The use of broad-range bacterial PCR in the diagnosis of infectious diseases: a prospective cohort study

OBJECTIVES

Broad-range PCR has the potential to detect virtually any bacterial species via amplification and nucleotide sequencing of a DNA region common to all bacteria. We aimed to evaluate its usefulness and clinical relevance when applied to a wide variety of primary sterile materials.

METHODS

A prospective study including 1370 samples (75 heart valves, 151 joint tissue samples, 230 joint aspirates, 848 whole blood samples and 66 culture-negative cerebrospinal fluid samples) were studied by using a commercial PCR system for detecting 16S rDNA (Molzym). The PCR results were compared with culture and were considered to provide added diagnostic value only if the PCR approach revealed new pathogens that were missed by culture.

RESULTS

The added value of PCR was evident in 173 of 555 PCR-positive samples (0.126; 0.109-0.144 (proportion from all tested samples; 95% confidence interval)), most frequently in examinations of heart valves (0.56; 0.448-0.672) and joint tissue samples (0.219; 0.153-0.284). In contrast, the lowest rate of PCR with added value was noted for blood samples, regardless of the patient cohort they had been drawn from (nononcologic patients from intensive care: 0.065; 0.043-0.087, haematooncologic children: 0.048; 0.027-0.070). Moreover, PCR missed up to 7.1% of blood culture findings (0.071; 0.048-0.095) regarded as clinically relevant, which was the second highest failure rate after joint tissue samples (0.099; 0.052-0.147).

CONCLUSIONS

Broad-range PCR substantially increases detection rate of pathogens, especially from heart valves and joint samples. However, a concurrent risk of false-negative PCR results justifies the need for parallel culture.

Insights into the cystic fibrosis care in Eastern Europe: Results of survey

BACKGROUND

The European cystic fibrosis (CF) Society Standards of Care were set to facilitate the delivery of high-quality care throughout Europe. However, their implementation may be difficult for less economically advantaged countries. This survey was performed to explore the gap in the knowledge of the level of CF care in Eastern Europe.

METHODS

Questionnaires were sent online to one CF professional and one CF patient representative for every Eastern European country.

RESULTS

Although most respondents indicated the presence of CF centres, disparities in their framework among individual countries and between them and the European CF Standards of Care became apparent. A minority of countries achieved CF centre recognition by the government (6 of 16), provided CF care for adults (6 countries) and had a multidisciplinary team with all team members represented (2 countries). Patients were significantly more critical in the evaluation of various aspects of CF care than physicians, especially in the Balkan region.

CONCLUSIONS

The survey results indicate that the organization and level of CF care across Eastern Europe is largely variable and lacks some of its fundamental attributes in several countries.

Treated Autoimmune Thyroid Disease Is Associated with a Decreased Quality of Life among Young Persons with Type 1 Diabetes

Type 1 diabetes (T1D) in children and adolescents is relatively often accompanied by other immunopathological diseases, autoimmune thyroid disease (AITD) or celiac disease (CD). Our aim was to assess whether these conditions are associated with changes in the health-related quality of life (HRQOL) in pediatric patients with T1D. In a cross-sectional study we identified eligible 332 patients with T1D aged 8-18 years, of whom 248 (75%) together with their parents responded to the PedsQL Generic and Diabetes Modules. Compared to 143 patients without thyroid autoantibodies, 40 patients with a thyroxine-treated AITD scored lower in the overall generic HRQOL (P = 0.014), as well as in the overall diabetes-specific HRQOL (P = 0.013). After adjustment for age, gender, duration of diabetes, type of diabetes treatment, and diabetes control, this association remained statistically significant for the generic HRQOL (P = 0.023). Celiac disease was not associated with a change in the generic or diabetes-specific HRQOL (P = 0.07  and  P = 0.63, resp.). Parental scores showed no association with AITD or celiac disease, except a marginally significant decrease in the overall generic HRQOL (P = 0.039) in the T1D + AITD compared to T1D group. Our study indicates that, in pediatric patients with T1D, concomitant thyroxine-treated AITD is associated with lower quality of life.

Weekly and seasonal variation in the incidence of cardiac arrests

BACKGROUND

Patterns of temporal variation of cardiac arrests may be important for understanding mechanisms leading to the onset of acute cardiovascular disorders. Previous studies have reported diurnal variation of the onset of cardiac arrests, with high incidence in the morning and in the evening, lack of daily variation during the week, and some seasonal variation.

METHODS AND RESULTS

We explored weekly and yearly (seasonal) temporal variation in 6603 out-of-hospital cardiac arrests attended by the Seattle Fire Department. We observed daily variation that peaks on Monday and seasonal variation that peaks in the winter.

CONCLUSIONS

Cardiac arrests do not occur randomly during the week or year but follow certain periodic patterns. These patterns are probably associated with patterns of activities.

Circadian variations in the occurrence of cardiac arrests: initial and repeat episodes

BACKGROUND

Patterns of temporal variation of cardiac arrests may be important for understanding mechanisms leading to the onset of acute cardiovascular disorders. Previous studies reported diurnal variation of the onset of cardiac arrests, with high incidence in the morning and in the evening, lack of daily variation during the week, and some seasonal variation. The association between the time of day and recurrent cardiac arrests has not been previously examined.

METHODS AND RESULTS

We explored temporal variation in 6603 out-of-hospital cardiac arrests attended by the Seattle Fire Department. The data exhibit diurnal variation, with a low incidence at night and two peaks of approximately the same size (at 8 to 11 AM and 4 to 7 PM). The evening peak is attributed primarily to the patients found in ventricular fibrillation, whereas arrests that show other rhythms exhibit mainly a morning peak. Cardiac arrests associated with survival have more pronounced diurnal variation than episodes in which survival did not occur. This difference persists after adjustment for rhythm. For 597 patients who had at least two separate cardiac arrests, we found no overall association between the times of day of the recurrent arrests. For women, however, the times of day of the first and second arrests were closer to each other than one would expect if the times were entirely unrelated.

CONCLUSIONS

Cardiac arrests do not occur randomly during the day, but rather follow certain periodic patterns. These patterns are probably associated with patterns of daily activities. The hypothesis that cardiac arrests are triggered by a person's activity rather than by some underlying characteristics of his or her disease is supported by the lack of association between the times of the first and second arrests in the patients with recurrent arrests.

Logrank, play the winner, power and ethics

We show by simulation and numerical integration techniques that power is largely unaffected by play the winner strategies in a typical chronic disease mortality trial utilizing the logrank test. This raises the issue of the ethics of equal allocation in such a setting.

A simulation study used to design the sequential monitoring plan for a clinical trial

In designing a sequential monitoring plan for the AVID (Antiarrhythmics Versus Implantable Defibrillators) study, a multi-centred clinical trial, we completed a simulation study to help ourselves and the Data Safety Monitoring Board understand the implications of various monitoring plans. In particular, we compared three test statistics and three use functions. Simulation was based on approximate trial parameters and two plausible but distinct alternative hypotheses. The power to detect a difference between the two treatment arms was computed as a function of time. The simulated results illuminate several of the important statistical and ethical issues involved in selecting a sequential monitoring plan and illustrate how one can use simulations to design a clinical trial.