral.

Cyclic Neutropenia Mimicking Crohn's Disease: Two Case Reports and a Narrative Review

Cyclic neutropenia is a rare hematological condition characterized by periodic fluctuations in neutrophil counts, with a 21-day periodicity. Clinical presentation varies from mild to severe forms of the disease, with the onset of recurrent fever, painful oral ulcers, recurrent bacterial infections, peritonitis, and septic shock. The availability of granulocyte colony-stimulating factor (G-CSF) has revolutionized the management and natural history of this disease, regulating the proliferation, differentiation, and maturation of the progenitor cells, and reducing the duration of neutropenia. Inflammatory bowel disease (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), is a group of chronic pathologies that affect the gastrointestinal tract. The onset of both diseases may be at a young age (even during childhood or adolescence), and clinical manifestations may lead to misdiagnosis, due to similar characteristics such as recurrent infections, oral ulcers, perianal abscesses, and infertility. Moreover, the two pathologies are rarely associated, with different management and therapeutic options. Here, we describe two case reports of patients who underwent surgery because of diagnosis of complicated CD. After surgery, due to persistent neutropenia, the hematologist consultant confirmed suspicions of cyclic neutropenia, and G-CSF therapy was started with benefits, underlining the crucial importance of proper differential diagnosis.

Case Report: Characterization of known (c.607G>C) and novel (c.416C>G) ELANE mutations in two Mexican families with congenital neutropenia

The most common causes of congenital neutropenia are mutations in the ELANE (Elastase, Neutrophil Expressed) gene (19p13.3), mostly in exon 5 and the distal portion of exon 4, which result in different clinical phenotypes of neutropenia. Here, we report two pathogenic mutations in ELANE, namely, c.607G>C (p.Gly203Arg) and a novel variant c.416C>G (p.Pro139Arg), found in two Mexican families ascertained via patients with congenital neutropenia who responded positively to the granulocyte colony-stimulating factor (G-CSF) treatment. These findings highlight the usefulness of identifying variants in patients with inborn errors of immunity for early clinical management and the need to rule out mosaicism in noncarrier parents with more than one case in the family.

Entecavir-induced neutropenia in an adult living donor liver transplant recipient: Successful conversion to tenofovir alafenamide

At 22 weeks post-transplantation for HBV-related cirrhosis, an adult woman developed neutropenia which was aggravated by COVID-19 (ANC 0.4 × 109/L). Covid resolution and all "conventional" modifications were ineffective. Success within 2 weeks was achieved by switching entecavir to tenofovir alafenamide. A step-by-step judicious approach to post-transplant neutropenia is vital.

Cyclic neutropenia and concomitant IgA nephropathy: a case report

BACKGROUND

IgA nephropathy (IgAN) is universally recognized as one of the most common primary glomerular diseases in all ages. Cyclic neutropenia (CN) is a rare haematologic disorder that is associated with mutations of the ELANE gene. The co-occurrence of IgAN and CN is extremely rare. This is the first case report of a patient with IgAN and genetically confirmed CN.

CASE PRESENTATION

We report a case of a 10-year-old boy who presented with recurrent viral upper respiratory tract infections accompanied by several episodes of febrile neutropenia, haematuria, proteinuria and acute kidney injury. Upon first admission, his physical examination was unremarkable. His kidney function was impaired, whereas his urine microscopy showed evidence of macroscopic haematuria and proteinuria. Further workup showed elevated IgA. The renal histology was consistent with mesangial and endocapillary hypercellularity with mild crescentic lesions, while immunofluorescence microscopy showed IgA-positive staining, which was characteristic of IgAN. Moreover, genetic testing confirmed the clinical diagnosis of CN, therefore Granulocyte colony-stimulating factor (G-CSF) was initiated to stabilize the neutrophil count. Regarding proteinuria control, the patient was initially treated with an Angiotensin-converting-enzyme inhibitor for approximately 28 months. However, due to progressive proteinuria (> 1 g/24 h), Corticosteroids (CS) were added for a period of 6 months according to the revised 2021 KDIGO guidelines with favorable outcome.

CONCLUSIONS

Patients with CN are more susceptible to recurrent viral infections, which can trigger IgAN attacks. In our case CS induced remarkable proteinuria remission. The use of G-CSF contributed to the resolution of severe neutropenic episodes, viral infections and concomitant AKI episodes, contributing to better prognosis of IgAN. Further studies are mandatory to determine whether there is a genetical predisposition for IgAN in children with CN.

Periodic Fever in Children: Etiology and Diagnostic Challenges

Periodic fever in children is an autoinflammatory illness with an unknown cause. Symptoms include frequent episodes of fever that are followed by an increase in inflammatory markers. A genetic background for periodic fever of unknown origin has been hypothesized, based on its family clustering and parallels to other autoinflammatory illnesses such as familial Mediterranean fever. Genome analysis has been used in studies to look for related gene variations in periodic fever of unknown origin in the pediatric population. 

