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Many of the unique health issues facing women are related to reproductive health and pregnancy. However, several conditions that affect both sexes have distinct manifestations in women including cardiovascular disease, osteoporosis, and anemia. The extent of the effect that the physiological differences between men and women have on the natural course of these diseases and the validity of applying a standard treatment to both genders has not been fully explored. Historically, medical research has largely excluded women, rendering the application of evidence-based medicine to women's health issues somewhat of a misnomer. While most research in women's health originates from developed nations, consideration must be given to women in all regions of the world. Compared to women in developed nations, women in resource-poor countries are burdened with increased morbidity and mortality from gender-related health issues. In order to globally advance women's health, the physiologic and social differences between men and women must be more clearly characterized and these differences must be taken into consideration when designing research endeavors and developing health policy. [ABSTRACT FROM AUTHOR]

Abstract: The identification of cell-free fetal DNA (cffDNA) in maternal circulation has made non-invasive prenatal testing (NIPT) possible. Maternal plasma cell free DNA is a mixture of maternal and fetal DNA, of which, fetal DNA represents a minor population in maternal plasma. Therefore, methods with high sensitivity and precision are required to detect and differentiate fetal DNA from the large background of maternal DNA. In recent years, technical advances in the molecular analysis of fetal DNA (e.g., digital PCR and massively parallel sequencing (MPS)) has enabled the successful implementation of noninvasive testing into clinical practice, such as fetal sex assessment, RhD genotyping, and fetal chromosomal aneuploidy detection. With the ability to decipher the entire fetal genome from maternal plasma DNA, we foresee that an increased number of non-invasive prenatal tests will be available for detecting many single-gene disorders in the near future. This review briefly summarizes the technical aspects of the NIPT and application of NIPT in clinical practice. [Copyright &y& Elsevier]

Point-of-care (POC) testing for the detection of pregnancy and the prediction of ovulation has grown and evolved since the introduction of the first qualitative pregnancy test marketed directly to the consumer over three decades ago. Numerous publications have analyzed both pregnancy and ovulation prediction devices for their sensitivity, accuracy and general utility. Despite vast improvements in ease-of-use and sensitivity from their earlier forms, the primary literature regarding the utility of these devices is at times incomplete. This article reviews the literature focusing on the sensitivity and accuracy of the modern urine-luteinizing hormone ovulation prediction devices, and the effect these devices have on fertility rates. In addition, the analytical sensitivity and clinical utility of POC pregnancy tests will be reviewed, along with the potential causes of false negative and false positive results. Clin Chem Lab Med 2010;48:935–42. [ABSTRACT FROM AUTHOR]

Objectives This case report investigates the origin of a false positive result on a serum qualitative human chorionic gonadotropin (hCG) device. Patient and methods A 46-year-old woman diagnosed with chronic myeloid leukemia presented with nausea and vomiting. A qualitative serum hCG test was interpreted as positive; however, a quantitative serum hCG test was negative (< 5 IU/L). To further investigate this discrepancy, the sample was pretreated with heterophilic blocking reagent (HBR). Additionally, the sample was tested on other qualitative hCG devices composed of antibodies from different animal sources. Blocking reagent from an automated quantitative immunoassay was also tested for its ability to inhibit the heterophile antibody interference. Results The qualitative test result was negative after pretreatment with heterophilic blocking reagent. Other devices composed of antibodies from different animal sources also demonstrated mixed results with the patient's sample. Blocking reagent obtained from the automated quantitative assay inhibited the heterophile antibody interference in the patient's sample. Conclusion This case demonstrates that positive serum point-of-care hCG results should be interpreted with caution and confirmed with a quantitative serum hCG immunoassay when clinical suspicion is raised. [ABSTRACT FROM AUTHOR]

Abstract: Respiratory distress syndrome of the newborn infant caused by immaturity of the fetal lung continues to be a clinical problem. Measurement of pulmonary surfactant production is the most effective way to evaluate pulmonary maturity. Since the first fetal lung maturity test was described more than two decades ago, advances in methodology have produced diagnostically sensitive tests that are both rapid and precise. Unfortunately, currently available tests continue to demonstrate low diagnostic specificity and remain poor predictors of fetal lung immaturity. We review the background, methodology, pre-analytical and analytical concerns, and clinical performance of various fetal lung maturity assays, and discuss the appropriate use and interpretation of these tests. [Copyright &y& Elsevier]

A letter to the editor is presented regarding studies on the clinical use of lamellar body counts (LBC) method for evaluation of fetal lung maturity (FLM).

