Presymptomatic autoantibodies in Sjögren's syndrome: what significance do they hold for the clinic?

Association between a History of herpes zoster and the risk of Sjögren's syndrome: a nationwide, population-based, case-control study

OBJECTIVE

Viral infection is an exogenous factor for Sjögren's syndrome (SS). The relationship between herpes zoster infection and the ensuring risk of SS has remained unclear. This study investigated the association between a history of herpes zoster infection and the risk of SS through a nationwide population-based case-control study.

DESIGN

Retrospective case-control study.

SETTING

General population of Taiwan.

DATA SOURCE

2003-2013 National Health Insurance Research Database of Taiwan.

PARTICIPANTS

We identified all patients with newly diagnosed SS between 1 January 2007 and 31 December 2012 without a history of rheumatoid arthritis or systemic lupus erythematosus as the SS group.

CONTROLS

We randomly selected patients without SS between 1 January 2003 and 31 December 2012 and matched 1:5 with controls based on index year, age and sex.

MAIN OUTCOME MEASURE

Conditional logistic regression analysis to examine the association between a history of herpes zoster and the risk of SS.

RESULTS

The study included 5751 patients with SS and 28 755 matched controls. The risk of SS was significantly associated with a history of herpes zoster (model A (adjusted for Charlson Comorbidity Index (CCI) (excluding connective tissue disease, CTD)): OR 1.89; 95% CI 1.71 to 2.08; model B (adjusted for comorbidities used to calculate CCI (excluding CTD)): OR 1.90; 95% CI 1.72 to 2.10), in particular if the interval from the last visit for herpes zoster infection to the index date was <3 months (model A: OR 3.09; 95% CI 2.20 to 4.34; model B: OR 3.13; 95% CI 2.20 to 4.45). Such associations remained robust using various definitions of herpes zoster.

CONCLUSION

This nationwide, population-based, case-control study revealed a significant association between a history of herpes zoster and the risk of SS.

Early diagnosis and treatment for Sjögren's syndrome: current challenges, redefined disease stages and future prospects

There are some challenges and unmet needs in the early diagnosis and management of Sjögren's syndrome (SjS) such as prominent glandular dysfunction at diagnosis and long diagnostic delay. Those challenges are partly attributed to the lack of a good knowledge of the early stages of SjS, which is a major obstacle to delivering appropriate care to SjS patients. Findings from both clinical and experimental studies suggest the plausibility of a redefined SjS course consisting of 4 stages, which includes initiation stage, preclinical stage, asymptomatic SjS stage and overt SjS stage. More studies focusing on the pathological processes and changes during the early stages of SjS are needed. To enable early diagnosis and treatment for SjS, more useful biomarkers of the early stages of SjS need to be identified, and individuals at high risk of SjS development need to be identified. Appropriate screening can be performed to facilitate the early diagnosis of SjS among those high-risk individuals.

Activation of Peptidylarginine Deiminase in the Salivary Glands of Balb/c Mice Drives the Citrullination of Ro and La Ribonucleoproteins

The goal of the present study was to determine whether peptidylarginine deiminase PAD2 and PAD4 enzymes are present in Balb/c mouse salivary glands and whether they are able to citrullinate Ro and La ribonucleoproteins. Salivary glands from Balb/c mice were cultured in DMEM and supplemented with one of the following stimulants: ATP, LPS, TNF, IFNγ, or IL-6. A control group without stimulant was also evaluated. PAD2, PAD4, citrullinated peptides, Ro60, and La were detected by immunohistochemistry and double immunofluorescence. PAD2 and PAD4 mRNAs and protein expression were detected by qPCR and Western blot analysis. PAD activity was assessed using an antigen capture enzyme-linked immunosorbent assay. LPS, ATP, and TNF triggered PAD2 and PAD4 expression; in contrast, no expression was detected in the control group (p < 0.001). PAD transcription slightly increased in response to stimulation. Additionally, PAD2/4 activity modified the arginine residues of a reporter protein (fibrinogen) in vitro. PADs citrullinated Ro60 and La ribonucleoproteins in vivo. Molecular stimulants induced apoptosis in ductal cells and the externalization of Ro60 and La ribonucleoproteins onto apoptotic membranes. PAD enzymes citrullinate Ro and La ribonucleoproteins, and this experimental approach may facilitate our understanding of the role of posttranslational modifications in the pathophysiology of Sjögren's syndrome.