Irritable bowel syndrome with diarrhea (IBS-D) is a prevalent functional gastrointestinal disorder. Emerging evidence suggests that chronic low-grade inflammation is a significant pathophysiological mechanism, playing a pivotal role in disrupting intestinal homeostasis and driving disease pathogenesis in a subset of patients. Key contributing factors include intestinal immune dysregulation, gut microbiota imbalance, prior infections, and brain-gut axis dysfunction. Within this complex interplay of physiological and pathological processes, the core mechanisms involve abnormal immune cell activation, release of inflammatory mediators, and engagement of key inflammatory signaling pathways. Although current IBS-D management remains largely symptomatic, with no curative approaches available, the growing insight into low-grade inflammatory mechanisms offers new therapeutic prospects. Targeting intestinal low-grade inflammation is emerging as a highly attractive direction for creating novel treatment strategies. Further research is necessary to identify effective inhibitors of low-grade inflammation in IBS-D and to assess whether treatment aimed at this inflammation can prevent or alleviate the development and progression of the disease.

Intraspinal foreign body retention is a rare clinical entity, usually resulting from trauma, surgery, or invasive procedures, and may lead to progressive neurological dysfunction. We report a patient who presented with burning pain in the right sole and bilateral lower limb weakness, and was diagnosed with a retained metallic foreign body in the thoracic spinal canal by imaging examinations. We discuss the clinical features, imaging diagnosis, and surgical management based on the diagnostic and therapeutic process of this case. This report indicates that invasive therapies such as acupuncture carry the potential risk of needle breakage, migration, and subsequent intraspinal foreign body retention, which deserves clinical attention. Strict standard operation during acupuncture is crucial to avoid such iatrogenic complications.