Leukopenia associated with lamotrigine initiation after COVID-19 vaccine booster: A case report and literature review.

Adverse lamotrigine effects are more likely with concomitant use of antiepileptic drugs, rapid dose titration, and multiple drug use, highlighting the importance of measuring its concentration. Here, lamotrigine was administered the day after the third mRNA vaccination to a 20-year-old bipolar woman with these risk factors. Leukopenia occurred on day 12 without rapid concentration increase, but leukocytes gradually recovered after 22 weeks without discontinuation of lamotrigine. The second mRNA vaccination did not induce leukopenia. Possibly, a synergetic immune response to simultaneous vaccination and lamotrigine caused leukopenia, which recovered as the response weakened. Lamotrigine initiation immediately after mRNA vaccination may be a leukopenia risk factor.

Bacterial virulence plays a crucial role in MRSA sepsis.

Bacterial sepsis is a major global cause of death. However, the pathophysiology of sepsis has remained poorly understood. In industrialized nations, Staphylococcus aureus represents the pathogen most commonly associated with mortality due to sepsis. Because of the alarming spread of antibiotic resistance, anti-virulence strategies are often proposed to treat staphylococcal sepsis. However, we do not yet completely understand if and how bacterial virulence contributes to sepsis, which is vital for a thorough assessment of such strategies. We here examined the role of virulence and quorum-sensing regulation in mouse and rabbit models of sepsis caused by methicillin-resistant S. aureus (MRSA). We determined that leukopenia was a predictor of disease outcome during an early critical stage of sepsis. Furthermore, in device-associated infection as the most frequent type of staphylococcal blood infection, quorum-sensing deficiency resulted in significantly higher mortality. Our findings give important guidance regarding anti-virulence drug development strategies for the treatment of staphylococcal sepsis. Moreover, they considerably add to our understanding of how bacterial sepsis develops by revealing a critical early stage of infection during which the battle between bacteria and leukocytes determines sepsis outcome. While sepsis has traditionally been attributed mainly to host factors, our study highlights a key role of the invading pathogen and its virulence mechanisms.

Roseola Infantum During the COVID-19 Pandemic.

INTRODUCTION: Roseola infantum is always considered to be among the differential diagnosis of young patients with fever and leukopenia whom to be strictly isolated with the preliminary diagnosis of COVID-19 until otherwise proven during the pandemic. RESULTS: Human herpes virus-6 (HHV-6) polymerase chain reaction (PCR) blood test was performed in 4 of 7 patients with a clinical diagnosis of roseola infantum and all found to be HHV-6 PCR positive. The most striking laboratory finding in all patients was leukopenia. HHV-6 PCR tests were found to be positive. Severe acute respiratory syndrome coronavirus-2 testing were found to be negative in all patients. CONCLUSION: During the peak of the pandemic, children continued to present with fever because of viral infections other than COVID-19.

Clinical Implications of Hematologic and Hemostatic Abnormalities in Children With COVID-19.

Leukopenia, thrombocytopenia, elevated D-dimer, and prolonged prothrombin time are considered poor prognostic factors in adults with acute Coronavirus Disease 2019. The prognostic significance of these abnormalities among pediatric patients remains underreported in the literature. This retrospective cohort study evaluates the prognostic implications of hematologic and hemostatic derangements in patients younger than 22-years-of-age who were admitted to a tertiary-care referral institution for management of acute Coronavirus Disease 2019 infection. Leukopenia and thrombocytopenia were identified as independent prognostic factors of disease severity. Although the majority of children, with available results, had elevated D-dimer or prolonged prothrombin time upon initial presentation, these markers were not found to be associated with the development of severe clinical complications.

Nudix hydrolase 15 (NUDT15) loss-of-function variants in an Australian inflammatory bowel disease population.

