De Novo Deep Intron ELANE Mutation Resulting in Severe Congenital Neutropenia.

Severe congenital neutropenia (SCN) comprises a diverse range of rare hematological disorders characterized by recurrent, often life-threatening infections that manifest within the first months of life. Mutations in the ELANE gene are the most prevalent cause of SCN. While over 230 mutations in ELANE have been documented, including substitutions, frameshifts, nonsense mutations, and splice site alterations, the occurrence of deep intronic mutations has not been previously reported. Herein, we present the case of a young girl who exhibited recurrent fever, respiratory infections, skin abscesses, and gingivitis shortly after birth. Laboratory analysis revealed markedly diminished neutrophil levels alongside elevated monocyte and eosinophil counts. Bone marrow examination disclosed a halt in myelopoiesis maturation. ELANE gene full-length sequencing identified a novel de novo deep intron mutation in ELANE (c.598 + 79G > T), subsequently confirmed by Sanger sequencing. cDNA sequencing of the patient demonstrated aberrant gene splicing. Utilizing a mini-gene splicing assay for ELANE intronic variants, we identified a mutant ELANE allele (c.597 + 1_597 + 83ins) leading to the creation of a premature termination codon (p.Gly200ValfsTer40). Confocal microscopy revealed heightened expression of myeloperoxidase and neutrophil elastase in the patient, suggesting a potential role for the unfolded protein response in the pathogenesis of the deep intron ELANE mutation. In summary, our findings illustrate the first reported instance of de novo deep intron ELANE mutations associated with SCN, underscoring the importance of exploring deep intronic regions in SCN patients lacking identifiable disease-causing gene mutations.

Oral health management in children with severe congenital neutropenia with periodontitis: Case report.

RATIONALE: Severe congenital neutropenia (SCN) is a rare and heterogeneous genetic disease. By describing the diagnosis and treatment of a child with SCN and periodontitis, this case provides a reference for the oral health management of a child with SCN and periodontitis. PATIENT CONCERNS: We describe a boy with clinical manifestations of oral bleeding, neutropenia, recurrent fever, and other recurrent infections. The absolute neutrophil count (ANC) was <0.50 × 109/L most of the time. Morphological examination of bone marrow cells showed active granulocyte hyperplasia and dysmaturation. DIAGNOSES: According to the clinical manifestations, hematological examination and gene detection results, the child was diagnosed as SCN with chronic periodontitis. INTERVENTIONS: Periodontal treatment was performed after informed consent was obtained from the child guardian. These included supragingival and subgingival cleaning, hydrogen peroxide and saline irrigation, placement of iodoglycerin in the gingival sulcus, and oral hygiene instruction. Hematopoietic stem cell transplantation (HSCT) was performed later. OUTCOMES: One month after initial periodontal treatment, oral hygiene was well maintained and gingival swelling had subsided. Probing depth (PD) index on periodontal probing and bleeding was significantly reduced. However, there was no significant change in blood routine and other indicators before and after periodontal treatment. CONCLUSION: Once SCN is diagnosed, individualized treatment plans can be developed according to the characteristics of the disease and its impact on oral health, which can effectively control the interaction between SCN and periodontal disease and reduce the occurrence of serious infection.

Discerning clinicopathological features of congenital neutropenia syndromes: an approach to diagnostically challenging differential diagnoses.

The congenital neutropenia syndromes are rare haematological conditions defined by impaired myeloid precursor differentiation or function. Patients are prone to severe infections with high mortality rates in early life. While some patients benefit from granulocyte colony-stimulating factor treatment, they may still face an increased risk of bone marrow failure, myelodysplastic syndrome and acute leukaemia. Accurate diagnosis is crucial for improved outcomes; however, diagnosis depends on familiarity with a heterogeneous group of rare disorders that remain incompletely characterised. The clinical and pathological overlap between reactive conditions, primary and congenital neutropenias, bone marrow failure, and myelodysplastic syndromes further clouds diagnostic clarity.We review the diagnostically useful clinicopathological and morphological features of reactive causes of neutropenia and the most common primary neutropenia disorders: constitutional/benign ethnic neutropenia, chronic idiopathic neutropenia, cyclic neutropenia, severe congenital neutropenia (due to mutations in ELANE, GFI1, HAX1, G6PC3, VPS45, JAGN1, CSF3R, SRP54, CLPB and WAS), GATA2 deficiency, Warts, hypogammaglobulinaemia, infections and myelokathexis syndrome, Shwachman-Diamond Syndrome, the lysosomal storage disorders with neutropenia: Chediak-Higashi, Hermansky-Pudlak, and Griscelli syndromes, Cohen, and Barth syndromes. We also detail characteristic cytogenetic and molecular factors at diagnosis and in progression to myelodysplastic syndrome/leukaemia.

