The population structure of Staphylococcus aureus among general practice patients from The Netherlands

To investigate the prevalence, the antibiotic resistance pattern and the population structure of Staphylococcus aureus , S. aureus isolates from the anterior nostrils of patients of general practitioners (GPs) were analysed. Insight into the S. aureus population structure is essential, as nasal carriers of S. aureus are at increased risk of developing an S. aureus infection. S. aureus was isolated from nasal swabs from 2691 patients with no sign of an infection collected in 29 GP practices in The Netherlands. The susceptibility pattern for several classes of antibiotics was determined, as well as the S. aureus genetic background, using spa typing. S. aureus was isolated from 617 of the 2691 (23%) nasal swabs. The prevalences of resistance to ciprofloxacin, co-trimoxazole, fusidic acid, macrolides and mupirocin were 0.2%, 0%, 6%, 5% and 1%, respectively. Half of the isolates were associated with a genetic background common to the major methicillin-resistant S. aureus (MRSA) clones, e.g. clonal complex (CC)1, CC5, CC8, CC22, CC30 and CC45, and the remainder were mainly associated with CC7, CC12, CC15, CC26, CC51 and CC101. The low prevalences of resistance suggest that, in the Dutch situation, S. aureus isolates from patients visiting their GP because of complaints not related to infection do not represent a large reservoir of antibiotic resistance genes. Although no MRSA isolates were found, the genetic background of some of the S. aureus isolates is commonly observed among community-associated (CA)-MRSA clones (CC1, CC8 and CC30), and this might suggest that these isolates have the potential to become CA-MRSA.     

Genetic diversity of methicillin-resistant <Emphasis Type="Italic">Staphylococcus aureus</Emphasis> in a tertiary hospital in The Netherlands between 2002 and 2006

The aim of this study was to investigate the methicillin-resistant Staphylococcus aureus (MRSA) clones isolated in a Dutch university hospital, situated near the borders of Belgium and Germany, between 2002 and 2006. MRSA strains (n = 175) were characterized using spa and SCCmec typing. The presence of Panton Valentine leukocidin (PVL) was determined. Between 2002 and 2005, ST5-MRSA-IV was predominant, and the spa type of ST5-MRSA-IV changed from t002 to t447. ST5-MRSA-I, ST5-MRSA-II, ST228-MRSA-I, and ST247-MRSA-I were also observed in this period. From 2004, the MRSA genetic background became more diverse, and in 2006, ST5-MRSA-IV was only sporadically observed. From 2005, ST5-MRSA-II, ST8-MRSA-IV, ST22-MRSA-IV, and ST45-MRSA-IV were increasingly observed. Several other MRSA clones, such as ST239-MRSA-III, were found sporadically. Four PVL-positive MRSA isolates were observed, associated with ST80-MRSA-IV and ST8-MRSA-IV. ST5-MRSA-I, ST5-MRSA-II, ST5-MRSA-IV, and ST228-MRSA-I have not been described previously in The Netherlands.     

Preliminary In Vitro Antisickilng Properties of Crude Juice Extracts of Persia Americana,Citrus Sinensis,Carica Papaya and Ciklavit?

The antisickling properties of crude juice extracts of the edible portions of three commonly consumed tropical fruits namely Persia americana, Citrus sinensis, and Carica papaya were investigated in vitro alongside a new drug preparation called Ciklavit® that has antisickling activity. Four different solvent extracts of the crude juice of each fruit including aqueous, acidic, alkaline and alcoholic extracts were prepared and their antisickling effects on sickle cell trait (HbAS) and sickle cell disease (HbSS) blood samples checked alongside Ciklavit®. Blood samples were stabilized using normal saline and the antisickling effects were checked by counting the number of sickle cells remaining after incubation of the blood samples with the crude fruit extracts and Ciklavit® for twenty-four hours. The results showed that Ciklavit® produced a sustained reduction in the number of sickle cells in both HbAS and HbSS blood samples. Also the alkaline and alcoholic extracts of P. americana and C. papaya produced significant reduction in the number of sickle cells.     

Relation between regional and global systolic function in patients with ischemic cardiomyopathy after β-Blocker therapy or revascularization

Background

To assess the relationship between improved regional and global myocardial function in patients with ischemic cardiomyopathy in response to β-blocker therapy or revascularization.

Materials and methods

Cardiovascular Magnetic Resonance (CMR) was performed in 32 patients with ischemic cardiomyopathy before and 8 ± 2 months after therapy. Patients were assigned clinically to β-blocker therapy (n = 20) or revascularization (n = 12). CMR at baseline was performed to assess regional and global LV function at rest and under low-dose dobutamine. Wall thickening was analyzed in dysfunctional, adjacent, and remote segments. Follow-up CMR included rest function evaluation.

Results

Augmentation of wall thickening during dobutamine at baseline was similar in dysfunctional, adjacent and remote segments in both patient groups. Therefore, baseline characteristics were similar for both patient groups. In both patient groups resting LV ejection fraction and end-systolic volume improved significantly (p < 0.05) at follow-up. Stepwise multivariate analysis revealed that improvement in global LV ejection fraction in the β-blocker treated patients was significantly related to improved function of remote myocardium (p < 0.05), whereas in the revascularized patients improved function in dysfunctional and adjacent segments was more pronounced (p < 0.05).

Conclusion

In patients with chronic ischemic LV dysfunction, β-Blocker therapy or revascularization resulted in a similar improvement of global systolic LV function. However, after β-blocker therapy, improved global systolic function was mainly related to improved contraction of remote myocardium, whereas after revascularization the dysfunctional and adjacent regions contributed predominantly to the improved global systolic function.     

Subcutaneous ventricular catheter reservoir and ventriculoperitoneal drain-related infections in preterm infants and young children

Objective   In the period January 1990 to September 1997, 70 patients, aged under 6 years were treated for hydrocephalus with a subcutaneous ventricular catheter reservoir and/or a ventriculoperitoneal drain at the University Hospital of Maastricht.
Methods   By means of a retrospective chart analysis, the number of shunt infections and related risk factors were analyzed.
Results   Twenty-one patients (30%) developed one or more infections, with an infection rate of 15.2% per surgical event. For an implanted reservoir or drain, the infection rates were 15.9 and 16.4%, respectively. The study group consisted of 39 (55.7%) preterm infants (<37 weeks) and 31 (44.3%) full-term infants (37 weeks), with infection rates of 33.3 and 25.8%, respectively. At the first surgical intervention 28 patients (40%) had a postmenstrual age less than 37 weeks, with an infection rate of 46.4%. At the time of surgery, 69.7% of the patients were aged less than 6 months, with an infection rate of 19.6%. The most frequent causative microorganism of the shunt infections was Staphylococcus epidermidis (42.1%).
Conclusions   Prematurity is an important risk factor for ventricular catheter reservoir and ventriculoperitoneal drain-related infections, especially for patients with a postmenstrual age of less than 37 weeks at their initial shunt placement and extreme low birth weight infants have a high risk for infection. In our opinion the use of adequate antibiotic prophylaxis and optimal infection control measures are necessary to keep the rate of infection as low as possible.