The diagnostic dilemma of isolated, initially mild but progressive liver enzyme elevation as an initial manifestation of childhood-onset primary Sjögren’s syndrome: a case report and literature review

Abstract Background Childhood-onset primary Sjögren’s syndrome (pSS) is a rare autoimmune disease with heterogeneous clinical manifestations. Hepatic involvement has been infrequently reported in pediatric pSS and is particularly rare as the initial presenting feature. Case presentation A 9-year-old boy presented with a 2-year history of isolated persistent liver enzyme elevation, with progressive biochemical worsening during the preceding 5 months. During approximately the first 20 months, elevations of alanine aminotransferase and gamma-glutamyl transferase were mild and consistently remained below twice the upper limit of normal. Creatine kinase levels were repeatedly normal, with no clinical evidence of significant muscle involvement. Investigations did not identify an infectious or drug-related cause, and autoimmune liver disease-associated autoantibodies were negative. Abdominal ultrasonography showed mild hepatic steatosis. Strongly positive anti-SSA, anti-SSB, and anti-Ro52 antibodies, together with focal lymphocytic sialadenitis (focus score ≥ 1 per 4 mm²), supported a clinical diagnosis of childhood-onset pSS. Liver biopsy and magnetic resonance cholangiopancreatography were not performed. Following treatment with tofacitinib, hydroxychloroquine, and short-term diammonium glycyrrhizinate, liver biochemical tests normalized and remained within reference ranges during 8 months of follow-up. Conclusion Isolated persistent liver enzyme elevation may precede recognition of childhood-onset pSS, even in the absence of sicca symptoms. However, the hepatic etiology remained incompletely characterized, and a causal relationship with pSS could not be established. Continued follow-up is needed to reassess alternative or coexisting diagnoses.