Genetic backgrounds and clinical characteristics of congenital neutropenias in Israel.

BACKGROUND: Congenital neutropenias are characterized by severe infections and a high risk of myeloid transformation; the causative genes vary across ethnicities. The Israeli population is characterized by an ethnically diverse population with a high rate of consanguinity. OBJECTIVE: To evaluate the clinical and genetic spectrum of congenital neutropenias in Israel. METHODS: We included individuals with congenital neutropenias listed in the Israeli Inherited Bone Marrow Failure Registry. Sanger sequencing was performed for ELANE or G6PC3, and patients with wild-type ELANE/G6PC3 were referred for next-generation sequencing. RESULTS: Sixty-five patients with neutropenia were included. Of 51 patients with severe congenital neutropenia, 34 were genetically diagnosed, most commonly with variants in ELANE (15 patients). Nine patients had biallelic variants in G6PC3, all of consanguineous Muslim Arab origin. Other genes involved were SRP54, JAGN1, TAZ, and SLC37A4. Seven patients had cyclic neutropenia, all with pathogenic variants in ELANE, and seven had Shwachman-Diamond syndrome caused by biallelic SBDS variants. Eight patients (12%) developed myeloid transformation, including six patients with an unknown underlying genetic cause. Nineteen (29%) patients underwent hematopoietic stem cell transplantation, mostly due to insufficient response to treatment with granulocyte-colony stimulating factor or due to myeloid transformation. CONCLUSIONS: The genetic spectrum of congenital neutropenias in Israel is characterized by a high prevalence of G6PC3 variants and an absence of HAX1 mutations. Similar to other registries, for 26% of the patients, a molecular diagnosis was not achieved. However, myeloid transformation was common in this group, emphasizing the need for close follow-up.

Successful Management of Neutropenic Sepsis Is Key to Better Survival of Patients With Blood Cancer in Sri Lanka: Real-World Data From the Resource-Limited Setting.

PURPOSE: Sepsis is the main cause of nonrelapse mortality, and there are no published data on applicability of supportive care protocols from high-income countries such as Sri Lanka. The aim of the study was to investigate management and mortality of neutropenic episodes among Hemato-Oncology patients. MATERIALS AND METHODS: Retrospective analysis of clinical characteristics, management, morbidity, and mortality of neutropenic Hemato-Oncology patients presented to the Lanka Hospital Blood Cancer Centre from January 1, 2019 to December 31, 2019 was performed. RESULTS: A total of 169 neutropenic episodes were identified; 115 (68%) of such episodes were related to chemotherapy. Acute leukemia, lymphoproliferative disorders, and plasma cell disorders accounted for 23%, 69%, and 8% of patients, respectively. The median age of patients who had sepsis was 56 years, whereas that of those who had no sepsis was 53 years (P = .49). The median time to neutropenia was 9 days for those in the sepsis group compared with 8 days in the group that had no sepsis (0.64). The median neutrophil count in the group that had sepsis was 0.06, whereas it was 0.69 in the group that had no sepsis (P ≤ .05). The median time to commencement of antibiotics was 20 minutes. CONCLUSION: To our knowledge, this is the only documented study related to outcome and successful applicability of western supportive care protocols to Sri Lankan patients with neutropenia. In this study, we have shown that neutropenic sepsis can be successfully managed in the setting of limited resources with service development, following guidelines and staff training.

Efficacy and safety of coadministration of venetoclax and anti-fungal agents under therapeutic drug monitor in unfit acute myeloid leukemia and high-risk myelodysplastic syndrome with neutropenia: a single-center retrospective study.

