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

Bloodstream infections in pediatric patients

Blood stream infection [BSI] is the leading cause of morbidity and mortality in pediatric patients. This study aims to describe the clinical, microbiological characteristics and outcome of BSI in pediatric patients. We collected the clinical data from all pediatric patients with positive blood cultures. We identified all isolates from these patients from January 2004 to December 2004 at King Khalid University Hospital [KKUH], Riyadh, Saudi Arabia, and determined antimicrobial susceptibilities by MicroScan Walk Away 96 [Dade Behring Inc., West Sacramento, CA95691, USA]. Two hundred and twenty pediatric patients had BSI, of whom 147 [67%] were males and 71 [32.2%] were from intensive care units [ICUs]. Two hundred and ten [95.4%] had single blood culture isolate. One hundred and seventy-three [78.6%] of the isolates were Gram positive bacteria and included the following: Staphylococcus epidermidis [55.4%], Staphylococcus aureus [9.5%] of which 14% were methicillin resistant, Streptococcus pneumoniae [S. pneumoniae] [4.5%], 40% of which were resistant to penicillin and Enterococcus faecalis [4%]. Gram negative bacteria were 44 [20%] and included Escherichia coli and Klebsiella pneumoniae [K.pneumoniae] [3.6% each]. Three isolates [1.3%] were Candida glabrata. None of the Gram positive isolates were vancomycin resistant. Three K. pneumoniae and one Pseudomonas spp. isolates were multiresistant. One hundred and ninety-four [88%] of BSI isolates were hospital acquired. Fever was the most common presentation of pediatric patients [26%] with positive blood culture with no apparent focus of infection. Respiratory tract infections 26 [12%] were the next most common. We seen sepsis in [7.7%] children between 8 days and 6 months of age. Bone and joint infections, cardiac, renal, gastrointestinal diseases, malignancy and surgical cases were other associated clinical diagnoses of BSI in pediatric patients. Patients with immuno- suppressive disorders with BSI had isolates such as Salmonella spp., S. pneumoniae and Pseudomonas spp. Overall mortality was 13 [6%] [p<0.005] and those patients had underlying serious medical conditions with associated risk factors such as prolonged hospital stay, intensive care unit [ICU] admission, indwelling catheterization, mechanical ventilation and prior antimicrobial use. Bloodstream infection is an important cause of morbidity and mortality in pediatric patients. Risk factors for hospital acquired infection include: prematurity, prolonged hospitalization, ICU admission, indwelling catheterization, mechanical ventilation and prior antimicrobial therapy

Enterococcal bacteremia in a teaaching hospital in the central region of Saudi Arabia.

To study enterococcal blood stream infection including the different species isolated, their antibiotic resistance associated risk factors and outcome of treatment. A retrospective and prospective study was carried out over a 12 month period between June 2001 and May 2002 in King Khalid University Hospital, Riyadh, Kingdom of Saudi Arabia. Sixty episodes of enterococcal bacteremia with clinical significance detected in adults and neonates were included. Statistical analysis of the epidemiological characteristic, etiologic risk factors and mortality were determined. Fifty-four [90%] of the episodes were hospital acquired. Fifty-five% of patients were elderly males and 20% were neonates. Patients usually have severe underlying diseases [57%] and the mortality rate was 28%. The estimated duration of hospital stay after acquiring the Enterococcal bacteremia was 40 days. The source of bacteremia remained undetermined in 72% of the episodes. Gastrointestinal tract, urinary tract and intravascular catheter were the most frequently recognized associated sites of infection. Thirty-three patients [55%] had previously received antimicrobial agents [mainly cephalosporins]. In this study, intravascular catheter [p=0.0002], urinary catheter [p=0.00001], mechanical ventilation [p=0.002], previous surgery [digestive tract surgery [p=0.01] and prior stay in an intensive care unit [p=0.03] were the factors associated with Enterococcal bacteremia and mortality. Efforts to reduce the occurrence of enterococcal bacteremia should be focused on appropriate use of cephalosporins and external devices

