Differences in the effectiveness of serum biomarkers for the diagnosis of bacterial infections in adult and elderly patients admitted to the emergency department

Background/aim: This study aimed to evaluate the superiority of procalcitonin (PCT), C-reactive protein (CRP) levels, white blood cell (WBC) counts, and erythrocyte sedimentation rate (ESR) in discriminating among infection, systemic inflammatory response syndrome (SIRS), and sepsis, and their differences according to age groups. Materials and methods: The patients were divided into an adult group and a geriatric group (over 65 years) and classified according to the presence of infection, SIRS, and sepsis. The patients' laboratory values (PCT, CRP, WBC, ESR), demographic characteristics, and vital signs were taken into consideration. Results: When the laboratory parameters were evaluated, there were no significant differences in the PCT, WBC, and ESR values between the age groups (P > 0.05). CRP was significantly higher in the adult patient group compared to the geriatric group (P < 0.001). When the two groups were compared in terms of infection, there were no significant differences in the PCT levels and the WBC count (P > 0.05) in SIRS and sepsis. In addition, the CRP levels and the ESR were significantly higher in the adult sepsis patients when compared with the geriatric patients (P < 0.001). Conclusion: PCT levels do not distinguish among infection, SIRS, and sepsis in adult and geriatric age groups.