Children with periodic fevers might be a diagnostic challenge. After ruling out the most prevalent causes, a wide variety of other possibilities are investigated. Infectious and noninfectious causes of periodic fever in children are discussed in this article.

Inflammasomes (intracellular proteins that activate interleukin (IL)-1b and IL-18) and genetic/hereditary variations are thought to be implicated in the pathogenesis of periodic fever. Evaluation and ruling out possible infective or noninfective causes is vital in the diagnosis of periodic fever in children. Investigations demonstrate that there isn't a single gene linked to it, suggesting that it may have a multifactorial or polygenic origin, with an environmental trigger causing inflammasome activation and fever flares. Treatment is usually symptomatic, with drugs such as colchicine and cimetidine having shown promising results in trials.

We explored the literature on periodic fever in children for its epidemiology, pathophysiology, the role of various genes and how they influence the disease and associated complications, and its various treatment modalities.

A patient with severe congenital neutropenia harbors a missense ELANE mutation due to paternal germline mosaicism

BACKGROUND

Clinical and genetic characteristics of ELANE mutation of a 3-year-old male who had a severe congenital neutropenia (SCN) were examined. We then investigated whether CRISPR/Cas9-mediated gene editing could correct the mutation.

PROCEDURE

The proband underwent extensive clinical assessments, such as exome sequencing and bioinformatics analysis, so that pathogenic genes could be identified. Sanger sequencing was also utilized for confirmation. The cell line, 293-ELANE, harboring ELANE mutation was generated, and the mutation was then corrected by CRISPR/Cas9-mediated homology-directed repair (HDR).

RESULTS

The ELANE gene test in the proband unveiled a heterozygous de novo missense mutation: c. 248T > A (p.V83D), which was not detected in his asymptomatic parents who had provided peripheral blood samples. We found that 46.01% of his father's sperm cells had the same mutation. These results demonstrate that the proband inherited the ELANE mutation from his father, who had an average neutrophil count but had a germline mosaicism. The highest repair efficiency of CRISPR/Cas9-mediated HDR for 293-ELANE is 4.43%.

CONCLUSIONS

We identified a missense mutation (p.V83D) in ELANE that causes SCN. This is the first report on paternal semen mosaicism of an ELANE mutation. Our study paves the way for preimplantation genetic diagnosis (PGD) based on ELANE mutation prevention and clinical treatment of congenital disabilities.

Periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome: A review

Periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome is the most common periodic fever condition in children, with most cases appearing by the age of 5. Although PFAPA is generally a self-limited condition, it can have a major impact on a child's quality of life, as well as that of their family. Recent research has continued to shed light on the genetic and immunologic factors that play a role in the pathogenesis of PFAPA. There also exists significant heterogeneity in treatment strategies, and progress has been made to develop evidence-based management strategies and establish a standard of care. This review will outline current knowledge regarding the pathogenesis of PFAPA, as well as treatment strategies and our clinical experience.

Inborn Errors of Immunity: how to diagnose them?

OBJECTIVES

Inborn Errors of Immunity are characterized by infectious conditions and manifestations of immune dysregulation. The diversity of clinical phenotypes can make it difficult to direct the laboratory investigation. This article aims to update the investigation of immunological competence in the context of primary defects of the immune system.

SOURCE OF DATA

Searches were carried out on Pubmed to review articles published in the last five years, in English, French or Spanish, using the terms "diagnosis" OR "investigation" AND "immunodeficiency" or "primary immunodeficiency" or "inborn errors of immunity" NOT "HIV". Recent textbook editions have also been consulted.

SUMMARY OF FINDINGS

The immune system competence investigation should be started based on clinical phenotypes. Relevant data are: characterization of infectious conditions (location, recurrence, types of infectious agents, response to treatment), age during symptom onset and associated manifestations (growth impairment, allergy, autoimmunity, malignancies, fever and signs of inflammation without the identification of infection or autoimmunity) and family history. These data contribute to the selection of tests to be performed.

CONCLUSIONS

The diagnostic investigation of Inborn Errors of Immunity should be guided by the clinical characterization of patients, aiming to optimize the use of complementary tests. Many diagnoses are attained only through genetic tests, which are not always available. However, the absence of a diagnosis of certainty should never delay the implementation of therapeutic measures that preserve patient life and health.

How I investigate neutropenia

Neutropenia is a common laboratory finding in adults and children. Its underlying causes are extremely heterogeneous and include benign conditions, autoimmune disorders, infections, and malignancies. The clinical laboratory plays a central role in the diagnosis of these disorders, including data derived from hematology, microbiology, molecular biology/cytogenetics, and clinical chemistry. The purpose of this review is to (a) highlight the clinical, hematologic, and molecular genetic features of the major entities resulting in neutropenia and (b) outline an algorithm-based approach to permit the classification of neutropenias.

