Background Limited research exists on the laboratory characteristics of coexistent primary biliary cholangitis (PBC) and Sjögren’s syndrome (SS). This study aimed to investigate the laboratory risk factors for the coexistence of PBC in patients with SS. Methods Eighty-two patients with coexistent SS and PBC (median age 52.50 years) and 82 age- and sex-matched SS controls were retrospectively enrolled between July 2015 and July 2021. The clinical and laboratory characteristics of the two groups were compared. Laboratory risk factors for the coexistence of PBC in patients with SS were analyzed using logistic regression analysis. Results Both groups had a similar prevalence of hypertension, diabetes, thyroid disease, and interstitial lung disease. Compared with the SS group, patients in the SS + PBC group had higher levels of liver enzymes, immunoglobulins M (IgM), G2, and G3 (P < 0.05). The percentage of patients with an antinuclear antibody (ANA) titre > 1:10000 in the SS + PBC group was 56.1%, higher than that in the SS group (19.5%, P < 0.05). Additionally, cytoplasmic, centromeric, and nuclear membranous patterns of ANA and positive anti-centromere antibody (ACA) were observed more frequently in the SS + PBC group (P < 0.05). Logistic regression analysis showed that elevated IgM levels, high ANA titre, cytoplasmic pattern, and ACA were independent risk factors for PBC coexistence in SS. Conclusions In addition to established risk factors, elevated IgM levels, positive ACA, and high ANA titre with cytoplasmic pattern provide clues to clinicians for the early screening and diagnosis of PBC in patients with SS.

Background There is limited research on the laboratory characteristics of coexistent primary biliary cholangitis (PBC) and Sjögren's syndrome (SS). This study aimed to investigate the laboratory risk factors for the coexistence of PBC in patients with SS. Methods Eighty-two patients with coexistent SS and PBC (median age 52.50 years) and 82 age- and sex-matched SS controls were retrospectively enrolled between July 2015 and July 2021. The clinical and laboratory characteristics of the two groups were compared. Laboratory risk factors for the coexistence of PBC in patients with SS were analyzed using logistic regression analysis. Results Both groups had a similar prevalence of hypertension, diabetes, thyroid disease, and interstitial lung disease. Compared with the SS group, patients in the SS + PBC group had higher levels of liver enzymes, immunoglobulins M (IgM), G2, and G3 (P < 0.05). The percentage of patients with an antinuclear antibody (ANA) titer > 1:10000 in the SS + PBC group was 56.1%, higher than that in the SS group (19.5%, P < 0.05). In addition, cytoplasmic, centromeric, and nuclear membranous patterns of ANA and positive anti-centromere antibody (ACA) were observed more frequently in the SS + PBC group (P < 0.05). Logistic regression analysis showed that elevated IgM levels, high ANA titer, cytoplasmic pattern, and ACA were independent risk factors for PBC coexistence in SS. Conclusion In addition to established risk factors, elevated IgM levels, positive ACA, and high ANA titer with cytoplasmic pattern also provide clues to clinicians for the early screening and diagnosis of PBC in patients with SS.

Introduction: Progressive pseudorheumatoid dysplasia (PPRD) is a rare autosomal recessive genetic disease caused by mutations in the Wnt1-inducible signaling pathway protein 3 gene. PPRD is considered a noninflammatory disease, and involvement of the sacroiliac joint and hip arthritis have not been reported previously. Patient concerns: We report a case of PPRD in an 11-year-old boy, who presented with bilateral pain and swelling in the knees, elbows, and ankles, and bilateral pain without swelling in the shoulders, wrists, knuckles, and proximal and distal interphalangeal joints for the past 5 years. He had been misdiagnosed with juvenile idiopathic arthritis for more than 6 years. Diagnosis: The correct PPRD diagnosis was made using whole-exome sequencing for Wnt1-inducible signaling pathway protein 3 gene mutations (c.589 + 2T>C and c.721T>G; both mutations have rarely been reported) and magnetic resonance imaging examination; moreover, the latter showed inflammation of the sacroiliac joint and hip joint. Intervention: The patient was administered supplemental calcium, active vitamin D, and glucosamine sulfate. Outcome: The patient experienced alleviation of joint pain following treatment initiation; however, joint motion improvement was not obvious. Above all, the long-term use of biologic or targeted synthetic disease-modifying antirheumatic drugs in the future was avoided. Conclusion: The findings of the inflammatory aspects in PPRD will enrich our understanding of this rheumatological disease.