Unfit acute myeloid leukemia and high-risk myelodysplastic syndrome patients with prolonged neutropenia demand coadministration of venetoclax and azoles. However, venetoclax dosing under drug-drug interaction with azoles remains controversial. Therapeutic drug monitoring (TDM) is expected to guide drug dosage adjustments. We retrospectively enrolled 17 patients under this coadministration and TDM. Venetoclax dosages were interfered when inappropriate drug concentrations appeared. The primary endpoints were objective response and adverse events. Venetoclax concentration outliers were more frequently evaluated before than after dose adjustment (Cmax 60.87% vs. 0.00%, p < .0001). MRD negativity rate was higher in patients staying within reference range than those having outliers (90.91% vs. 33.33%, p = .028). Objective response rate was 100%. Hematologic adverse events included neutropenia (93.3%), febrile neutropenia (53.3%), and thrombocytopenia (81.3%). Median time to neutropenia and thrombocytopenia recovery was 20 (14-32) and 16.5 (6-34) days, respectively. No invasive fungal and other life-threatening infections were observed.

Metagenomic next-generation sequencing in detecting pathogens in pediatric oncology patients with suspected bloodstream infections.

BACKGROUND: Studies on mNGS application in pediatric oncology patients, who are at high risk of infection, are quite limited. METHODS: From March 2020 to June 2022, a total of 224 blood samples from 195 pediatric oncology patients who were suspected as bloodstream infections were enrolled in this study. Their clinical and laboratory data were retrospectively reviewed, and the diagnostic performance of mNGS was assessed. RESULTS: Compared to the reference tests, mNGS showed significantly higher sensitivity (89.8% vs 32.5%, P < 0.001) and clinical agreement (76.3% vs 51.3%, P < 0.001) in detecting potential pathogens and distinguishing BSI from non-BSI. Especially, mNGS had an outstanding performance for virus detection, contributing to 100% clinical diagnosed virus. Samples from patients with neutropenia showed higher incidence of bacterial infections (P = 0.035). The most identified bacteria were Escherichia coli, and the overall infections by gram-negative bacteria were significantly more prevalent than those by gram-positive ones (90% vs 10%, P < 0.001). Overall, mNGS had an impact on the antimicrobial regimens' usage in 54.3% of the samples in this study. CONCLUSIONS: mNGS has the advantage of rapid and effective pathogen diagnosis in pediatric oncology patients with suspected BSI, especially for virus. IMPACT: Compared with reference tests, mNGS showed significantly higher sensitivity and clinical agreement in detecting potential pathogens and distinguishing bloodstream infections (BSI) from non-BSI. mNGS is particularly prominent in clinical diagnosed virus detection. The incidence of bacterial infection was higher in patients with neutropenia, and the overall infection rate of Gram-negative bacteria was significantly higher than that of Gram-positive bacteria. mNGS affects the antimicrobial regimens' usage in more than half of patients.

Neutropenic ulcers in oncology: terminology, diagnosis, and management.

Neutropenic ulcerations are characterized by mucosal ulcerations which occur in the presence of neutropenia, suggesting a direct link between neutropenia and mucosal ulceration. An oral ulcer can be labeled as "neutropenic" only if the patients have primary (typically congenital) or secondary neutropenia, and neutropenia is the sole causative factor. Oral mucosal ulcers observed in patients undergoing oncologic therapy may also be termed as "neutropenic ulcers", but the pathogenesis of these oral ulcers more likely involves mucosal events related to trauma, microbial factors, and direct cytotoxicity. In cancer patients, the early appearance of oral ulcers is often attributed to oral mucositis which is a condition primarily caused by the direct mucosal cytotoxicity of chemotherapeutic agents and radiation therapy. Oral ulcers that develop later during or after active cancer therapy may result from intraoral trauma and typically manifest on non-keratinized areas of the oral mucosa which are more susceptible to mucosal damage. In patients undergoing chemotherapy, factors such as disturbances in mucosal barrier function as well as bone marrow suppression lead to reduced neutrophil count and function, and can contribute to the development of oral ulcers. While the etiology of oral ulcers in cancer therapy receiving patients can vary, it is important to emphasize that the host's response plays a crucial role in the progression and repair process of these lesions. This narrative review presents the etiopathogenesis, clinical presentation, and potential management approaches for oral ulcerations in neutropenic patients, with a particular focus on clarifying the usage of the term "neutropenic ulcer" since this term lacks diagnostic specificity and can be misleading in clinical practice regarding the underlying causes and treatment strategies.

