PubMed Health⌕ Search

Biomedical subjects

S Ashkenazi

Publications and source records attributed to S Ashkenazi.

At least 19 recordsLinked to original sources

Hepatitis A virus seropositivity among hospital and community healthcare workers in Israel-the role of occupation, demography and socioeconomic background.

Hospital and community-clinic workers were tested for hepatitis A virus antibodies (HAV)-IgG to identify variables associated with presence of (HAV-IgG) and to determine whether sociodemographic background may explain all differences in HAV seropositivty among healthcare workers. Logistic regression analysis was used to identify variable associated with HAV-immunity. Multivariate logistic regression analysis revealed that HAV-seroprevalence correlated significantly (P<0.01) with age, siblings, residence in rural areas and origin. Nurse aides had an increased risk for HAV seropositivity (OR=5.04; 95% CI: 1.49-17.08) whereas physicians had a lower risk (OR=0.54: 95% CI: 0.30-0.98). Age and socioeconomic background were independently correlated with HAV immunity but did not explain all difference in HAV-seroprevalence. The higher susceptibility and elevated incidence of hepatitis A amongst physicians, prioritize primary prevention in this group.

Academic Medical Centers↗

Nosocomial infections after cardiac surgery in infants and children: incidence and risk factors.

This prospective study was undertaken to determine the spectrum, sites and main risk factors for hospital-acquired infections (HAI) in our paediatric cardiothoracic intensive care unit (PCICU), and to determine the main organisms causing bloodstream infection in this setting. All patients admitted between January and December 1999 were prospectively followed for the development of HAI. To define risk factors, patients were grouped by age, complexity score, length of stay in PCICU, and whether the patient's chest was open or closed postoperatively. Three hundred and thirty-five patients underwent cardiac surgery. Fifty-five patients acquired 69 HAIs (HAI patient rate 16.4%). The most common HAI were bloodstream and surgical wound infection in 10 and 8%, respectively. The main causative organisms were Klebsiella spp.,Enterobacter spp. and Pseudomonas spp. in 22, 17 and 16% of episodes, respectively. Staphylococcus spp. accounted for 16% of episodes. The main risk factors for developing HAI were: neonatal age [P < 0.05, odds ratio (OR): 5.89, 95% confidence interval (CI): 2.96-11.58] prolonged PCICU stay (P < 0.05, OR: 6.82, 95% CI: 3.37-14.48), open chest postoperatively (P < 0.05, OR: 3.44, 95% CI: 1.31-8.52) and high complexity score (P < 0.05, OR: 4.03 95% CI: 1.87-8.43). The main causative organisms of bloodstream infections in children hospitalized in the PCICU differ from those in adult and pediatric general intensive care units (ICUs) and include mainly Gram-negative bacilli. High complexity score, neonatal age, prolonged ICU stay, and open chest postoperatively are risk factors of HAI in this patient population.

Catheterization, Central Venous↗

Retrospective analysis of the first clonal outbreak of nalidixic acid-resistant Shigella sonnei shigellosis in Israel.

Reported here is a retrospective molecular analysis of the isolates recovered from the first outbreak of nalidixic acid (NA)-resistant Shigella sonnei shigellosis to occur in Israel. The outbreak affected 94 children. In the retrospective analysis, a total of 13 NA-resistant isolates and five NA-susceptible isolates recovered during the outbreak period were examined. Restriction fragment length polymorphism profiles obtained by digestion with BamHI, PvuI, HinfI or SmaI yielded identical profiles for all 18 isolates. All NA-resistant strains had an identical plasmid profile, but this profile differed from that displayed by the susceptible strains. In all of the NA-resistant strains a 304 bp fragment in the gyrA gene coding for a region associated with NA resistance was sequenced and showed a single point mutation, Ser83-->Phe. In this outbreak, the isolates of NA-resistant Shigella sonnei belonged to a single clone and NA resistance was associated with a point mutation in the gyrA gene.

Adolescent↗

Changing distribution of Candida species isolated from sterile and nonsterile sites in Israel.

