title: Detection of pneumococci with increased resistance to penicillin and their clinical significance.
abstract: Streptococcus pneumoniae isolates from blood, CSF, respiratory tract and other clinical specimens from 626 patients were tested for sensitivity to penicillin. The bacteria were collected from patients in different hospitals in Riyadh, Saudi Arabia. Using 1 microg oxacillin disk, 147 (23.5%) of these isolates were found to be relatively resistant to penicillin (RPR). When 358 pneumococcal isolates were tested for RPR using 1 or 10 unit penicillin disks and compared with the MIC or oxacillin disk, as many as 18% were incorrectly designated as sensitive meningitis, septicemia and pneumonia, the significance of determining their correct susceptibility to penicillin cannot be over emphasized.
authors.affiliation: Departments of Pediatrics and Pathology and Laboratory Medicine, King Faisal Specialist Hospital and Research Centre, Riyadh, and Department of Pharmacy, King Saud University, Riyadh, Saudi Arabia.
authors.forename: F
authors.initials: F
authors.lastname: Al-Zamil
authors.forename: A
authors.initials: A
authors.lastname: Shibl
authors.forename: S M
authors.initials: SM
authors.lastname: Qadri