A letter to the editor is presented in response to the article "The transferrin/log (ferritin) ratio: a new tool for the diagnosis of iron deficiency anemia," by Castel and colleagues in the August 2012 issue.

Quantity not sufficient (QNS) specimens with minimal blood volume for testing are common in clinical laboratories. However, there is no universal definition of minimum volume for a QNS specimen and little data is available addressing the impact of QNS / low volume specimens on turnaround time (TAT) and sample hemolysis. We compared the TAT and hemolysis index from samples ≤1.0 mL to all specimens received and quantified the number of specimens with reduced blood volume. A new QNS policy requiring ≥1.5 mL of sample in a blood tube for laboratory analysis was implemented and the results were assessed by sample hemolysis and TAT. The median laboratory TAT for samples with ≤1.0 mL of blood was 61 min (Interquartile Range, IQR: 50–82), in contrast to 28 min (26–34) for all samples. The hemolysis index for samples ≤1.0 mL was 112 (65–253) and 15 (8–29) for all samples. Requirement of a minimum volume of 1.5 mL of blood resulted in the proportion of samples with TAT ≥ 60 min to decrease from 10.4% to 4.24% in the ED, and for specimens cancelled due to hemolysis to decrease from 4.24% to 3.38%. This policy was introduced hospital wide with similar effects. Together, we correlate limited specimen volume with an increase in laboratory TAT and hemolysis. Implementation of a QNS policy of ≥1.5 mL and provider education provided a significant and durable reduction in TAT and specimen hemolysis. [ABSTRACT FROM AUTHOR]

Background Ethical considerations are increasingly important in medicine. We aimed to determine the mode and extent of teaching of ethics in training programs in clinical chemistry and laboratory medicine. Methods We developed an on-line survey of teaching in areas of ethics relevant to laboratory medicine. Reponses were invited from directors of training programs who were recruited via email to leaders of national organizations. Results The survey was completed by 80 directors from 24 countries who directed 113 programs. The largest numbers of respondents directed postdoctoral training of scientists (42%) or physicians (33%), post-masters degree programs (33%), and PhD programs (29%). Most programs (82%) were 2 years or longer in duration. Formal training was offered in research ethics by 39%, medical ethics by 31%, professional ethics by 24% and business ethics by 9%. The number of reported hours of formal training varied widely, e.g., from 0 to > 15 h/year for research ethics and from 0 to > 15 h for medical ethics. Ethics training was required and/or tested in 75% of programs that offered training. A majority (54%) of respondents reported plans to add or enhance training in ethics; many indicated a desire for online resources related to ethics, especially resources with self-assessment tools. Conclusion Formal teaching of ethics is absent from many training programs in clinical chemistry and laboratory medicine, with heterogeneity in the extent and methods of ethics training among the programs that provide the training. A perceived need exists for online training tools, especially tools with self-assessment components. [ABSTRACT FROM AUTHOR]

Abstract: Discovery of circulating miRNAs in maternal blood has not only facilitated the understanding of their role in normal pregnancy, but also paved new avenues for biomarker discovery to detect pregnancy-associated complications, such as preeclampsia, ectopic pregnancy, gestational diabetes mellitus, fetal growth restriction, recurrent pregnancy loss, and preterm delivery. In this review, we summarize the studies to date of miRNAs in maternal circulation and placental tissue in human. This brief review does not cover all aspects of this intriguing field but focuses on some new and interesting findings of diagnostic potential for miRNAs as biomarkers for pregnancy-specific diseases. [Copyright &y& Elsevier]

