Discussion:

Psoriasis is a chronic autoimmune skin condition that leads to rapid skin cell production, resulting in scaling and inflammation, and is often linked with other autoimmune diseases, including RA and SLE5. In patients with rhupus, psoriasis can exacerbate the complexity of treatment, as both RA and SLE may influence the severity and presentation of skin lesions. Moreover, psoriasis can also lead to psoriatic arthritis (PsA), an inflammatory arthritis affecting some individuals with psoriasis, further complicating the clinical picture6. Managing rhupus with psoriasis requires a careful and tailored approach, considering the overlapping symptoms and potential for multi-organ involvement, as seen in patients with systemic vasculitis7. The pathophysiology of Rhupus syndrome involves immune-mediated mechanisms characteristic of both RA and SLE, including the production of autoantibodies and systemic inflammation. Anti-cyclic citrullinated peptide (Anti-CCP) and rheumatoid factor (RF) are biomarkers commonly used in diagnosing RA. At the same time, antinuclear antibodies (ANA) and anti-double stranded DNA (anti-dsDNA) are hallmark features of SLE. However, in Rhupus, these markers often overlap, making it difficult to distinguish between RA and SLE early in the disease process8. This case was initially underscored due to psoriasis, which neglected the need to evaluate other causes of arthritis further. But eventually, thorough examination & lab workup lead to the correct etiology of arthritis. Since DMARD “Apremilast” didn’t show any response, it came to our suspicion that something else pathophysiology must work in this patient. Overlapping features of rheumatoid arthritis and SLE and some non-specific systematic findings made this case more complex. Rhupus is a rare disease with no established criteria or guidelines to treat. We want to notify this case to warrant more attention from policymakers and clinicians to get insights to implement this future research. Our current literature notifies that treatment typically involves a combination of medications and lifestyle changes to manage symptoms and improve quality of life. However, the exact etiology and triggers of rhupus remain unknown, with genetic, immunological, hormonal, and environmental factors potentially playing a role9,10. Author Contribution:Asif Amin: Conceptualization, Data curation, Writing – review and editingZahin Shahriar: Methodology, Formal analysis, Writing – original draftMinhajul Hossain: Project administration, SupervisionRahatul Ishakh: Investigation, SoftwareShah Tanvir: Validation, Resources, Visualization