BACKGROUND: Thiopurine-related adverse events such as leukopenia, liver dysfunction and pancreatitis are associated with variants in the NUDT15 gene. Loss-of-function (low or no enzyme activity) alleles are more common in Asian and Hispanic populations. The prevalence of these variants in the Australian inflammatory bowel disease (IBD) population has not yet been reported. AIM: To evaluate the presence of NUDT15 loss-of-function alleles *2,*3,*9 in the Australian IBD population. METHODS: The NUDT15 screening cohort included 423 IBD patients from Brisbane, Australia. Study patients were recruited by: (i) retrospective review of clinical charts for thiopurine-related severe adverse events; (ii) pathology data (white blood cell (WBC) and neutrophil counts). NUDT15 genotyping was performed using polymerase chain reaction (PCR)-high-resolution melt (HRM), TaqMan genotyping and Sanger sequencing. RESULTS: NUDT15 mutation R139C (allele *3) was identified in 8 of 423 (1.9%) IBD patients. Seven of eight patients were R139C heterozygous (C/T) and one patient was R139C homozygous (T/T). One of the C/T group and the T/T patient developed thiopurine-induced myelosuppression (TIM) within 60 days of dosing. One patient in the C/T group developed TIM after 60 days of thiopurine dosing. The remaining five patients in the C/T group did not show TIM; however, other thiopurine-related events could not be ruled out and therefore careful monitoring over a long period is recommended. CONCLUSIONS: This is the first study to report the frequency of NUDT15 haplotypes *2,*3,*9 in an Australian IBD population. The most common variant detected was the R139C mutation. PCR and Sanger sequencing are efficient and cost-effective approaches for NUDT15 genotyping.

Differential diagnosis of leukocytosis and leukopenia.

The blood cell count is often examined in routine clinical praxis. Physiologic leucocyte count is in range 4-10 × 109 in liter of blood. Abnormal values of leukocytes and subtypes of leukocytes in differential count are often present. Changes in leukocytes counts are caused by variety of benignant or malignant conditions. It is important in clinical praxis to interpret changes in blood cell count correctly and choose adequate approach in investigation process. In general, leukocytosis and leukocytopenia may present in primary hematologic disorder or secondary/reactive states, caused by reaction of hematopoiesis to underlying condition. This article review common causes of leukocytosis or leucopenia and give basic advice how to investigate patients with changes in leukocytes count.

Effect of the coronavirus pandemic on tumor markers.

The new type of coronavirus could cause severe acute respiratory syndrome and injuries in other systems as well. Multiple organ damage can occur rapidly in patients infected with coronavirus disease 2019 (COVID-19). Previous studies have shown that many laboratory biomarkers were not within the normal ranges in COVID-19 patients. We aimed to summarize laboratory parameters and the tumor markers in COVID-19 patients. This is a retrospective cohort study conducted on 53 women between the ages of 19-85 years infected with COVID-19 at a training and research hospital between May 2020 and August 2020. Of the 53 women, 16 (30.2%) had leukopenia. The mean C-reactive protein level was 18.42 ± 59.33 mg/L. The mean procalcitonin level was 0.1 ± 0.21 µg/L. The liver function tests were within normal limits. The mean creatinine level was 0.58 ± 0.37 mg/dl. Elevated levels of α-fetoprotein (AFP) in 1 patient, elevated levels of carcinoembryonic antigen (CEA) in 2 patients, elevated levels of cancer antigen 125 (CA125) in 4 patients, elevated levels of CA19-9 in 2 patients, and elevated levels of CA15-3 in 2 patients were detected. One of 4 patients who were taken to the intensive care unit had elevated levels of AFP. In addition, 2 of 4 patients who were taken to the intensive care unit had elevated levels of CA125 and CA15-3. Except for AFP, levels of all tumor markers of the patient who died were high. We found that COVID-19 had no effect on tumor markers (CA125, CA19-9, CA15-3, AFP, and CEA).

Disseminated nontuberculous mycobacteriosis and fungemia after second delivery in a patient with MonoMAC syndrome/GATA2 mutation: a case report.

