PubMed Health⌕ Search

Biomedical subjects

I I Raad

Publications and source records attributed to I I Raad.

52 records · Page 3Linked to original sources
PubMed1995

Respiratory syncytial virus pneumonia in hospitalized adult patients with leukemia.

Respiratory syncytial virus (RSV) has been demonstrated to be an important cause of life-threatening pneumonia in adult bone marrow transplant recipients; however, its role in other immunocompromised adults has not been defined. We prospectively studied all adult patients with leukemia who were hospitalized at M. D. Anderson Cancer Center (Houston) during a 1-year period (November 1993 through October 1994). During a 19-week period when RSV was prevalent in the community, it was isolated from 9 (10%) of 87 patients with leukemia who developed an acute respiratory illness. In 6 (75%) of 8 patients with profound chemotherapy-induced myelosuppression, the RSV infection was complicated by pneumonia, with an 83% mortality rate. RSV appears to be an important cause of severe and often fatal pneumonia in myelosuppressed patients with leukemia.

Acute Disease↗
PubMed1994

The relationship between the thrombotic and infectious complications of central venous catheters.

OBJECTIVES: To assess the frequency of thrombotic and infectious complications of long-term use of vascular catheters in cancer patients and to determine whether the two types of complication are related. DESIGN: Case series. SETTING: A 500-bed tertiary cancer center. PATIENTS: Seventy-two cancer patients. INTERVENTIONS: During a 16-month period, postmortem examinations of catheterized veins and contralateral uncatheterized veins were done on all patients with indwelling central venous catheters who met study criteria. MAIN OUTCOME MEASURES: Catheter-related septicemia determined by clinical and microbiological data as well as postmortem pathology; venous pathological changes such as mural hemorrhage, thrombosis, calcification, ulceration, and inflammation. RESULTS: Premortem clinical and microbiological data were obtained retrospectively on all patients. Pathological changes were noted in 35 catheterized veins (49%) compared with five contralateral control veins (9.2%) (P < .001). Mural thrombi were noted in 27 catheterized veins (38%) compared with only one contralateral control vein (1.4%) (P < .001). Other pathological changes consisted of four central venous catheter-related mural thrombi (5.6%) in the right atrium and four instances (5.6%) of nonbacterial thrombotic endocarditis, three involving the tricuspid and one the mitral valves. Seven patients had catheter-related septicemia. Of the 31 patients with mural thrombosis of the catheterized vein or right atrium, seven developed catheter-related septicemia, whereas none of the 41 patients with normal catheterized veins and atria developed catheter-related septicemia (P < .01). CONCLUSIONS: Thrombotic complications are common in catheterized veins and are often associated with catheter sepsis.

Adolescent↗
PubMed1994

Vancomycin penetration into biofilm covering infected prostheses and effect on bacteria.

To evaluate the adequacy of penetration of antibiotics into biofilm, a novel in vitro model for prosthesis-related infection was developed. Sterile stainless steel orthopedic nuts were incubated with slime-producing Staphylococcus epidermidis. Biofilm-covered nuts were exposed to varying concentrations of vancomycin; then biofilms were harvested. Vancomycin levels in biofilm, as measured by fluorescent polarization immunoassay, far exceeded the MIC and MBC of vancomycin for the organism. Bacterial growth in biofilm was inversely related to vancomycin concentration in biofilm, but even extremely high drug concentrations did not eradicate bacteria embedded in biofilm. The MICs and MBCs for bacteria recovered from biofilm did not differ from those for incubating organisms. Thus, failure of glycopeptide antibiotics to cure prosthesis-related infection is not due to poor penetration of drugs into biofilm but likely due to diminished antimicrobial effect on bacteria in the biofilm environment.

Bioprosthesis↗
PubMed1994

The pathogenesis and prevention of central venous catheter-related infections.

