Yechiel Schlesinger

Cost-Effectiveness of Blood Cultures for Adult Patients with Cellulitis

To assess the cost-effectiveness of blood cultures for patients with cellulitis, a retrospective review was conducted of clinical and microbiological data for all 757 patients admitted to a medical center because of community-acquired cellulitis during a 41-month period. Blood cultures were performed for 553 patients (73%); there were a total of 710 blood samples (i.e., a mean of 1.3 cultures were performed per patient). In only 11 cases (2.0%) was a significant patient-specific microbial strain isolated, mainly beta-hemolytic streptococci (8 patients [73%]). An organism that was considered a contaminant was isolated from an additional 20 culture bottles (3. 6%). The cost of laboratory workup of the 710 culture sets was

Bacteremia due to beta-hemolytic streptococcus group g: increasing incidence and clinical characteristics of patients

36, 050. Isolation of streptococci led to a change from empirical treatment with cefazolin to penicillin therapy for 8 patients. All patients recovered. In conclusion, the yield of blood cultures is very low, has a marginal impact on clinical management, and does not appear to be cost-effective for most patients with cellulitis.

The risk of vascular infection in adult patients with nontyphi Salmonella bacteremia

PURPOSE To describe the epidemiology and clinical characteristics of patients diagnosed with Streptococcus group G bacteremia from 1990 to 1999 at a community teaching hospital in Israel. SUBJECTS AND METHODS We calculated the annual rate of bacteremia with Streptococcus group G, expressed as a percentage of positive blood cultures (after excluding contaminants) and per 1000 admissions. Medical records of patients with Streptococcus group G were reviewed. RESULTS During the 10-year study period, there was a total of 7415 positive blood cultures, 327 (4.4%) of which were beta-hemolytic Streptococcus species, of which 49 (15%) were group G. The rate of Streptococcus group G bacteremia per 1000 admissions increased from zero (0/18,783) in 1990 to 0.41 (13/31,440) in 1999 (P = 0.001), surpassing Streptococcus group A in frequency. Of the 47 patients with Streptococcus group G, 40 medical records were available for review: 25 patients (63%) were older than 75 years and 32 (80%) were men. The probable source of Streptococcus group G bacteremia was a skin or soft tissue infection in 37 patients (93%). Six of the 40 patients died. CONCLUSION Community-acquired group G streptococcal bacteremia occurred with increasing frequency from 1990 to 1999 at our hospital. Most patients were elderly men, and the portal of entry was usually the skin or soft tissue. Our findings suggest a change in the epidemiology of bacteremia due to beta-hemolytic streptococci.

Carriage rate of carbapenem-resistant Klebsiella pneumoniae in hospitalised patients during a national outbreak

Infections due to Salmonella are common, and their incidence appears to be increasing in many countries (1,2). Although S. typhi and S. paratyphi infect only humans, nontyphoidal Salmonella are widely spread in nature and are commonly associated with certain animals, eg, chickens. In humans, nontyphoidal Salmonella infections are most often associated with contaminated food products (3). Salmonellosis may manifest in five different clinical forms, including asymptomatic chronic carrier state, gastroenteritis, enteric fever, bacteremia, and extraintestinal localized complications of which endovascular infection is one of the most serious (4). Almost every arterial site in the body may become involved (5–7); however, infections of the aorta appear to be the most frequent (8 –10). There remain substantial questions regarding the relative frequency of vascular complications in Salmonella bacteremia, the optimal diagnostic approach, and the subsequent therapeutic management. We reviewed all patients with Salmonella bacteremia from a 10-year period (1990 to 1999) to determine the frequency of vascular complications, describe clinical details of 3 patients with Salmonella mycotic aneurysm, and review diagnostic methods and treatment.

