Immunological methods for the diagnosis of oral mucosal diseases

Oral lesions of systemic lupus erythematosus: A collaborative Latin American study

BACKGROUND

Systemic lupus erythematosus (SLE) is a multifactorial autoimmune disease that may affect the oral mucosa. The variable spectrum of oral lesions observed in SLE can pose challenges in diagnosis, particularly when the lesions occur in isolation. The aim of this study was to describe the oral lesions occurring in patients with SLE from Latin America.

METHODS

This collaborative record-based study involving 11 oral and maxillofacial pathology and medicine services across Venezuela, Argentina, Chile, Brazil, and Mexico describes the clinicopathological profile of SLE-related oral lesions.

RESULTS

Seventy patients with SLE and oral lesions were included in the study. The majority were females (75.7%; female/male ratio: 3.1:1) and white (62.1%), with a mean age of 38.4 years (range: 11-77 years). The most common site of oral lesions was the hard/soft palate (32.0%). Clinically, oral lesions predominantly presented as ulcers (26.6%), erosions (26.6%), and white lesions (23.4%). Isolated oral lesions occurred in 65.2% of individuals, while cutaneous manifestations occurred in 80.3%. The main clinical diagnostic hypothesis in 71.4% of cases was an immune-mediated disease. Oral biopsies followed by histopathological analysis were performed in 50 cases.

CONCLUSION

Oral lesions of SLE exhibit a variety of clinical and histopathological features. A key point in diagnosis is that unusual oral changes without an obvious local cause may indicate a possible systemic condition presenting with oral lesions. A multidisciplinary approach, which includes regular oral examination, is warranted to identify oral lesions and provide treatment.

Direct immunofluorescence cannot be used solely to differentiate among oral lichen planus, oral lichenoid lesion, and oral epithelial dysplasia

Background/purpose

Some red and white lesions may have similar manifestations, making them difficult to be diagnosed. A direct immunofluorescence (DIF) assay can assist in making a final diagnosis of oral lichen planus (OLP). The aim of this study was to evaluate and compare the DIF profile in patients who had the clinical presentations of OLP and were histopathologically diagnosed with OLP, OLL (oral lichenoid lesion), or OED (oral epithelial dysplasia).

Materials and methods

The data were obtained from the medical records of 136 patients with the clinical presentations of OLP. Demographic information, histopathological diagnosis, malignant transformation, and DIF results were collected and analyzed.

Results

In this study, 117 patients (86.0%) were DIF-positive, while 19 patients (14.0%) were DIF-negative. The highest DIF-positivity rate was in the OLP group (88.9%) followed by the OLL (83.7%), and the OED groups (81%). There were no significant differences in DIF-positivity rate, type of immunoreactants, location, or interpretation among these groups. Shaggy fibrinogen at the basement membrane zone (BMZ) was the most common DIF pattern in all groups.

Conclusion

The DIF assay alone cannot be regarded as sufficient evidence for OLP, OLL, and OED differentiation. A histopathological examination is required to determine the presence of epithelial dysplasia or malignancy. To diagnose dysplastic lesions with the clinical manifestations of OLP, careful clinicopathologic correlation is mandatory. Due to the lack of scientific evidence to identify the primary pathology and the ongoing malignancy risk of epithelial dysplasia, meticulous long-term follow-up plays a crucial role in patient management.

Differential genotypes of TNF-α and IL-10 for immunological diagnosis in discoid lupus erythematosus and oral lichen planus: A narrative review

Discoid lupus erythematosus and oral lichen planus are chronic systemic immune system-mediated diseases with unclear etiology and pathogenesis. The oral mucosa is the common primary site of pathogenesis in both, whereby innate and adaptive immunity and inflammation play crucial roles. The clinical manifestations of discoid lupus erythematosus on the oral mucosa are very similar to those of oral lichen planus; therefore, its oral lesion is classified under oral lichenoid lesions. In practice, the differential diagnosis of discoid lupus erythematosus and oral lichen planus has always relied on the clinical manifestations, with histopathological examination as an auxiliary diagnostic tool. However, the close resemblance of the clinical manifestations and histopathology proves challenging for accurate differential diagnosis and further treatment. In most cases, dentists and pathologists fail to distinguish between the conditions during the early stages of the lesions. It should be noted that both are considered to be precancerous conditions, highlighting the significance of early diagnosis and treatment. In the context of unknown etiology and pathogenesis, we suggest a serological and genetic diagnostic method based on TNF-α and IL-10. These are the two most common cytokines produced by the innate and adaptive immune systems and they play a fundamental role in maintaining immune homeostasis and modulating inflammation. The prominent variability in their expression levels and gene polymorphism typing in different lesions compensates for the low specificity of current conventional diagnostic protocols. This new diagnostic scheme, starting from the immunity and inflammation of the oral mucosa, enables simultaneous comparison of discoid lupus erythematosus and oral lichen planus. With relevant supportive evidence, this information can enhance physicians’ understanding of the two diseases, contribute to precision medicine, and aid in prevention of precancerous conditions.

