Use of oral mucosal neutrophil counts to detect the onset and resolution of profound neutropenia following high-dose myelosuppressive chemotherapy

Association of neutrophil defects with oral ulcers but undetermined role of neutrophils in recurrent aphthous stomatitis

Objective

Recurrent oral ulcers and severe periodontal diseases in patients with quantitative or qualitative neutrophil defects highlight the important role of neutrophils in maintaining oral mucosal barrier homeostasis. Recurrent aphthous stomatitis (RAS) is a common oral mucosal disease affecting up to 25% of the population, yet its etiopathogenesis remains unclear, and management is unsatisfactory. This review aims to gain insight into the pathogenesis of RAS.

Design

This narrative review examines the characteristics of oral and blood neutrophils, the associations between neutrophil defects and the occurrence of oral ulcers, and the evidence for the involvement of neutrophils in RAS. To conduct the review, relevant literature was searched in PubMed and Google Scholar, which was then thoroughly reviewed and critically appraised.

Results

Neutropenia, specifically a decrease in the number of oral neutrophils, impaired extravasation, and defective ROS production appear to be associated with oral ulcers, while defects in granule enzymes or NETosis are unlikely to have a link to oral ulcers. The review of the histopathology of RAS shows that neutrophils are concentrated in the denuded area but are latecomers to the scene and early leavers. However, the evidence for the involvement of neutrophils in the pathogenesis of RAS is inconsistent, leading to the proposal of two different scenarios involving either impaired or hyperactive neutrophils in the pathogenesis of RAS.

Oral mucositis: Current knowledge and future directions

Oral mucositis secondary to head and neck chemoradiation displays a complex molecular pathogenesis involving epithelial and microvascular injury, release of pro-inflammatory cytokines, and host-microbiome communications. These processes lead to oxidative stress and the release of reactive oxygen species that stifle the structural integrity of the oral mucosa, with emergence of erosions and ulcers. The consequences are malnutrition, psychological/psychiatric symptoms, poor quality of life, and occurrence of opportunistic infections. The latter pose a major challenge due to the risk of interruption of anti-neoplastic therapy, tumour recurrence and, ultimately, death. This article aims to present the clinical characteristics, molecular pathogenesis, and an overview of the predisposing factors and current management of oral mucositis. It is anticipated that the future direction of the management of oral mucositis will focus on evidence-based prehabilitation and pre- and per-chemoradiation therapy monitoring.

Reductions in clinical inflammation and oral neutrophils with improving oral hygiene

OBJECTIVE

This study compared the effects of oral hygiene with a toothpaste formulated with zinc (test) to a fluoride dentifrice (control) for effects on oral polymorphonuclear leukocyte (PMN) as a measure of whole mouth inflammation along with effects on clinical parameters of dental plaque and gingivitis.

MATERIALS AND METHODS

Adults (age range 18-60 years, n = 212) completed this double-blind, parallel design study. After washout, a baseline oral rinse sample was evaluated for PMN prior to clinical assessments for gingivitis and dental plaque. Subjects were randomly assigned to brush twice daily with either the test or the control toothpaste. Post-treatment evaluations repeated all baseline assessments after 4-week, 6-week and 12-week use of dentifrice with all assessments conducted 12 hours after brushing.

RESULTS

PMN reductions in the test were 16.8%, 18.7% and 42.5% at the 4-week, 6-week and 12-week evaluations respectively and significantly different from the control (p < 0.05). The test toothpaste also demonstrated progressively increasing reductions in gingivitis and dental plaque that ranged from 7.6 to 33.3% and 2.3 to 9.1% respectively versus the control (p < 0.05).

CONCLUSIONS

The test dentifrice demonstrated progressive reductions in oral PMN representing whole mouth inflammation in conjunction with improvements in oral hygiene as compared to the control toothpaste.

CLINICAL RELEVANCE

A hallmark of oral inflammation includes the accumulations of PMN in the afflicted gingival regions to reduce the influences of proliferating microorganisms. Brushing with a zinc dentifrice demonstrated progressive reductions in oral PMN and improvements in oral hygiene as evidenced by progressively lower dental plaque and gingival indices.