Early impact of sequential introduction of 7-valent and 13-valent pneumococcal conjugate vaccine on IPD in Israeli children <5 years: An active prospective nationwide surveillance

During a national outbreak of carbapenem-resistant Klebsiella pneumoniae (CRKP) in Israel, we conducted a point prevalence survey to determine the extent of asymptomatic carriage. Subsequently, a retrospective case-control study was done, comparing carriers of CRKP with non-carriers, in order to detect risk factors for carriage. Oral, perianal and rectal swabs were obtained from all hospitalised eligible and consenting patients. Selective media for carbapenem-resistant Gram-negative bacteria were used and pulsed-field gel electrophoresis (PFGE) helped to determine clonal source. Culture was obtained from 298 patients. Sixteen (5.4%) were carriers of CRKP, with a higher carriage rate in medical and surgical wards. Only 18% of carriers were treated with any carbapenem prior to the survey. Five of the 16 carriers had a positive clinical specimen for CRKP, hence a clinical infection versus asymptomatic carriage ratio of 1:3. The rectum was the most sensitive site sampled, detecting 15/16 carriers, and the overall sensitivity of the method was 94% with a negative predictive value of 99.6%. In a multivariate analysis of risk factors for CRKP carriage, three variables were significantly related to carriage state: diaper use, longer duration of hospital stay and vancomycin use. PFGE demonstrated that all 16 isolates were identical, confirming clonal origin. A point prevalence survey performed at a single medical centre during an outbreak of CRKP demonstrated a carriage rate of 5.4%. The clonal origin of these isolates suggests that strict adherence to isolation procedure may contain this outbreak.

Chronic granulomatous disease in Israel : Clinical, functional and molecular studies of 38 patients

BACKGROUND The 7-valent pneumococcal conjugated vaccine (PCV7) was introduced to the Israeli national immunization plan (NIP) in July 2009 (administered at age 2, 4 and 12 months), with a fast reduction of invasive pneumococcal disease (IPD) caused by PCV7 serotypes. Starting in November 2010, PCV13 gradually replaced PCV7. AIM To report the impact of PCV7/PCV13 sequential introduction on IPD in Israeli children <5 years. METHODS An ongoing nationwide, prospective, population-based, active surveillance. All IPD episodes (Streptococcus pneumoniae isolated from blood and/or cerebrospinal fluid) from July 2004 through June 2013 were included. RESULTS Overall, 2670 IPD episodes were recorded. Incidence of IPD caused by PCV7+6A serotypes during the PCV13 period vs. pre-PCV period decreased by 95% (Incidence Rate Ratio [IRR]=0.05; 95% CI=0.03-0.09). This reduction was observed in a two-step manner: 90% in the PCV7-period and further 5% in the PCV13-period. The rates of IPD caused by the 5 additional PCV13-serotypes (1, 3, 5, 7F, 19A; 5VT) increased initially by 47%, but subsequently decreased by 79%, resulting in an overall 70% reduction during the entire study period (IRR=0.30; 0.21-0.44). A two-fold increase in non-PCV13 serotypes IPD was observed (IRR=2.43; 1.73-3.66). In total, a 63% reduction of all-serotype IPD episodes was observed in children <5 years (69% and 48% in children <2 and 2-4 years old, respectively). CONCLUSIONS After initiation of PCV NIP, a rapid and substantial 2-step IPD reduction was observed in children <5 years. The serotype-specific rate reduction reflected the sequential introduction of PCV7/PCV13.

Changing Epidemiology of Infective Endocarditis: A Retrospective Survey of 108 Cases, 1990–1999

Chronic granulomatous disease (CGD) is an innate immunodeficiency due to a genetic defect in one of the NADPH-oxidase components. In the course of 21 years, 38 Israeli CGD patients were diagnosed with 17 gene mutations, seven of which were new. Clinical, functional, and molecular studies were accomplished. Although X-linked recessive (XLR)-CGD is worldwide the most common genotype of the disease (~70%), in our study only 11 patients (29%) suffered from XLR-CGD. In Israel, the higher incidence of the autosomal recessive (AR) form of CGD (63%) may be related to consanguineous marriages. In three patients (8%), all four proteins of the NADPH oxidase were present. Severe clinical expression was found both in the XLR and AR forms, but in general a milder disease was evident in AR-CGD, particularly in patients with p47(phox) deficiency. Despite early and aggressive therapy, a mortality rate of 26% was noted. Given that bone-marrow transplantation was successful in five of seven patients, it is recommended to perform it as early as possible before tissue damage is irreversible.

