Coexistence of Sarcoidosis and Sjögren's syndrome with hypercalcemia and renal involvement: A case report and literature review.

BACKGROUND Sarcoidosis and Sjogren's syndrome (SS) are chronic multi-system inflammatory diseases of unknown origin that most commonly attack the salivary glands. Both of the diseases have vague and nonspecific symptoms, causing difficulties for the clinicians to distinguish between the two diseases. Most diagnostic criteria of SS exclude sarcoidosis. However, a coexistence of both diseases should be noted. Here, we reported a case of coexisting sarcoidosis and Sjogren's syndrome, complicated with severe hypercalcemia and renal failure, in addition to a literature review. CASE REPORT A 71-year-old man visited our hospital complaining of daily progressive oral dryness, thirst and blurred vision with a feeling of dry eyes for one-year duration. His physical examination showed enlargement of both sides of cervical and supraclavicular lymph nodes. Lung auscultation showed decreased breath sounds with bibasilar inspiratory crackles. However, initial laboratory results revealed severe hypercalcemia with moderate hypercalciuria and renal failure. The final diagnosis was coexisting SS and sarcoidosis according to clinical, radiological and laboratory data. The patient received oral prednisone therapy for 18 months. After a follow-up of years, the serum calcium concentration, renal function, and chest CT scan remained normal after prednisone treatment stopped for more than 18 months. CONCLUSION In the literature, calcium metabolic disorder and renal involvement have not been reported among patients with Sarcoidosis and Sjogren's syndrome, suggesting that calcium metabolic disorder may be underestimated. Serum and urine calcium concentration should be measured in addition to routine laboratory test.