RESUMO
INTRODUCTION: Primary Sjögren's syndrome (pSS) is an autoimmune disorder primarily affecting salivary and lacrimal glands, although about 40% of patients experience systemic complications. In this setting, the identification of patient phenotypes characterized by increased risk of extra-glandular involvement still represents an unmet need. AREAS COVERED: The aim of this paper is to review the scientific evidence on the utility of salivary gland biopsies in pSS, emphasizing their role in defining prognosis. In latest years, research focused on disease-specific clinical, serological, or histological features able to categorize patient prognosis. Among histopathological features, focus score and ectopic germinal centers exhibit associations with glandular and extraglandular manifestations, including higher rates of lymphomagenesis. EXPERT OPINION: Pathological characterization of salivary glands provides information that go beyond a mere diagnostic or classification utility, providing insights for a stratification of disease severity and for predicting systemic manifestations. Thus, a salivary gland biopsy should be offered to all patients and included in routine practice, even when not strictly required for diagnostic purposes. More advanced analysis techniques of the tissue, including immunohistochemistry and 'omics' should be further explored in longitudinal studies to boost the ability to further stratify and predict disease evolution.
RESUMO
Primary Sjögren's syndrome (pSS) is a complex disabling systemic autoimmune disorder. The hallmark of pSS is the T-cell-mediated hyperactivation of B-cells, evolving from asymptomatic conditions to systemic complications and lymphoma development. On tissue level, the typical feature is the lymphocytic infiltration of the salivary gland by B-, T- and antigen presenting cells, as mirrored by the diagnostic cornerstone role of minor salivary gland (MSG) biopsy. B-cells show multiple possible roles in disease pathogenesis, from autoantibody production, to antigen presentation, and cytokine production. B-cells hyperactivation is supported by genetic risk factors, T-cell dependent and independent mechanisms, and the presence of different pathogenic B-cell subsets must be reminded.Many aspects have been investigated in the last year regarding genetic and epigenetics, B- and T-cell role in pSS pathogenesis, their interaction with salivary gland epithelial cells (SGECs) and in their direct or indirect use as biomarkers and predictors of disease development, activity, and lymphomagenesis.In this review, following the others of this series, we will summarise the most recent literature on pSS pathogenesis and clinical features focusing in particular on new insights into pSS molecular stratification and therapeutic advances in the era of precision medicine.