Biomarkers are not available for monitoring the onset and progression of coronary artery disease (CAD) in patients with obstructive sleep apnea (OSA), a major risk factor for arteriosclerotic cardiovascular diseases. This study aimed to test for correlation between circulating anti-Sorting Nexins 16 antibody (SNX16-Ab) levels, CAD history and clinical parameters of patients with OSA. Sixty-four healthy donors, 82 adults with OSA, and 96 with acute coronary syndrome (ACS) were studied. Serum samples were collected at diagnostic polysomnography in the OSA group or at the disease onset in the ACS group. Serum SNX16-Ab levels were measured by amplified luminescence proximity homogeneous assay (AlphaLISA), and correlation between SNX16-Ab levels and clinical parameters was analyzed. SNX16-Ab levels and apnea-hypopnea index (AHI) were weakly correlated. Additionally, logistic regression analyses of OSA group identified that elevated SNX16-Ab level associated with the history of CAD. Circulating SNX16-Ab could increase during CAD pathogenesis in patients with OSA. Further prospective studies are required to prove the predictive potential of SNX16-Ab level in CAD onset of patients with OSA.

A 67-year-old woman with fever and cough was diagnosed with eosinophilic pneumonia because of eosinophilia and increased eosinophil levels in the bronchoalveolar lavage fluid and transbronchial biopsy lung specimens. However, prednisolone therapy at a previous hospital was ineffective. Histological findings from thoracoscopic lung and lymph node biopsies were consistent with multicentric Castleman's disease (MCD). Since specimens also showed prominent eosinophil and IgG(4)-positive plasma cell infiltration, it was difficult to distinguish IgG(4) related disease (IgG(4)-RD) from MCD. Administration of prednisolone plus tocilizumab improved the symptoms and lung lesions, and prednisolone administration was successfully reduced and then terminated. The present case highlights the difficulty in diagnosing MCD and IgG(4)-RD, and suggests that combined administration of tocilizumab and prednisolone might be effective in such a case.