To assess the clinical features of primary Sjgren's syndrome (pSS) in childhood and adult patients to understand the differences between them.
Data of 21 childhood and 400 adult patients with definite primary Sjgren's syndrome were analyzed retrospectively.
In adult patients, initial clinical symptoms were various, dry mouth and dry eyes, arthritis and arthralgia, parotid swelling, renal tubular abnormalities (RTA) were more common. Compared with adult patients, RTA, parotid swelling and rash were more common in childhood, pulmonary abnormalities and neurologic system involvement were less common. The frequency of renal tubular abnormalities (52.4%) and rash (47.6%) in childhood pSS were higher than those of adults, but the frequencies of dry eyes (61.0%) and pulmonary interstitial fibrosis (25.2%) in adults pSS were higher than those in childhood (P < 0.01); serum rheumatoid factor (RF) and gamma-globulin were higher in all childhood patients (P < 0.01). Anti-nuclear antibody (ANA), anti-SSA and anti-SSB antibodies, and IgG were significantly higher in childhood cases than in adult patients (P < 0.05 or 0.01).
The major clinical characteristics of childhood pSS cases included: (1) RTA, parotid swelling and rash which appeared earlier, but dry mouth and dry eyes appeared later and were mild. (2) The frequency of pulmonary abnormalities, nervous system involvement and Raynaud's phenomenon were less commonly seen. (3) Positivity of RF, anti-SSA and anti-SSB antibodies, and serum IgG were higher.