Raised salivary endotoxin concentration as a predictor of infection in pediatric leukemia patients

Bacterial endotoxins and microorganisms in the oral cavities of patients on cancer therapy

OBJECTIVES

This study investigated the presence of Streptococci, Staphylococci, aerobic gram negative bacteria (AGNB), Candida and bacterial endotoxins in the oral cavities of patients receiving chemo- and/or radiotherapy for cancer.

METHODS

Samples of oral cavity rinse were collected from 100 patients on cancer treatment and 70 healthy individuals. Demographic and clinical data were recorded. Samples were cultured onto various agar plates for qualitative and quantitative analysis and tested for the presence of endotoxin. Results were analysed using the Mann-Whitney and chi-square tests.

RESULTS

In cancer patients, S. aureus counts were high and 66.7% of patients on chemo- and radiotherapy carried these bacteria (p=<0.05). The Candida carrier rate was significantly (p < 0.01) high in cancer patients (54%). No significant difference was found in the carrier rate of Streptococci and AGNB between the healthy and cancer group as well as between the cancer patients with chemo and radio- and chemotherapy alone. No significant difference was found in the level of endotoxin between the cancer patients and healthy individuals, and cancer patients with and without AGNB.

CONCLUSIONS

No differences in the prevalence of bacteria and bacterial endotoxins were found between the cancer patients and healthy individuals. Oral cavity endotoxins did not correlate with the carriage of AGNB. However, due to the high prevalence in cancer patients, the role of Candida species and S. aureus in the pathology may not be excluded.

Saliva initiates the formation of pro-inflammatory macrophages in vitro

OBJECTIVES

Saliva can support oral wound healing, a process that requires a temporary inflammatory reaction. We have reported previously that saliva provokes a strong inflammatory response in oral fibroblasts. Bone marrow cells also give rise to macrophages, a heterogeneous subset of cell population involved in wound healing. Lipopolysaccharide (LPS) and interleukin 4 (IL-4) induce activation of pro-(M1), and anti-(M2) inflammatory macrophages, respectively. Yet, the impact of saliva on programming bone marrow cells into either M1 or M2 macrophages remains unclear .

DESIGN

Herein, we examined whether sterile saliva affects the in vitro process of macrophage polarization based on murine bone marrow cultures and RAW264.7 mouse macrophages.

RESULTS

We report that sterile saliva, similar to lipopolysaccharides, provoked a robust activation of the M1 phenotype which is characterized by a strong increase of the respective genes IL-12 and IL-6, based on a real-time gene expression analysis, and for IL-6 with immunoassay. Arginase-1 and Ym1, both genes characteristic for the M2 phenotype, were not considerably modulated by saliva. Inhibition of TLR4 signaling with TAK-242, blocking NFκB signaling with Bay 11-7085, but also autoclaving saliva greatly reduced the development of the M1 phenotype.

CONCLUSION

These data suggest that saliva activates the TLR4 dependent polarization into pro-inflammatory M1 macrophages in vitro.

Frequency of oral mucositis and microbiological analysis in children with acute lymphoblastic leukemia treated with 0.12% chlorhexidine gluconate

In view of the morbidity potential of oral complications in patients with leukemia, this study evaluated the clinical and microbiological alterations that occur in the oral mucosa of children with acute lymphoblastic leukemia (ALL) undergoing antineoplastic chemotherapy and prophylactic administration of 0.12% chlorhexidine gluconate. The sample consisted of 17 children aged 2 to 12 years that underwent clinical examination of the oral mucosa for the detection of oral lesions. In addition, biological material was collected from labial and buccal mucosa for microbiological analysis. Oral mucositis was observed in only 5 (29.4%) patients. Microbiological analysis revealed a reduced number of potentially pathogenic microorganisms, such as coagulase-negative staphylococci (47%), Candida albicans (35.3%), Klebsiella pneumoniae (5.9%), enteropathogenic Escherichia coli (5.9%), and Stenotrophomonas maltophilia (5.9%). Patients with oral mucositis showed a higher frequency of coagulase-negative staphylococci (80%) when compared with patients with normal oral mucosa (33.3%). In conclusion, the results of the present study suggest that the prophylactic use of 0.12% chlorhexidine gluconate reduces the frequency of oral mucositis and oral pathogens in children with ALL. In addition, the present findings suggest a possible relationship between coagulase-negative staphylococci and the development of oral mucositis.

