Biomedical subjects

Issam Raad

Publications and source records attributed to Issam Raad.

41 records · Page 3Linked to original sources

PubMed2002

Failure of oral antimicrobial agents in eradicating gastrointestinal colonization with vancomycin-resistant enterococci.

Eradication of gastrointestinal colonization with vancomycin-resistant enterococci (VRE) using a combination of oral bacitracin and gentamicin was evaluated. Twenty-eight evaluable treated patients were matched with 28 control patients. After 3 months of follow-up, 5 patients (18%) in the treatment group versus 1 patient (4%) in the control group (P = .2) had negative results on stool cultures, with a similar frequency of VRE bacteremia (P = .8). The use of oral bacitracin plus gentamicin did not reduce VRE colonization or bacteremia.

Administration, Oral↗

PubMed2002

Risk factors for vancomycin-resistant Enterococcus (VRE) infection in colonized patients with cancer.

To determine the risk factors for vancomycin-resistant Enterococcus (VRE) infection in colonized patients with cancer, we conducted a case-control study. According to multivariate analysis, the only significant factors were neutropenia (< 500 cells/mm3) for more than 1 week and the use of oral vancomycin. Therefore, colonized neutropenic patients with cancer who have previously used oral vancomycin are most prone to VRE infection.

Adolescent↗

PubMed2002

Epidemiology, molecular mycology, and environmental sources of Fusarium infection in patients with cancer.

OBJECTIVE: To investigate the epidemiology and environmental sources of Fusarium infections in patients with cancer. DESIGN: Retrospective case-control study conducted following surveillance environmental cultures and DNA analysis of isolated organisms. SETTING: A tertiary-care, university cancer center. METHODS: In 1996 and 1997, environmental cultures were performed on air samples and water systems. A retrospective chart review was performed for 70 patients with cancer identified with fusariosis between 1987 and 1997. Patients with fusariosis were compared with 49 uninfected control patients who occupied hospital rooms with positive environmental cultures for Fusarium. With the use of random amplification of polymorphic DNA, organisms isolated from infected patients were compared with environmental organisms. RESULTS: Most of the patients with Fusarium (40, 57%) were infected on or within 3 days of admission, indicating community rather than nosocomial acquisition. Patients were comparable in terms of underlying immunocompromised status to 49 uninfected control patients. However, the duration from admission to infection in the patients with fusariosis tended to be shorter than the duration from admission to discharge in the exposed control patients (P = .06). Water cultured from the hospital tanks and from sinks and water fountains was negative for Fusarium. With the use of polymerase chain reaction, environmental isolates did not match clinical ones. Quantitative air sampling showed that the quantitative outdoor Fusarium levels were eightfold higher than the indoor levels. During the rainy summer season, outdoor air concentrations of Fusarium were at their highest, coinciding with the peak incidence of fusariosis at our center. CONCLUSION: The most likely source of fusariosis was the external environment rather than nosocomial sources, such as water.

Adolescent↗

PubMed2002

Efficacy of minocycline and EDTA lock solution in preventing catheter-related bacteremia, septic phlebitis, and endocarditis in rabbits.

To determine the efficacy of antibiotic catheter lock solution in preventing catheter-related infections, silicone catheters were tunneled and inserted into the jugular veins of 18 rabbits. The catheters were challenged with an intraluminal injection of 10(5) CFU of slime-producing Staphylococcus epidermidis in 0.1 ml of water. The catheters were maintained on heparin (100 IU/ml) flush for the first 3 days. On day 3, quantitative blood samples for culture were obtained from the catheters and ear veins, which documented catheter-related bacteremia, and the rabbits were randomized to have their catheters flushed as follows: five animals were continued on heparin (100 IU/ml), five animals received vancomycin (3 mg/ml) with heparin (100 IU/ml), and eight animals received 3 mg of minocycline per ml with 30 mg of EDTA per ml (M-EDTA). All animals were killed at day 7. Blood, catheters, jugular veins, and heart valves were cultured quantitatively. Animals maintained on heparin developed catheter-related colonization, bacteremia, septic phlebitis, and endocarditis. Vancomycin-heparin partially prevented catheter colonization, bacteremia, and phlebitis (P = 0.2). M-EDTA completely prevented catheter colonization, catheter-related bacteremia, and phlebitis in all of the animals (P < 0.01). Tricuspid endocarditis was equally prevented by vancomycin-heparin and M-EDTA (P < or = 0.06). In conclusion, the M-EDTA catheter flush solution was highly efficacious in preventing catheter-related colonization, bacteremia, septic phlebitis, and endocarditis in rabbits.

Animals↗

PubMed2002

Diagnosis of invasive pulmonary aspergillosis using polymerase chain reaction-based detection of aspergillus in BAL.

STUDY OBJECTIVE: To assess the value of Aspergillus polymerase chain reaction (PCR) test performed on the BAL in diagnosing invasive pulmonary aspergillosis (IPA). DESIGN: Between January 1996 and 1997, we prospectively followed up 249 cancer patients with pulmonary infiltrates suggestive of pneumonia. Bronchoscopy with fungal stains, cultures, and PCR was performed on all patients. PCR was used for the detection of Aspergillus mitochondrial and alkaline protease gene DNA. The PCR products were visualized either directly on polyacrylamide gel or after Southern transfer and probing with specific probes for mitochondrial and alkaline protease DNA. RESULTS: The 249 patients consisted of 10 patients with proven IPA (tissue invasion), 22 patients with probable IPA (microbiologic culture), 18 patients with possible IPA (consistent clinical and radiologic findings), and 199 control patients with no evidence of IPA. PCR positivity was strongly associated with all forms of IPA (p < 0.002). The sensitivity, specificity, positive predictive value, and negative predictive value of PCR were 80%, 93%, 38%, and 99%, respectively, for proven IPA, and 64%, 93%, 52%, and 96%, respectively, for probable IPA. Southern blotting analysis did not improve the diagnostic yield of the PCR test. CONCLUSION: PCR performed on BAL is associated with high specificity and negative predictive value for IPA. The low positive predictive value could be related to the transient colonizing presence of aspergilli in the respiratory tract. The sensitivity correlates with the certainty of the diagnosis based on tissue invasion.

Adolescent↗