Oral Neutrophils: Underestimated Players in Oral Cancer

The composition of the oral milieu reflects oral health. Saliva provides an environment for multiple microorganisms, and contains soluble factors and immune cells. Neutrophils, which rapidly react on the changes in the microenvironment, are a major immune cell population in saliva and thus may serve as a biomarker for oral pathologies. This review focuses on salivary neutrophils in the oral cavity, their phenotype changes in physiological and pathological conditions, as well as on factors regulating oral neutrophil amount, activation and functionality, with special emphasis on oral cancer and its risk factors.

Female sex as an independent prognostic factor in the development of oral mucositis during autologous peripheral stem cell transplantation

Oral mucositis (OM) is a frequent complication of stem cell transplantation-associated toxicity in haematological malignancies, contributing to mortality. Therapy still remains mainly supportive. We assessed risk factors in retrospective analysis of 192 autologous peripheral stem cell transplantation patients with lymphoma and multiple myeloma (MM), respectively. Futhermore, we examined the hormone levels both in serum and saliva during transplantation in 7 postmenopausal female patients with lymphoma compared to healthy controls using electrochemiluminescence immunoassay (ECLIA). Multivariable analysis revealed neutrophil engraftment (p < 0.001; p = 0.021) and female sex (p = 0.023; p = 0.038) as independent predictive factors in the combined patient group and in the lymphoma group, and neutrophil engraftment (p = 0.008) in the MM group. Of the 85 female participants 19 were pre- and 66 postmenopausal. Fifteen of the pre-, and 49 of the postmenopausal women developed ulcerative mucositis (p = 0.769), more often with lymphoma than MM (p = 0.009). Serum estrogen decreased significantly both in postmenopausal controls and transplantated patients compared to premenopausals, with no difference in saliva. Serum progesterone level was significantly (p = 0.026) elevated at day + 7 of transplantation, while salivary progesterone increased at day + 7 and + 14. Our results indicate a predominantly negative effect of female sex hormones on oral immunity with role in the aetiopathogenesis of OM.

IL-6 -572C>G and CARD8 304T>A Genetic Polymorphisms are Associated with the Absolute Neutrophil Count in Patients with Hematological Malignancies Under Chemotherapy: An Application of Multilevel Models to a Preliminary Pharmacogenetic Study

Purpose

Neutropenia is a common event in patients undergoing cytotoxic chemotherapy for the treatment of a hematological malignancy. Some polymorphisms, as IL-6 -572C>G (rs1800796), IL-1β -31 G>A (rs1143627), and CARD8 304T>A (rs2043211), in genes related to the inflammatory process, could affect the level of absolute neutrophil count (ANC) after chemotherapy. Since an efficient inflammatory process enhances neutrophil survival, we hypothesize that these polymorphisms are associated with ANC.

Patients and Methods

We carried out a prospective cohort study in two hospitals in Santiago, Chile. The patients included were adults diagnosed with acute myeloblastic leukemia, acute lymphoblastic leukemia, or non-Hodgkin's lymphoma, undergoing cytotoxic chemotherapy. We use a multilevel linear regression model to test our hypothesis. The best model was selected using the Akaike's information criterion (AIC).

Results

We analyzed 1726 hemograms and ANCs from 172 hospitalizations from 32 patients. The results show that CC and CG genotypes of IL-6 -572 C>G polymorphism are associated with higher ANCs compared with the GG genotype (Ln (ANC) ~ 0.81 IC95% 0.02-1.55). Similarly, TT and AT genotypes of CARD8 304T>A polymorphism were related to higher ANCs compared with AA (Ln (ANC) ~ 0.95 IC95% 0.02-1.82). IL-1β genetic polymorphism had no statistically significant association with ANC.

Conclusion

IL-6 rs1800796 -572C>G and CARD8 rs2043211 304T>A polymorphisms are associated with the absolute neutrophil count in patients undergoing cytotoxic chemotherapy for treatment of hematological malignancies. Our findings might be useful to improve the safety of chemotherapy through predictive ANC models.