Isolation of coryneform bacteria from blood cultures of patients at a University Hospital in Saudi Arabia

Coryneform bacteria have been increasingly recognized as opportunistic pathogens in recent years. The aim of this study is to identify and determine the antimicrobial susceptibility of coryneform bacteria isolated from blood cultures of patients seen at King Khalid University Hospital [KKUH], Riyadh, Kingdom of Saudi Arabia and review the literature. All coryneform bacteria isolated from blood culture specimens between January 2001 and March 2003 were prospectively identified by API Coryne System [BioMerieux, France]. Clinical data were collected from each patient's medical record. Antimicrobial susceptibility to 16 antimicrobial agents were determined by minimum inhibitory concentration [MIC] using E-test [AB Biodisk, Solna, Sweden]. Out of 50 coryneform bacteria isolated, 19 different species were identified. Corynebacterium propinquum was the most common species 6/50 [12%] followed by Corynebacterium auris 5/50 [10%], Corynebacterium afermentans, Corynebacterium striatum, Dermabacter hominis, Brevibacterium, and Arthrobacter species 4/50 [8%] each. Underlying chest diseases were common among the patients 11/50 [22%], followed by different surgeries 10/50 [20%]. Of all, 12/50 [24%] patients were from different intensive care units [ICUs], 36/50 [72%] had either vascular, urinary or respiratory intubation. Three patients in ICUs died, one was an elderly patient with gastrointestinal bleeding and 2 teenagers [one had tracheoesophageal fistula and the other was post-arrest road traffic accident patient]. Vancomycin was the most active antimicrobial agent against all coryneform species. The majority had MIC <1 ug/ml. For most isolates, the MIC90s of erythromycin, clindamycin, and ciprofloxacin were above the break points. Corynebacterium striatum was the only isolate susceptible to ampicillin. This study revealed that coryneform bacteria are increasingly being recognized as a cause of serious infections in immunocompromised patients. We recommend identification and susceptibility testing of predominant isolates of coryneform bacteria from different clinical sites of seriously ill patients to select the antimicrobial agent necessary for clinical intervention

Pencillin resistance in serogroups/serotypes of streptococcus pneumoniae causing invasive infections in central Saudi Arabia

To determine the minimum inhibitory concentrations [MICs] of penicillin, ceftriaxone and vancomycin of serogroups/serotypes of Streptococcus pneumoniae [S. pneumoniae] from invasive diseases in all age groups from major hospitals in Riyadh, Kingdom of Saudi Arabia [KSA]. All isolates of S. pneumoniae from patients with invasive pneumococcal infections between February 2000 and November 2001 were prospectively collected from 8 major hospitals in Riyadh, KSA. The isolates were confirmed as S. pneumoniae at the King Khalid University Hospitals, Riyadh, KSA and then serogrouped/serotyped using the agglutination method. The MICs for penicillin, ceftriaxone and vancomycin were carried out using the E-test. Forty-three% of the isolates were resistant to penicillin mostly of the intermediate type [97%]. The resistant strains were mainly confined to serogroups/serotypes 6, 23, 19 and 15 and the 7-valent conjugate vaccine covers 76% of the penicillin-resistant strains. Only one isolate was resistant to ceftriaxone. In view of the rather insignificant level of highly resistant-penicillin strains and the virtual absence of resistance to ceftriaxone we would like to suggest using ceftriaxone for treating invasive pneumococcal infections outside the central nervous system. We recommend that the conjugate vaccine would be a useful adjunct to penicillin prophylaxis in patients at risk in our community

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

Hemophilus influenzae serotype-b meningitis in an adult immunocompetent patient

We present a case of meningitis caused by Hemophilus influenzae type'b in an immunocompetent 41-year-old Saudi lady. The patient was successfully treated with Ceftriaxone for 10 days. A review of Hemophilus influenzae meningitis in adults and the impact of conjugated vaccine on the epidemiology of the disease are given