Primary Immunodeficiencies With Defects in Innate Immunity: Focus on Orofacial Manifestations

The field of primary immunodeficiencies (PIDs) is rapidly evolving. Indeed, the number of described diseases is constantly increasing thanks to the rapid identification of novel genetic defects by next-generation sequencing. PIDs are now rather referred to as “inborn errors of immunity” due to the association between a wide range of immune dysregulation-related clinical features and the “prototypic” increased infection susceptibility. The phenotypic spectrum of PIDs is therefore very large and includes several orofacial features. However, the latter are often overshadowed by severe systemic manifestations and remain underdiagnosed. Patients with impaired innate immunity are predisposed to a variety of oral manifestations including oral infections (e.g., candidiasis, herpes gingivostomatitis), aphthous ulcers, and severe periodontal diseases. Although less frequently, they can also show orofacial developmental abnormalities. Oral lesions can even represent the main clinical manifestation of some PIDs or be inaugural, being therefore one of the first features indicating the existence of an underlying immune defect. The aim of this review is to describe the orofacial features associated with the different PIDs of innate immunity based on the new 2019 classification from the International Union of Immunological Societies (IUIS) expert committee. This review highlights the important role played by the dentist, in close collaboration with the multidisciplinary medical team, in the management and the diagnostic of these conditions.

New insights into the pathomechanism of cyclic neutropenia

Cyclic neutropenia (CyN) is a hematologic disorder in which peripheral blood absolute neutrophil counts (ANCs) show cycles of approximately 21-day intervals. The majority of CyN patients harbor ELANE mutations, but the mechanism of ANC cycling is unclear. We performed analysis of bone marrow (BM) subpopulations in CyN patients at the peak and the nadir of the ANC cycle and detected high proportions of BM hematopoietic stem cells (HSCs) and hematopoietic stem and progenitor cells (HSPCs) at the nadir of the ANC cycle, as compared with the peak. BM HSPCs produced fewer granulocyte colony-forming unit colonies at the ANC peak. To investigate the mechanism of cycling, we found that mRNA expression levels of ELANE and unfolded protein response (UPR)-related genes (ATF6, BiP (HSPA5), CHOP (DDIT3), and PERK (EIF2AK3)) were elevated, but antiapoptotic genes (Bcl-2 (BCL2) and bcl-xL (BCL2L1)) were reduced in CD34⁺ cells tested at the ANC nadir. Moreover, HSPCs revealed increased levels of reactive oxygen species and gH2AX at the ANC nadir. We suggest that in CyN patients, some HSPCs escape the UPR-induced endoplasmic reticulum (ER) stress and proliferate in response to granulocyte colony-stimulating factor (G-CSF) to a certain threshold at which UPR again affects the majority of HSPCs. There is a cyclic balance between ER stress-induced apoptosis of HSPCs and compensatory G-CSF-stimulated HSPC proliferation followed by granulocytic differentiation.

Novel ELANE Gene Mutation in a Newborn with Severe Congenital Neutropenia: Case Report and Literature Review

Severe neutropenia is defined as an absolute neutrophil count (ANC) of less than 0.5 × 10 ⁹ /L. Severe congenital neutropenia (SCN) is an inborn disorder with maturation arrest of granulocytes due to various genetic abnormalities, which may lead to immunodeficiency. Among several associated genetic mutations, the variants or heterozygous mutations of the ELANE gene coding neutrophil elastase comprise approximately 50% of the genetic causes of SCN. We present a newborn (male) with severe neutropenia due to a novel ELANE gene mutation. The newborn was born at 38 ^6/7 weeks gestation to a 25-year-old mother with hypertension and morbid obesity. Pregnancy and delivery were uncomplicated but the baby obtained a complete blood count (CBC) on day of life 2 for a work up of hyperbilirubinemia. He was noted to initially have an ANC of 0.2 × 10 ⁹ /L and 0 on subsequent blood counts. A bone marrow biopsy showed a left shift and consistent with myeloid maturation arrest. In direct DNA sequencing analysis, we found an ELANE gene mutation (Val119Glu, V119E), which may be a new gene mutation to cause SCN. The diagnosis of SCN in newborns is usually based on neutropenia identified on a routine CBC. Sufficient awareness and high suspicion of this rare disease can prevent missed or delayed diagnosis of SCN. Our analysis also suggests a new pathological mutation in the ELANE gene and supports the important role of molecular testing in SCN.

