Multicenter evaluation of the AMPLICOR and automated COBAS AMPLICOR CT/NG tests for detection of Chlamydia trachomatis

The fully automated COBAS AMPLICOR CT/NG and semiautomated AMPLICOR CT/NG tests were evaluated in a multicenter trial for the ability to detect Chlamydia trachomatis infections. Test performance compared to that of culture was evaluated for 2,236 matched endocervical swab and urine specimens obtained from women and for 1,940 matched urethral swab and urine specimens obtained from men. Culture-negative, PCR-positive specimens that tested positive in a direct fluorescent-antibody test or in a confirmatory PCR test for an alternative target sequence were resolved as true positives. The overall prevalences of chlamydia were 2.4% in women and 7.2% in men. The COBAS AMPLICOR and AMPLICOR formats yielded concordant results for 98.1% of the specimens. With the infected patient as the reference standard, the resolved sensitivities of COBAS AMPLICOR were 89.7% for endocervical swab specimens, 89.2% for female urine specimens, 88.6% for male urethral swab specimens, and 90.3% for male urine specimens. When results were analyzed as if only a single test had been performed on a single specimen type, the resolved sensitivity was always higher. The resolved specificities of PCR were 99.4% for endocervical swab specimens, 99.0% for female urine specimens, 98.7% for male urethral swab specimens, and 98.4% for male urine specimens. The internal control revealed that 2.4% of the specimens were inhibitory when initially tested. Nevertheless, valid results were obtained for 98.6% of the specimens because 59.1% of the inhibitory specimens were not inhibitory when a second aliquot was tested. The COBAS AMPLICOR and AMPLICOR CT/NG tests for C. trachomatis exhibited equally high sensitivity and specificity with both urogenital swab and urine specimens and thus are well suited for screening for C. trachomatis infection.

Multicenter evaluation of AMPLICOR and automated COBAS AMPLICOR CT/NG tests for Neisseria gonorrhoeae

The fully automated COBAS AMPLICOR CT/NG and semiautomated AMPLICOR CT/NG tests were evaluated in a multicenter trial for their ability to detect Neisseria gonorrhoeae infections. Test performance compared to that of culturing was evaluated for 2,192 matched endocervical swab and urine specimens obtained from women and for 1, 981 matched urethral swab and urine specimens obtained from men. Culture-negative, PCR-positive specimens that tested positive in a confirmatory PCR test for an alternative target sequence within the N. gonorrhoeae 16S rRNA gene were considered to be true positives. The overall prevalences of gonorrhea were 6.6% in women and 20.1% in men. The COBAS AMPLICOR and AMPLICOR formats yielded concordant results for 98.8% of the specimens and exhibited virtually identical sensitivities and specificities. The results that follow are for the COBAS AMPLICOR format. With the infected patient as the reference standard, the resolved sensitivities of PCR were 92.4% for endocervical swab specimens and 64.8% for female urine specimens. There were no significant differences in these rates between women with and without symptoms. Among symptomatic men, COBAS AMPLICOR sensitivities were 94.1% for urine and 98.1% for urethral swabs; for asymptomatic men, the results were 42.3 and 73.1%, respectively. In comparison, the sensitivities of culturing were 84.8% for endocervical specimens, 92.7% for symptomatic male urethral specimens, and only 46.2% for urethral specimens obtained from asymptomatic men. When PCR results were analyzed as if only a single test had been performed on a single specimen type, the resolved sensitivity was always higher. The resolved specificities of PCR were 99.5% for endocervical swab specimens, 99.8% for female urine specimens, 98.9% for male urethral swab specimens, and 99.9% for male urine specimens. The internal control revealed that 2.1% of specimens were inhibitory when initially tested. Nevertheless, valid results were obtained for 99.2% of specimens because 60.0% of the inhibitory specimens were not inhibitory when a second aliquot was tested. The COBAS AMPLICOR CT/NG test for N. gonorrhoeae exhibited high sensitivity and specificity with urethral swab and urine specimens from men and endocervical swab specimens from women and thus is well suited for diagnosing and screening for N. gonorrhoeae infection.

Delirium is a Common and Early Finding in Patients in the Pediatric Cardiac Intensive Care Unit

OBJECTIVE

To determine incidence, associated risk factors, and characteristics of delirium in a pediatric cardiac intensive care unit (CICU). Delirium is a frequent and serious complication in adults after cardiac surgery, but there is limited understanding of its impact in children with critical cardiac disease.

STUDY DESIGN

Single-center prospective observational study of CICU patients ≤21 years old. All were screened for delirium using the Cornell Assessment for Pediatric Delirium each 12-hour shift.

