Clinical associations of incidentally detected parotid gland calcification on CT.

OBJECTIVES/HYPOTHESIS Parotid gland calcifications can be incidental findings on computed tomography (CT) and have been reported to be associated with chronic inflammatory conditions. Associations between parotid gland calcification and other common medical conditions have not been reported. METHODS Following institutional review board approval, 1,571 patients who underwent noncontrast head CT with 1.25-mm slice thickness on a 64-detector row CT between January 2011 and July 2011 were retrospectively reviewed for parotid gland calcifications. Medical records were reviewed for chronic kidney disease, alcoholism, autoimmune conditions, endocrine disorders, elevated alkaline phosphatase, and HIV (human immunodeficiency virus) status. Statistical analyses were performed using Fisher's exact test and multiple logistic regression. RESULTS Sixty-three of 1,571 (4%) patients had parotid gland calcifications. Significant associations were observed between parotid gland calcifications and HIV infection (P = 0.002), chronic kidney disease (P < 0.0001), alcoholism (P < 0.0001), elevated alkaline phosphatase (P = 0.003), and autoimmune disease (P = 0.02). CONCLUSION Parotid gland calcifications were associated with HIV, alcoholism, chronic kidney disease, autoimmune disease, and elevated alkaline phosphatase. LEVEL OF EVIDENCE 4.