Abstract: Background: The Siemens Immulite hCG assay detects all major hCG variants in serum. Currently, this assay is only FDA approved for qualitative measurement of hCG in urine. Methods: Complete validation of the hCG assay in urine was performed on the Siemens Immulite 1000 immunoassay platform. Reference intervals were established for females <55y, females ≥55y, and males 20–70y. Results: The limit of quantitation was 2.0IU/l. The Immulite hCG assay was precise for measuring hCG in urine from pregnant patients with intra- and inter-assay imprecision of <11% CV. The assay was linear over a dynamic range of 2–2600IU/l and 2–3500IU/l for hCG and hCGβ respectively. The assay was non-linear for hCGβcf. No hook effect was observed at concentrations up to 1,200,000pmol/l, for hCGβ or hCGβcf. The reference intervals were <2.0IU/l for males, <2.2IU/l for females <55y, and <12.2IU/l for females ≥55y. Conclusion: The Immulite 1000 hCG assay can accurately quantify hCG in urine. [Copyright &y& Elsevier]

Abstract: Background: Identification of women who will deliver preterm may reduce infant morbidity and mortality. In heterogeneous populations, fetal fibronectin (fFN) and interleukin-6 are excellent predictors of women who will not deliver within two weeks. African-Americans are at higher risk for preterm birth than Caucasians. This study compares the diagnostic utility of fFN and interleukin-6 in cervicovaginal fluid (CVF) to predict preterm birth within 14days of sampling in African-American and Caucasian women. Methods: Interleukin-6 was measured in 667 CVF samples from 580 women with and without symptoms of labor. The utility of CVF interleukin-6 and fFN to predict delivery was determined in the total population and in African-Americans and Caucasians separately. Results: fFN positive (≥50μg/l) results were associated with delivery in ≤14days in African-Americans (Odds Ratios (OR) 8.7; Likelihood Ratio (LR) 3.7) (p <0.0001) and Caucasians (OR 11.9; LR 5.7) (p <0.01). A positive interleukin-6 (≥250ng/l) was associated with delivery in ≤14days in African-Americans (OR 12.7; LR 5.25) (p <0.0001), but not in Caucasians (OR 4.1; LR 3.2) (p =0.13). Conclusions: CVF interleukin-6 and fFN have similar diagnostic utilities in a diverse population. Interleukin-6 more accurately predicts delivery within 14days in African-Americans, while fFN is more accurate in Caucasians. [Copyright &y& Elsevier]

Abstract: Background: Human chorionic gonadotropin (hCG) is a heterodimeric glycoprotein hormone with considerable molecular heterogeneity. There is uncertainty regarding which hCG variants are detected by different hCG assays. The analytical specificity of 8 hCG assays was investigated. Methods: WHO International Reference Reagents for hCG, nicked hCG (hCGn), beta subunit (hCGβ), nicked beta subunit (hCGβn), and beta core fragment (hCGβcf) were individually added to hCG-free human serum. Specimens were analyzed with 8 commercially available hCG assays. Equimolar detection of hCG variants was defined as a recovery of 90–110%. Results: All assays detected hCG and hCGn with mean recoveries of 98.3 and 94.6%, respectively. Seven assays detected hCGβ (mean recovery 103.8%) but with high variation, and equimolar detection was observed only in four. The mean recovery of hCGβn was 85.5% but was highly variable with only two assays showing equimolar detection. With a mean recovery of 53.4%, two assays detected hCGβcf and both underestimated it considerably. Information provided by the assay manufacturer regarding hCG variant analytical specificity was inadequate or unclear in 75% of the assays. Conclusions: hCG assays vary considerably in their ability to detect different hCG variants. Manufacturers of hCG assays should clearly indicate the hCG variant specificity of their reagent systems. [Copyright &y& Elsevier]