Vascular catheters are a major source of nosocomial infections. Definite diagnosis of catheter-related infections should include the use of quantitative catheter cultures or differential quantitative blood cultures. The skin and catheter hub are the two major sources for the introduction of the colonizing organisms. Both microbial (slime) and host (fibrin and fibrinectin) factors contribute to the formation of the biofilm which is essential for the adherence and maintenance of the colonization. Staphylococci and Candida are the leading causative agents. Prolonged duration of catheterization, thrombogenic catheter material, frequent manipulation of the catheter, improper aseptic insertion and maintenance techniques, tranparent plastic dressings, contaminated skin solutions, location of the catheter, and possibly multilumen central venous catheters (CVC) are risk factors predisposing to infections. Preventive measures include a skilled infusion therapy team, topical disinfectants such as chlorhexidine and topical antibiotics, silver impregnated cuffs (for short term CVC), coating catheters with antiseptic agents and maximal barrier precautions during insertion. Exchanging central venous catheters over a guidewire might be useful diagnostically but have not been proven to be of any therapeutic or preventive potential.

Catheterization, Central Venous↗
PubMed1994

Prevention of central venous catheter-related infections by using maximal sterile barrier precautions during insertion.

OBJECTIVE: In many hospitals, the only sterile precautions used during the insertion of a nontunneled central venous catheter are sterile gloves and small sterile drapes. We investigated whether the use of maximal sterile barrier (consisting of mask, cap, sterile gloves, gown, and large drape) would lower the risk of acquiring catheter-related infections. DESIGN: Prospective randomized trial. SETTING: A 500-bed cancer referral center. METHODS: We randomized patients to have their nontunneled central catheter inserted under maximal sterile barrier precautions or control precautions (sterile gloves and small drape only). All patients were followed for 3 months postinsertion or until the catheter was removed, whichever came first. Catheter-related infections were diagnosed by quantitative catheter cultures and/or simultaneous quantitative blood cultures. RESULTS: The 176 patients whose catheters were inserted by using maximal sterile barrier precautions were comparable to the 167 control patients in underlying disease, degree of immuno-suppression, therapeutic interventions, and catheter risk factors for infections (duration and site of catheterization, number of catheter lumen, catheter insertion difficulty, reason for catheter removal). There were a total of four catheter infections in the test group and 12 in the control group (P = 0.03, chi-square test). The catheter-related septicemia rate was 6.3 times higher in the control group (P = 0.06, Fisher's exact test). Most (67%) of the catheter infections in the control group occurred during the first 2 months after insertion, whereas 25% of the catheter infections in the maximal sterile precautions group occurred during the same period (P < 0.01, Fisher's exact test). Cost-benefit analysis showed the use of such precautions to be highly cost-effective. CONCLUSION: Maximal sterile barrier precautions during the insertion of nontunneled catheters reduce the risk of catheter infection. This practice is cost-effective and is consistent with the practice of universal precautions during an invasive procedure.

Adolescent↗
PubMed1992

Quantitative tip culture methods and the diagnosis of central venous catheter-related infections.

The diagnostic usefulness of two quantitative catheter culture methods was compared in a prospective study of central venous arterial catheters. The roll-plate method followed by sonication was used to culture 177 catheters from 85 patients, and the sonication method was used to culture 136 catheters from 68 patients. All patients were evaluated for catheter-related infections. Catheter-related infections were associated with greater than or equal to 100 colony-forming units (CFU) isolated from catheter tips by either roll plate (p = 0.01) or sonication (p less than 0.001). The sensitivity, specificity, and positive and negative predictive values of greater than or equal to 10(3) CFU by roll plate for catheter-related septicemia were 56%, 97%, 63%, and 96% compared with 93%, 95%, 76%, and 99%, respectively, for the same level by sonication. For central venous and arterial catheters, the sonication method can distinguish infection from contamination and is superior to the roll-plate method in that it may offer a more sensitive and predictive alternative in the diagnosis of catheter-related septicemia.

Bacterial Infections↗
PubMed1992

Optimal duration of therapy for catheter-related Staphylococcus aureus bacteremia: a study of 55 cases and review.

