Aim
This study investigated the common initial clinical presentations of primary Sjögren's syndrome (pSS) with interstitial lung disease (ILD) and explored differences between sicca and non‐sicca onset pSS‐ILD patients.
Method
A total of 1341 SS patients hospitalized between 2003 and 2012 were retrospectively reviewed. Of them, 102 were analyzed and recruited to examine the differences between non‐sicca and sicca onset.
Results
Fifty‐one percent of pSS‐ILD patients presented with non‐sicca onset. Although the mean diagnosis time was equal, only 4% of non‐sicca onset patients were diagnosed with pSS at onset versus 34% with sicca onset (P = 0.000). Hyperglobulinemia, elevated rheumatoid factor (RF) titer, and anti‐SSA and/or anti‐SSB presence were less predominant in patients with non‐sicca onset (immunoglobulin G, 16 [12–21] vs. 21 [15–28] g/L, P = 0.032; RF, 22 [20–171] vs. 104 [20–237] IU/mL, P = 0.048; anti‐SSA and/or anti‐SSB presence, 33% vs. 72%, P = 0.000). The usual interstitial pneumonia pattern was more commonly seen in non‐sicca onset patients (20.0% vs. 14.3%). The high‐resolution computed tomography score was higher (12 [88–15] vs. 8 [5–13], P = 0.070) and predicted total lung capacity and forced vital capacity were lower (87 ± 23% vs. 97 ± 20%, P = 0.050; 88 ± 28% vs. 100 ± 27%, P = 0.089) in non‐sicca patients.
Conclusion
Non‐sicca is a common initial manifestation in pSS‐ILD. Anti‐SSA presence, elevated RF titer and hyperglobulinemia were less predominant, and pulmonary complications were more progressive and severe in non‐sicca onset patients than sicca onset patients.