Enhanced surveillance of Staphylococcus aureus bacteraemia to identify targets for infection prevention

BACKGROUND

Surveillance of Staphylococcus aureus bacteraemia (SAB) in Scotland is limited to the number of infections per 100,000 acute occupied bed-days and susceptibility to meticillin.

AIM

To demonstrate the value of enhanced SAB surveillance to identify targets for infection prevention.

METHODS

Prospective cohort study of all patients identified with SAB over a five-year period in a single health board in Scotland. All patients were reviewed at the bedside by a clinical microbiologist.

FINDINGS

In all, 556 SAB episodes were identified: 261 (46.6%) were hospital-acquired; 209 (37.9%) were healthcare-associated; 80 (14.4%) were community-acquired; and in six (1.1%) the origin of infection was not hospital-acquired, but could not be separated into healthcare-associated or community-acquired. These were classified as non-hospital-acquired. Meticillin-resistant S. aureus (MRSA) bacteraemia was associated with hospital-acquired and healthcare-associated infections. In addition, there was a significantly higher 30-day mortality associated with hospital-acquired (31.4%) and healthcare-associated (16.3%) infections compared to community-acquired SAB (8.7%). Vascular access devices were associated with hospital-acquired SAB and peripheral venous cannulas were the source for most of these (43.9%). Community-acquired infections were associated with intravenous drug misuse, respiratory tract infections and skeletal and joint infections. Skin and soft tissue infections were more widely seen in healthcare-associated infections.

CONCLUSION

The data indicate that enhanced surveillance of SAB by origin of infection and source of bacteraemia has implications for infection prevention, empirical antibiotic therapy, and health improvement interventions.

Prevalence of Bartonella species, hemoplasmas, and Rickettsia felis DNA in blood and fleas of cats in Bangkok, Thailand

Flea infestations are common in Thailand, but little is known about the flea-borne infections. Fifty flea pools and 153 blood samples were collected from client-owned cats between June and August 2009 from veterinary hospitals in Bangkok, Thailand. Total DNA was extracted from all samples, and then assessed by conventional PCR assays. The prevalence rates of Bartonella spp. in blood and flea samples were 17% and 32%, respectively, with DNA of Bartonella henselae and Bartonella clarridgeiae being amplified most commonly. Bartonella koehlerae DNA was amplified for the first time in Thailand. Hemoplasma DNA was amplified from 23% and 34% of blood samples and flea pools, respectively, with 'Candidatus Mycoplasma haemominutum' and Mycoplasma haemofelis being detected most frequently. All samples were negative for Rickettsia felis. Prevalence rate of B. henselae DNA was increased 6.9 times in cats with flea infestation. Cats administered flea control products were 4.2 times less likely to be Bartonella-infected.

Granisetron vs ondansetron for prevention of nausea and vomiting in hematopoietic stem cell transplant patients: results of a prospective, double-blind, randomized trial

The serotonin type-3 (5-HT3) antagonists represent a significant advance in the prevention of acute nausea and vomiting (N/V) from highly emetogenic chemotherapy. We sought to determine if any differences in efficacy or adverse effects exist between two such agents, ondansetron and granisetron, during conditioning therapy for hematopoietic stem cell transplantation (HSCT). Patients were randomized to receive either ondansetron 0.15 mg/kg intravenously every 8 h or granisetron 10 microg/kg intravenously daily. Additionally, all patients received scheduled dexamethasone and lorazepam. Prophylaxis was continued until 24 h after completion of chemotherapy. Nausea and distress were measured subjectively with visual analog scales and emetic episodes were quantified. Of the 110 randomized patients, 96 were evaluable for efficacy and safety. No significant differences in efficacy were observed between the ondansetron- and granisetron-treated patients, evaluated by comparing the degree of nausea and distress, number of emetic episodes and overall control of emesis. The adverse effects were also comparable and no patients were removed from study because of severe toxicities. This trial demonstrates that ondansetron and granisetron are equally effective at preventing acute N/V associated with conditioning therapy frequently used for HSCT. The agent of choice should be based on drug acquisition cost or preference.

Inhaled steroids as prophylaxis for delayed pulmonary toxicity syndrome in breast cancer patients undergoing high-dose chemotherapy and autologous stem cell transplantation

PURPOSE

To evaluate the efficacy of inhaled fluticasone propionate (Flovent) as prophylaxis against delayed pulmonary toxicity syndrome (DPTS) and decline in pulmonary function in breast cancer patients undergoing high-dose chemotherapy with the conditioning regimen of cyclophosphamide, cisplatin, and carmustine (CPB) followed by autologous stem cell transplantation (ASCT).

PATIENTS AND METHODS

Sixty-three consecutive patients with multinode-positive or metastatic breast cancer undergoing high-dose chemotherapy with CPB and ASCT who were treated at the Duke University Adult Bone Marrow Transplant Program. All patients were started on inhaled fluticasone propionate, 880 microg every 12 hours, for 12 weeks from the start date of their CPB conditioning regimen. Pulmonary function tests (PFTs) with a single-breath diffusing capacity of carbon monoxide (DLCO) were performed pre-ASCT as well as approximately 6 and 12 weeks post-ASCT. DPTS was defined as follows: (1) development of a nonproductive cough and dyspnea with or without fever, plus a fall in DLCO to less than 60% predicted; or (2) decline in DLCO to less than 50% predicted with or without symptoms.