Oral lichen planus identification by mid-infrared spectroscopy of oral biofluids: A case-control study

BACKGROUND AND AIMS

This study aims to access the effectiveness of mid-infrared (MIR) spectroscopy on the identification of the reticular form of OLP, following the assessment of gingival crevicular fluid (GCF) and oral mucosa transudate (OMT).

MATERIAL AND METHODS

The trial follows a case-control design. Samples were characterized through MIR spectroscopy and chemometric tools were applied to distinguish between case and control participants, further identifying the spectral regions with the highest contribution to the developed models.

RESULTS

MIR spectroscopy was capable to discriminate between OLP patients and controls with 95.1% and 85.4% of correct predictions, regarding GCF and OMT samples, respectively. Additionally, the spectral regions mostly contributing to the successful prediction were identified, and possibly related with the distinctive presence of amino acids/proteins and oxidative stress mediators in oral biofluids, supporting the role of the immune-inflammatory activation on OLP etiology and disease course.

CONCLUSION

MIR spectroscopy analysis of GCF and OMT may be regarded as an innovative, non-invasive, low cost and sensitive technique, contributing to the identification of the reticular from of OLP.

Direct immunofluorescence staining patterns compared between oral and cutaneous lichen planus

This retrospective study was aimed to investigate direct immunofluorescence (DIF) finding between oral and cutaneous lichen planus (LP). Of 147 cases with a definite diagnosis of LP by clinical and histological criteria, 125 cases (85%) demonstrated the positive immunofluorescence findings. The positive yields were significantly lower in oral LP (79.3%) than in cutaneous LP (93.3%). There were 87 (59.2%) oral and 60 (40.8%) cutaneous specimens, respectively. Immunoreactants deposited at the dermoepidermal junction (DEJ) significantly more often in oral than in cutaneous LP. Fibrin deposition with shaggy pattern at the DEJ was significantly higher in oral than in cutaneous LP. Deposition of immunoreactants at the colloid bodies (CB) with or without DEJ was significantly greater in cutaneous than in oral LP. Immunoglobulin M at the CB was commonly detected in both groups. We proposed that fibrin deposition with shaggy pattern at the DEJ was the best diagnostic indicator of oral LP.

Genomic characterization of four Escherichia coli strains isolated from oral lichen planus biopsies

Oral lichen planus (OLP) is a chronic T cell-mediated inflammatory disease that affects the mucus membrane of the oral cavity. We previously proposed a potential role of intracellular bacteria detected within OLP lesions in the pathogenesis of OLP and isolated four Escherichia coli strains from OLP tissues that were phylogenetically close to K-12 MG1655 strain. We sequenced the genomes of the four OLP-isolated E. coli strains and generated 6.71 Gbp of Illumina MiSeq data (166–195x coverage per strain). The size of the assembled draft genomes was 4.69 Mbp, with a GC content of 50.7%, in which 4360 to 4367 protein-coding sequences per strain were annotated. We also identified 368 virulence factors and 53 antibiotic resistance genes. Comparative genomics revealed that the OLP-isolated strains shared more pangenome orthologous groups with pathogenic strains than did the K-12 MG1655 strain, a derivative of K-12 strain isolated from human feces. Although the OLP-isolated strains did not have the major virulence factors (VFs) of the pathogenic strains, a number of VFs involved in adherence/invasion, colonization, or systemic infection were identified. The genomic characteristics of E. coli first isolated from the oral cavity would benefit future investigations on the pathogenic potential of these bacteria.