CRP and syphilis: Upon admission, the patient had undergone the following diagnostic tests: complete blood count (CBC); liver function tests (LFTs); procalcitonin (PCT); C-reactive protein (CRP); viral serology for hepatitis B, hepatitis C, HIV, and syphilis; amylase; lipase; creatinine kinase (CK); bilirubin; albumin; creatinine; estimated glomerular filtration rate (eGFR); blood urea nitrogen (BUN); urinalysis; urine culture; blood cultures (for both aerobes and anaerobes); and stool cultures.