Management of tooth extraction in a patient with ELANE gene mutation-induced cyclic neutropenia: A case report

INTRODUCTION

Cyclic neutropenia (CyN) is a rare hematological disease, and patients with CyN often experience an early onset of severe periodontitis and are forced to undergo tooth extraction. Here, we report a case of a patient with CyN who showed different periodicity and oscillations of neutrophil count compared with her mother, despite sharing the same novel genetic mutation.

PATIENT CONCERNS

A 17-year-old Japanese girl who had been diagnosed with CyN shortly after birth presented to our hospital with a complaint of mobility of her teeth and gingivitis. Upon presentation, an intraoral examination was performed and revealed redness and swelling of the marginal and attached gingiva. Radiographs revealed extreme resorption of the alveolar bone and apical lesions in her mandibular lateral incisors. The patient's hematologic data demonstrated a lack of blood neutrophils (0/μL). The patient had no history of dental extraction, and her mother also had a history of CyN.

DIAGNOSES

The patient was diagnosed with severe periodontitis that was associated with CyN. Gene testing showed a novel heterozygous mutation in exon 4 of the ELANE gene (c.538delC, p.Leu180Ser fsX11).

INTERVENTIONS

Based on the clinical findings, we planned to extract the patient's mandibular lateral incisors. Although the tooth extraction was scheduled considering the cyclic variation in neutrophil count, the patient's neutrophil count was 0/μL on the day before the planned extraction. Therefore, granulocyte-colony stimulating factor (G-CSF) was administered to increase the patient's neutrophil count. On the day of the patient's admission for the tooth extraction, she presented with fever (body temperature, 38.5°C), tonsillitis, and stomatitis. The extraction was subsequently delayed, and the patient was administered antibiotics and G-CSF for 4 days. At this time, the neutrophil count increased to 750/μL, and the tooth extraction was carried out safely.

OUTCOMES

The postoperative course was uneventful, and the healing process at the extraction site was excellent.

CONCLUSION

There is a possibility that the periodicity and oscillations of neutrophil count may change with growth in patients with CyN. Therefore, it is important to frequently examine and treat patients with fluctuating neutrophil levels for the management of invasive dental treatment in patients with CyN.

Towards better diagnostic criteria for periodic fever, aphthous stomatitis, pharyngitis and adenitis syndrome

AIM

Periodic fever, aphthous stomatitis, pharyngitis and cervical adenitis (PFAPA) syndrome is the most common cause of a periodic fever in childhood. The exact pathogenesis and the aetiology of PFAPA are still unknown.

METHODS

We conducted a non-systematic review of published articles about PFAPA syndrome and summarised the evidence for diagnostic criteria and treatment options for PFAPA.

RESULTS

The first proposed diagnostic criteria for PFAPA, in addition to periodic fever, included aphthous stomatitis, pharyngitis or cervical lymphadenitis in children younger than five years at the beginning of the symptoms. C-reactive protein (CRP) levels and leucocyte counts increase in most patients during episodes. Recent research reveals that tonsillectomy provides an immediate and long-lasting cure for PFAPA, even in the absence of classic criteria of aphthous stomatitis, pharyngitis or cervical adenitis and in children older than five years.

CONCLUSION

We suggest that PFAPA can be diagnosed in children with at least five regularly occurring fever episodes without any other explanation, even in the absence of aphthous stomatitis, pharyngitis or cervical lymphadenitis and also in children older than five years.

Periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis (PFAPA) syndrome: main features and an algorithm for clinical practice

Periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis (PFAPA) syndrome is a recurrent fever syndrome of early childhood with increasing number of adult-onset cases. Although it is a self-limited disease, it may negatively affect the quality of life. The aim of this review is to present a detailed analysis of PFAPA syndrome and an algorithm for diagnosis, therapeutic options, and evaluation of outcome. A comprehensive literature search was conducted through the Cochrane Library, Scopus, and MEDLINE/PubMed databases. The main topics covered are the epidemiology, clinical manifestations, diagnosis, differential diagnosis, etiopathogenesis, genetics, management, disease course and prognosis, disease in adults, unsolved issues, and unmet needs in PFAPA. The diagnosis of PFAPA is mainly based on clinical classification criteria. The most relevant hypothesis for pathogenesis is that dysregulated immune system in a genetically predisposed individual responds to a yet unidentified trigger in an exaggerated way. The pedigree analyses suggest a genetic background for the disease with an autosomal dominant pattern of inheritance. For management, single-dose corticosteroids during attacks and tonsillectomy remain the most effective therapies, while colchicine is a promising option to decrease attack frequency. There remain unsolved issues in PFAPA such as the exact etiopathogenesis and genetic background, the reason why the inflammation is restricted to the oropharyngeal lymphoid tissue, reasons for clock-work regularity of attacks, and self-limited disease course. There is need for a valid diagnostic criteria set with a high performance for both children and adults and consensus on management of PFAPA.

