Clinical Characteristics of Pneumococcal Infections and Predictors of Invasive Pneumococcal Disease

Objectives: Streptococcus pneumoniae infections are an important cause of morbidity and mortality, especially among high-risk groups. Our country has limited data on the clinical findings of pneumococcal infections and invasive pneumococcal disease (IPD). Therefore, we aimed to evaluate patients’ demographic and clinical findings with pneumococcal infection. Methods: The data of the patients who were admitted to our hospital between January 2012 and December 2016 were analyzed retrospectively. Isolation of Streptococcus pneumoniae from sterile body sites was defined as invasive pneumococcal disease. Demographic data, clinical findings, laboratory values, and death rates of patients with the pneumococcal disease were analyzed statistically. Results: One hundred and fifty-four patients were included in the study. Of these patients, 106 (68.8%) were male, and the mean age was 65.3±15.6 (20-94). The diagnosis of the patients were pneumonia (79.2%), sepsis (10.4%), wound infection (3.2%), peritonitis (1.9%), epididymoorchitis (3.2%), pyelonephritis (3.2%), meningitis (1.3%), brain abscess (0.6%), arthritis (0.6%), endocarditis (0.6%) and pericarditis (0.6%). The mean follow-up period was 27.8±22.3 months. The overall mortality rate was 32.5% in all patients. Invasive pneumococcal disease was detected in 31 (20.1%) of all patients. C-reactive protein (CRP) levels (>14.4 mg/dL), penicillin and ciprofloxacin sensitivity rates were significant parameters in invasive pneumococcal disease patients (p=0.039, p=0.028 and p=0.045). Pneumococcal strains obtained from patients with IPD were more susceptible to penicillin and ciprofloxacin than non-invasive pneumococcal strains (96.4% and 78.8%, p=0.028; 100%, and 42.9%, p=0.045). Conclusion: Knowledge of risk factors associated with pneumococcal infections in our country is crucial in supporting national immunization programs. CRP elevation, penicillin sensitivity, and fluoroquinolone sensitivity rates were significantly higher in patients with IPD. According to the results of our study, immunocompromised patients and patients with comorbidities have a higher risk for the development of invasive disease. Keywords: invasive, pneumococcus, risk factors, Streptococcus pneumonia