Background: Analytical errors in clinical laboratory testing are unavoidable. Recent reports have suggested the idea of “physiological profiling” which uses several results from a given patient to identify clinically unlikely results. The objective of this study was to establish rules-based criteria for identifying physiologically unlikely TSH and free T4 (fT4) results. Methods: For a 30-month period, all samples with fT4 concentrations >2 ng/dl and TSH concentrations >0.1 μIU/ml were investigated. Results: Among 7918 plasma samples for which both TSH and fT4 concentrations were measured, 18 (0.23%) had fT4 and TSH exceeding the investigated limits. Of these, two were due to heterophile antibody interference (with the TSH assay), one was proven to be due to random error, four could be explained by the patients'' conditions, three were from infants <1 week of age, and the remaining eight were unresolved, primarily due to insufficient sample, discarded samples, and inability to obtain patient histories. Conclusions: This study defined a rules-based alert system for clinically unlikely combinations of TSH and fT4 results. This pilot study demonstrates that this system is capable of detecting at least two different types of laboratory errors that would have otherwise gone undetected. [Copyright &y& Elsevier]

Background Plasma concentrations of human chorionic gonadotropin (hCG) have been shown to increase with age due to pituitary secretion. We previously recommended that an hCG cutoff of 14.0 IU/L be used for women ≥ 55 years of age. However, it remains unknown whether concentrations > 14.0 IU/L can be expected in women with advanced age. Our objectives were to establish plasma hCG reference intervals and correlate follicle stimulating hormone (FSH) and hCG concentrations in postmenopausal females ≥ 55 years. Methods Residual plasma samples from 798 women ≥ 55 years were utilized with 303, 269, and 226 samples belonging to the age groups 55–69, 70–84, and ≥ 85 years, respectively. FSH and hCG were measured using the Abbott ARCHITECT. All positive hCG samples (hCG ≥ 5 IU/L) were analyzed for potential heterophile antibody interference and 3 were excluded. Electronic medical records were reviewed and patients with malignancy were excluded. Results 8% (56/666) of women age ≥ 55 years had plasma hCG ≥ 5 IU/L. There were 19, 16, and 21 patients with hCG ≥ 5 IU/L in the age groups 55–69, 70–84, and ≥ 85 years, respectively. The highest hCG concentrations observed in each age group were: 55–69 years maximum = 11.7 IU/L and 97.5th percentile = 9.6 IU/L; 70–84 years maximum = 18.09 IU/L, 97.5th percentile = 6.2 IU/L; ≥ 85 years maximum = 11.1 IU/L and 97.5th percentile = 10.0 IU/L, and the overall 97.5th percentile = 8.5 IU/L for all women ≥ 55 years of age. Neither hCG nor FSH concentrations continued to increase with age in women ≥ 55 years. Conclusions The prevalence of positive hCG in women ≥ 55 years is 8%. This study confirms our previously recommended cutoff of 14 IU/L for women ≥ 55 years of age. In women ≥ 55 years of age, FSH concentrations do not predict hCG concentrations. [ABSTRACT FROM AUTHOR]

Objective Elevated concentrations of hCG beta core fragment (hCGβcf) are known to cause false-negative results in qualitative urine pregnancy test devices, but the pattern of urinary hCGβcf during normal pregnancy has not been well characterized. Here, we evaluate the relationship between urine hCG, hCGβcf, and hCG free β subunit (hCGβ) during pregnancy. Design and methods Banked second trimester urine specimens from 100 pregnant women were screened for high concentrations of hCGβcf using a qualitative point-of-care device known to demonstrate false-negative results in the presence of elevated hCGβcf concentrations. Additional first and third trimester specimens from the same pregnancy were obtained from 10 women who generated negative/faint positive results, 5 women who generated intermediate positive results, and 10 women who generated strong positive results on the point-of-care device. Intact hCG, hCGβcf, hCGβ, and specific gravity were quantified in these 75 specimens. Results Urinary hCGβcf concentrations were greater than intact hCG concentrations at all times. A strong correlation ( r 2 = 0.70) was observed between urine intact hCG and hCGβcf concentrations. A poor correlation was observed between specific gravity and intact hCG ( r 2 = 0.32), hCGβ ( r 2 = 0.32), and hCGβcf ( r 2 = 0.32). The highest hCGβcf concentrations were observed between 10 and 16 weeks gestation but individual women demonstrated very different patterns of hCGβcf excretion. Conclusions Urine specimens with elevated hCGβcf are frequently encountered during pregnancy but hCGβcf excretion patterns are unpredictable. Manufacturers and clinicians must appreciate that hCGβcf is the major immunoreactive component in urine during pregnancy and must design and interpret qualitative urine hCG test results accordingly. [ABSTRACT FROM AUTHOR]

