Multisystem Sarcoidosis Presenting as Severe Hypercalcemic Crisis and Generalized Lymphadenopathy Mimicking Hematological Malignancy: A Case Report.

Sarcoidosis is a multisystem granulomatous disorder of unknown etiology characterized histologically by the formation of non-caseating granulomas in various organs and tissues. Typically, sarcoidosis is recognized by features such as dry cough, fever, erythema nodosum, and bilateral hilar lymphadenopathy. However, when patients present with severe hypercalcemia and generalized lymphadenopathy, sarcoidosis is usually overlooked, and we usually investigate for features of malignancy, bone metastasis, lymphoma, multiple myeloma, and primary hyperparathyroidism. We report the case of a 61-year-old lady who presented with severe hypercalcemia and generalized lymphadenopathy; further investigations ultimately led to the diagnosis of sarcoidosis with multisystem involvement. This case illustrates the importance of considering a broader differential diagnosis in diagnostically challenging cases, especially when typical etiologies are not identified, as early diagnosis and prompt treatment are essential. It also highlights the importance of involving a multidisciplinary team early in the diagnostically challenging cases with multisystem involvement when initial investigations fail to identify more common causes.