BACKGROUND: Heterozygous mutations in the transcription factor GATA2 result in a wide spectrum of clinical phenotypes, including monocytopenia and Mycobacterium avium complex (MAC) infection (MonoMAC) syndrome. Patients with MonoMAC syndrome typically are infected by disseminated nontuberculous mycobacteria, fungi, and human papillomavirus, exhibit pulmonary alveolar proteinosis during late adolescence or early adulthood, and manifest with decreased content of dendritic cells (DCs), monocytes, and B and natural killer (NK) cells. CASE PRESENTATION: A 39-year-old woman was diagnosed with MonoMAC syndrome postmortem. Although she was followed up based on the symptoms associated with leukocytopenia that was disguised as sarcoidosis with bone marrow involvement, she developed disseminated nontuberculous mycobacterial infection, fungemia, and MonoMAC syndrome after childbirth. Genetic testing revealed a heterozygous missense mutation in GATA2 (c.1114G > A, p.A372T). Immunohistochemistry and flow cytometry showed the disappearance of DCs and decreased frequency of NK cells in the bone marrow, respectively, after childbirth. CONCLUSIONS: To the best of our knowledge, this is the first study reporting that MonoMAC syndrome can be exacerbated after childbirth, and that immunohistochemistry of bone marrow sections to detect decreased DC content is useful to suspect MonoMAC syndrome.

Combining clinical and candidate gene data into a risk score for azathioprine-associated leukopenia in routine clinical practice.

Leukopenia is a serious, frequent side effect associated with azathioprine use. Currently, we use thiopurine methyltransferase (TPMT) testing to predict leukopenia in patients taking azathioprine. We hypothesized that a risk score incorporating additional clinical and genetic variables would improve the prediction of azathioprine-associated leukopenia. In the discovery phase, we developed four risk score models: (1) age, sex, and TPMT metabolizer status; (2) model 1 plus additional clinical variables; (3) sixty candidate single nucleotide polymorphisms; and (4) model 2 plus model 3. The area under the receiver-operating-characteristic curve (AUC) of the risk scores was 0.59 (95% CI: 0.54-0.64), 0.75 (0.71-0.80), 0.66 (0.61-0.71), and 0.78 (0.74-0.82) for models 1, 2, 3, and 4, respectively. During the replication phase, models 2 and 4 (AUC = 0.64, 95% CI: 0.59-0.70 and AUC = 0.63, 95% CI: 0.58-0.69, respectively) were significant in an independent group. Compared with TPMT testing alone, additional genetic and clinical variables improve the prediction of azathioprine-associated leukopenia.

Colchicine and Leukopenia: Clinical Implications.

Colchicine is the mainstay of treatment for familial Mediterranean fever. We investigated the frequency of leukopenia in 213 patients with familial Mediterranean fever treated with standard doses of colchicine (0.5-2.0 mg/day). We found that 23 patients (10.8%) had reversible leukopenia, 3 moderate, and none severe and that their rate of infections was not increased.

The Rate of Infectious Complications After Intrathecal Drug Delivery System Implant for Cancer-Related Pain Is Low Despite Frequent Concurrent Anticancer Treatment or Leukopenia.

BACKGROUND: The efficacy of intrathecal drug delivery (IDD) for cancer-related pain is well established. Cancer therapies are often associated with immunosuppression and increased risk of infection, and the rate of infection after intrathecal drug delivery system (IDDS) implant in cancer patients has been reported as 2.4%-6.3%. Our objective is to report on the rate of surgical site infections (SSI) in patients implanted with IDDS for cancer-related pain and to provide a data-driven discussion on the relationship between antineoplastic treatment, leukopenia, and other clinical or demographic characteristics and SSI. METHODS: Following local institutional review board approval, we conducted a retrospective chart review of IDDS implants from May 2014 through December 2018. Data collected included demographic data, health status, prophylactic antibiotic administration, surgery duration, presence of leukopenia (white blood cell [WBC] count of <4.0 K/µL) or moderate neutropenia (absolute neutrophil count [ANC] of <1000/µL) within the 30 days before IDDS implant, and details of antineoplastic treatment or systemic corticosteroid use in the perioperative period. This information was assessed in relation to SSI incidence up to 6 months following implant. RESULTS: Two hundred seventeen IDDS implants were identified. A majority of patients (79.3%) received ≥1 form of antineoplastic therapy within 30 days before or after implant, and 42.4% received multiple forms of antineoplastic therapy. Therapies included chemotherapy in 46.5%, immunotherapy in 28.6%, systemic steroids in 32.3%, and radiation therapy in 28.1%. One-quarter of patients (25.8%) were leukopenic within 30 days before implant, with 3.2% having moderate neutropenia. There were 2 infectious complications representing an infection rate of 0.9% (95% CI, 0.1%-3.3%), with limited shared characteristics between those experiencing SSI. CONCLUSIONS: SSI risk after IDDS placement for cancer pain is low, despite frequent concurrent antineoplastic therapy and leukopenia in the perioperative period. Concomitant cancer therapies should not be a barrier to the implementation of IDD for cancer pain.