Over the last two decades, the optimal duration of therapy for catheter-related Staphylococcus aureus bacteremia has become the subject of controversy. A review of the literature revealed an occasional association between relapse of the infection and a short course of therapy (less than 10 days of iv antibiotic therapy). From records kept between 1983 and 1989 at the University of Florida's affiliated hospitals, we identified 55 patients with catheter-related S. aureus bacteremia. Nine patients (16%) developed acute early complications (e.g., endocarditis or osteomyelitis) while receiving antibiotics. The results of multivariate analysis showed that an early complicated course was characterized by fever and/or bacteremia that persisted for greater than 3 days after catheter removal (P = .02). The remaining 46 patients were followed up for at least 3 months. During follow-up, three of the 18 patients treated for less than 10 days with iv antibiotics developed relapsing septicemia, whereas none of the 28 patients treated for a longer period developed this condition (P = .05). Fever and/or bacteremia that persists for greater than 3 days after catheter removal and initiation of antibiotic therapy suggests an acutely complicated course requiring prolonged treatment. The duration of iv antibiotic therapy in uncomplicated cases should not be less than 10 days but need not be greater than 2 weeks.

Adolescent↗
PubMed1990

Uncontrolled nosocomial rotavirus transmission during a community outbreak.

Between Jan. 11 and March 31, 1983, 60 pediatric patients were diagnosed with rotavirus gastroenteritis. Of these cases 24 were community acquired, 29 were nosocomial, and 7 were of undetermined origin. Despite intensive infection control efforts, nosocomial transmission continued as long as patients with community-acquired cases were admitted. The use of disinfectants and germicides that were ineffective against rotavirus may have contributed to the continued nosocomial spread during a community outbreak.

Communicable Disease Control↗
PubMed1990

Three-year experience with sonicated vascular catheter cultures in a clinical microbiology laboratory.

Using a quantitative sonication method, we cultured 1,681 consecutive vascular catheters submitted to a clinical microbiology laboratory in a 36-month period. A total of 46% of the cultures were positive; the most common organisms isolated were coagulase-negative staphylococci (36.4%), Pseudomonas aeruginosa (13.9%), enterococci (10.0%), yeasts (9.2%), Staphylococcus aureus (5.8%), and Enterobacter species (4.4%). The frequencies of positive blood cultures within 48 h prior to a positive catheter culture result were as follows: Candida albicans (68.4%), S. aureus (60%), Enterobacter cloacae (42.9%), Staphylococcus epidermidis (32.1%), P. aeruginosa (27.7%), and enterococci (23.3%). The sonication method allowed quantification of the number of CFU removed from a catheter for between 10(2) and 10(7) CFU. For catheter cultures in which greater than or equal to 10(2) CFU grew, a linear regression equation could be calculated: (risk of positive blood culture for the same organism) = 14 [log10 (number of organisms removed from the catheter)] -21 (r = 0.93). For catheter cultures in which less than 10(2) CFU grew, positive blood cultures for the same organism were strongly associated with a proven infection at a site distant from the catheter (P = 0.001) or probable contamination (S. epidermidis). Our findings indicate that this technique has considerable potential for use in clinical microbiology laboratories to aid in the diagnosis of vascular catheter infections and for clinical investigations into the pathogenesis of these infections.

Bacteria↗
PubMed1989

The importance of nosocomial transmission of measles in the propagation of a community outbreak.

In late January 1985, a measles outbreak occurred at a community hospital in Columbia county, Florida. The outbreak spread throughout the county and to two neighboring counties (Alachua and Marion), resulting in 79 cases with a 29% hospitalization rate. Hospitals represented the site with the highest frequency of transmission. At the Alachua county hospitals, where strict respiratory isolation measures were taken, no secondary cases occurred among hospitalized patients. Two independent risk factors existed for hospitalization: measles exposure in a hospital setting (P less than 0.05) and nonvaccination (P less than 0.001). Of the total measles cases, 24% were under the age of 16 months and 47% of those aged 16 months or older had a history of appropriate vaccination. Columbia county, which experienced 86% of the cases, had a 5% frequency of unvaccinated students compared to 0.6% frequency at Alachua (P less than 0.001) where only 10% of the cases occurred. This outbreak demonstrates the role of uncontrolled nosocomial transmission of measles in the propagation of a community outbreak.