To determine if the prevalence of non- albicans Candida spp. has increased at two institutions in Israel, the distribution of 6,954 Candida isolates obtained from sterile and nonsterile sites during the periods 1995-1996 and 1999-2000 were compared. In the latter period, a slight decrease was observed in the prevalence of non- albicans Candida spp. isolated from sterile sites (from 39% to 37%) and nonsterile sites (from 38% to 35%). Specifically, the prevalence of Candida glabrata increased significantly in sterile sites, from 26% to 35% (P=0.0095), and in nonsterile sites, from 18% to 27% (P<0.0001), and the prevalence of Candida krusei increased significantly in sterile sites, from 2% to 7% (P=0.0072). The prevalence of Candida parapsilosis decreased significantly in nonsterile sites, from 31% to 23% (P=0.0002). Continuous surveys of the distribution of Candida spp. and analysis of the clinical significance of changes are warranted.

Candida↗

Hepatitis B vaccination: long-term follow-up of the immune response of preterm infants and comparison of two vaccination protocols.

BACKGROUND: We conducted a 3-year follow-up study of long-term antibody persistence following vaccination of low-risk preterm infants with recombinant hepatitis B vaccine (HBV). Two three-dose protocols were compared: vaccination beginning within 24 h of birth to initial vaccination delayed until a weight of 2,000 g was reached. SUBJECTS AND METHODS: The study population included 136 children, divided into three groups: children born prematurely (< or = 35 weeks, n = 57), children born at term (> or = 37 weeks, n = 39), both groups receiving the first dose of HBV within 24 h of birth, and children born prematurely (< or = 35 weeks, n = 40), who received the first dose of HBV when a weight of 2,000 g was reached. All infants received the second hepatitis vaccination 1 month after the first, and the third dose 6 months after the first. Hepatitis B surface antibody (AntiHBs) was measured at an age of 3-3.5 years (at least 2.5 years after completion of the three-dose HBV series). An AntiHBs level of > or = 10 IU/l was considered positive. RESULTS: At 3-3.5 years of age, a higher percentage of the premature-delayed vaccination group had a positive AntiHBs level (92.5%) compared to both the premature (54.4%, p < 0.001) and full-term groups (71.8%, p < 0.05) vaccinated soon after birth. The premature-delayed vaccination group also had a significantly higher geometric mean concentration (GMC) (119 vs 14.2 IU/l, p < 0.001 and 119 vs 32.7 IU/l, p < 0.005, respectively). CONCLUSION: Delaying vaccination of premature infants against hepatitis B until a weight of 2,000 g was reached resulted in both a significantly higher percentage of children with positive antibody levels and a significantly higher GMC at 3-3.5 years of age as compared to early-vaccinated preterm and full-term infants. The known short-term advantage of delayed vaccination of preterm infants was shown to persist for at least the first 3 years of life.

Age Factors↗

Long-term outcome of infective endocarditis: the impact of early surgical intervention.

To determine the impact of early surgical intervention on long-term survival in patients with infective endocarditis (IE), charts of all patients who had IE from January 1987 through December 1996 were reviewed. A total of 252 patients with definite or possible IE were included. Forty-four patients (17.5%) had early surgery on median hospital day 2 (range, 0-30 days), and 208 patients (82.5%) received medical treatment alone. On multivariate analysis, several variables, including early surgical intervention, improved long-term survival rates (hazard ratio, 1.5; P=.03), mainly in patients with Staphylococcus aureus etiology (P=.04). When patients with prosthetic devices were excluded, the median duration of survival for patients who had early surgery was >150 months, compared with 61.5 months for patients in the medical group (P=.1). Early surgical intervention compared with medical therapy alone is associated with increased short- and long-term survival rates in patients with IE, primarily when IE is caused by S. aureus.

Adolescent↗

Early responses to nonconjugated polyribosylribitol phosphate challenge as evidence of immune memory after combined diphtheria-tetanus-pertussis-polio-Haemophilus influenzae type b primary vaccination.