Cyclic manner of neutropenia in a patient with HAX-1 mutation

Introduction: Severe congenital neutropenia (SCN) includes a group of genetic disorders which cause to arrest of neutrophil maturation. SCN can be associated with heterogenous group of genetic defects in ELANE, GFI1, HAX1, G6PC3, JAGN1, VPS45 or activating mutations in the Wiskott-Aldrich syndrome (WAS) gene. Aim: Here we report a patient who has a HAX1 mutation presented with cyclic manner. Case Report: A 6 year old female patients was admitted with recurrent apthous stomatitis. We followed the patient as cyclic neutropenia according to complete blood count results 2 times for 6 weeks. After persistant neutropenia developed during a severe varicella infection, we analysed HAX1 mutation, the result was interesting and incompatible with reported cyclic neutropenia patients. Conclusion: We suggest that HAX1 deficiency should be thought in patients who have normal neutrophil counts in the between of infections.

Staphylococcus aureus, phagocyte NADPH oxidase and chronic granulomatous disease

Dysfunction of phagocytes is a relevant risk factor for staphylococcal infection. The most common hereditary phagocyte dysfunction is chronic granulomatous disease (CGD), characterized by impaired generation of reactive oxygen species (ROS) due to loss of function mutations within the phagocyte NADPH oxidase NOX2. Phagocytes ROS generation is fundamental to eliminate pathogens and to regulate the inflammatory response to infection. CGD is characterized by recurrent and severe bacterial and fungal infections, with Staphylococcus aureus as the most frequent pathogen, and skin and lung abscesses as the most common clinical entities. Staphylococcus aureus infection may occur in virtually any human host, presumably because of the many virulence factors of the bacterium. However, in the presence of functional NOX2, staphylococcal infections remain rare and are mainly linked to breaches of the skin barrier. In contrast, in patients with CGD, S. aureus readily survives and frequently causes clinically apparent disease. Astonishingly, little is known why S. aureus, which possesses a wide range of antioxidant enzymes (e.g. catalase, SOD), is particularly sensitive to control through NOX2. In this review, we will evaluate the discovery of CGD and our present knowledge of the role of NOX2 in S. aureus infection.

Periodontal and other oral manifestations of immunodeficiency diseases

The list of immunodeficiency diseases grows each year as novel disorders are discovered, classified, and sometimes reclassified due to our ever-increasing knowledge of immune system function. Although the number of patients with secondary immunodeficiencies (SIDs) greatly exceeds those with primary immunodeficiencies (PIDs), the prevalence of both appears to be on the rise probably because of scientific breakthroughs that facilitate earlier and more accurate diagnosis. Primary immunodeficiencies in adults are not as rare as once thought. Globally, the main causes of secondary immunodeficiency are HIV infection and nutritional insufficiencies. Persons with acquired immune disorders such as AIDS caused by the human immunodeficiency virus (HIV) are now living long and fulfilling lives as a result of highly active antiretroviral therapy (HAART). Irrespective of whether the patient's immune-deficient state is a consequence of a genetic defect or is secondary in nature, dental and medical practitioners must be aware of the constant potential for infections and/or expressions of autoimmunity in these individuals. The purpose of this review was to study the most common conditions resulting from primary and secondary immunodeficiency states, how they are classified, and the detrimental manifestations of these disorders on the periodontal and oral tissues.

Severe congenital neutropenias

Severe congenital neutropenias are a heterogeneous group of rare haematological diseases characterized by impaired maturation of neutrophil granulocytes. Patients with severe congenital neutropenia are prone to recurrent, often life-threatening infections beginning in their first months of life. The most frequent pathogenic defects are autosomal dominant mutations in ELANE, which encodes neutrophil elastase, and autosomal recessive mutations in HAX1, whose product contributes to the activation of the granulocyte colony-stimulating factor (G-CSF) signalling pathway. The pathophysiological mechanisms of these conditions are the object of extensive research and are not fully understood. Furthermore, severe congenital neutropenias may predispose to myelodysplastic syndromes or acute myeloid leukaemia. Molecular events in the malignant progression include acquired mutations in CSF3R (encoding G-CSF receptor) and subsequently in other leukaemia-associated genes (such as RUNX1) in a majority of patients. Diagnosis is based on clinical manifestations, blood neutrophil count, bone marrow examination and genetic and immunological analyses. Daily subcutaneous G-CSF administration is the treatment of choice and leads to a substantial increase in blood neutrophil count, reduction of infections and drastic improvement of quality of life. Haematopoietic stem cell transplantation is the alternative treatment. Regular clinical assessments (including yearly bone marrow examinations) to monitor treatment course and detect chromosomal abnormalities (for example, monosomy 7 and trisomy 21) as well as somatic pre-leukaemic mutations are recommended.