Effects of a chlorhexidine mouthwash on clinical parameters of gingivitis, dental plaque and oral polymorphonuclear leukocytes [PMN]

Histological features of oral inflammation include infiltration of polymorphonuclear leukocytes [PMN], however studies have not examined the effects of interventions mitigating inflammation on oral PMN. Methods: This double-blind clinical study examined the effects of rinsing with mouthwashes formulated with chlorhexidine [CHX], an ingredient widely utilized in the dental clinic in comparison to a control on oral PMN representing a novel measure of inflammation. A concurrent evaluation of dental plaque and gingival inflammation using widely accepted clinical indices was included in the study. The study enrolled adult subjects providing informed consent, met study criteria and registered gingival index scores of 1.0 or more at the screening visit. Subjects [n = 90; age range 19–58 years] completed a washout phase prior to baseline evaluations for PMN and clinical assessments for dental plaque and gingivitis. Treatments [CHX or a control mouthwash] were randomly assigned to subjects for twice-daily use for the next two weeks. Post-treatment evaluations similar to baseline were conducted after one and two week use of assigned treatment. Results: At baseline, no statistically significant differences between treatment groups for PMN or clinical indices for dental plaque or gingivitis were noted. Rinsing with CHX demonstrated significant reductions for PMN and dental plaque, gingivitis in comparison to the control group. After one and two week use of CHX, PMN demonstrated a 35.9% and 54.9% reduction respectively in comparison to the control group representing significant differences [p < 0.05]. At the one and two week post-treatment evaluations, rinsing with CHX demonstrated 15% and 25% reductions in gingivitis respectively and were significantly different from the control [p < 0.05]. Rinsing with CHX also demonstrated significant reductions in dental plaque of 15% and 19% at the one and two-week post-treatment evaluations respectively in comparison to the control [p < 0.05]. The CHX group also demonstrated reductions in interproximal scores and registered the lowest frequency of gingival index or dental plaque scores on all oral surfaces. Conclusions: Results outline an objective approach to evaluate oral inflammation demonstrating a large and sustained reduction in oral PMN by CHX with these outcomes numerically higher than a clinical index evaluating gingivitis.

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Enumeration of oral polymorphonuclear leukocytes [PMN] estimates the oral inflammatory burden.

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Rinsing with chlorhexidine demonstrated progressive PMN reductions corroborating gingivitis and dental plaque evaluations.

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Rapid PMN assessment provides objective assessment of treatment effects applicable for dental chair-side setting.

Oral neutrophils are an independent marker of the systemic inflammatory response after cardiac bypass

Background

Cardiopulmonary bypass (CPB) is an immuno-reactive state where neutrophils are activated and accumulate in different tissues. Edema and tissue necrosis are the most common sequelae observed, predominantly in the lungs, kidneys, and heart, heralding significant risk for postoperative complications. No method exists to noninvasively assess in vivo neutrophil activity. The objective of this study was to determine if neutrophil recruitment to the oral cavity would correlate with specific biomarkers after coronary bypass surgery (CPB).

Methods

We conducted a single site prospective observational study including non-consecutive adult patients undergoing elective, on-pump CPB. Blood and either oral cavity rinses or swabs were collected pre- and post-CPB. Absolute neutrophil counts from oral samples and serum biomarkers were measured. The association between neutrophil recruitment to the oral cavity, biomarkers and outcomes after CPB were analyzed.

Results

CPB was associated with statistically significant increases in oral and blood neutrophil counts, as well as an increase in certain biomarkers over preoperative baseline. Peripheral blood neutrophil count were increased at all time points however statistically significant differences in median oral neutrophil counts were observed only at the time point immediately postoperative, and in what seems to be two unique patient populations (p < 0.001; group 1, median: 1.6×10⁵, Interquartile range [IQR], 1.1×10⁵ - 4.8×10⁵, and group 2, median: 1.9×10⁶, IQR, 8.7×10⁵ - 4.0×10⁶).

Conclusions

CPB is associated with a transient increase in oral neutrophils that may correlate with the systemic inflammatory response; oral neutrophils may have the ability to discriminate and identify unique patient populations based on their tissue migration.

