Meir Raz

Nasopharyngeal Carriage of Streptococcus pneumoniae by Adults and Children in Community and Family Settings

The rate of Streptococcus pneumoniae carriage among adults was compared with that among children (age, < or =6 years) in the same population. Nasopharyngeal culture results for 1300 adults and 404 children were analyzed. S. pneumoniae was carried by only 4% of the adults, compared with 53% of children in the same community. Young age, day care center attendance, having young siblings, and no antibiotic use during the month before screening were associated with the high carriage rate among children, whereas the only risk factor associated with carriage among adults was the presence of a respiratory infection on the screening day. S. pneumoniae serotype distribution and antibiotic resistance patterns differed between adults and children. Isolates of the same serotype--even of the same clone--differed in their antibiotic susceptibility patterns between children and adults. In a subanalysis of 151 pairs of children and their parents and of 32 pairs of siblings, intrafamilial transmission of S. pneumoniae could not be demonstrated.

Effect of N-Acetylcysteine on Air Trapping in COPD: A Randomized Placebo-Controlled Study

BACKGROUND FEV(1) is used for the classification of disease severity and is a good predictor of COPD mortality. However, it is a poor predictor of clinical symptoms, exercise tolerance, and response to bronchodilators in COPD. Progressive reduction in inspiratory capacity (IC) during exercise reflects dynamic hyperinflation and is a good predictor of decreased exercise ability as well as increased exertional dyspnea. In animal models of COPD, N-acetylcysteine (NAC), an antioxidant/mucous modifier, has been shown to modify small airways, which mainly causes lung hyperinflation. OBJECTIVE Our goal was to examine the effect of 1,200 mg/d of NAC on lung hyperinflation at rest and after exercise in patients with moderate-to-severe COPD. METHODS This was a randomized, double-blind, cross-over study that included 24 eligible patients > 40 years of age with a diagnosis of COPD, a FEV(1) < 70% of predicted, FEV(1)/FVC ratio < 0.70, and a functional residual capacity > 120% of predicted normal. Patients were randomized to placebo treatment or NAC treatment twice daily for 6 weeks. This was followed by a 2-week washout period, and then patients were crossed over to alternate therapy for an additional 6 weeks. Evaluation was performed after each 6 weeks of each treatment. RESULTS IC and FVC were higher especially after exercise after NAC treatment compared with placebo treatment. In addition, the relationship of residual volume to total lung capacity was reduced in a similar pattern. Furthermore, endurance time was longer after NAC treatment compared with placebo treatment. CONCLUSIONS NAC treatment of patients with stable, moderate-to-severe COPD has a beneficial effect on physical performance, probably due to a reduction in air trapping. TRIAL REGISTRATION Clinicaltrials.gov Identifier: NCT00476736.

The pneumococcal pilus predicts the absence of Staphylococcus aureus co-colonization in pneumococcal carriers

The determinants of the negative association between Streptococcus pneumoniae and Stapylococcus aureus colonization are unknown. In this matched case-control study, the odds of co-colonization with S. aureus were significantly lower for individuals carrying a piliated versus a nonpiliated S. pneumoniae strain, suggesting the pilus may be a determinant of the negative association.

A Typical Hospital-Acquired Methicillin-Resistant Staphylococcus aureus Clone Is Widespread in the Community in the Gaza Strip

Epidemiological data on community acquired methicillin-resistant-Staphylococcus aureus (CA-MRSA) carriage and infection in the Middle-East region is scarce with only few reports in the Israeli and Palestinian populations. As part of a Palestinian-Israeli collaborative research, we have conducted a cross-sectional survey of nasal S. aureus carriage in healthy children and their parents throughout the Gaza strip. Isolates were characterized for antibiotic susceptibility, mec gene presence, PFGE, spa type, SCCmec-type, presence of PVL genes and multi-locus-sequence-type (MLST). S. aureus was carried by 28.4% of the 379 screened children-parents pairs. MRSA was detected in 45% of S. aureus isolates, that is, in 12% of the study population. A single ST22-MRSA-IVa, spa t223, PVL-gene negative strain was detected in 64% of MRSA isolates. This strain is typically susceptible to all non-β-lactam antibiotics tested. The only predictor for MRSA carriage in children was having an MRSA carrier-parent (OR = 25.5, P = 0.0004). Carriage of the Gaza strain was not associated with prior hospitalization. The Gaza strain was closely related genetically to a local MSSA spa t223 strain and less so to EMRSA15, one of the pandemic hospital-acquired-MRSA clones, scarcely reported in the community. The rapid spread in the community may be due to population determinants or due to yet unknown advantageous features of this particular strain.

