Pneumococcal Infections and Susceptibility Pattern of Streptococcus Pneumoniae to Penicillin and Ceftriaxone and Risk Factors of Acquisition of Infection in Sari Hospitals, 2002-2003

The aim of this study was to investigate the prevalence of pneumococcal infections, to determine penicillin and ceftriaxone susceptibility pattern among Streprococcus pneumoniae and to evaluate the risk factors of acquisition of pneumococcal infections in patients of Sari hospitals.

In this prospective study during one year (2002-2003), all patients admitted with pneumococcal infections in teaching and non-teaching hospitals were included. Diagnosis of pneumococcal infection was performed based on positive microbiological and appropriate clinical and standard laboratory findings. MICs of penicillin and ceftriaxone were determined by Agar dilution method and interpreted by NCCLS methodology. For statistically analysis Chi-square and Fisher's exact tests were used and P<0.05 was defined statistically significant.

Seventy five episodes of pneumococcal infections among 32 pediatric patients and 43 adults were identified. The pattern of Streprococcus pneumoniae infections were similar between children and adults, and the most common infections were pneumonia (65.3%) and bacteremia (24%). The rate of penicillin and ceftriaxone nonsusceptible Streprococcus pneumoniae isolated from pediatric patients was higher than that in adult patients (93.8% versus 53.4%, P<0.01). This finding was correlated to prior penicillin use that was more common in children (37.5%) than in adults (7%). P=0,001. The susceptibility pattern of Streprococcus pneumoniae to penicillin and ceftriaxone isolated form pediatric patients and adults was different (6.2% from children, 46.6% in adults, P=0.0009). Eighty four percent of adults and 6.2% of pediatric patients had major underlying diseases (P<0.0001). This findings explain why adult patients tended to run higher mortality (30.2%) than children (6.8%).

This survey emphasis on vaccination of young children and elderly with major underlying diseases to prevent pneumococcal infections.