OBJECTIVES: A high risk of invasive Haemophilus influenzae type b (Hib) disease exists in the first few years of life. A reduction in anti-polyribosylribitol phosphate (PRP) antibody concentrations follows the administration of certain diphtheria-tetanus-acellular pertussis (DTPa)-based Hib conjugate combined vaccines. However, these combined vaccines prime the immune memory, which is an important factor in protection. As yet there is no direct evidence of the time scale involved in the development of the immune memory post-primary vaccination. In this report we investigated the presence of immune memory at 10 and 12 months of age, 4 and 6 months after primary vaccination of young infants with a pentavalent combination of DTPa, inactivated poliovirus vaccine (IPV) and Hib (DTPa-IPV/Hib) vaccine. METHODS: In two trials (A and B) infants received DTPa-IPV combined with Hib-tetanus conjugate (PRP-T) vaccine at 2, 4 and 6 months of age. The presence of immune memory was assessed by measuring anti-PRP concentrations 7 to 10 days after a nonconjugated PRP challenge given at 10 months in Trial A and at 12 months in Trial B. RESULTS: Administration of a nonconjugated PRP challenge 4 and 6 months after primary vaccination in Trials A and B, respectively, elicited an increase in anti-PRP geometric mean concentrations (4.5 and 5.8 microg/ml, respectively) within 7 to 10 days. These concentrations exceed those reported in the literature involving unprimed children who had received a single dose of nonconjugated PRP at the same age. CONCLUSION: The results demonstrate the development of anti-PRP immune memory at an early age, 4 and 6 months after completion of a three dose primary vaccination course of combined DTPa-IPV/Hib vaccine. The ability of primed infants to mount a rapid response is an important observation given the high risk of Hib infection at this critical age.

Antibodies, Bacterial↗

Mycetoma of the renal pelvis caused by Fusarium species.

A preterm infant, with posterior urethral valves had a mycetoma of the renal pelvis caused by Fusarium species. Prolonged treatment with amphotericin B alone or with flucytosine failed. Combined surgical drainage and medical therapy resulted in full resolution.

Adult↗

Emergence of multiple human cytomegalovirus ganciclovir-resistant mutants with deletions and substitutions within the UL97 gene in a patient with severe combined immunodeficiency.

Infection with multiple ganciclovir-resistant human cytomegalovirus mutants, containing different substitutions and deletions in the UL97 gene, was found in a patient with severe combined immunodeficiency (SCID) within 3 weeks of ganciclovir therapy. A novel 11-codon deletion at positions 590 to 600 was identified. These unique findings may be related to the nature of the immunodeficiency in the SCID patient.

Amino Acid Substitution↗

Safety and immunogenicity of improved Shigella O-specific polysaccharide-protein conjugate vaccines in adults in Israel.

Data suggest that the O-specific polysaccharide (O-SP) domain of the lipopolysaccharide (LPS) of Shigella species is both an essential virulence factor and a protective antigen and that a critical level of serum immunoglobulin G (IgG) to this antigen will confer immunity to shigellosis. Because covalent attachment of polysaccharides to proteins increases their immunogenicity, especially in infants and in young children, the O-SP of Shigella species were bound to medically useful proteins, and the safety and immunogenicity of the resultant conjugates were confirmed in adults and 4- to 7-year-old children. Succinylation of the carrier protein improved the immunogenicity of Shigella conjugates in mice and increased their yield. Based on these results, a clinical trial of O-SP conjugates of Shigella sonnei and Shigella flexneri 2a bound to succinylated mutant Pseudomonas aeruginosa exotoxin A (rEPAsucc) or native or succinylated Corynebacterium diphtheriae toxin mutant (CRM9 or CRM9succ) was conducted in healthy adults. The conjugates were safe and immunogenic. S. sonnei-CRM9, S. sonnei-CRM9succ, and S. sonnei-rEPAsucc elicited significant rises of geometric mean (GM) IgG anti-LPS within 1 week of injection (P < 0.001). At 26 weeks, the GM anti-LPS levels elicited by these three conjugates were similar and higher than their prevaccination levels (P < 0.0001). GM IgG anti-LPS levels elicited by S. flexneri 2a-rEPAsucc were significantly higher than those elicited by S. flexneri 2a-rCRM9succ at all intervals after injection. At 26 weeks, the levels of IgG anti-LPS in vaccinees were higher than their prevaccination levels (P < 0.0001). The serum antibody responses were specific, as there was no significant rise of anti-LPS to the heterologous O-SP in any vaccinee. Both conjugates elicited statistically significant rises of serum antibodies to the injected carrier protein. At 6 months, these five Shigella conjugates elicited higher fold rises than similar conjugates (D. N. Taylor et al., Infect. Immun. 61:3678-3687, 1993). Based on these data, we chose S. sonnei-CRM9 and S. flexneri 2a-rEPAsucc for evaluation in children.

