Overlap-Syndrome — A Rare Combination of Three Autoimmune Pathologies

The improvement of diagnostic methods and the possibilities of modern medicine lead to a deeper study of autoimmune pathology. In clinical practice, cases of a combined course of two or more immunological diseases have become increasingly common, which is called the term “overlap-syndrome” or “crossroads syndrome”. There is still no data on the specific causes of the overlap-syndrome, among the most likely versions is a combination of genetic changes, including the diversity of human leukocyte antigen (HLA) alleles, with external trigger factors. The features of this syndrome are the difficulties of differential diagnostic search due to the variety of symptoms. Untimely verification of the diagnosis leads to a late appointment of treatment and a less favorable long-term prognosis. In clinical practice, a combination of systemic scleroderma or systemic lupus erythematosus with rheumatoid arthritis is most common. This article provides an example of the overlap-syndrome in a 69–year-old patient with three autoimmune pathologies — systemic scleroderma, CABG, and primary biliary cholangitis with multiple organ damage (lungs, skin, gastrointestinal tract, salivary glands, blood vessels, and nervous system). The patient had a long history of Raynaud’s syndrome, as well as primary biliary cholangitis. Two years before the treatment, the patient was diagnosed with Sjogren’s syndrome, and in 2025, a limited form of systemic scleroderma. Thus, during her lifetime, the patient developed 3 autoimmune pathologies included in the overlap-syndrome. Specialists should pay increased attention to patients with a long history of rheumatological disease in order to detect other autoimmune pathologies in a timely manner and initiate timely treatment to prevent the development of complications.

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