Patient self-testing of white blood cell count and differentiation: A study of feasibility and measurement performance in a population of Danish cancer patients.

OBJECTIVE: Patients in anticancer treatment with a known side effect of neutropenia are monitored closely with laboratory measurements of white blood cell count (WBC) and differentiation. This study sought to evaluate measurement properties and feasibility of patients' self-testing using a point-of-care testing (POCT) device. METHODS: A prospective feasibility and measurement study comparing the standard measurement of cancer patients' WBC and neutrophil count with POCT measurements. The study included 60 outpatients and 22 inpatients from a department of oncology at a university hospital. RESULTS: Patients successfully conducted 106 measurements using the POCT device. 46% of the patients were >70 years. Weighted Deming regression analysis showed minimal yet significant proportional bias between methods, with POCT increasingly underestimating both total WBC and neutrophils compared with the standard method the higher the count. Over 90% of patients reported they were willing and considered themselves able to use the POCT device at home. CONCLUSIONS: The instrument can be used for self-testing of post-anticancer leukopenia and has sufficient measurement precision for patient risk stratification. Patients are able and willing to conduct measurements including when in a situation of acute illness. Further studies are needed to confirm safety and value within patients' own home.

Autoimmune haemolytic anaemia and thrombocytopaenia in a single-centre cohort of patients with systemic lupus erythematosus from Turkey: clinical associations and effect on disease damage and survival.

INTRODUCTION: Thrombocytopaenia and autoimmune haemolytic anaemia (AIHA) have considerable impact on prognosis in systemic lupus erythematosus (SLE). We investigated the frequencies of these haemocytopaenias, along with their associations and effect on outcome in a single-centre cohort of patients with SLE. METHODS: Demographic characteristics, clinical features, autoantibody profiles, damage and mortality data were compared between patients with and without each haematological abnormality. Variables displaying significant differences between the groups were entered into logistic regression. RESULTS: Ninety-three patients had AIHA and 215 had thrombocytopaenia. Both were associated with neuropsychiatric (NP) involvement, with each other, leucopaenia, antiphospholipid syndrome (APS) and antiphospholipid antibodies. More patients in both groups had organ damage, and their damage scores were higher. Association to NP damage was discernible. In addition, cardiovascular and renal damage and diabetes were more pronounced in patients with thrombocytopaenia. At logistic regression analysis, younger age, anticardiolipin antibody IgM positivity, leucopaenia and thrombocytopaenia were associated with AIHA whilst lupus anticoagulant activity, AIHA, leucopaenia, APS and NP involvement were associated with thrombocytopaenia. Among damage items, peripheral vascular damage, diabetes, NP damage, renal and ocular damage displayed significant associations with thrombocytopaenia, whereas none of the items did with AIHA. Patients with AIHA had significantly reduced survival rates at 10 and 20 years. CONCLUSIONS: We observed that AIHA and thrombocytopaenia were associated with severe lupus, affecting major organs and causing end organ damage. Thus, they may be considered as prognostic markers. Furthermore, AIHA and especially thrombocytopaenia may also be a marker for a subgroup of lupus patients who have or may develop APS.

The diagnostic utility of targeted gene panel sequencing in discriminating etiologies of cytopenia.

