Correlations Between Single-Photon Emission Computed Tomography Parameters of Salivary Glands and Dry Eye Tests in Patients With Sjögren's Syndrome

Objective

To evaluate the correlations between Single-Photon Emission Computed Tomography (SPECT) parameters of salivary glands and dry eye parameters in patients with Sjögren's syndrome (SS).

Methods

A total of 28 patients with SS participated in this prospective study. Dry eye assessments include tear film break-up time (TBUT), corneal fluorescein staining scoring (CFS), Schirmer's I test (SIT) examination and SPECT of salivary gland. The following quantitative parameters were derived from SPECT imaging for salivary glands: Uptake index (UI), the time needed to achieve the minimum counts after Vit C stimulation (T_s), and excretion fraction (EF). The relation between the aforementioned parameters and TBUT, CFS and SIT were analyzed with SPSS 22.0 software.

Results

All the 28 eyes of the 28 subjects were examined. The mean SIT was 6.04 ± 4.64 mm/5 min (0–18 mm/5 min); the mean CFS was 3.07 ± 2.65 (0–10) and the mean BUT was 2.11 ± 1.97 s (0–9 s). The mean EF value was 0.52 ± 0.12 (0.26–0.75) in parotid glands and 0.45 ± 0.10 (0.30–0.67) in submandibular glands, respectively. The mean UI value was 9.33 ± 1.68 (6.03–13.20) in parotid glands and 9.92 ± 1.48 (7.08–12.60) in submandibular glands, respectively. The mean T_s (min) was 5.32 ± 3.01 (2.00–12.00) in parotid glands and 11.09 ± 7.40 (2.00- 29.00 min) in submandibular glands, respectively. It was found that EF positively correlates with SIT in patients with SS (r = 0.499 and 0.426 in parotid glands and submandibular glands, with P < 0.05), while no significant correlation was found between the UI, T_s and CFS, TBUT (P > 0.05).

Conclusions

The EF was positively correlated with SIT in patients with SS, it could reflex the dysfunction of salivary glands in SS patients. So, EF may be a valuable parameter for the diagnosis of SS patients with lacrimal gland secretion dysfunction.

Transcriptomic Profile of Genes Encoding Proteins Involved in Pathogenesis of Sjögren's Syndrome Related Xerostomia-Molecular and Clinical Trial

Sjögren’s syndrome (SS) is characterized by xerostomia. We aimed to investigate and compare gene expressions in the labial salivary glands of SS patients with xerostomia SS (sicca) and without xerostomia SS (non-sicca) and of healthy subjects (HS) by means of microarray analysis, and to find genes involved in xerostomia. The study group comprised 11 SS patients (3 SS (sicca) and 8 SS (non-sicca)) and 9 HS. The relative gene expression changes were validated with RT-qPCR in the larger study group. Among the differently expressed genes belonging to the “secretion” ontology group with a fold change >2 and with a p value < 0.05, the Transmembrane P24 Trafficking Protein 10 (TMED10), Protein Disulfide Isomerase Family A Member 4 (PDIA4), Calnexin (CANX), Amyloid Beta Precursor Protein (APP), and Transmembrane BAX Inhibitor Motif Containing 6 (TMBIM6) gene expressions in both SS (sicca) and SS (non-sicca) groups were lower than in HS. Significant correlations were observed between TMED10, PDIA4, and CANX gene expression in SS (sicca) patients compared to the controls. There were no differences between the SS (sicca) and SS (non-sicca) study groups in the expression of the aforementioned genes. Results indicate their role in the endoplasmic reticulum system, their overlapping function and the loss of the APP neuroprotective function in xerostomia. It has a multifactorial origin and can be triggered by disturbances to the various signaling pathways in saliva secretion.

Epidemiology of Sjögren's Syndrome-from an Oral Perspective

Oral symptoms are among the most distressing manifestations for patients with Sjögren's syndrome (SS). The feeling of dry mouth is unpleasant, and hyposalivation may contribute to difficulty in speaking, chewing and swallowing and reduced quality of life. Reduced salivary flow increases the risk for dental caries and problems with prosthetic replacement. It seems that SS is not as frequently occurring as previously anticipated. Population-based prevalence studies on primary SS in Europe, conducted on large background populations and in accordance with the AECG criteria, reported of a prevalence of 1-9 cases per 10,000 people. This gives a combined prevalence of nearly 39/100,000 (~0.04 %). The cause of Sjögren's syndrome is even now not fully understood, and the treatment of oral symptoms is still mostly palliative. Hopefully, useful information will appear from the new methods that are now available for genome wide association studies, epigenetics, DNA methylation studies, and proteomics. Similarly, this is anticipated for the immunological side of the story. The interferon signature, the interferon γ/interferon α mRNA ratio, and CXCL13 are among the proposed biomarkers of active disease. In this review, we provide an update on oral aspects of Sjögren's syndrome with emphasis on the latest publications on these topics.