Adolescent↗

Successful treatment of antiepileptic drug hypersensitivity syndrome with intravenous immune globulin.

Intravenous immune globulin (IVIG) has proved beneficial for severe immunologically related cutaneous adverse reactions. We report a child with severe antiepileptic drug hypersensitivity syndrome who was successfully treated with IVIG. IVIG should be considered in the pharmacologic armamentarium of severe antiepileptic drug hypersensitivity syndrome. antiepileptic drugs, hypersensitivity, immune globulin.

Anticonvulsants↗

Cost-benefit analysis of active vaccination campaigns against hepatitis A among daycare centre personnel in Israel.

OBJECTIVE: To evaluate, in economic terms, active vaccination campaigns against hepatitis A in comparison with the use of nonspecific immune globulin for the prevention of the disease among daycare centre employees in Israel. SETTING: Hypothetical analysis of the costs and benefits related to vaccination campaigns of workers currently employed in daycare centres in Israel. METHODS: A cost-benefit analysis was performed, comparing mass and selective active vaccination strategies for the daycare centre working force. Direct and indirect costs of diagnosis, treatment and immunisation as well as productivity loss were considered. A Markov-based model was developed using data from previous epidemiological studies and literature. RESULTS: The benefit-to-cost ratios of selective and mass active vaccination strategies were 1.50 [net present value (NPV) $US606 396] and 0.04 (NPV-$US2.36 million), respectively (2000 values). CONCLUSION: Under these study assumptions, the practice of administering hepatitis A active vaccine to serologically proven non-immune daycare centre workers has a cost-benefit justification, and should be widely considered in countries with a similar hepatitis A epidemiology to that in this study.

Adolescent↗

Severe allergic bronchopulmonary aspergillosis in an infant with cystic fibrosis and her asthmatic father.

An infant with cystic fibrosis and her asthmatic father were diagnosed as suffering from allergic bronchopulmonary aspergillosis (ABPA). Cystic fibrosis was diagnosed in the infant at 6 weeks of age, and gene mutations were W1282X/G542X. She was diagnosed definitively as suffering from ABPA at age 3.5 years, but had suggestive symptoms from age 11 months. This may be the youngest age described to date for ABPA. The child responded well to systemic steroid therapy, but remained steroid-dependent over the next 4 years. Treatment with itraconazole enabled a marked reduction in steroid dosage. The father was an asthmatic, and a heterozygote for the cystic fibrosis transmembrane regulator (CFTR) mutation W1282X. He had a normal sweat test, atopy, and moderate reversible airway obstruction. There was no proven exposure to Aspergillus in the home environment. The importance of considering the diagnosis of ABPA even in infancy, the therapeutic dilemmas, and the possible role of abnormal CFTR function in the development of ABPA are discussed.

Adult↗

Seven-year study of bacteraemic pneumonia in a single institution.

