This report presents the case of a 71-year-old Chinese female with atypical symptoms leading to the diagnosis of metastatic caecal adenocarcinoma with overlapping connective tissue disease, initially identified as possible paraneoplastic dermatomyositis. The patient, with no significant medical history, was referred for elevated serum creatine kinase (CK) levels and exhibited progressive lethargy, upper limb weakness, and notable weight loss over three months. Clinical examination revealed violaceous rashes and significant muscle weakness, prompting a provisional diagnosis of dermatomyositis. However, extensive investigations, including computed tomography (CT) imaging and colonoscopy, uncovered metastatic disease characterized by peritoneal collections and a caecal tumor. The autoimmune panel indicated elevated anti-ribonucleoprotein (anti-RNP), anti-Sjögren's Syndrome A/Ro (anti-SSA/Ro), anti-topoisomerase I (anti-Scl-70), and anti-Ku antibodies, while key cancer-associated myositis markers were absent. This scenario highlights the complex interplay between malignancy and autoimmunity, emphasizing the necessity for a multidisciplinary approach in diagnostic evaluation. The findings advocate for heightened awareness of malignancy in older adults presenting with inflammatory myopathy, as timely diagnosis and intervention are critical in reducing morbidity and mortality associated with malignancies.

We present the case of a 48-year-old female with a complex medical history, including chronic joint pain on methadone and chronic obstructive pulmonary disease (COPD), who developed right forearm myositis following a series of orthopedic procedures and infections. Initially thought to be infectious in origin, subsequent investigations revealed chronic inflammation without infection. The patient's serologic profile evolved over time, with new-onset SSA antibody positivity, positive antinuclear antibody (ANA) and rheumatoid factor (RF), and concern for overlapping connective tissue disease. This case highlights the diagnostic complexity and evolving nature of autoimmune conditions, particularly in patients with non-specific musculoskeletal symptoms and comorbidities.

Polymyositis with concomitant scleroderma is a rare, progressive condition with profound consequences if not addressed promptly. Severity and symptom presentation varies between patients, and much is unknown about how best to treat overlapping connective tissue diseases. This case discusses the rare presentation, medical evaluation, and successful treatment of a 46-year-old woman with excessive muscle atrophy, weakness, and tissue fibrosis, who was diagnosed with overlapping connective tissue disorder after extensive work up that included a muscle biopsy, skin punch biopsy, and autoantibody lab work. This patient recovered well with the use of mycophenolate mofetil demonstrating promising results for similar patients and offering insight into potential methods of evaluation and medical management. Studying cases like this one give providers more knowledge about overlapping connective tissue disease and how to best diagnose and manage them.

A 63-year-old woman with diabetes presented with 8 weeks of proximal muscle weakness and change in bowel habits. Muscle biopsy confirmed myositis, and serological studies were consistent with dermatomyositis (DM), without evidence of overlapping connective tissue disease or malignancy. On day 12 of prednisone therapy and after receiving one dose of IVIG with improvement in muscle strength, the patient developed abdominal pain and was diagnosed with a gastrointestinal (GI) perforation and peritonitis requiring emergent colectomy. The pathology revealed diffuse mucosal ulceration, prominent lymphoplasmacytic infiltration, venous occlusion and arterial hyperplasia. Although GI manifestations due to GI vasculopathy are rare in adult DM and are often a delayed complication, in this patient, it was one of the initial manifestations of this condition. In addition to being a fatal complication, clinicians should be aware of these complications, as immunosuppression used to control the muscular and cutaneous inflammation may not control the GI vasculopathy.

To determine the clinical and pathological characteristics of eosinophilic gastrointestinal disease (EGID) associated with autoimmune connective tissue disease (CTD). Systematic literature review. Twenty cases of CTD associated with EGID were identified. Systemic lupus erythematosus was the main EGID-associated CTD (35%), followed by rheumatoid arthritis (20%), systemic sclerosis or inflammatory myopathies (15%, each), and Sjögren's syndrome, scleromyositis or other overlapping connective tissue disease (5%, each). No patient had a history of atopy. In contrast with classical EGID among which eosinophilic esophagitis is the most frequent type, eosinophilic gastritis and/or enteritis represented 95% of cases. Gastrointestinal symptoms were often unspecific. Peripheral eosinophilia was found in 67% of cases. Upper and lower gastrointestinal endoscopy showed abnormal findings in only 40% and 30% of cases, respectively. EGID was confirmed by evidence of digestive eosinophilic infiltration, mainly in mucosal or submucosal layer. In all but one patient, the CTD was diagnosed prior to the occurrence of the EGID. In total, 95% of EGID had a favorable outcome, with corticosteroids being used in almost all cases. Clinicians should consider EGID as a possible diagnosis and perform gastrointestinal tract biopsies in patients with CTD presenting with gastrointestinal symptoms and unexplained eosinophilia. Conversely, more rarely extra-digestive features during follow-up in patients with EGID may lead to a diagnosis of an associated CTD. More research is needed to better understand the underlying pathophysiological processes leading to eosinophilic gastrointestinal infiltration in patients with CTD.