Objective Elevated urine concentrations of hCG beta core fragment (hCGβcf) are known to cause false negative qualitative point-of-care hCG test results, but limited information is available regarding urine hCGβcf. In this study, we evaluate the relationship between serum and urine hCG concentrations and the frequency of elevated urine hCGβcf concentrations. Design and methods Paired serum and urine specimens were obtained from 60 women at various stages of pregnancy and hCG was measured using the Abbott Architect and Roche Cobas e602 assays. Urine specimens with the greatest difference in urine hCG concentrations between these two instruments were tested using a qualitative point-of-care device and hCGβcf was quantified using LC–MS/MS. Results Urine hCG concentrations were lower than serum and the magnitude of the difference depended on whether the hCG assay detected hCGβcf. Elevated hCGβcf concentrations (> 280,000 pmol/L) were observed in 12% of specimens from an unselected patient population. There was a significant correlation (r = 0.97; p < 0.0001) between the difference (Roche hCG–Abbott hCG) and the hCGβcf concentration as measured by LC–MS/MS (Roche–Abbott difference IU/L = (hCGβcf (pmol/L) ∗ 0.131 + 656)). Conclusions A correlation exists between serum and urine hCG concentrations but this correlation is variable. hCGβcf concentrations can be estimated using two automated assay reagent platforms that differ in their recognition of hCGβcf. [ABSTRACT FROM AUTHOR]

Background The ability to perform quantitative hCG testing in whole blood at the point-of-care is desirable. The purpose of this study was to perform an analytical validation of the Abbott i-STAT Total β-hCG test. Methods Whole blood, plasma, and serum samples were prepared by the addition of hCG and were used to evaluate precision, linearity, analytical sensitivity, accuracy, the high-dose hook effect, and dilution recovery. Results Imprecision was highest with whole blood (CV = 16.0% and 6.7% at 10 and 1184 IU/l, respectively) and lowest in serum (CV = 8.1% and 4.3% at 11 and 1305 IU/l, respectively). The limits-of-quantitation were 8 and < 5 IU/l for whole blood and both plasma and serum, respectively. The assay was linear between 5 and 2000 IU/l in all sample types (R 2 ≥ 0.998). i-STAT results agreed most closely with the Architect Total β-hCG assay and with greater differences observed with Beckman DxI Total βhCG and Roche Cobas e601 hCG+β assays (mean differences across all sample types were 9.3% and 12.3%, respectively). A high-dose hook effect was observed at concentrations > 400,000 IU/l. Accuracy was achieved in samples diluted with serum but not saline. Conclusions The i-STAT Total β-hCG test demonstrates acceptable performance for quantifying hCG in whole blood, plasma and serum. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Measurement of human chorionic gonadotropin (hCG) and α-fetoprotein (AFP) in cerebrospinal fluid (CSF) can aid in the diagnosis of germ cell tumors (GCTs). Matrix effects can influence test results when alternative sample types are used, therefore, alternative sample types should always be validated before clinical use. Here we have validated the Advia® Centaur total hCG and AFP methods for use with CSF. We also performed a retrospective review of 5years of CSF hCG and AFP measurements sent out from our institution. Design and methods: Both hCG and AFP concentrations were measured using the ADVIA Centaur® total hCG or AFP assay. Results: The Centaur hCG and AFP assays, performed on CSF, had intra- and inter-assay imprecisions <10.2% CV. The assays were linear over a dynamic range of 10–1000IU/L for hCG and 10–1000μg/L for AFP. Retrospective chart review confirmed that GCTs have a male predominance and are diagnosed most frequently in the second decade of life. The data also illustrate the importance of measuring both serum and CSF concentrations as CSF can be elevated in the absence of serum elevations. Conclusions: The Centaur total hCG and AFP methods accurately quantify hCG and AFP in CSF. [Copyright &y& Elsevier]