[Time to Antibiotics (TTA) - Reassessment from the German Working Group for Fever and Neutropenia in Children and Adolescents (DGPI/GPOH)]. / Time to Antibiotics (TTA) ­ Überlegungen der Arbeitsgruppe Fieber bei Granulozytopenie im Kindes- und Jugendalter (GPOH/DGPI) zu einer Neubewertung.

BACKGROUND: The current German guidance from 2016 recommends a Time to Antibiotics (TTA) of<60 min in children and adolescents with febrile neutropenia (FN). METHODS: Critical analysis of available studies and recent meta-analyses, and discussion of the practical consequences in the FN working group of the German Societies for Paediatric Oncology and Haematology and Paediatric Infectious Diseases. RESULTS: The available evidence does not support a clinically significant outcome benefit of a TTA<60 min in all paediatric patients with FN. Studies suggesting such a benefit are biased (mainly triage bias), use different TTA definitions and display further methodical limitations. In any case, a TTA<60 min remains an essential component of the 1st hour-bundle in paediatric cancer patients with septic shock or sepsis with organ dysfunction. CONCLUSION: Provided that all paediatric FN patients receive a structured medical history and physical examination (including vital signs) by experienced and trained medical personnel in a timely fashion, and provided that a sepsis triage and management bundle is established and implemented, a TTA lower than 3 hours is sufficient and reasonable in stable paediatric cancer patients with FN.

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.

Outcome prediction in pediatric fever in neutropenia: Development of clinical decision rules and external validation of published rules based on data from the prospective multicenter SPOG 2015 FN definition study.

BACKGROUND: Fever in neutropenia (FN) remains a serious complication of childhood cancer therapy. Clinical decision rules (CDRs) are recommended to help distinguish between children at high and low risk of severe infection. The aim of this analysis was to develop new CDRs for three different outcomes and to externally validate published CDRs. PROCEDURE: Children undergoing chemotherapy for cancer were observed in a prospective multicenter study. CDRs predicting low from high risk infection regarding three outcomes (bacteremia, serious medical complications (SMC), safety relevant events (SRE)) were developed from multivariable regression models. Their predictive performance was assessed by internal cross-validation. Published CDRs suitable for validation were identified by literature search. Parameters of predictive performance were compared to assess reproducibility. RESULTS: In 158 patients recruited between April 2016 and August 2018, 360 FN episodes were recorded, including 56 (16%) with bacteremia, 30 (8%) with SMC and 72 (20%) with SRE. The CDRs for bacteremia and SRE used four characteristics (type of malignancy, severely reduced general condition, leucocyte count <0.3 G/L, bone marrow involvement), the CDR for SMC two characteristics (severely reduced general condition and platelet count <50 G/L). Eleven published CDRs were analyzed. Six CDRs showed reproducibility, but only one in both sensitivity and specificity. CONCLUSIONS: This analysis developed CDRs predicting bacteremia, SMC or SRE at presentation with FN. In addition, it identified six published CDRs that show some reproducibility. Validation of CDRs is fundamental to find the best balance between sensitivity and specificity, and will help to further improve management of FN.

[Early detection of WHIM symdrome. A case report]. / Identificación temprana de síndrome de WHIM. Informe de un caso.

BACKGROUND: WHIM syndrome corresponds to an inborn error of innate and intrinsic immunity, characterized by: warts (Warts), Hypogammaglobulinemia, Infections and Myelocathexis, for its acronym in English. CASE REPORT: 4-year-old male, with severe neutropenia and B-cell lymphopenia from birth, without severe infections or warts; the panel genetic sequencing study of primary immunodeficiencies with the CXCR4 c.1000C>T (p.Arg334*) variant, which is associated with WHIM syndrome. CONCLUSIONS: The diagnosis of severe neutropenia from birth should include the search for inborn errors of immunity, through genetic sequencing studies, especially in asymptomatic or oligosymptomatic patients.