Reduction in Antibiotic Use Following a Cluster Randomized Controlled Multifaceted Intervention: The Israeli Judicious Antibiotic Prescription Study

BACKGROUND Antibiotic overuse is of great public health concern. This study assessed whether intervention among physicians and their treated population could achieve a sustained reduction in antibiotic use, specifically in classes known to promote antibiotic resistance among children in a community setting. METHODS We performed a cluster randomized controlled multifaceted trial among 52 primary care pediatricians and the 88,000 children registered in their practices. The intervention was led by local leaders and engaged the participating physicians. It included physician focus group meetings, workshops, seminars, and practice campaigns. These activities focused on self-developed guidelines, improving parent and physician knowledge, diagnostic skills, and parent-physician communication skills that promoted awareness of antibiotic resistance. The main outcome measure was the change in annual antibiotic prescription rates (APRs) of children treated by the intervention group physicians as compared with rates among those treated by control group physicians. The study comprised a 2-year pre-intervention period, a 3-year intervention period, and a 1-year follow-up period. Mixed-effect models were used to assess risk ratios to account for the clustered study design. RESULTS A decrease in the total APR among children treated by the intervention physicians compared with those treated by the control physicians was observed in the first intervention year (APR decrease among control physicians, 40%; APR decrease among intervention physicians, 22%; relative risk [RR], .76; 95% confidence interval [CI], .75-.78). This reduction crossed over all antibiotic classes but was most prominent for macrolides (macrolide prescription rate among control physicians, 58%; macrolide prescription rate among intervention physicians, 27%; RR, .58; 95% CI, .55-.62). The effect was sustained during the 4 following years. CONCLUSIONS. Multifaceted intervention that engages the physicians in an educational process is effective in reducing APRs and can be sustained. CLINICAL TRIALS REGISTRATION NCT01187758.

Three years of pulmonary rehabilitation: inhibit the decline in airflow obstruction, improves exercise endurance time, and body-mass index, in chronic obstructive pulmonary disease.

BackgroundPulmonary rehabilitation is known to be a beneficial treatment for COPD patients. To date, however, there is no agreement for how long a rehabilitation program should be implemented. In addition, current views are that pulmonary rehabilitation does not improve FEV1 or even slow its decline in COPD patients. The aim of the study was to examine the efficacy of a 3 year outpatient pulmonary rehabilitation (PR) program for COPD patients on pulmonary function, exercise capability, and body mass index (BMI).MethodsA matched controlled trial was performed with outcome assessments evaluated at 6, 12, 18, 24, 30, and 36 months. Eighty patients with moderate to severe COPD (age 63 ± 7 years; FEV1 48% ± 14) were recruited. The control group received standard care only, while in addition, the case study group received PR for duration of three years. These groups were matched for age, sex, BMI, FEV1% and number of pack-years smoked.ResultsThe decline in FEV1 after the three years was significantly lower in the PR group compared to control, 74 ml versus 149 ml, respectively (p < 0.001). Maximal sustained work and endurance time improved after a short period of PR and was maintained throughout the study, in contrast to the control group (p < 0.01). A decreased BMI was noted in the control group after three years, while in the PR group a mild improvement was seen (p < 0.05).ConclusionThree years of outpatient pulmonary rehabilitation resulted in modifying the disease progression of COPD, as well as improving physical performance in these patients.

