Barriers to translational research in Sjögren's syndrome with childhood onset: challenges of recognising and diagnosing an orphan rheumatic disease.

Sjögren's syndrome was considered for many years a disease of adulthood, characterised by immune infiltration of exocrine glands, leading to dryness (eg, dry mouth and eyes), which is a cardinal symptom. As of the last 20 years, it became apparent that although the disease is very rare in children, its clinical presentation differs from that of adults, posing substantial challenges to the recognition, diagnosis, and classification of patients with childhood-onset Sjögren's syndrome. This Viewpoint explores comparative classification criteria for children (not validated) and adults with Sjögren's syndrome, as well as differences in the clinical presentation of childhood-onset versus adult-onset Sjögren's syndrome, offering ideas about how we can improve the diagnosis of Sjögren's syndrome in children. A review of the role of medical history and clinical assessment, serology, glandular function assessment, and imaging, as well as salivary and lachrymal gland biopsy in the diagnosis of children with Sjögren's syndrome is included. Additionally, we provide suggestions about further research and registry data collection that is required to address the unmet needs of these patients.