Evaluation of Diagnostic and Prognostic Accuracy of Serum C-Reactive Protein and Blood Cultures from Acute Infective Endocarditis Patients

Abstract

Risk identification and early diagnosis in infective endocarditis patients are considered limited approaches due to their poor microbiological outcomes and slow diagnostic accuracy. To reduce these risks, a rapid identification marker is needed. The current study was designed with the objective of assessing C-Reactive Protein (CRP) efficiency as a means of evaluating the diagnosis of infective endocarditis and its prognostic ability, as well in comparison with blood cultures. CRP was performed using a sandwich-based enzyme-linked immunosorbent assay (ELISA), while the blood cultures were performed using a bacterial culture technique. Antibiotic susceptibility testing was performed to ascertain potential antibiotics to treat infective endocarditis. A total of 1789 patients with suspected endocarditis were recruited, of whom 381 were diagnosed as having infective endocarditis. All the serum samples were tested for CRP, and the blood samples were processed for blood cultures. CRP with less than 1.0 mg/dl was considered negative. Out of 1627 patients, a total of 381 had a positive or higher CRP serum level. The blood culture of 139 patients was positive, with Staphylococcus aureus being the most predominant (n = 46) pathogen. Hospital death was seen in 23 patients with a significantly high CRP level. During treatment, the responsive interventions showed a 20% decrease in disease severity; however, at the end of the treatment, after eradication of symptoms, CRP level varied in 59 patients. The current study concluded that CRP after the first week of treatment is a significant predictor of clinical outcome and can be used as a good prognostic marker.