Granulocyte colony-stimulating factor alters the systemic metabolomic profile in healthy donors

INTRODUCTION

Peripheral blood stem cells mobilized by granulocyte colony-stimulating factor (G-CSF) from healthy donors are commonly used for allogeneic stem cell transplantation. The effect of G-CSF administration on global serum metabolite profiles has not been investigated before.

OBJECTIVES

This study aims to examine the systemic metabolomic profiles prior to and following administration of G-CSF in healthy adults.

METHODS

Blood samples were collected from 15 healthy stem cell donors prior to and after administration of G-CSF 10 µg/kg/day for 4 days. Using a non-targeted metabolomics approach, metabolite levels in serum were determined using ultrahigh performance liquid chromatography-tandem mass spectrometry and gas chromatography/mass spectrometry.

RESULTS

Comparison of the metabolite profiles of donors before and after G-CSF treatment revealed 239 metabolites that were significantly altered. The major changes of the metabolite profiles following G-CSF administration included alteration of several fatty acids, including increased levels of several medium and long-chain fatty acids, as well as polyunsaturated fatty acids; while there were lower levels of other lipid metabolites such as phospholipids, lysolipids, sphingolipids. Furthermore, there were significantly lower levels of several amino acids and/or their metabolites, including several amino acids with known immunoregulatory functions (methionine, tryptophan, valine). Lastly, the levels of several nucleotides and nucleotide metabolites (guanosine, adenosine, inosine) were also decreased after G-CSF administration, while methylated products were increased. Some of these altered products/metabolites may potentially have angioregulatory effects whereas others may suggest altered intracellular epigenetic regulation.

CONCLUSION

Our results show that G-CSF treatment alters biochemical serum profiles, in particular amino acid, lipid and nucleotide metabolism. Additional studies are needed to further evaluate the relevance of these changes in healthy donors.

Approach to the patient with neutropenia in childhood

Neutrophils have an important role in host defense and acute inflammation. It is well known that susceptibility to infection increases when the neutrophil count is low. Neutropenia were classified as mild, moderate and severe according to the neutrophil counts, or acute and chronic depending on the duration of neutropenia, or congenital and acquired according to the mechanism. The patients with neutropenia are clinically different due to underlying mechanism, they have life- threatening infections or no infection may be observed. The most common cause of acquired neutropenia is viral infection, followed by drugs and autoimmune neutropenia. Congenital neutropenia are usually diagnosed by acute and life- threatening invasive bacterial and fungal infections. Immune system disorders and other systemic abnormalities may be accompanied or not. Recent years, novel single gen defects causing congenital neutropenia were defined through advanced genetic techniques. Molecular diagnosis is useful for risk stratification, choice of therapy and prognosis on follow- up. This review was prepared for pediatricians as a guide focused on approach neutropenia, which tests should be performed and when should be referred to a specialist.

Full-Arch Rehabilitation of a Patient With Cyclic Neutropenia

The purpose of this report is to discuss the treatment of a patient with cyclic neutropenia. This patient presented with flared teeth, thin alveolar bone, and mobile teeth. A staged approach was used to remove her teeth, augment the bone, use immediate fixed provisional to determine the type of final prostheses, and ultimately to use cone-shaped overdenture attachments to retain her final prostheses. The result was rehabilitation of the patient with esthetic full-arch fixed-removable dentures with no adverse sequelae in this patient with this systemic disease.

Cyclic neutropenia with a novel gene mutation presenting with a necrotizing soft tissue infection and severe sepsis: case report

BACKGROUND

Cyclic neutropenia is a rare disease. We report a 31-month-old girl with congenital cyclic neutropenia with a novel mutation in the ELANE gene who developed an acute necrotizing soft-tissue infection on her left axillary legion.

CASE PRESENTATION

A 31-month-old girl was admitted to our pediatric emergency room because of a necrotizing soft tissue infection of the left axillary area. The infection progressed rapidly and resulted in septic shock. Despite a medical treatment and surgical debridement, the sepsis was not controlled, and severe inflammation developed. After applying of negative-pressure wound therapy, her clinical symptoms improved. Finally, she was diagnosed with cyclic neutropenia with a novel genetic mutation. One month after admission, she was discharged with a completely recovered wound and no need for skin grafting.

CONCLUSION

Both adequate medical treatment and effective control of the source of infection are critically important to reduce morbidity in such complex cases of necrotizing fasciitis as appeared in an immunocompromised pediatric patient.

Autoinflammatory syndromes

Autoinflammatory syndromes comprise a diagnostically challenging group of systemic inflammatory disorders uniquely related by (1) dysregulation of innate immunity, (2) inflammasome activation, (3) dramatic clinical features (high fevers, neutrophilic rashes, and bone or synovial involvement), (4) impressive acute phase responses, and (5) effective treatment with cytokine inhibitors. This review details some of the more common autoinflammatory disorders, their distinguishing features and dermatologic manifestations, and how an accurate diagnosis can be established in patients presenting with periodic or intermittent febrile disorders.

