Quantitative distribution of inflammatory cells in recurrent aphthous stomatitis

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.

Diagnostic Significance of Neutrophil to Lymphocyte Ratio in Recurrent Aphthous Stomatitis: A Systematic Review and Meta-Analysis

INTRODUCTION

Recurrent aphthous stomatitis (RAS) is a prevalent ulcerative condition affecting oral mucosa.

OBJECTIVES

A systematic review and meta-analysis was performed to compare the level of neutrophil to lymphocyte ratio (NLR) between individuals with RAS and those who are healthy.

METHODS

A systematic search for relevant publications before June 21, 2022, was conducted using Web of Science, PubMed, and Scopus. The results were presented as the standardized mean difference (SMD) with a 95% confidence interval (CI), and a random-effects model was used to calculate pooled effects due to the presence of significant heterogeneity. Quality assessment was performed using the Newcastle-Ottawa scale.

RESULTS

Overall, 13 article with were included in the analysis. NLR was higher among patients with RAS compared to healthy controls (SMD = 0.50, 95% CI = -0.20 to 0.79, P = 0.001, I2 = 91.5%). In the subgroup analysis based on the study design, it was found that retrospective studies showed higher levels of NLR in patients with RAS compared to healthy controls (SMD = 0.62, 95% CI= 0.16 to 1.08, P < 0.01), but these results were not applied to prospective studies (SMD = 0.35, 95% CI = -0.03 to 0.74, P < 0.07).

CONCLUSION

Elevated neutrophil to lymphocyte ratio revealed crosstalk between systematic inflammation and RAS.

Genome wide analysis for mouth ulcers identifies associations at immune regulatory loci

Mouth ulcers are the most common ulcerative condition and encompass several clinical diagnoses, including recurrent aphthous stomatitis (RAS). Despite previous evidence for heritability, it is not clear which specific genetic loci are implicated in RAS. In this genome-wide association study (n = 461,106) heritability is estimated at 8.2% (95% CI: 6.4%, 9.9%). This study finds 97 variants which alter the odds of developing non-specific mouth ulcers and replicate these in an independent cohort (n = 355,744) (lead variant after meta-analysis: rs76830965, near IL12A, OR 0.72 (95% CI: 0.71, 0.73); P = 4.4e−483). Additional effect estimates from three independent cohorts with more specific phenotyping and specific study characteristics support many of these findings. In silico functional analyses provide evidence for a role of T cell regulation in the aetiology of mouth ulcers. These results provide novel insight into the pathogenesis of a common, important condition.

Oral ulcerations are sores of the mucous membrane of the mouth and highly prevalent in the population. Here, in a genome-wide association study, the authors identify 97 loci associated with mouth ulcers highlighting genes involved in T cell-mediated immunity and T_H1 responses.

Mucosal Lesions in an Allergy Practice

The diagnosis and treatment of mucosal disease with an allergic pathogenesis are challenging. Oral allergy is often a hypersensitivity reaction with variable symptoms and physical exam findings. Clinical diagnosis requires a history of prior allergen exposure, a delay from exposure to clinical findings, and improvement following allergen removal. The past decades have seen great contributions to the field of oral allergy. The aim of this review is to provide an approach to the diagnosis and treatment of oral dermatologic disease with a focus on diseases with an investigated allergic pathogenesis.

Etiopathogenesis of recurrent aphthous stomatitis and the role of immunologic aspects: literature review

Recurrent aphthous stomatitis (RAS; recurrent aphthous ulcers; canker sores) belongs to the group of chronic, inflammatory, ulcerative diseases of the oral mucosa. Up to now, the etiopathogenesis of this condition remains unclear; it is, however, considered to be multifactorial. The results of currently performed studies indicate that genetically mediated disturbances of the innate and acquired immunity play an important role in the disease development. Factors that modify the immunologic response in RAS include: food allergies, vitamin and microelement deficiencies, hormonal and gastrointestinal disorders (e.g., celiac disease, Crohn’s disease, ulcerative colitis), some viral and bacterial infections, mechanical injuries and stress. In this paper, we presented the main etiopathogenetic factors of RAS with a special emphasis on the mechanisms of the immune response modification. Moreover, we discussed the crucial clinical symptoms and types of RAS together with epidemiologic data based on the current medical literature reports and our own observations.