Usefulness of IgA Anti-α-fodrin Antibodies in Combination with Rheumatoid Factor and/or Antinuclear Antibodies as Substitute Immunological Criterion in Sjögren Syndrome with Negative Anti-SSA/SSB Antibodies

OBJECTIVE

We aimed to evaluate the usefulness of anti-α-fodrin antibodies (AFA) in combination with rheumatoid factor (RF) and/or antinuclear antibodies (ANA) as an alternative immunological criterion for Sjögren syndrome (SS) among patients with negative anti-Ro/La serology.

METHODS

The study included 350 patients (100 with rheumatoid arthritis, systemic lupus erythematosus, and systemic sclerosis, and 50 with primary SS) randomly selected and assessed for SS. All patients were tested for ANA, RF, anti-SSA/SSB, and AFA antibodies. SS diagnosis was made on a clinical basis by 2 rheumatologists based on the 6-item screening questionnaire, Schirmer-I test, nonstimulated whole salivary flow rate, fluorescein staining test, autoantibodies, lip biopsy, and medical chart review. Non-SS was defined as lack of clinical diagnosis and not fulfilling the American-European Consensus Group classification criteria and the American College of Rheumatology (ACR) criteria. The ACR criteria were applied substituting the immunological criteria as follows: (1) RF plus ANA > 1:320, (2) RF plus AFA, (3) ANA > 1:320 plus AFA, (4) RF alone, and (5) 2 positive tests out of RF, ANA > 1:320, or AFA. We estimated the sensitivity, specificity, positive predictive value, negative predictive value, and likelihood ratio positivity with 95% CI for each criterion.

RESULTS

There were 236 patients (67%) who tested negative for anti-SSA/SSB antibodies, of whom 65 (27.5%) were clinically diagnosed as SS, and 149 (63%) with non-SS. RF + AFA and ANA + AFA performed similarly to RF + ANA > 1:320. The model 2 out of 3 of RF, ANA, or AFA improved the sensitivity from 56.9% to 70.7%, although the specificity decreased.

CONCLUSION

The combination AFA + RF, AFA + ANA > 1:320, or at least 2 out of 3, performed well as a proxy immunological test for patients with SS and negative Ro/La serology.

A Point-Scoring System for the Clinical Diagnosis of Sjögren's Syndrome Based on Quantified SPECT Imaging of Salivary Gland

Objective

To establish a point-scoring diagnostic system for Sjögren's syndrome (SS) based on quantified SPECT imaging of salivary gland, and evaluate its feasibility and performance compared with 2002 AECG criteria and 2012 ACR criteria.

Methods

213 patients with suspected SS enrolled in this study. The related clinical data of all patients were collected. All patients were evaluated and grouped on a clinical basis and posttreatment follow-up by rheumatology specialists as the unified standard (SS group with 149 cases and nSS group with 64 cases). From SPECT imaging of salivary gland, T_max, UI_max, T_s and EF_s were derived for bilateral parotid and submandibular glands, and compared between the groups. A point-scoring diagnostic system for SS was established based on the quantified SPECT imaging of salivary gland. We estimated the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy for the new diagnostic system, compared with 2002 AECG criteria and 2012 ACR criteria.

Results

When 7.0 was used as the cut-off point, the sensitivity, specificity, PPV, NPV and accuracy for the new point-scoring system in diagnosing SS were 89.93% (134/149), 93.75% (60/64), 97.10% (134/138), 80.00% (60/75) and 91.08% (194/213), respectively. The new point-scoring diagnostic system based on quantified SPECT imaging of salivary gland keeps the specificity comparatively to 2002 AECG criteria and 2012 ACR criteria, but improves the sensitivity significantly (P<0.01).

Conclusion

The new point-scoring diagnostic system for SS based on quantified SPECT imaging of salivary gland may be superior to 2002 AECG criteria and 2012 ACR criteria, with higher sensitivity and similar specificity in the diagnosis of SS. Additionally, it also has good feasibility in the clinical settings.