study of bacterial isolated from corneal specimens and their antibiotic resistance profile

We aim to examine the spectrum of bacteria causing corneal infections and their antibiotic susceptibility patterns. This will serve as a guideline for empiric therapy of corneal infections. We conducted the study over a period of 18 months from March 2001 through December 2002 in King Abdul-Aziz University Hospital, Riyadh, Kingdom of Saudi Arabia. Corneal specimens taken from 200 patients were inoculated directly onto different types of media. The isolates were identified and then tested against the appropriate topical or systemic antibiotics. Sixty-seven [33.5%] of the total specimens were culture positive and 133 [66.5%] were culture negative. Fourteen [7%] of these showed organisms in the Gram stained smears and correlated well with the culture reports. Of the 67 positive cultures, 53 [79.1%] were Gram-positive bacteria mostly coagulase-negative Staphylococci 29 [43.3%] followed by Streptococcus pneumoniae [S. pneumoniae] 13 [19.4%]. Among Gram-negative bacteria 14 [20.9%], Pseudomonas aeruginosa [P. aeruginosa] 10 [14.9%] was the predominant isolate. All the isolates were sensitive to ofloxacin and the commonly used ocular antibiotics. All the isolated bacteria were sensitive to ofloxacin, a fluoroquinolone. Having marked potency for broad-spectrum activity against both Gram-positive and Gram-negative bacteria, make the fluoroquinolones especially the newer generations, a potential single drug therapy for corneal infections

Prevalence of H.influenzae biotypes and their clinical significance in a University Hospital

Hemophilus influenzae is an important pathogen that is responsible for invasive and non-invasive infections in both children and adults. This study aims to assess the relationship of biotypes to the sites of infection, serotypes, antimicrobial susceptibility, b-lactamase production and age. A total of 200 isolates of H.influenzae were obtained from clinical specimens over a period of 12 months from January 2001 through to January 2002 from King Abdul-Aziz University Hospital, Riyadh, Kingdom of Saudi Arabia. Most of the strains were non-typable and were isolated from patients with non-invasive infections. The typable isolates from invasive infections mostly serotype b were isolated from blood, cerebrospinal fluid and hip joint aspirate. Biotype II accounted for 37% of the isolates followed by biotypes III and I [29.5% and 23%]. The remaining 10.5% were made up of biotypes IV, V, VI and VII. A significantly high resistance to cotrimoxazole [33.5%] and ampicillin [19%] was observed. Two point five% of the isolates were resistant to chloramphenicol. All the isolates resistant to ampicillin were b-lactamase producers and susceptible to cefuroxime, ceftriaxone, ciprofloxacin and rifampicin. This study revealed that biotypes II and III are the predominant biotypes of H.influenzae found in non-invasive infections. There is an apparent relationship between biotype and site of infection which could be useful as an epidemiological marker