Assessment of the serum paraoxonase activity and oxidant/antioxidant status in patients with recurrent aphthous stomatitis

OBJECTIVES

Several studies have indicated that recurrent aphthous stomatitis (RAS) is associated with oxidative stress. The aim of this study was to investigate serum paraoxonase (PON) activity and oxidant/antioxidant status in patients with RAS.

DESIGN AND METHODS

Thirty-one patients with RAS and 31 healthy controls were enrolled. Serum PON1 and arylesterase activities, total antioxidant capacity, total oxidant status, and oxidative stress index were determined.

RESULTS

Serum total antioxidant capacity levels, PON1, and arylesterase activities were significantly lower in RAS than controls (P < 0.001), while total oxidant status levels and oxidative stress index were significantly higher (P < 0.001). PON1 activity had a significant correlation with high-density lipoprotein cholesterol only (r = 0.482, P < 0.05), while there were no correlations with other lipids (P > 0.05) in patients with RAS.

CONCLUSIONS

Our results indicate that RAS is associated with decreased PON1 activity and increased oxidative stress that plays a crucial role in the pathogenesis of RAS. Further studies on a larger number of patients are needed to verify these results.

The effect of ascorbate on minor recurrent aphthous stomatitis

AIM

Minor recurrent aphthous stomatitis (MRAS) is a common, painful and inflammatory ailment of the oral cavity with juvenile onset and unknown aetiology. The purpose of this study was to evaluate the potential of ascorbate (vitamin C) to reduce the frequency of MRAS and severity of pain.

PATIENTS AND METHODS

Sixteen MRAS patients (9 boys and 7 girls: mean age, 12.0 +/- 2.4 years old) were assigned to take an oral dosage of 2000 mg/m(2)/day ascorbate.

SUBJECTS

Their baseline frequency of outbreaks and the level of pains were compared during the treatment; in addition, a crossover clinical trial was performed. Polymorphonuclear leucocytes play a role in the pathogenesis, and then superoxide anion production was evaluated in prior to ascorbate treatment.

RESULTS

The data indicated a statistically significant 50% reduction in oral ulcer outbreaks and a decline of pain level. Neutrophils were primed for superoxide anion production in the patients with MRAS.

CONCLUSION

Ascorbate may modulate the generation of reactive oxygen species and augment neutrophil apoptosis, which could prevent neutrophil-mediated inflammation. Ascorbate seems to be effective, but the findings of our study were preliminary and it should be re-evaluated with a larger randomized controlled clinical trials.

Silver nitrate cautery in aphthous stomatitis: a randomized controlled trial

BACKGROUND

Aphthous stomatitis is a painful, recurrent disease of the oral mucous membrane. Silver nitrate sticks have been used for a long time to provide pain relief for the duration of an aphthous ulceration, with only one application. Silver nitrate causes chemical cauterization and increases the depth of injury.

OBJECTIVES

To study the effect of chemical cautery with silver nitrate in reducing pain of aphthous ulceration and to determine if this treatment shortens or prolongs healing.

METHODS

In a randomized, patient-blinded, placebo-controlled study, 97 patients with painful minor oral aphthous ulceration were randomized to receive silver nitrate cautery or placebo. The severity of pain was rated on a three-category scale (severe, mild, none) and was recorded each day until the seventh day after the procedure. The lesion size was recorded at the time of the procedure and on the seventh day afterwards. In the treatment group, the ulcer was gently painted with a silver nitrate stick until it turned white. In the placebo group, the ulcer was gently painted with a placebo stick.

RESULTS

In the treatment group, 33 of 47 patients (70%) evaluated and in the placebo group, four of 38 patients (11%) evaluated had reduction in severity of pain 1 day after the procedure. The difference was statistically significant (P < 0.001). On the seventh day after the procedure, the ulcers were completely re-epithelialized in 39 patients (83%) in the treatment group and in 34 patients (89%) in the placebo group. The difference was not statistically significant (P = 0.39).

CONCLUSIONS

The results of our study showed that one application of silver nitrate can decrease the severity of pain in aphthous ulceration without significantly shortening or prolonging healing time. We did not observe any side-effects in our study. The effect is rapid and lasts for the duration of the lesion. The treatment is simple and cost-effective in patients with infrequent recurrences.