Independent Risk Factors for Carriage of Penicillin-non-susceptible Streptococcus pneumoniae

Antibiotic treatment, day-care center (DCC) attendance and young age are associated with penicillin-non-susceptible Streptococcus pneumoniae (PNSSp) carriage. Yet, it is unclear whether each is an independent risk factor for the individual. This cross-sectional surveillance study was designed to answer this question. Nasopharyngeal cultures were obtained from 429 children (<6 y) during a visit to the pediatricians office. Two risk rates were calculated: the individuals absolute risk to carry PNSSp [simple odds ratio (ORS)] and the risk of an individual who is already a carrier [conditional odds ratio (ORC)]. Streptococcus pneumoniae was isolated from 52.7% of 401 children. PNSSp was detected in 37.1% of carriers. Independent risk factors were: young age [ORS 2.24, 95% confidence interval (95% CI) 1.2-4.2], DCC attendance (ORS 3.8, 95% CI 1.9-7.5), having young siblings (ORS 2.3, 95% CI 0.95-5.57) and each antibiotic treatment during the previous 3 months (ORS 1.5, 95% CI 1.25-1.85). The only significant risk factor among carriers was prior antibiotic treatment (ORC 2.24, 95% CI 1.64-3.05). Young children, who attended DCC and received 1 antibiotic course (9% of the population) had a risk 12.9 times higher than children without these features.

Parental Staphylococcus aureus Carriage is Associated With Staphylococcal Carriage in Young Children

Background: Staphylococcus aureus colonization typically precedes infection but risk factors for colonization in children are not well defined. Our previous study suggested that S. aureus carriage in children is associated with parental carriage. Here we wished to distinguish the different components that play a role in the risk to a child of a S. aureus–carrying parent. Methods: Between 2002 and 2005, children (0–40 months) and their parents were screened for carriage of S. aureus and Streptococcus pneumoniae during 1 of 6 surveys. Data were collected from the parents and the medical files. Multivariate analysis of possible associated factors and effect modifiers was carried out. Pulse-field gel electrophoresis was performed to determine strain relatedness. Results: A total of 4648 children were screened. S. aureus was isolated from 342 (7.6%) children and 992 (22%) parents. Pairs of parent-child carriers were found in 155 cases, over twice the rate expected by chance (1.66%, P < 0.0001). The variable that was most significantly associated with carriage in children was having a parent carrier (OR: 3.35; 95% CI: 2.59–4.33), whereas close contact with peers (as assessed by day care centers attendance or having young siblings) was not associated with carriage. Children <3 months had the highest carriage rate and children aged 6 to 12 months had the lowest (25.4% and 4.3%, respectively, P < 0.0001). Breast-feeding was not associated with higher or lower carriage. In 30 of 150 strains studied, >70% parent-child strains were genetically identical. Conclusions: Parental S. aureus colonization, but not DCC attendance or having young siblings, is an independent predictor for staphylococcal carriage in young children.

Prevalence and genetic relatedness of community-acquired methicillin-resistant Staphylococcus aureus in Israel

The aims of the study presented here were to determine the prevalence of Staphylococcus aureus carriage and, specifically, community-acquired methicillin-resistant S. aureus (CA-MRSA) carriage in children and their parents in Israel and to determine the genetic relatedness of these isolates. S. aureus was isolated from 580 of 3,373 (17.2%) individuals screened. The predominant type identified by pulsed-field gel electrophoresis was strain ST45-MSSA (25%). Five MRSA isolates were detected, and two of these were classified as CA-MRSA, based on the following criteria: no previous contact with a healthcare facility, absence of a multidrug-resistant (MDR) phenotype, and presence of SCCmec type IV. Isolates were negative for pvl and were classified as ST-45-MRSA. Although CA-MRSA is still rare in Israel, the genetic relatedness of the strains found in this study to a successful MSSA clone warrants close follow up.

In Vitro Bactericidal Activity of Streptococcus pneumoniae and Bactericidal Susceptibility of Staphylococcus aureus Strains Isolated from Cocolonized versus Noncocolonized Children

ABSTRACT Streptococcus pneumoniae is bactericidal to Staphylococcus aureus in vitro. To determine whether this in vitro effect accounts for the inverse relation between S. pneumoniae and S. aureus colonization reported in previous epidemiologic studies, we compared S. pneumoniae and S. aureus strains from cocolonized children to those from noncocolonized children. Cocolonizing pneumococci were less bactericidal and cocolonizing staphylococci less susceptible to this effect; however, the magnitude of the effect was small. Thus, in vitro killing is not the major determinant of the pattern of cocolonization.