The diagnostic utility of somatic mutations in the context of cytopenias is unclear: clonal hematopoiesis can be found in healthy individuals, patients with aplastic anemia (AA), clonal cytopenia of undetermined significance (CCUS) and myelodysplastic syndrome (MDS). We examined a cohort of 207 well-characterized cytopenic patients with a 640-gene next generation sequencing (NGS) panel and compared its diagnostic utility with a "virtual" 41 gene panel. The TET2, SF3B1, ASXL1, and TP53 were the most commonly mutated genes (frequency > 10%). Mutations in the 640-gene panel show high sensitivity (98.3%) but low specificity (47.6%) for diagnosis of MDS. Notably, mutations of splicing factors and genes in the RAS pathway are relatively specific to MDS. Furthermore, high variant allele frequency (VAF) predicts MDS: when the VAF is set at 20%, the positive predictive value (PPV) for MDS is 95.9%, with a specificity of 95.3%. The presence of two or more somatic mutations with ≥10% VAF showed a PPV of 95.2%. While the "virtual" 41-gene panel showed a mild decrease in sensitivity (95.7% vs 98.3%), 100% specificity was observed when either VAF was set at ≥20% (100% vs 95.3%), or two or more somatic mutations had VAFs ≥ 10%. Our study shows targeted gene panel sequencing improves the diagnostic approach and accuracy for unexplained cytopenia, with its high sensitivity and high PPV for MDS when applying VAF cutoffs. Furthermore, a 41-gene panel was shown to have at least comparable performance characteristics to the large 640-gene panel.

Long-term effect of NUDT15 R139C on hematologic indices in inflammatory bowel disease patients treated with thiopurine.

BACKGROUND AND AIM: A missense variant of the nucleoside diphosphate-linked moiety X-type motif 15 (NUDT15) gene (R139C) predisposes Asian patients with inflammatory bowel disease (IBD) to thiopurine-induced leukopenia. This study evaluates the long-term effect of NUDT15 R139C heterozygosity on hematological parameters during thiopurine administration. METHODS: We enrolled 83 Japanese IBD patients who were on anti-tumor necrosis factor-α agents and had used thiopurine. NUDT15 R139C was genotyped by polymerase chain reaction. We retrospectively reviewed patient clinical charts to collect data on white blood cell (WBC) count, mean corpuscular volume (MCV), hemoglobin, and platelet count during the 24 months following thiopurine initiation. RESULTS: The included patients had either Crohn's disease (54; 65.1%) or ulcerative colitis (29; 34.9%). Genotyping of NUDT15 R139C identified 62 patients (74.7%) of genotype C/C and 21 (25.3%) of genotype C/T. The median dose of thiopurine was lower in the C/T group than in the C/C group after starting thiopurine. At 6 months, the mean WBC count of the C/T group became significantly lower than that of the C/C group (P = 0.008) and remained lower through the 24 months. The C/T group developed grade 2-4 leukopenia by 6 months, which persisted through 12-24 months. The mean MCV in the C/T group became higher than that of the C/C group after 3 months. CONCLUSIONS: NUDT15 R139C heterozygosity affected the WBC count and MCV for 24 months after thiopurine administration. Our results indicate that careful monitoring of leukopenia and dose adjustment are necessary throughout treatment in IBD patients heterozygous for the NUDT15 R139C.

Recent advances in understanding the pathogenesis and management of reticular dysgenesis.

Reticular Dysgenesis is a rare immunodeficiency which is clinically characterized by the combination of Severe Combined Immunodeficiency (SCID) with agranulocytosis and sensorineural deafness. Mutations in the gene encoding adenylate kinase 2 (AK2) were identified to cause this phenotype. In this review, we will demonstrate important clinical differences between reticular dysgenesis and other SCID entities and summarize recent concepts in the understanding of the pathophysiology of the disease and the management strategies for this difficult condition.

Diagnostic accuracy of NUDT15 gene variants for thiopurine-induced leukopenia: a systematic review and meta-analysis.