Familial mediterranean fever: a fascinating model of inherited autoinflammatory disorder

BACKGROUND

Familial Mediterranean fever (FMF) is a rare inherited autosomal recessive autoinflammatory disorder characterized by recurrent and self-limited episodes of fever and painful serositis, lasting 1-3 days. FMF occurs almost exclusively among ethnic groups of the Mediterranean basin, although cases have also been found in Japan and Korean populations. Diagnosis is based on clinical features, response to colchicine and genetic analysis. Novel drugs are emerging, allowing better management of colchicine-resistant/colchicine-intolerant patients. This review aims to attract the attention of the readers on differential diagnosis and management of patients with FMF.

METHODS

The current state-of-the-art on FMF is outlined, with respect to epidemiological, genetic, pathophysiological and therapeutic characteristics, based on critical analysis of solid scientific literature.

RESULTS

FMF is more frequent than it was thought before. The phenotypic expression of M694V is more severe than that of V726A. Patients with M694V/M694V homozygosity are exposed to a higher risk of developing renal amyloidosis, arthritis, dermatologic and oral lesions, higher fever and more frequent painful attacks. Life-long therapy with colchicine (1·0-2·4 mg/day) is effective and safe to prevent recurrent attacks and renal amyloidosis and to reverse proteinuria. In nonresponder patients, alternative novel approaches include interleukin-1 receptor antagonist anakinra and the interleukin-1 decoy receptor rilonacept.

CONCLUSIONS

The prognosis of FMF is normal if AA amyloidosis is prevented. Colchicine remains the first-line therapy to treat pain and prevent amyloidosis. A follow-up should include clinical evaluation, therapeutic adjustments, measurement of serum amyloid A and proteinuria.

Prolonged and recurrent fevers in children

Some children referred for prolonged fever are actually not having elevated temperatures; the approach here requires dissection of the history and correction of health misperceptions. Others have well-documented fevers associated with clinical, laboratory, or epidemiologic findings that should point to a specific diagnosis. "Fever-of-Unknown-Origin" (FUO) is the clinical scenario of daily fever for ≥ 14 days that defies explanation after a careful history, physical examination, and basic laboratory tests. The diagnostic approach requires a meticulous fever diary, serial clinical and laboratory evaluations, vigilance for the appearance of new signs and symptoms, and targeted investigations; the pace of the work-up is determined by the severity of the illness. Approximately half of children with FUO will have a self-limited illness and will never have a specific diagnosis made; the other half will ultimately be found to have, in order, infectious, inflammatory, or neoplastic conditions. Irregular, intermittent, recurrent fevers in the well-appearing child are likely to be sequential viral illnesses. Monogenic autoinflammatory diseases should be considered in those who do not fit the picture of recurrent infections and who do not have hallmarks of immune deficiency. Stereotypical febrile illnesses that recur with clockwork periodicity should raise the possibilities of cyclic neutropenia, if the cycle is approximately 21 days, or periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome, the most common periodic fever in childhood.

How to approach neutropenia

Neutropenia is defined as the reduction in the absolute number of neutrophils in the blood circulation. Acute neutropenia is a relatively frequent finding, whereas disorders of production of neutrophils are quite rare. Acute neutropenia is often well tolerated and normalizes rapidly. Neutropenia arising as a result of underlying hematologic disorders is far more significant. Such a patient may be at risk for infectious complications and will likely require a thorough investigation. Acute neutropenia evolves over a few days and occurs when neutrophil use is rapid and production is impaired. Chronic neutropenia may last for 3 months or longer and is a result of reduced production, increased destruction, or excessive splenic sequestration of neutrophils. Neutropenia may be classified by whether it arises secondarily to causes extrinsic to BM myeloid cells, which is common; as an acquired disorder of myeloid progenitor cells, which is less frequent; or as an intrinsic defect arising from impaired proliferation and maturation of myeloid progenitor cells in the BM, which is rare. Severe neutropenia with absolute neutrophil counts below 500/μL increases susceptibility to bacterial or fungal infections. Multiple disorders of severe congenital neutropenia have been found by the discovery of genetic defects affecting differentiation, adhesion, and apoptosis of neutrophil precursors. Elucidation of the multiple genetic defects have provided insight into the biology of the cell involving membrane structures, secretory vesicles, mitochondrial metabolism, ribosome biogenesis, transcriptional regulation, and cytoskeletal dynamics, as well as the risk for myelodysplasia and acute myeloid leukemia.

Neonatal neutropenia: what diagnostic evaluation is needed and when is treatment recommended?