Cross Infection↗
PubMedDate not supplied

Bacteriologic profile of surgical infection after antibiotic prophylaxis.

Wound infections resulting from contamination during major head and neck surgery continue to be a critical issue. In this study, specimens of pus or draining fluids from the wounds of 43 surgical patients who received perioperative administration of ampicillin/sulbactam or clindamycin were cultured for aerobic and anaerobic isolates to species level. Polymicrobial infections were identified in 13 of 43 patients (30%); 82% of isolates were aerobic organisms (45 of 55), and 18% were anaerobic or facultative species (10 of 55). Nine of 43 patients (21%) showed no bacterial isolates from cultured material. Independent of the primary site of malignancy or antibiotics used, nine of 25 isolates (36%) obtained from patients who underwent concomitant dental extractions, but only one of 24 (4%) who did not, developed anaerobic infections, (p < 0.001). The minimum inhibitory concentration of anaerobic isolates suggested sensitivity to the antibiotics used, and minimum bactericidal concentration data suggested that further postoperative doses may be required to adequately treat the heavily contaminated wounds. These data suggest that wound colonization following dental extraction procedures in clean contaminated head and neck surgery increases the risk of anaerobic infections. The use of a therapeutic dose and longer duration of perioperative antibiotics may be warranted.

Ampicillin↗
PubMedDate not supplied

Acute bacterial sialadenitis: a study of 29 cases and review.

Acute bacterial parotitis (ABP) used to be described as a nosocomial postoperative infection associated with a high mortality. A review of the literature on acute bacterial sialadenitis (ABS) revealed Staphylococcus aureus as the most common pathogen. Between 1970 and 1988, 17 patients with ABP and 12 with acute bacterial submandibular sialadenitis (ABSS) were admitted to a university hospital. Cultures of purulent discharge from the salivary ducts of these patients revealed S. aureus in 53% and viridans streptococci in 31%. During the study period, only six nosocomial cases of ABP occurred out of 289,234 admissions. S. aureus was the organism isolated most frequently in the nosocomial cases. There were no deaths, and all patients recovered following antibiotic treatment without surgical drainage. Advances in antimicrobial therapy and fluid management of hospitalized patients have made nosocomial ABS a rare disease with a favorable prognosis. S. aureus remains the most common pathogen causing ABS even in nosocomially infected patients who are not critically ill.

Adolescent↗
PubMedDate not supplied

Catheter-related infections caused by the Mycobacterium fortuitum complex: 15 cases and review.

Fifteen cancer patients have developed catheter-related infections caused by the Mycobacterium fortuitum complex (M. fortuitum and Mycobacterium chelonae) at M. D. Anderson Cancer Center since 1978. Eleven patients had bacteremia and four had catheter site infections. Nine infections were caused by M. fortuitum and six by M. chelonae. All four bacteremic patients whose catheters were initially removed and who were treated with antibiotics recovered, whereas for all of the seven bacteremic patients whose catheters remained in place, the infection relapsed or treatment failed. Six (86%) of the latter group ultimately responded to additional antibiotic therapy when the catheter was removed. Successful treatment of local catheter infections was accomplished by catheter removal alone or in combination with antibiotic therapy. Fourteen additional cases have been reported, and eight (57%) of these patients also had underlying cancer. Patients with septicemia or an infection at the catheter insertion site responded to catheter removal and appropriate antibiotics. Patients with infection in the catheter tunnel (tunnel infection) responded only after surgical excision of the tissue surrounding the infected tunnel. M. fortuitum complex is a cause of catheter-related bacteremia in patients with cancer. Appropriate treatment consists of antibiotic therapy and catheter removal. Tunnel infections usually also require surgical excision.