We herein conducted a systematic review and meta-analysis of published studies to estimate diagnostic accuracy of NUDT15 gene polymorphisms for detection of thiopurine-induced leukopenia. Eligible studies were identified through a comprehensive search on PubMed, Web of Knowledge, Cochrane and OpenGrey datasets up to April 2018. The methodological quality of eligible studies was assessed using the QUADAS-2 criteria. The diagnostic odds ratio (DOR) was used as a single measure of diagnostic performance. Sixteen studies including a total of 3538 thiopurine-treated patients fulfilled inclusion criteria for the systematic review. Among these, 16 studies were available for the meta-analysis of rs116855232, 6 studies for rs186364861 and 5 studies for rs554405994 of NUDT15. A higher DOR was found for rs116855232 (8.44, 95% CI: 5.46-13.03), as compared to rs554405994 (4.336, 95% CI 2.924-6.429) or rs186364861 (2.742, 95% CI 1.453-5.175). Results of meta-regression analysis showed that incidence of leukopenia (relative DOR: 0.96; 95%CI: 0.93-1.00, p = 0.037) and leukopenia onset (late vs early leukopenia, relative DOR: 0.41, 95% CI 0.20-0.85, p = 0.0189) significantly influenced diagnostic accuracy of rs116855232. Subgroup analysis for rs186364861 and rs554405994 revealed a significant DOR for early-onset leukopenia (rs186364861: 4.04, 95% CI 1.78-9.20; rs554405994: 2.94, 95% CI 1.74-4.95), but not for late-onset leukopenia (rs186364861: 1.52, 95% CI 0.52-4.43; rs554405994: 2.02, 95% CI 0.93-4.40). The present meta-analysis points to rs116855232, rs554405994 and rs186364861 of NUDT15 as clinically relevant predictors of thiopurine-induced leukopenia. Nevertheless, prospective studies of genotype-guided dosing of thiopurines are warranted to prove clinical benefit and cost-effectiveness of pretreatment NUDT15 gene testing across different populations.

Efficacy and tolerance of GELOXD/P-GEMOXD in newly diagnosed nasal-type extranodal NK/T-cell lymphoma: A multicenter retrospective study.

OBJECTIVES: Nasal-type extranodal natural killer NK/T-cell lymphoma (ENKTCL) is a distinct type of non-Hodgkin lymphoma with poor prognosis. This research aimed to evaluate the efficacy and safety of the GELOXD or P-GEMOXD regimens in patients with ENKTCL. METHODS: Newly diagnosed ENKTCL patients treated with either the GELOXD or the P-GEMOXD regimen were identified from three cancer centers between January 2010 and December 2016. Kaplan-Meier and Cox regression analyses were used to calculate overall survival (OS) and progression-free survival (PFS) and to investigate prognostic factors. RESULTS: One hundred and eighty-four cases were identified from three cancer centers. After 1-5 treatment cycles of GELOXD or P-GEMOXD chemotherapy, 155 (84%) patients showed a complete response (CR). The 3-year OS (73.0% vs 38.2%, P = .001) and PFS (72.8% vs 32.4%, P = .000) rates were significantly higher in early-stage patients compared with advanced-stage patients. A multivariate analysis revealed that patient CR status was a significant independent factor in disease prognosis. Grade 3/4 leukopenia occurred in 43 (23.4%) patients. Major non-hematological toxicities included nausea (n = 117, 63.6%) and vomiting (n = 66, 35.9%). CONCLUSIONS: The GELOXD and P-GEMOXD chemotherapy regimens are well tolerated and provide favorable survival outcomes in patients with ENKTCL.

Cortisol is More Important than Metanephrines in Driving Changes in Leukocyte Counts after Stroke.

BACKGROUND: There are notable changes in the number of white blood cells (WBCs) after stroke, but the primary mediators of these changes are unclear. In this study, we assessed the role of the neuroendocrine and sympathetic nervous systems in stroke-induced changes of WBCs within distinct leukocyte subsets, as well as the effect of these changes on stroke outcomes. METHODS: Patients were recruited within 72 hours after ischemic stroke; complete blood count with differential was obtained at set time points. The relationships among leukocyte numbers, cortisol, adrenocorticotropic hormone, interleukin-6, and metanephrines were assessed at 72 hours after stroke. Associations between abnormal leukocyte counts at 72 hours, poststroke infection, and 3-month outcomes were determined. RESULTS: A total of 114 subjects were enrolled. Severe stroke was associated with leukocytosis, neutrophilia, monocytosis, lymphopenia, and eosinopenia. At 72 hours after stroke, increased serum cortisol was independently associated with neutrophilia and lymphopenia. Abnormal leukocyte counts were not independently predictive of poststroke infection, but lymphopenia was associated with poor outcome (modified Rankin score >3) at 3 months after stroke (odds ratio = 22.86 [1.95, 267.65]; P = .01). CONCLUSIONS: Increased serum cortisol is independently associated with neutrophilia and lymphopenia after stroke. Lymphopenia is not an independent predictor of infections but is independently associated with worse outcome.