Recurrent aphthous ulcers today: a review of the growing knowledge

Recurrent aphthous ulcers represent a very common but poorly understood mucosal disorder. They occur in men and women of all ages, races and geographic regions. It is estimated that at least 1 in 5 individuals has at least once been afflicted with aphthous ulcers. The condition is classified as minor, major, and herpetiform on the basis of ulcer size and number. Attacks may be precipitated by local trauma, stress, food intake, drugs, hormonal changes and vitamin and trace element deficiencies. Local and systemic conditions, and genetic, immunological and microbial factors all may play a role in the pathogenesis of recurrent aphthous ulceration (RAU). However, to date, no principal cause has been discovered. Since the aetiology is unknown, diagnosis is entirely based on history and clinical criteria and no laboratory procedures exist to confirm the diagnosis. Although RAU may be a marker of an underlying systemic illness such as coeliac disease, or may present as one of the features of Behcet's disease, in most cases no additional body systems are affected, and patients remain otherwise fit and well. Different aetiologies and mechanisms might be operative in the aetiopathogenesis of aphthous ulceration, but pain, recurrence, self-limitation of the condition, and destruction of the epithelium seem to be the ultimate outcomes. There is no curative therapy to prevent the recurrence of ulcers, and all available treatment modalities can only reduce the frequency or severity of the lesions.

Oxidant/antioxidant status in patients with recurrent aphthous stomatitis

Recurrent aphthous stomatitis (RAS) is recognized as one of the most common oral mucosal diseases worldwide. The aim of this study was to determine the oxidant/antioxidant status in erythrocyte and plasma samples from patients with RAS in comparison with healthy controls. Twenty-two patients with RAS and 23 healthy controls were recruited. Superoxide dismutase, glutathione peroxidase (GSHPx) and catalase (CAT) activities, and malondialdehyde (MDA) and antioxidant potential (AOP) levels were measured in plasma and erythrocytes from patient with RAS and controls. We found decreased CAT and GSHPx activities and AOP levels in the erythrocytes, and decreased AOP and increased MDA plasma levels in patients with RAS in comparison with control subjects. In summary, this study demonstrated that enzymatic and nonenzymatic antioxidant defence systems are impaired in patients with RAS.

Recurrent aphthous stomatitis

Recurrent aphthous stomatitis remains a commonly occurring cause of oral pain and ulceration. Although the ulcerations of RAS are multifactorial and of unknown cause, recognition of the role of patient and environmental factors may be helpful in developing recommendations for treatment and prevention of future ulcers.

Glucocorticosteroids and oral medicine

The article deals with the use of glucocorticosteroids in the treatment of the oral manifestations of Systemic Lupus Erythematosus (SLE), Discoid Lupus Erythematosus (DLE), Rheumatoid Arthritis (RA) in the temporomandibular joint, Pemphigus Vulgaris, Pemphigoid, Erythema Multiforme Exudativum (EME), Lichen Planus (LP), and Recurrent Aphthous Ulcerations (RAU). The benefit from steroids is discussed on the basis of current knowledge of etiology and pathogenesis of the various disorders. All of them are characterized by inflammation which appears secondary to a hypersensitivity reaction against autocomponents. Glucocorticoids do not interfere with the primary disease mechanisms. But it is concluded from the literature, that because of anti-inflammatory and immunosuppressive effects of the hormones, it seems reasonable to profit from steroids as palliatives in acute phases of the diseases and/or as long-term suppressors of the general host defense.

Stereologic analysis of leukocyte infiltration in oral ulcers of developing Mikulicz aphthae

Biopsy specimens of 1- to 7-day-old oral ulcers from patients with minor (Mikulicz), herpetiform, and Behcet's aphthae and of nonulcerated oral mucosa of aphthous patients were subjected to a quantitative, stereologic, electron microscopic analysis of the connective tissue infiltrate residing both at the center of and lateral to the ulcers. The data representing volume fractions and the numerical density of cellular and other infiltrate components demonstrated that (1) the infiltrate under the epithelium lateral to the ulcer is different from that at the ulcer's center, (2) at both sites, composition of the gross infiltrate does not change with age of the ulcer, (3) a large population of leukocytes (about 18% in the lateral and 23% in the central region) belong to the monocyte/macrophage series, (4) blast-forming T-lymphocytes are consistently present, blast-forming B-lymphocytes and plasma cells are very rare, and (5) mast cells are several times more numerous than in normal mucosa. In a comparison of the infiltrates of Mikulicz aphthae with those of herpetiform and Behcet's ulcers, it appears that the pathogenesis of the various oral ulcerations may well be diverse.