Adult Patients with Occult Bacteremia Discharged from the Emergency Department: Epidemiological and Clinical Characteristics

Abstract.The aim of this study was to report the experience with infective endocarditis over the past decade, describe the changing clinical and epidemiological features of the disease, and attempt to determine the optimal number of blood culture sets required for diagnosis. All cases diagnosed during a 10-year period were reviewed clinically and microbiologically. In addition, a retrospective assessment of blood culture data was performed. From the period 1990–1999, 108 cases that met the von Reyn or Dukes criteria were recorded. The major underlying cardiac condition was the presence of a prosthetic valve (n=33 patients, 31%). Among patients with native valves, nonrheumatic valvular heart disease of the elderly was the most common underlying factor (n=19 patients, 25%). Overall, 13 patients (11%) died. Predictors on admission for increased mortality were shortness of breath, age >60 years, time to defervescence, erythrocyturia, hemoglobin level <10 g/dl, and leukocytosis >15,000 (all P<0.05). Analysis of blood culture data showed that the diagnostic yield among groups from whom either only one or more than six blood culture sets were drawn was reduced compared with that among groups from whom between two and five culture sets had been taken. The outcome of endocarditis in this series from a community hospital was much more favorable compared with that reported in surveys from large tertiary centers. Moreover, obtaining more than two or three blood cultures is neither helpful nor cost-effective in the initial assessment of patients with suspected endocarditis.

The role of procalcitonin as a predictor of nosocomial sepsis in preterm infants

To determine the epidemiological and clinical characteristics of patients who were discharged from the emergency department (ED) and subsequently proved to have bacteremia, we prospectively assessed all patients examined in the ED during an 18-month period from whose blood cultures a significant organism was isolated. Discharged patients were contacted and reevaluated. Two case-control studies were conducted, in which each study patient was matched with a total of 4 control patients. During the study period, 46,336 patients were examined in the ED; 78% were adults and 22% were children. Blood cultures were performed for 25% of the adult patients and for 44% of the children. Although the occurrence of occult bacteremia in patients who were discharged from the ED is 3.7 times more common in children than in adults, the absolute numbers of discharged adults and children with occult bacteremia are similar. Careful clinical assessment will not prevent discharge of some of these patients; however, these patients in general do well and can be safely recalled for reevaluation and complementation of therapy.

Longitudinal quantification of Ehrlichia canis in experimental infection with comparison to natural infection.

Aim: To assess the role of procalcitonin in detecting nosocomial sepsis in preterm infants, after the onset of clinical symptoms. Subjects: 100 preterm infants, 24–36 wk of gestation, were followed from the age of 3 d until discharge. Procalcitonin and C‐reactive protein (CRP) levels were measured within 3 d of sepsis workup events. Results: 141 blood samples were drawn from 36 infants during 85 episodes of sepsis workup performed between 4 and 66 d of life. Of these episodes, 51 (60%) were not a result of documented sepsis and thereby served as the negative comparison group. Median procalcitonin levels were higher in the septic group compared with the non‐septic group at the time of the sepsis workup (2.7 vs 0.5 ng/ml, p=0.003), at 1–24 h after the sepsis workup (4.6 vs 0.6 ng/ml, p=0.003), and at 25–48 h (6.9 vs 2.0 ng/ml, p=0.016). Using high cutoff levels, both procalcitonin (2.3 ng/ml) and CRP (30 mg/l) had high specificity and positive predictive value (97%, 91% and 96%, 87%, respectively) but low sensitivity (48% and 41%, respectively) to detect sepsis. Areas under the ROC curve for procalcitonin and CRP were 0.74 and 0.73, respectively.