Abstract: Objectives: To design a predictive model for assessing the risk of developing respiratory distress syndrome (RDS) using gestational age (GA) and lamellar body counts (LBC). Design and methods: LBCs and patient outcome data was obtained from five medical centers. A total of 223 patients were included in this study; 19 gave birth to infants that developed RDS, 204 gave birth to infants that were unaffected. The absolute risk and odds ratios of an infant developing RDS as a function of GA and LBC were calculated. Logistic analysis was used to model the odds of RDS as a function of GA and LBC. Results: The odds of RDS decreased for each increasing week of GA and decreased with increase in the LBC. GA-specific LBC cutoffs are provided for sensitivities between 84 and 100%. The bias adjusted area under the ROC curve for the classification of RDS, based on GA and LBC, was 0.906 using the logistic model and 0.746 using a single cutoff of LBC (50,000/μL) to classify immaturity. Conclusions: GA-specific risk assessment and GA-specific cutoffs provide increased sensitivity and specificity in the evaluation of fetal lung maturity. [Copyright &y& Elsevier]

Physicians are urged to communicate more openly following medical errors, but little is known about pathologists' attitudes about reporting errors to their institution and disclosing them to patients. We undertook a survey to characterize pathologists' and laboratory medical directors' attitudes and experience regarding the communication of errors with hospitals, treating physicians, and affected patients. We invited 260 practicing pathologists and 81 academic hospital laboratory medical directors to participate in a self-administered survey. This survey included questions regarding estimated error rates and barriers to and experience with error disclosure. The majority of respondents (~95%) reported having been involved with an error, and respondents expressed near unanimous belief that errors should be disclosed to hospitals, colleagues, and patients; however, only about 48% thought that current error reporting systems were adequate. In addition, pathologists expressed discomfort with their communication skills in regard to error disclosure. Improving error reporting systems and developing robust disclosure training could help prevent future errors, improving patient safety and trust. [ABSTRACT FROM AUTHOR]

Abstract: Background: The surfactant/albumin ratio is a popular fetal lung maturity (FLM) test that will be unavailable in the near future. We conducted surveys of obstetricians and clinical laboratorians to assess FLM testing trends from the perspectives of both disciplines and to identify how both communities might adapt to the loss of the surfactant/albumin ratio. Methods: 2067 physicians were surveyed about their familiarity with and clinical utility of various FLM tests. 6137 laboratorians were surveyed about their FLM test menu and volumes. Results: Twenty-five percent of physicians indicated a decrease in FLM test ordering and the frequency of FLM testing has decreased significantly (p=0.011) since 1998. The surfactant/albumin ratio is the most frequently offered FLM test and was the test of choice for 62% of physicians. Without the surfactant/albumin ratio, 68% of physicians would order the lecithin/sphingomyelin ratio and 44% would order the lamellar body count (LBC) which were offered by 18 and 13% of laboratories, respectively. 16% of laboratories were planning to offer the LBC within 24months. Conclusions: FLM testing is decreasing. The loss of the surfactant/albumin ratio will increase the demand for the lecithin/sphingomyelin ratio and the LBC, yet few laboratories offer either test and most are not planning to offer the LBC. [ABSTRACT FROM AUTHOR]

