Elevated Anti-Mycoplasma pneumoniae IgG Titers in Chronic Epipharyngitis: Insights Into Persistent Immune...

Objective Chronic epipharyngitis is increasingly recognized as a condition that may involve not only local mucosal inflammation but also altered immune responses and diverse systemic symptoms in some patients. This study aimed to investigate the clinical significance of elevated anti-Mycoplasma pneumoniae IgG titers in patients with chronic epipharyngitis and to explore their potential relationship with persistent immune dysregulation and systemic symptoms. Methods This retrospective observational study included 288 patients with chronic epipharyngitis and nine healthy controls. Serum antibodies against Mycoplasma pneumoniae and Mycoplasma fermentans lipid antigens were measured before treatment. Endoscopic inflammatory scores were evaluated longitudinally before and after epipharyngeal abrasive therapy (EAT). Associations between baseline antibody levels and clinical outcomes were analyzed. Results Baseline anti-Mycoplasma pneumoniae IgG levels demonstrated substantial interindividual variability among patients with chronic epipharyngitis. Patients with higher baseline IgG levels exhibited significantly greater improvement in endoscopic inflammatory scores following EAT and showed higher responder rates than those with lower baseline levels. In contrast, antibody levels were not significantly different between patients and healthy controls. These findings suggest that elevated anti-Mycoplasma pneumoniae IgG titers may identify a subgroup of patients with chronic epipharyngitis characterized by enhanced mucosal immune responsiveness and distinct immunological features. Conclusions Elevated anti-Mycoplasma pneumoniae IgG titers may reflect persistent antigenic imprinting and a distinct host immune background rather than active infection in patients with chronic epipharyngitis. The findings provide insight into a potentially distinct immunological subgroup and may contribute to understanding systemic manifestations frequently observed in chronic epipharyngitis, including fatigue, cognitive dysfunction, and autonomic symptoms. Further studies are warranted to clarify the relationship between anti-Mycoplasma pneumoniae immunity, chronic epipharyngeal inflammation, and systemic symptoms.