Streptococcus pseudopneumoniae as an emerging respiratory tract pathogen at Assiut University hospitals

BACKGROUND AND OBJECTIVES: Streptococcus pseudopneumoniae is a member of viridans streptococci. It is non-capsulated, bile insoluble and optochin susceptible in ambient air but resistant in 5% CO(2). This study aimed to isolate S. pseudopneumoniae from sputum specimens of patients admitted to Chest Department and Chest ICU of Assiut University hospitals, differentiate it from Streptococcus pneumoniae in addition, to evaluate the prevalence of Streptococcus pseudopneumoniae in clinical isolates by phenotypic and genotypic methods, to subject the isolates to antimicrobial susceptibility testing using agar disc diffusion method. MATERIALS AND METHODS: Isolation of Streptococcus pseudopneumoniae from sputum sample and doing phenotypic test (optochin susceptibility test,bile susceptibility test and antimicrobial susceptibility test) and genotypic test by polymerase chain reaction (PCR) for five genes: CpsA, LytA, AliB-like ORF2, 16S rRNA and Spn9802 genes. RESULTS: Twenty isolates of S. pseudopneumoniae were diagnosed phenotypically by optochin susceptibility and bile solubility tests followed by genotypic characterization by polymerase chain reaction (PCR) for five genes: CpsA, LytA, AliB-like ORF2, 16S rRNA and Spn9802 genes. The prevalence of S. pseudopneumoniae among studied patients was 10% (20/200). CONCLUSION: The pure growth of S. pseudopneumoniae from sputum samples together with the great percentage of antibiotic resistance should raise attention to the clinical importance of this organism.