In order to enhance current knowledge of nosocomial and community-acquired bacteraemic pneumonia in a single tertiary hospital in Israel, a 7-year study was conducted. Using a computerised database, all patients who had bacteraemic pneumonia from March 1988 to August 1995 were studied. During the study period, pneumonia was the source of bacteraemia in 319 of 4,548 (7%) episodes, occurring in 295 patients; 211 (66%) episodes were community-acquired and 108 (34%) were nosocomial. The microoroganisms isolated most frequently from patients with community-acquired bacteraemic pneumonia were Streptococcus pneumoniae (46%), Staphylococcus aureus (10%) and Haemophilus influenzae (8%); while Pseudomonas spp. (17%), Klebsiella spp. (11%) and Staphylococcus aureus (10%) were isolated most often from the patients with nosocomial bacteraemic pneumonia. The median age of patients was 68 years (range, 0.003-100). The overall mortality was 34%. No significant difference was found between the mortality rates of patients with community-acquired (31%) and nosocomial (40%) bacteraemic pneumonia (P=0.1). Multivariate analysis showed that hypothermia, respiratory failure, impaired consciousness, tracheal intubation, Staphylococcus aureus aetiology, septic shock, inappropriate empiric antibiotic treatment and age significantly increased mortality.

Aged↗

Clinical and laboratory impact of coagulase-negative staphylococci bacteremia in preterm infants.

UNLABELLED: A retrospective evaluation of the clinical and laboratory impact of coagulase-negative staphylococci (CONS) bacteremia in preterm infants was carried out. The study population included all preterm infants (n = 31) in whom two or more blood cultures were positive for CONS within a period of 4 d, with negative blood cultures 1 wk before and 1 wk after the CONS bacteremia. Clinical manifestations and the results of laboratory tests 7 d before and after the positive blood cultures, and on the first day of sepsis, were recorded and compared. During CONS bacteremia, the infants demonstrated apnoea and bradycardia (88%) and a need for oxygen (59%) and ventilatory support (69%). Significant laboratory findings were leukopenia below 5,000 cells/mm3 (12%), leukocytosis above 30,000 cells/mm3 (39%), and thrombocytopenia below 150,000/mm3 (25%). These clinical and laboratory manifestations differed significantly during the bacteremia infection compared with the week before and after. CONCLUSION: CONS bacteremia is a clinically significant infection in preterm infants, causing episodes of apnoea and bradycardia, and a need for ventilatory support.

Anti-Bacterial Agents↗

Liver enzyme abnormalities in gram-negative bacteremia of premature infants.

BACKGROUND: Hyperbilirubinemia and liver enzyme abnormalities are commonly observed in sepsis. However, the frequency in premature neonates and the specific relation to gram-negative bacteria are not known. PATIENTS AND METHODS: Charts of all preterm infants who had positive blood cultures for either gram-negative bacteria or coagulase-negative staphylococci were reviewed. Neonates with gram-negative bacteremia (n = 54) were compared with neonates with coagulase-negative staphylococcal bacteremia (n = 31). In addition infants with gram-negative bacteremia and elevated liver enzymes (n = 25) were compared with infants with gram-negative bacteremia and normal liver enzymes (n = 29). RESULTS: Liver enzyme abnormalities accompanied 46.3% (25 of 54) of gram-negative bacteremia and 12.9% (4 of 31) of episodes of coagulase-negative staphylococcal bacteremia (P = 0.002). Serum concentrations of liver enzymes were significantly higher in infants with gram-negative bacteremia than in those with coagulase-negative staphylococcal bacteremia (P < 0.0001), but no difference in alkaline phosphatase serum values was observed. Infants with gram-negative bacteremia and elevated liver enzymes were not fed for a longer period than infants with gram-negative bacteremia and normal liver enzymes (7.3 +/- 6.3 days vs. 4.0 +/- 4.3 days, P = 0.03), and this was accompanied by significant conjugated hyperbilirubinemia (P < 0.0001). Ventilation, total parenteral nutrition and medications were not responsible for the observed differences. Klebsiella pneumoniae bacteremia was commonly associated with elevated liver enzymes (12 of 18), whereas none of the infants with Pseudomonas aeruginosa bacteremia had elevated liver enzymes. CONCLUSIONS: Gram-negative bacteremia is commonly associated with cholestasis in premature neonates. Liver enzyme abnormalities are more common than elevated conjugated bilirubin, not all gram-negative bacteria have the same effect and the lack of enteral feeding seems to play a more significant role than the administration of parenteral nutrition.

Bacteremia↗