Adolescent↗
PubMedDate not supplied

Comparison of cefpimizole with cefotaxime and penicillin G for treatment of uncomplicated gonorrhea.

One hundred sixteen patients (92 men and 24 women) with suspected uncomplicated gonorrhea were randomized in a double-blind manner to receive intramuscular treatment with 1.0 g of cefpimizole, 1.0 g of cefotaxime, or 4.8 x 10(6) units of aqueous procaine penicillin G (APPG) with 1 g of oral probenecid. Seventeen percent were nonassessable (cultures negative, co-existing syphilis, etc.). Infection sites in 96 assessable patients were urethra (78), cervix (17), pharynx (two), and rectum (two). Of 52 patients treated with cefpimizole, 46 (88%) were bacteriologically cured, as compared with 100% (24 of 24) treated with APPG (P = 0.18) and 90% (18 of 20) treated with cefotaxime (P greater than 0.20). On a weight basis the in-vitro activity of cefpimizole against Neisseria gonorrhoeae was similar to that of APPG. Pain at the injection site was reported by 52% of patients treated with cefpimizole as compared with 27% of those given cefotaxime (P = 0.008) and 17% of those given APPG (P = 0.002). No major organ toxicity was found with cefpimizole, cefotaxime, or APPG. Thus, for acute uncomplicated gonorrhea cefpimizole is similar in efficacy to cefotaxime and APPG but has a higher frequency of pain at the injection site.

Adult↗
PubMedDate not supplied

Guidelines for the management of intravascular catheter-related infections.

These guidelines from the Infectious Diseases Society of America (IDSA), the American College of Critical Care Medicine (for the Society of Critical Care Medicine), and the Society for Healthcare Epidemiology of America contain recommendations for the management of adults and children with, and diagnosis of infections related to, peripheral and nontunneled central venous catheters (CVCs), pulmonary artery catheters, tunneled central catheters, and implantable devices. The guidelines, written for clinicians, contain IDSA evidence-based recommendations for assessment of the quality and strength of the data. Recommendations are presented according to the type of catheter, the infecting organism, and the associated complications. Intravascular catheter-related infections are a major cause of morbidity and mortality in the United States. Coagulase-negative staphylococci, Staphylococcus aureus, aerobic gram-negative bacilli, and Candida albicans most commonly cause catheter-related bloodstream infection. Management of catheter-related infection varies according to the type of catheter involved. After appropriate cultures of blood and catheter samples are done, empirical i.v. antimicrobial therapy should be initiated on the basis of clinical clues, the severity of the patient's acute illness, underlying disease, and the potential pathogen(s) involved. In most cases of nontunneled CVC-related bacteremia and fungemia, the CVC should be removed. For management of bacteremia and fungemia from a tunneled catheter or implantable device, such as a port, the decision to remove the catheter or device should be based on the severity of the patient's illness, documentation that the vascular-access device is infected, assessment of the specific pathogen involved, and presence of complications, such as endocarditis, septic thrombosis, tunnel infection, or metastatic seeding. When a catheter-related infection is documented and a specific pathogen is identified, systemic antimicrobial therapy should be narrowed and consideration given for antibiotic lock therapy, if the CVC or implantable device is not removed. These guidelines address the issues related to the management of catheter-related bacteremia and associated complications. Separate guidelines will address specific issues related to the prevention of catheter-related infections. Performance indicators for the management of catheter-related infection are included at the end of the document. Because the pathogenesis of catheter-related infections is complicated, the virulence of the pathogens is variable, and the host factors have not been well defined, there is a notable absence of compelling clinical data to make firm recommendations for an individual patient. Therefore, the recommendations in these guidelines are intended to support, and not replace, good clinical judgment. Also, a section on selected, unresolved clinical issues that require further study and research has been included. There is an urgent need for large, well-designed clinical studies to delineate management strategies more effectively, which will improve clinical outcomes and save precious health care resources.

Anti-Infective Agents↗