RESULTS

Ninety-nine patients were included. Incidence of delirium was 57%. Median time to development of delirium was 1 day (95% CI 0, 1 days). Children with delirium were younger (geometric mean age 4 vs 46 months; P < .001), had longer periods of mechanical ventilation (mean 35.9 vs 8.8 hours; P = .002) and had longer cardiopulmonary bypass times (geometric mean 126 vs 81 minutes; P = .001). Delirious patients had longer length of CICU stay than those without delirium (median 3 (IQR 2, 12.5) vs 1 (IQR1, 2) days; P < .0001). A multivariable generalized linear mixed model showed a significant association between delirium and younger age (OR 0.35 for each additional month, 95% CI 0.19, 0.64), need for mechanical ventilation (OR 4.1, 95% CI 1.7, 9.89), and receipt of benzodiazepines (OR 3.78, 95% CI 1.46, 9.79).

CONCLUSIONS

Delirium is common in patients in the pediatric CICU and is associated with longer length of stay. There may be opportunities for prevention of delirium by targeting modifiable risk factors, such as use of benzodiazepines.

Conserved estrogen binding and signaling functions of the G protein-coupled estrogen receptor 1 (GPER) in mammals and fish

Recent studies by several research groups have shown that G protein estrogen receptor-1 (GPER) formerly known as GPR30, mediates 17beta-estradiol (E2) activation of signal transduction pathways in a variety of human cancer cells and displays E2 binding typical of a membrane estrogen receptor. However, the importance of GPER as an estrogen receptor has been questioned by Otto and co-workers. Some of the pitfalls in investigating the functions of recombinant steroid membrane receptors that may explain the negative results of these investigators are discussed. The characteristics of GPER have also been investigated in a teleost fish, Atlantic croaker, where it has been shown to mediate E2 inhibition of oocyte maturation. Investigations on newly discovered homologous proteins from distantly related vertebrate groups are valuable for determining their fundamental, evolutionarily conserved functions. Therefore, the functions of croaker and human GPERs were compared. The comparisons show that croaker and human GPER have very similar estrogen binding characteristics, typical of estrogen membrane receptors, and activate the same estrogen signaling pathways via stimulatory G proteins (Gs) resulting in increased cAMP production. These results suggest that the estrogen binding and estrogen signaling functions of GPER arose early in vertebrate evolution, prior to the divergence of the teleosts from the tetrapods, more than 200 million years ago. The finding that estrogen membrane signaling through GPER has been conserved for such a long period in two distantly related vertebrate groups, mammals and fish, suggests that this is a fundamental function of GPER in vertebrates, and likely its major physiological role.

Enhancing the specificity of the COBAS AMPLICOR CT/NG test for Neisseria gonorrhoeae by retesting specimens with equivocal results

The COBAS AMPLICOR CT/NG test for Neisseria gonorrhoeae cross-reacts with certain strains of nonpathogenic Neisseria species. In some strains, the target sequence is identical to that of N. gonorrhoeae, whereas other strains have a small number of mismatches within the regions recognized by the primers or probe used in the COBAS AMPLICOR NG test. These cross-reactive strains are occasionally present in urogenital specimens, causing false-positive results in the COBAS AMPLICOR NG test. Analysis of the data generated in a large multicenter clinical trial showed that 2.9% of the specimens gave signals between A(660)s of 0.2 and 3.5 but that one-half of these equivocal specimens did not contain N. gonorrhoeae. Most of these equivocal specimens were correctly classified as true positive or true negative by retesting in duplicate and defining a PCR-positive result as two of three results with an A(660) of > or =2.0. If specimens had been classified as positive or negative based on a single test result using a cutoff of an A(660) of 0.2, specificity would have ranged from 96.2 to 98.9% depending on specimen type, sex, and presence of symptoms. By employing the equivocal zone-retesting algorithm, specificity increased to 98.6 to 99.9% with little effect (0.1 to 4.9% decrease) on sensitivity in most specimen types, enabling the test to achieve a positive predictive value of at least 90% in populations with a prevalence of 4% or higher. In lower-prevalence populations, the test could be used to screen for presumptive infections that would have to be confirmed by an independent test.

White Matter Injury and General Movements in High-Risk Preterm Infants

BACKGROUND AND PURPOSE

Very preterm infants (birth weight, <1500 g) are at increased risk of cognitive and motor impairment, including cerebral palsy. These adverse neurodevelopmental outcomes are associated with white matter abnormalities on MR imaging at term-equivalent age. Cerebral palsy has been predicted by analysis of spontaneous movements in the infant termed "General Movement Assessment." The goal of this study was to determine the utility of General Movement Assessment in predicting adverse cognitive, language, and motor outcomes in very preterm infants and to identify brain imaging markers associated with both adverse outcomes and aberrant general movements.

