Despite not being included in this systematic review, psychiatric manifestations associated with childhood-onset SS have been also reported.28 Studies have shown that low complement C3, male sex, anti-SSA, and kidney and pulmonary involvement might be associated with neurological involvement in adults with SS.29,30 However, in published cases of childhood-onset SS, fever was the most common extraglandular feature, and other involvements such as kidney or lung involvement were rarely reported. This evidence concerns the gene C3 and Childhood onset.