Neutropenia is a relatively frequent finding in the neonatal intensive care unit, particularly in very low birth weight neonates during the first week of life. Healthy term and preterm neonates have blood neutrophil counts within the same basic range as adults, but their neutrophil function, and their neutrophil kinetics during infection, differ considerably from those of adults. Neutrophil function of neonates, particularly preterm neonates, is less robust than that of adults and might also contribute to the increase in propensity to infection. In premature infants, early-onset neutropenia is correlated with sepsis, maternal hypertension, intrauterine growth restriction, severe asphyxia, and periventricular haemorrhage, and might be associated with an increase in the incidence of early-onset sepsis, nosocomial infection, and Candida colonisation. Some varieties of neutropenia in the NICU are very common and others are extremely rare. The most common causes of neutropenia in the NICU have an underlying cause that is often evident, and require little diagnostic evaluation. Unlike, persistent neutropenia should prompt evaluation even if it is of moderate severity. The laboratory tests to consider are those that provide a specific diagnosis. The first tests that should be ordered are a blood film, a complete blood count on the mother, and, if her blood neutrophil concentration is normal, maternal neutrophil antigen typing and an anti-neutrophil antibody screen. A bone marrow biopsy can be useful in cases with prolonged, unusual, or refractory neutropenia. Various treatments have been proposed as means of enhancing neutrophil production and function in preterm infants. Both recombinant granulocyte stimulating factor and recombinant granulocyte macrophage-colony-stimulating factor have been tried with variable success. Intravenous immunoglobulin, corticosteroids, granulocyte transfusions, and gamma interferon did not show a clear adequate beneficial role for the therapy of neonatal neutropenia.

Hematological interventions in NICU care: the use of rEpo, IVIG, and rG-CSF

This article focuses on the use of rEpo, IVIG, and rG-CSF in the NICU. It discusses the most recent studies and the most definitive and clinically relevant evidence, rather than summarizing all published studies. The last section was written for NICU practice groups that choose to use any of these medications and are seeking a consistent approach for doing so. The section provides the author's approach to the use of rEpo, IVIG, and rG-CSF, revealing personal preferences, interpretations, and experiences, and is based on the dictum, "if you are going to use it, use it the same way each time."

[Severe congenital neutropenia: analysis of clinical features, diagnostic methods, treatment and long-term outcome]

INTRODUCTION

Severe congenital neutropenia (SCN), a heterogeneous condition with onset at early ages, is characterised by primary myelopoiesis failure with an absolute neutrophil count (ANC) < 0.5 x10(9)/L, severe infections and risk of leukaemic transformation.

OBJECTIVE

The aim of the study was to ascertain the long term outcome of patients with SCN.

MATERIAL AND METHODS

The clinical features, diagnostic methods, treatment and outcome of 11 patients with SCN were analysed.

RESULTS

The median age at diagnosis was 4 months (range: 3 days-12 years). The primary clinical manifestation was severe infection. Median ANC at diagnosis: 0.2 x 10(9)/L (range: 0-0.37). Bone marrow aspirate showed maturation arrest at promyelocyte stage in all cases. Genetic studies revealed 3 mutations, two in ELA-2 gene and 1 in G6PC3 gene, showing a correlation between genotype and phenotype. Granulocyte Colony Stimulating Factor (G-CSF) was the first-line treatment in 9 patients; six of whom showed a good response at doses between 5 and 15 μg/kg/day for 3-7 days/week. The remaining 3 patients failed to respond to G-CSF and allogeneic stem cell transplantation (SCT) was indicated. Furthermore, SCT was the treatment of choice in two cases. Median follow-up of the cohort was 5 years (range: 1-10 years) with 100% survival and no cases of leukaemic transformation.

CONCLUSIONS

We conclude that genetic study is useful for establishing a correlation between genotype and phenotype. The treatment of choice for SCN is G-CSF to which 2/3 of patients should respond; while SCT is reserved for cases of poor response or those evolving to myelodysplastic syndrome (MDS) or leukaemia; thus close follow-up of this condition is essential.

Educational paper: Defects in number and function of neutrophilic granulocytes causing primary immunodeficiency

The neutrophilic granulocyte (neutrophil) is the most important cellular component of the innate immune system. A total absence of neutrophils or a significant decrease in their number leads to severe immunodeficiency. A mature neutrophil, released from the bone marrow, should be able to migrate from the blood towards the tissues, following a chemotactic gradient to a pathogen. In order to be neutralized, this pathogen has to be recognized, phagocytosed, and destroyed by lytic enzymes contained in the neutrophil's granules and reactive oxygen species formed by the enzyme complex NADPH oxidase. Rare genetic defects leading to the loss of each one of these biological properties of the neutrophil have been described and are associated with immunodeficiency. This review provides a summary of the normal development and biological functions of neutrophils and describes the diseases caused by defects in neutrophil number and function.