RESULTS

Pulmonary function tests were done on all patients pre-ASCT, on 56 of the 63 patients at a median of 44 days (range, 25 to 73 days) post-ASCT, and on 51 of the 63 patients at a median of 96 days (range, 50 to 190 days) post-ASCT. The PFTs showed an average of an 8% (+/-26%) and 21% (+/-22%) decline in DLCO. These declines compare favorably with our historical control group of 45 consecutive breast cancer patients undergoing ASCT with CPB as a conditioning regimen, who experienced average declines in DLCO of 29% (+/-18%) (P < .001) and 33% (+/-18%) (P < .001) at comparable time periods post-ASCT. Delayed pulmonary toxicity syndrome occurred in 35% of treated patients compared to 73% of the historical controls (P = .0003). No patients died of DPTS or pulmonary problems, and there were no fungal pneumonias.

CONCLUSION

Inhaled fluticasone propionate may decrease the incidence of DPTS in patients treated with CPB as a conditioning regimen for ASCT, as well as help to preserve pulmonary function as measured by DLCO. These results are worthy of further study in a randomized clinical trial.

Development of logical reasoning: children's ability to verbally explain the nature of the distinction between logical and nonlogical forms of argument

Previous research by D. Moshman and B. Franks (1986) supported the hypothesis that children do not explicitly understand the nature of the distinction between logical and nonlogical forms of argument. This research examined the performance of 8-11-year-olds (N = 220) on Moshman and Franks's experimental tasks when the children were cued to apply particular comprehension strategies. Findings from 2 experiments indicated that a significant number of children are capable of explicitly recognizing the necessity of logical forms and the indeterminacy of nonlogical forms and that this competence must be distinguished from their tendency to fail to attend to structural relationships between propositions and to monitor the intrusion of extraneous personal knowledge in assessing the validity of an argument. The findings suggest that all of these competencies are important components of the ability to distinguish logical and nonlogical arguments.

Understanding of logical necessity: developmental antecedents and cognitive consequences

Does abstract reasoning develop naturally, and does instruction contribute to its development? In an attempt to answer these questions, this article specifically focuses on effects of prolonged instruction on the development of abstract deductive reasoning and, more specifically, on the development of understanding of logical necessity. It was hypothesized that instructional emphasis on the metalevel of deduction within a knowledge domain can amplify the development of deductive reasoning both within and across this domain. The article presents 2 studies that examine the development of understanding of logical necessity in algebraic and verbal deductive reasoning. In the first study, algebraic and verbal reasoning tasks were administered to 450 younger and older adolescents selected across different instructional settings in England and in Russia. In the second study, algebraic and verbal reasoning tasks were administered to 287 Russian younger and older adolescents selected across different instructional settings. The results support the hypothesis, indicating that prolonged instruction with an emphasis on the metalevel of algebraic deduction contributes to the development of understanding of logical necessity in both algebraic and verbal deductive reasoning. Findings also suggest that many adolescents do not develop an understanding of logical necessity naturally.

Overview of the management of AIDS-related Kaposi's sarcoma

OBJECTIVE

To review the epidemiology, pathogenesis, clinical presentation, diagnosis, and staging of Kaposi's sarcoma (KS), as well as the current role of local and systemic therapies in the management of AIDS-related KS (AIDS-KS).

DATA SOURCES AND STUDY SELECTION

MEDLINE and CANCERLIT searches of the English-language medical literature were conducted. Emphasis was placed on studies published since the onset of the AIDS epidemic in the early 1980s. A manual review of selected bibliographies was also completed.

DATA SYNTHESIS

AIDS-KS is a disease with a heterogeneous presentation that affects approximately 20% of patients with AIDS. Although the proportion of AIDS patients developing this disease during the course of their illness is declining, the actual number of AIDS-KS cases is increasing. The etiology of AIDS-KS is not clear, but a sexually transmitted cofactor has been implicated. Recent reports demonstrate that a herpes-like virus may be responsible for the development of KS in patients with and without AIDS. Furthermore, the cellular origin of KS has not been identified and questions remain about whether KS represents a true malignancy. The system used in staging patients with AIDS-KS has changed dramatically since initial therapeutic trials were conducted; this may account for observed differences in outcome among trials. The immunologic status of patients is now included as part of the staging system, since it has prognostic significance. Since specific therapy for AIDS-KS is not curative and does not prolong survival, it should be directed at improving patient cosmesis and palliation of disease-related symptoms. Local therapy, such as radiation, cryotherapy, and intralesional chemotherapy, is recommended for the management of limited disease. Systemic interferon alfa or chemotherapy is indicated for disseminated disease. Interferon alfa is useful in patients with predominantly mucocutaneous disease and is most effective in patients with good prognostic factors, such as absence of B symptoms, no history of opportunistic infections, and a CD4 count of more than 200 cells/mm3. Interferon alfa alone or in combination with zidovudine produces responses in approximately 30% of AIDS-KS patients with good prognostic factors. Single-agent or combination chemotherapy is indicated for rapidly progressive or advanced AIDS-KS. Commonly used agents include doxorubicin, daunorubicin, bleomycin, vincristine, and vinblastine. Responses can be expected in at least 50% of patients treated with single-agent or combination chemotherapy. However, many patients are unable to tolerate the toxicity associated with systemic AIDS-KS therapy. Future research will focus on therapies that target the underlying pathogenesis of this disease.

CONCLUSIONS

The optimal therapy for patients with AIDS-KS has not been determined. Treatment is appropriately directed at palliation of disease-related symptoms as no therapy has been unequivocally proven to impact survival. Local therapies should be used in the management of localized disease, while systemic therapy is appropriate for disseminated disease. Interferon alfa is useful in patients with primarily mucocutaneous disease or asymptomatic visceral involvement. Chemotherapy is indicated in patients who have rapidly progressive or advanced disease. Therapy must be individualized according to the patient's disease course and other patient-specific factors.