The lamellar body count (LBC) represents an alternative method to the TDx-FLM II (Abbott Laboratories, Abbott Park, IL), which is planned to be discontinued, for assessing fetal lung maturity. Our objective was to validate the LBC on 3 hematology analyzers (Coulter LH 750 and Coulter Ac·T diff2, Beckman Coulter, Brea, CA; and Sysmex XE-2100, Sysmex, Mundelein, IL) to serve as a template for other laboratories attempting to perform in-house validation. Intra-assay and interassay coefficients of variation ranged from 1.7% to 21.8% and 1.9% to 7.1%, respectively, and all analyzers demonstrated excellent linearity. Whole blood and meconium were shown to interfere with LBCs, and specimens with these contaminants should be tested using phosphatidyl glycerol. With a TDx-FLM II cutoff of 55 mg/g or more and an LBC cutoff of 50,000/µL or more for maturity, concordance between the TDx-FLM II and the LBC on all instruments was poor (<80% in all cases). Concordance between hematology analyzers was excellent ( ≥94%). When laboratories are performing in-house validations, they should not correlate LBC with TDx-FLM II results without outcome data. Correlation with another validated LBC method is preferred. [ABSTRACT FROM AUTHOR]

Abstract: Background: Qualitative point-of-care (POC) tests for human chorionic gonadotropin (hCG) vary in their ability to detect purified hCG variants and there is data to suggest that over-the-counter (OTC) devices might also display similar variability. This could potentially influence the detection of urine hCG in early pregnancy. Methods: Six OTC devices were tested for their ability to detect 5 hCG variants. Ten early pregnancy urine specimens were selected for their diverse expression of hCG variants. The samples were tested with 6 brands of POC and 6 OTC devices. Results: OTC devices consistently recognized intact hCG, hCGn, and hCGβ. hCGβn was consistently recognized by 4 out of 6 brands. One brand inconsistently recognized hCGβcf. OTC and POC devices varied greatly in their ability to detect hCG in early pregnancy urine, despite the fact that urine samples were adjusted to the same intact hCG concentration. Interestingly, we found that the OTC devices had better analytical sensitivity than the POC devices. Clinitest® and First Response® demonstrated the lowest hCG detection limits for POC and OTC devices, respectively. Conclusions: Both OTC and POC devices are capable of detecting hCG concentrations in early pregnancy urine, and OTC devices demonstrated better analytical sensitivity relative to POC devices. [Copyright &y& Elsevier]

Objective Previous work has documented the ability of the Clearblue Advanced Test with Weeks Estimator, a new over-the-counter (OTC) urine hCG device, to accurately estimate weeks since ovulation in early pregnancy. In this study, the performance of this device in more advanced pregnancy was assessed. Methods The Clearblue Advanced Test with Weeks Estimator device was used to test solutions containing purified intact hCG and hCGβcf at concentrations consistent with early, middle and late pregnancy. Urine samples from three normal pregnant patients 9–13 weeks of gestation and from a patient 12 weeks of gestation known to generate false negative results on qualitative urine test devices due to excess hCGβcf were also evaluated. Results The Clearblue Weeks Estimator device gave expected results using solutions containing purified intact hCG and hCGβcf at concentrations observed throughout pregnancy. The device generated expected results using urine from three of four patients tested between 9 and 13 weeks of gestation. However, when urine from a patient with elevated concentrations of hCGβcf was used, the device correctly indicated pregnancy although the estimate for the date was incorrect. Conclusion This device gave expected “pregnant” results using all samples tested. However, the “Weeks Estimator” should be interpreted with caution when used by patients after seven weeks of pregnancy. [ABSTRACT FROM AUTHOR]