Oral health status in children with acute lymphoblastic leukemia

Leukemia is a malignancy of the bone marrow. Acute lymphoblastic leukemia (ALL) is the most common pediatric malignancy and accounts for nearly 75% of all newly diagnosed leukemias and 25% of all malignancies in childhood. The aim of the present study was to review the oral health status in children with ALL. Databases were explored using various combinations of the following keywords: "acute lymphoblastic leukemia", "children", "inflammation", "pediatric", "periodontal disease" and "periodontitis". Oral inflammatory conditions including chelitis, gingivitis, herpetic gingivostomatitis, mucositis, oral candidiasis, periodontitis and ulcerations are common manifestations in children with ALL.

RESULTS

Periodontal inflammatory conditions and oral mucositis were reported to be significantly higher in children with ALL as compared to healthy controls. Tooth morphological disorders including agenesis, microdontia, short roots and developmental defects in the enamel and dentin were more often observed in children with ALL as compared to healthy controls. Children with ALL have a reduced salivary flow rate, which makes them more susceptible to dental caries as compared to healthy children. Malocclusion due to microdontia may also trigger temporomandibular joint disorders in children with ALL; however, this relationship needs further investigations.

CONCLUSION

Oral inflammatory conditions including mucositis and gingivitis are common in children with ALL as compared to healthy children. Tooth morphological disorders including microdontia and enamel and dentin are common manifestations in children with ALL.

Total viable counts, ATP, and endotoxin levels as potential markers of microbial contamination of dental unit water systems

OBJECTIVES

To determine if either ATP or endotoxin concentrations in water supplied by dental unit water systems (DUWS) correlated with total viable counts (TVC), and therefore could be used as a rapid, chairside measure of levels of microbial contamination.

DESIGN

A prospective trial.

METHOD

Fifty-seven water samples were taken from the 'triple spray', air rotor and source water supplies from 25 dental units in eight practices. The samples were assayed for endotoxin concentration, total ATP and TVC. A pilot study was performed to assess the relationship between TVC and total cell counts, as determined by flow cytometry.

RESULTS

ATP concentrations ranged from 22 to 958 relative light units (RLU) and free endotoxin ranged from 25 to 600 EU ml(-1). TVC varied from not detected to 2.16 x 10(4) CFU ml(-1). The ATP method proved to be a simple and rapid method that could be used at the chairside. However, there was no correlation between ATP or endotoxin concentrations and TVC in DUWS. TVC generally underestimated the total cell count by 50 to 500 fold.

CONCLUSION

Half of the water samples from DUWS exceeded recommended levels of TVC. However, ATP and endotoxin concentrations in DUWS water samples did not correlate with these TVC data and therefore could not be recommended as an alternative assay to TVC for measuring bacterial contamination or for monitoring water treatment efficacy.

Saliva as a diagnostic fluid

In the last 10 years, the use of saliva as a diagnostic fluid has become somewhat of a translational research success story. Technologies are now available enabling saliva to be used to diagnose disease and predict disease progression. This review describes some important recent advances in salivary diagnostics and barriers to application and advancement. This review will also stimulate future research activity.

A preliminary investigation of the microbiology and endotoxin content in the water reservoirs of benchtop non-vacuum autoclaves

To determine the microbial content and endotoxin concentration in the water reservoirs of benchtop autoclaves used in general dental practice.

DESIGN

The study was done in two stages. Firstly water samples were taken daily from the reservoirs of 20 autoclaves used in general dental practices for six days. The microbial content and endotoxin concentration was determined. Second the practitioners were instructed to wash and clean the reservoirs of the autoclaves each morning prior to refilling with fresh water. The reservoirs were sampled in the evenings after a day's use and the microbial content and endotoxin concentration determined.

RESULTS

The total viable count of bacteria before cleaning varied from 2,300 - 8 x 10(4) cfu/ml and after from 0-40 cfu/ml. The endotoxin concentrations before cleaning varied from 360-2,200 EU/ml and after 0-80 EU/ml.

CONCLUSIONS

The reservoirs of non-vacuum benchtop autoclaves can become severely contaminated with micro-organisms particularly Gram-negative bacteria. The endotoxin content of the reservoirs can get to high and unacceptable concentrations. Draining the water reservoir and cleaning on a daily basis reduces the microbial content and the endotoxin concentration to acceptable levels.