MATERIALS AND METHODS

In this prospective study of 47 preterm infants of 24-30 weeks' gestation, brain MR imaging was performed at term-equivalent age. Infants underwent T1- and T2-weighted imaging for volumetric analysis and DTI. General movements were assessed at 10-15 weeks' postterm age, and neurodevelopmental outcomes were evaluated at 2 years by using the Bayley Scales of Infant and Toddler Development III.

RESULTS

Nine infants had aberrant general movements and were more likely to have adverse neurodevelopmental outcomes, compared with infants with normal movements. In infants with aberrant movements, Tract-Based Spatial Statistics analysis identified significantly lower fractional anisotropy in widespread white matter tracts, including the corpus callosum, inferior longitudinal and fronto-occipital fasciculi, internal capsule, and optic radiation. The subset of infants having both aberrant movements and abnormal neurodevelopmental outcomes in cognitive, language, and motor skills had significantly lower fractional anisotropy in specific brain regions.

CONCLUSIONS

Aberrant general movements at 10-15 weeks' postterm are associated with adverse neurodevelopmental outcomes and specific white matter microstructure abnormalities for cognitive, language, and motor delays.

An interdisciplinary initiative to reduce unplanned extubations in pediatric critical care units

OBJECTIVE

Unplanned extubations in pediatric critical care units can result in increased mortality, morbidity, and length of stay. We sought to reduce the incidence of these events by reliably measuring occurrences and instituting a series of coordinated interdisciplinary interventions.

METHODS

This was an internal review board-approved quality improvement project. Data were prospectively collected from the electronic medical record, and analyzed over 24 months (January 1, 2009-December 2010), and divided into 3 periods: baseline (9 months), intervention with multiple rapid improvement cycles (8 months), and postintervention (7 months). Interventions included standardization of endotracheal tube taping practices upon admission, improved patient handoffs, systematic review of unplanned events, reexamination of sedation practices, and promotion of transparency of performance measures.

RESULTS

The PICU experienced 21 events in the 9 months before the initiative, 13 events over the 8-month intervention period, and 5 events in the 7-month postintervention period. The cardiac intensive care unit (CICU) experienced 11, 4, and 0 events, respectively. Mean event rates per 100 patient days for each interval were 0.80, 0.50, and 0.29 for the PICU and 0.74, 0.44, and 0 for the CICU. Monthly event rates for the CICU were significantly different by using the Kruskal-Wallis test (P < .05) but not for the PICU (P = .36)

CONCLUSIONS

Through accurate tracking, multiple practice changes, and promoting transparency of efforts and data, an interdisciplinary team reduced the number of unplanned extubations in both ICUs. This reduction has been sustained throughout the postintervention monitoring period.

A historical cross-disciplinary perspective on the professional doctorate in occupational therapy

Clinical doctorates are emerging in occupational therapy. By examining the development of clinical doctorates in medicine, dentistry, psychology, pharmacy, nursing, and physical therapy, implications can be drawn for the future of occupational therapy education. These histories offer us a sense of the distinct purpose and curricular structure of the professional doctorate, its successes and problems, its general sequence of unfolding, the political dynamics surrounding it, and the potential it holds for supporting the profession's capacity for service to patients.

Inter-observer reliability using the General Movement Assessment is influenced by rater experience

OBJECTIVE

To describe the inter-observer reliability of the General Movement Assessment (GMA) among a sample of infants at high-risk of cerebral palsy (CP) among raters with various levels of experience.

METHODS

Video assessments of 150 high-risk infants at 10-15 weeks corrected age were rated by three Prechtl GMA-certified observers with varied experience using the assessment. Videos were scored based on temporal organization of fidgety movements (FMs), presence of abnormal FMs, or absence of FMs. Inter-observer agreements were analyzed with Gwet's AC1 statistic.

RESULTS

We found fair to moderate agreement when subcategories of normal FMs (continuous and intermittent) were included (AC₁ = 0.32-0.57) and moderate to near perfect agreement when normal categories of FMs were combined (AC₁ = 0.60-0.95). Reliability was higher among observers with more experience using the GMA (AC₁ = 0.57-0.98) than the observer with less experience (AC₁ = 0.32-0.61).

CONCLUSIONS

Caution may be warranted when the GMA is used to differentiate "continuous and intermittent" FMs temporal organization. The GMA is highly reliable among experienced raters when comparing normal FMs to other FMs categorizations.