Abstract: Background: The purpose of this study was to investigate the degree of ΔOD450 method variability and its effect on ΔOD450 measurements between selected clinical laboratories in the U.S. Method: Four amniotic fluid specimens were sent to 7 clinical laboratories in the U.S. for ΔOD450 analysis. In addition, scanning spectrophotometric data from 152 amniotic fluid samples were used to compare ΔOD450 values calculated using both log and linear OD scales. Results: We found that no 2 laboratories used exactly the same method and no laboratory used precisely the same method as originally described by Liley. Despite the varied methods, the ΔOD450 measurements were remarkably similar. The exception was 1 sample that was subjected to chloroform extraction. The ΔOD450 measurement on this sample was 82% lower than the mean. On average, ΔOD450 results determined from a linear OD scale were 37% lower than those determined from a log scale. Conclusion: Although there is no standard method for performing the ΔOD450, inter-laboratory variation of ΔOD450 results is remarkably small. As our and other previous studies have reported, these data suggest that both chloroform extraction and use of a linear scale have the potential to result in lower ΔOD450 results. [Copyright &y& Elsevier]

Abstract: Background: Ischemia can alter the ability of albumin to bind free metal atoms. Based on these biochemical changes, methods to quantify ischemia modified albumin (IMA) were developed to assist in the evaluation of patients with symptoms of cardiac ischemia. Since ischemia can occur in any vascular bed, the specificity of IMA for cardiac muscle ischemia is unclear and requires further investigation. Methods: We evaluated the specificity of an IMA test in patients with skeletal muscle ischemia during arthroscopic knee surgery. A pressurized thigh cuff was continuously inflated to 300 mm Hg on the operative leg, in order to arrest blood flow during the procedure. Samples were collected before surgery, 15 min after surgery, and prior to discharge. Results: Twenty-three patients were enrolled in the study. Median tourniquet time was 29 min (range 19–108). Median pre-operative IMA was 90.2 KU/l (range 77–101.6). Statistically significant (p <0.05) increases in IMA and myoglobin concentrations, and decreases in albumin concentrations were observed following tourniquet release and before discharge. Conclusions: Post-operative myoglobin elevations indicated that skeletal muscle ischemia was sufficient to produce detectable myocyte necrosis. Post-operative IMA increases are consistent with ischemic modification of albumin during exposure to ischemic conditions in skeletal muscle during and /or immediately after tourniquet application. However, the negative correlations between IMA and albumin results suggest that increases in IMA were in part due to lower post-operative albumin concentrations resulting in decreased cobalt binding. [Copyright &y& Elsevier]

Background: Epstein–Barr virus (EBV) infection is associated with infectious mononucleosis, Burkitt''s lymphoma, and nasopharyngeal carcinoma. Serologic diagnosis of acute EBV infections has been the method of choice, and tests are available as indirect fluorescent antibody (IFA)- and ELISA-based assays. Objective: To evaluate the ELISA-based EBV assay from Wampole Laboratories (Cranbury, NJ). Methods: One hundred fifty-two consecutive samples received for comprehensive EBV serology were analyzed. Results: A comparison of the Wampole Laboratories'' ELISA system with the Gull/Meridian Diagnostics (Cincinnati, OH) IFA, and ELISA assays showed 88% concordance for anti-viral capsid antigen (VCA) IgM (n=177); 79% concordance for anti-VCA IgG (n=177); 87% concordance for anti-NA IgG (n=172); and 48% concordance for anti-EA IgG (n=165). Using the results from all four antibody assays to identify patients with acute infection, the Wampole system had a 67% concordance with the Gull/Meridian (n=164). Conclusions: Differences in the specificity of the anti-EA IgG assays (i.e. reactivity against the D component of early antigen (EA-D) (Wampole) vs. reactivity to EA-D and the R component of early antigen (EA-R) (Gull/Meridian)) may have lead to poor concordance (48%) for this particular assay. Because the Wampole system had a <70% overall concordance with the Gull/Meridian system in diagnosis of acute infection, these data suggest that further studies are needed to determine the true clinical sensitivity and specificity of this system. [Copyright &y& Elsevier]

Abstract: Epstein–Barr virus serologic profiles were obtained from 618 patients using an automated platform, including the new BioPlex heterophile assay. When compared with 2 IgM viral capsid antigen (VCA) assays and a predicate heterophile assay, the BioPlex heterophile assay was more likely to be associated with serologic patterns of acute infection. [Copyright &y& Elsevier]