Incidence and management of infections in patients with acute leukemia following chemotherapy in general wards

We hypothesise that treating patients with acute leukaemia in general wards, with proper hygienic and sanitary practices, would result in the minimum utilisation of resources as compared with the corresponding patients receiving ICU support. For this study, the acute leukaemia patients on induction chemotherapy were kept in general wards and observed for the incidence of neutropenia, resultant neutropenic febriles, the causative organism, and the effect of empirical antimicrobial treatment protocol on the outcome of such infections. Prophylactic anti-fungal therapy and cotrimoxazole therapy improved the outcome of infections. The therapy of neutropenic fever and infections must be adapted according to the risk factors and should include early empiric antifungal therapy. It was observed that the treatment of such patients in general wards could be managed effectively, with the added advantage of optimum utilisation of resources and in a patient-friendly environment, at a reasonable cost to the patients.

Salivary neutrophils level as an indicator of bone marrow engraftment

AIM

The aim of this study was to investigate the neutrophils level in saliva as an adequate alternative to other methods for evaluating the neutrophil engraftment after autologous stem cell transplantation (ASCT) in hemato-oncology.

METHOD

A total of 35 patients treated for non-Hodgkin's lymphoma or multiple myeloma were stomatologically examined before planned high-dose chemotherapy with ASCT. After removal of potential foci of odontogenic infection all the patients underwent transplantation and during the treatment they were monitored for the level of neutrophils in saliva as a possible early indicator of the neutrophil engraftment. Neutrophil levels in saliva were compared to the neutrophil level in blood and to the degree of oral mucositis (the nurses study).

RESULTS

An increase of salivary neutrophils in the mouth rinse of > 25 x 10/\6/l was identified as an early sign of successful neutrophil engraftment that occurred 1 to 2 days before the rise of neutrophils in peripheral blood (> 0.5- x 10/\9/l).

CONCLUSIONS

Follow-up of neutrophil levels in saliva might be an adequate alternative to other methods for evaluating the neutrophil engraftment after ASCT in hemato-oncology.

Granulocyte transfusions in children and young adults: does the dose matter?

BACKGROUND

Granulocyte transfusions (GTs) may increase the absolute neutrophil count (ANC) before hematopoietic regeneration in neutropenic patients after chemotherapy or hematopoietic stem cell transplantation and support anti-infective immunity.

PROCEDURE

We assessed efficacy and tolerability of 778 GTs in 70 treatment episodes of 49 children and 10 young adults [median age 6.28 y (range: 0.13 to 17.7 y) and 21 y (18.0 to 28.0), respectively] suffering from bacterial (n=55) and/or fungal (n=31) infections during neutropenia owing to conventional chemotherapy (n=14), hematopoietic stem cell transplantation conditioning (n=44), or the underlying disease (n=1). We analyzed the impact of body weight, organ dysfunction, neutrophil dose on ANC increment, infection elimination, and survival.

RESULTS

The median day-5 ANC increment was 1460/microL, correlating to the administered dose. However, 28-day survival did not correlate to the neutrophil dose nor to the ANC increment, potentially owing to the high number of neutrophils transfused to all patients (median >6x10(9)/kg within 5 d). The 28-day survival probability of the total patient cohort was 0.72+/-0.06 and the 100-day survival was 0.52+/-0.07. Adverse reactions were rare including fever (< or =World Health Organization grade III, 14%), chills (3%), and mild pulmonary complications (1%).

CONCLUSIONS

These data corroborate the empirical evidence that GT with sufficient cell doses and rapid availability are a feasible, well-tolerated supplemental means to fight severe infections in neutropenic patients.

Reticulocyte Maturation Parameters Are Reliable Early Predictors of Hematopoietic Engraftment after Allogeneic Stem Cell Transplantation

