Abstract
RATIONALE: Inflammation of unknown origin (IUO) in elderly patients is frequently caused by noninfectious inflammatory diseases. When infections and malignancies are ruled out, glucocorticoids (GCs) are often administered as an empirical diagnostic treatment. However, GC carries risks, including osteoporosis and venous thromboembolism (VTE), and in cases of undiagnosed malignancies, GC use may delay definitive diagnosis. Additionally, VTE itself can mimic IUO by inducing inflammation, making diagnosis more complex when multiple conditions coexist. Despite these concerns, comprehensive studies on the risks of empirical GC treatment for IUO are lacking. This case highlights these potential risks. PATIENT CONCERNS: An 84-year-old Japanese woman with no prior medical history presented with a 5-month history of fever and anorexia without identifiable causes. She exhibited persistently elevated C-reactive protein levels, and initial antimicrobial therapy was ineffective. DIAGNOSES: The patient was initially suspected of having noninfectious inflammatory diseases. However, after experiencing complications from GC therapy, further investigations revealed Stage I gastric adenocarcinoma. INTERVENTIONS: Two weeks after hospital admission, prednisolone 30 mg/day was initiated for suspected noninfectious inflammatory diseases, leading to normalization of C-reactive protein. However, upon GC reduction, the inflammatory markers increased again, necessitating continued prednisolone administration. The patient subsequently developed a compression fracture and was later readmitted with right leg edema and pain. Imaging revealed VTE, likely resulting from GC use and immobilization from the fracture. Anticoagulation therapy was initiated, and GC tapering was performed. Despite persistent inflammation, further diagnostic evaluations, including F-fluorodeoxyglucose positron emission tomography/computed tomography, revealed hyperaccumulation in the stomach, leading to endoscopic confirmation of Stage I gastric adenocarcinoma. The patient underwent laparoscopy-assisted distal gastrectomy. OUTCOMES: One year after surgery, no recurrence of malignancy was observed. The patient's inflammatory markers normalized, and no further thromboembolic events were observed. LESSONS: This case demonstrates that GC therapy in elderly IUO patients can lead to severe complications, including VTE, and delayed malignancy diagnosis. Thorough malignancy and thrombus screening should be conducted before GC initiation. Additionally, when VTE occurs in IUO patients, malignancy should be reassessed, even if other risk factors are present. This case underscores the importance of caution when considering empirical GC therapy for IUO.