ANTECEDENTES: El síndrome WHIM corresponde a un error innato de la inmunidad innata e intrínseca, caracterizada por verrugas (Warts), hipogammaglobulinemia, infecciones y mielocatexis, por sus siglas en inglés. REPORTE DE CASO: Paciente masculino de 4 años, con neutropenia severa y linfopenia de células B desde el nacimiento, sin infecciones severas ni verrugas. El estudio de secuenciación genética informó la variante CXCR4 c.1000C>T (p.Arg334*), relacionada con el síndrome de WHIM. CONCLUSIÓN: El diagnóstico de neutropenia severa desde el nacimiento debe incluir la búsqueda de errores innatos de la inmunidad, mediante estudios de secuenciación genética, especialmente en pacientes asintomáticos u oligosintomáticos.

Platelet count and dose, but not comorbidities, predict severe neutropenia in cabazitaxel-treated prostate cancer patients: A retrospective observational study.

OBJECTIVE: To determine the safety of cabazitaxel and predictors of severe neutropenia caused by cabazitaxel in a patient population that includes those with comorbidities. MATERIALS AND METHODS: Of 42 prostate cancer patients treated with cabazitaxel at Osaka Medical and Pharmaceutical University Hospital between September 2014 and June 2022, 33 were included in this study, whereas 6 patients who were outpatients and 3 who were discharged early within 7 days upon patient request were excluded. Logistic regression analysis was used to examine predictors of severe neutropenia. RESULTS: Of the 33 eligible patients, 24 had comorbidities, with hypertension being the most common (n = 19), followed by dyslipidemia (n = 14) and diabetes (n = 11). There was no statistically significant difference in the rate of severe neutropenia due to any of the comorbidities, depending on the presence or absence of the comorbidity. However, the rate of severe neutropenia was significantly higher in patients with baseline platelet levels < 22.4×104/µL and those receiving cabazitaxel doses > 34 mg/body. In the final model adjusted for age, body mass index, C-reactive protein, and monocyte count, lower baseline platelet levels and higher doses of cabazitaxel were also predictors of the development of severe neutropenia. CONCLUSION: Comorbidities such as hypertension, dyslipidemia, diabetes mellitus, cerebrovascular disease, chronic kidney disease, liver dysfunction, and cardiac disease did not affect the incidence of severe neutropenia in patients receiving cabazitaxel. The baseline platelet count and the dose of cabazitaxel were also suggested to be markers for the development of severe neutropenia.

[Consensus on clinical diagnosis, treatment, and prevention of chemotherapy-induced neutropenia in China (2023 edition)].

Chemotherapy-induced neutropenia (CIN) is a common hematological adverse events and dose-limiting toxicities of chemotherapy. CIN may lead to dose reduction and delay of chemotherapeutic agents, febrile neutropenia and severe infection, which results in increased treatment cost, reduced efficacy of chemotherapy, and even life-threatening morbidities. Assessment of risk of CIN, early detection of FN and infection, and proper prevention and treatment play a crucial role in reducing the occurrence of CIN-related morbidities, improving patient treatment safety and anticancer efficacy. Based on evidence and expert opinion, the expert committee of Chinese Anti-Cancer Association issued "the consensus on diagnosis and treatment of chemotherapy-induced neutropenia in China (2023 edition)", which is an update version of the 2019 edition, aiming to provide reference for the diagnosis and treatment of CIN for Chinese oncologists.

Neutropenia: A Brief Review.

Neutropenia is one of the most common abnormalities on complete blood count encountered in pediatric clinical practice. It causes anxiety in the pediatric clinician as well as in the patient and their family. Neutropenia can be inherited or acquired. Acquired neutropenia is much more common than inherited neutropenia. Acquired neutropenia self-resolves after the offending cause is removed, and therefore, most acquired neutropenia can be managed by primary care physicians, unless they are associated with severe infections. In contrast, inherited neutropenia needs to be managed in collaboration with the hematologist. [Pediatr Ann. 2023;52(6):e238-e241.].