Early detection of donor-derived hematopoietic restoration after allogeneic stem cell transplantation (allo-SCT) is a crucial issue in the management of heavily immunocompromised patients. The aim of this prospective study was to validate our previously defined cutoff values for reticulocyte maturation parameters as early predictors of hematopoietic engraftment. Importantly, the effect of clinical variables in reticulocyte engraftment was also sought. For this purpose, we prospectively studied 136 consecutive patients undergoing allo-SCT from related (n = 89) or unrelated (n = 47) donors. High fluorescence reticulocytes (RETH), immature reticulocyte fraction (IRF), mean fluorescence index (MFI), and mean reticulocyte volume (MRV) were automatically measured in peripheral blood samples drawn on a daily basis. We previously defined reticulocyte engraftment when MFI > or =10, RETH > or =3%, IRF > or =10%, and MRV > or =110 fL. Median neutrophil engraftment was 18 days (range, 10-35 days); for reticulocyte parameters, the values were 14 days for IRF (range, 7-45 days), 14 days for MFI (range, 7-43 days), 15 days for RETH (range, 7-43 days), and 21 days for MRV (range, 9-74 days). These differences reached statistical significance for MFI and IRF when compared with standard neutrophil recovery, even when analyzing siblings or unrelated donors separately. In univariate analysis, donor-recipient ABO disparity adversely influenced erythroid engraftment (P = .04 for IRF, P = .03 for MFI), but the infusion of >2.9 x 10(6)/kg of CD34+ cells was associated with a shorter time to reach erythroid engraftment (P = .02 for IRF and MFI). In Cox regression analysis, > or =100/microL neutrophils and IRF > or =10% were predictive parameters for standard neutrophil engraftment. Based on these findings, we suggest that serial measurement of IRF or MFI should be routinely used to trace hematopoietic restoration after allo-SCT because these preceded standard neutrophil recovery by a median of 4 days and are therefore very useful to make clinical decisions.

Recovery from neutropenia can be predicted by the immature reticulocyte fraction several days before neutrophil recovery in autologous stem cell transplant recipients

The duration of neutropenia (absolute neutrophil count (ANC) < or = 100/microl) identifies cancer patients at risk for infection. A test that precedes ANC > or = 100/microl would be of clinical value. The immature reticulocyte fraction (IRF) reflects erythroid engraftment and hence a recovering marrow. We evaluated the IRF as predictor of marrow recovery among 90 myeloma patients undergoing their first and second (75 patients) melphalan-based autologous stem cell transplantation (Mel-ASCT). The time to IRF doubling (IRF-D) preceded ANC > or = 100/microl in 99% of patients after the first Mel-ASCT by (mean+/-s.d.) 4.23+/-1.96 days and in 97% of the patients after the second Mel-ASCT by 4.11+/-1.95 days. We validated these findings in a group of 117 myeloma patients and 99 patients with various disorders undergoing ASCT with different conditioning regimens. We also compared the time to hypophosphatemia and to absolute monocyte count > or = 100/microl to the time to ANC > or = 100/microl. These markers were reached prior to this ANC end point in 55 and 25% of patients but were almost always preceded by IRF-D. We conclude that the IRF-D is a simple, inexpensive and widely available test that can predict marrow recovery several days before ANC> or = 100/microl.

A noninvasive oral rinse assay to monitor engraftment, neutrophil tissue delivery and susceptibility to infection following HSCT in pediatric patients

The time interval between neutrophil tissue delivery and blood confirmed engraftment following hematopoietic stem cell transplantation (HSCT) may serve as an indicator of patient susceptibility to infection. Using an oral rinse protocol, we studied neutrophil tissue delivery kinetics and its relationship to clinical parameters post-HSCT in 29 pediatric patients. Oral neutrophil counts were compared to circulating neutrophil levels, oral mucositis scores and infection-related febrile episodes after engraftment. Blood engraftment (BE) is currently defined by a blood neutrophil count of > or =0.5 x 10(9)/l. We defined oral engraftment (OE) as the day neutrophils returned in the mouth post-HSCT (> or =0.25 x 10(4)/ml oral neutrophils in the rinse sample). We found that neutrophils reappeared 6.3+/-3.9 s.d. days earlier in the mouth than in the circulation enabling us to identify successful engraftment almost 1 week sooner than using blood count values alone. Furthermore, the time-span between OE and BE was inversely related to the number of infection-related febrile episodes post-BE. We conclude that monitoring the timing of neutrophil tissue delivery through a rapid oral rinse may yield important insights into the biology of neutrophil recovery during and after engraftment and the factors associated with neutrophil tissue recruitment.