Methotrexate (MTX) remains the anchor drug in the management of rheumatoid arthritis (RA). However, its clinical use is frequently limited by intolerance, leading to dose reduction or discontinuation. In addition, oral MTX exhibits pharmacokinetic limitations, including dose-dependent absorption and reduced bioavailability at higher doses, which may compromise therapeutic efficacy. Subcutaneous (SC) MTX has emerged as a strategy to overcome these limitations by providing more consistent bioavailability and potentially improved tolerability. Evidence suggests that switching from oral-to-SC MTX may improve gastrointestinal (GI) intolerance and support treatment persistence, whereas evidence for improved disease control or reduction of serious MTX-related toxicity remains limited. Recent Japanese studies suggest the potential utility of this approach at MTX doses commonly used in Japan, although evidence for the superiority of SC MTX over oral MTX in low-dose settings remains limited. This narrative review summarizes current evidence on MTX intolerance and oral-to-SC route switching in RA, with a focus on practical strategies for treatment optimization. Overall, oral-to-SC MTX switching may represent an important option to improve GI intolerance and support treatment persistence in patients with RA.

Dysphagia is a common and clinically significant complication in idiopathic inflammatory myopathies (IIM), contributing to aspiration pneumonia, malnutrition, and reduced quality of life. However, its prognostic significance in terms of survival and swallowing outcomes remains unclear. A narrative review was conducted using PubMed to identify relevant studies published between January 2000 and April 2026. Dysphagia in IIM is associated with increased mortality, primarily due to aspiration-related complications and underlying disease severity. Emerging evidence indicates that this association may be modified by the presence of malignancy, particularly in dermatomyositis. Swallowing outcomes are heterogeneous: some patients show improvement with immunosuppressive therapy or intravenous immunoglobulin, whereas others experience persistent or progressive dysfunction, especially those with inclusion body myositis. Key prognostic factors include age, disease subtype, autoantibody status, and baseline severity of dysphagia. Dysphagia in IIM should be recognized as a clinically important manifestation associated with both survival and functional outcomes. Early identification and appropriate management are essential to improve patient prognosis. Further prospective studies are needed to establish standardized assessment and risk stratification strategies.

Knee osteoarthritis (OA) is a progressive joint disease associated with pain and disability, and current treatments do not restore damaged articular cartilage. Intra-articular mesenchymal stem/stromal cell (MSC) injection has emerged as a minimally invasive biologic therapy with potential chondroprotective and regenerative effects; however, its capacity for structural cartilage repair remains uncertain. This narrative review summarizes clinical outcomes, with a focus on MRI-based cartilage morphological findings after MSC injection for knee OA. A MEDLINE search through January 30, 2025 identified 53 eligible clinical studies evaluating intra-articular MSC injections for knee cartilage lesions or OA, including 20 studies with MRI-based cartilage assessments. Most studies demonstrated significant improvements in pain and function, with benefits observed within 3-6 months and maintained up to 12-24 months. MSC therapy was safe and well tolerated. MRI findings were heterogeneous: most studies showed no significant structural improvement, while a limited number of studies reported cartilage preservation or modest increases in cartilage thickness. Advanced MRI techniques, including T2 mapping, occasionally detected improvements in cartilage quality. Intra-articular MSC injection provides consistent clinical benefits for knee OA, but current MRI evidence suggests limited and variable morphological cartilage restoration. Further standardized studies are needed to clarify its regenerative potential.