Childhood Sjögren's Disease: A Literature Review of an Underrecognized Autoimmune Entity in Pediatric Rheumatology

Childhood Sjögren's disease (cSjD) is a rare and poorly recognized systemic autoimmune disease whose clinical presentation is distinctly different from the adult form of the disease. The present synthesis is an overview of the existing literature that points to a heterogeneous disease profile, meaning recurrent parotitis and extraglandular manifestations rather than typical sicca symptoms in adults (dry eyes and mouth). One challenge in pediatric rheumatology is that not all diagnostic criteria developed in adults, including the American College of Rheumatology/European Alliance of Associations for Rheumatology 2016 criteria, which have low sensitivity in children, can be applied, resulting in considerable delays in diagnosis. Research has established that a significant proportion of children who are identified with cSjD through expert opinion do not fit the standards. Major clinical signs among children consist of frequent parotitis, arthralgia, lymphadenopathy, and a broad spectrum of dysfunction in the hematological, renal, hepatic, and central nervous systems. Life-threatening complications are infrequent but include interstitial lung disease, diffuse alveolar hemorrhage, and B-cell lymphoma. The gap in diagnosis has been addressed by existing studies that aimed at non-invasive measures and novel classification systems. Salivary gland ultrasonography and ultra-high-frequency ultrasonography are emerging tools to assess the inflammation of the glands. New, empirical methods, including the Florida Scoring System, and systematic clinical models, including the three-pathway diagnostic algorithm, have been designed to offer a more precise and standard cSjD assessment. The diagnostic algorithms need to be proven by further research. The management of cSjD lacks a standard practice and is strongly dependent on individual practitioners, who often base it on adult practice. The management is specific to the clinical manifestations, with mild symptoms treated with non-steroidal anti-inflammatory drugs and hydroxychloroquine, and moderate or severe systemic disease and complications treated with corticosteroids, conventional disease-modifying antirheumatic drugs, and biologics such as rituximab. This review highlighted the constitutional symptoms, such as rash, fever, and joint pain (arthralgia), which are common and often present alongside glandular inflammation. Neurological involvement, including psychiatric symptoms, may also occur, further complicating diagnosis and management. There is a very low-quality evidence base on these treatments, with case reports and small series as the main components, underlining the urgent need for collaboration, high-quality research, and creation of pediatric-specific diagnostic criteria as well as treatment guidelines.