['There is insufficient data regarding the differential diagnosis and the prognostic value of significantly elevated serum levels of C-reactive protein (CRP) in hospitalized medical patients.', "A retrospective review of medical charts of patients admitted to a tertiary hospital's Internal Medicine ward during a period of 1 year who had at least one CRP serum level measurement of 200mg/L or more.", 'Overall, 341 patients with a mean age of 69.8+/-1.0 years were included in the study. Acute infection was the most prevalent diagnosis (n=293; 85.9%) with community-acquired pneumonia being the most common acute infection (n=115; 33.7%). Non-infectious conditions accounted for 9.1% (n=31) of the diagnoses and included mainly malignant metastatic diseases (n=19; 5.6%). Overall, 70 (20.5%) patients died within 30 days of admission. Age and active malignancy, with metastasis or without metastasis, were independently associated with 30-day mortality.'] Are significantly elevated C-reactive protein serum levels associated with very high 30-day mortality rates in hospitalized medical patients?