Analytical sensitivity of four commonly used hCG point of care devices

Dose safety and pharmacodynamics of subcutaneous bupivacaine in a novel extended-release microparticle formulation: A phase 1, dose-ascending study in male volunteers

A novel microparticle-based extended-release local anaesthetic containing a bupivacaine/poly-lactic-co-glycolic acid (PLGA; LIQ865A) or plain bupivacaine (LIQ865B) was examined in a first-in-human trial. The objectives were to examine the dose safety/tolerability and pharmacodynamics. Randomized subcutaneous injections of LIQ865A (n = 16) or LIQ865B (n = 12) and diluent, contralaterally, were administered in a dose-ascending manner (150- to 600-mg bupivacaine). Subjects were admitted 24 h post-injection and followed for 30 days post-injection. The risk ratios (RRs; 95% CI) of erythematous reactions for LIQ865A versus diluent was 9.00 (1.81-52.23; P = 0.006) and for LIQ865B versus diluent 2.50 (0.69-9.94; P = 0.37). The RR for the development of hematomas (LIQ865A versus diluent) were 3.25 (1.52-8.16; P = 0.004) and 4.00 (0.72-24.89; P = 0.32) (LIQ865B versus diluent). Subcutaneous indurations persisting for 4-13 weeks were seen in 6/16 subjects receiving LIQ865A. One subject receiving LIQ865A (600-mg bupivacaine) developed intermittent central nervous system (CNS) symptoms of local anaesthetic systemic toxicity (85 min to 51 h post-injection) coinciding with plasma peak bupivacaine concentrations (490-533 ng/ml). Both LIQ865 formulations demonstrated dose-dependent hypoesthesia and hypoalgesia. The duration of analgesia ranged between 37 and 86 h. The overall number of local adverse events, however, prohibits clinical application without further pharmacological modifications.

Preventing Teen Pregnancies on Teratogenic Drugs by Quality Improvement and Behavioral Economics

BACKGROUND

Adolescents with chronic disease engage in sexual activity similar to their healthy peers, with generally low utilization of contraception. Adolescents with rheumatic diseases prescribed teratogenic medications may be at risk for unplanned pregnancy.

METHODS

Using structured quality improvement (QI) methods with behavior economic (BE) principles, a multidisciplinary team aimed to implement pregnancy prevention processes for females on high-risk medications. We leveraged BE-inspired interventions including improved accessibility of consents, utilizing distinctly colored consent forms, real-time reminders, peer comparison, and audit and feedback. Our primary aim was to increase the number of days between pregnancies for postmenarcheal females followed in rheumatology clinics who were taking teratogenic medications. Phase 1 focused on annual consenting of female adolescents prescribed teratogenic drugs. Phase 2 emphasized sexual history screening and pregnancy prevention planning at every clinic visit for females ≥12 years on teratogenic medications.

RESULTS

We increased the days between pregnancies for female adolescents prescribed teratogenic medications from 52 days to >900 days by using QI methodology with BE strategies. In phase 1, annual consents for postmenarcheal patients on teratogenic medications improved from 0% in 2017 to 95% in 2021. In phase 2, sexual history screening and pregnancy prevention planning at every clinic visit improved from 2% in 2019 to over 78% in 2021.

CONCLUSIONS

A multiphase, multidisciplinary QI project with integration of behavior economic strategies can improve patient and caregiver counseling to prevent unplanned pregnancies for adolescents on teratogenic medications.

Optimization of Patient Management in the Gynecology Emergency Department Using Point-of-Care Beta hCG

Background: Point-of-care testing (POCT) provides shorter turn-around times and, in many cases, potentially improves medical decision making. The AQT90 FLEX® benchtop immunoanalyzer (Radiometer Medical ApS, Copenhagen, Denmark) allows for the determination of beta-human chorionic gonadotropin (βhCG) in 18 min. The main aim of this study was to evaluate the impact of measuring βhCG using the AQT90 analyzer in the gynecology emergency department (ED) compared to the standard practice of using central laboratory blood testing on the patient length of stay (LOS). Methods: The evaluation consisted of two parts. The first one, conducted in the central laboratory, focused on the analytical performances of the AQT βhCG assay. The second one, conducted in the ED, aimed at determining the impact of POCT βhCG implementation on the timeframe in which ED patients require βhCG assessment. Results: The within-lab imprecisions at the mean values of 17 and 287 IU/L were 2.7% and 3.7%, respectively. Using Deming regression (n = 60), the following equation was obtained in the central lab: AQT90 βhCG = 1.1 Roche βhCG—12.9 (r = 0.997). The implementation of POCT βhCG in the ED significantly reduced patient LOS (145 (90−212) min vs. 205 (155−265) with and without AQT90, respectively, p < 0.001). At the 2 IU/L decision level, a 99.7% agreement with the Roche assay was reported (kappa statistics, 0.99). Conclusions: We confirm that the analytical qualities of the AQT 90 were in line with those obtained in the central lab. The implementation of the POCT βhCG is associated with a shorter LOS in the ED due to the faster availability of the results and the faster decision-making possibilities.

False negative point-of-care urine pregnancy tests in an urban academic emergency department: a retrospective cohort study

STUDY OBJECTIVE

To determine the prevalence of false negative point-of-care (POC) urine pregnancy tests among emergency department (ED) patients and among those with abdominal pain or vaginal bleeding.

METHODS

We identified all female patients, ages 14-50 years without prior hysterectomy who had a negative POC urine pregnancy test (beta subunit of human chorionic gonadotropin [β-hCG]) performed by trained clinical staff in the ED between September 1, 2017 and December 31, 2018, as well as a subgroup we defined a priori as "high risk" for early pregnancy complications based on a triage chief complaint (text) of abdominal pain or vaginal bleeding. We identified those with a positive urine β-hCG, serum β-hCG >5 mIU/mL, or a diagnosis of pregnancy within 3 months of the initial ED visit (index visit). We used structured chart review with American College of Obstetrics and Gynecology guidelines to determine pregnancy diagnosis and outcomes (ectopic, intrauterine, abnormal including spontaneous abortion, and unknown), the date of conception, and whether the pregnancy was present at the index visit.

RESULTS

Of 10,924 visits with a negative urine pregnancy test result that were screened for a pregnancy outcome, 171 (1.6%, 95% confidence interval [CI] = 1.4, 1.8) had a pregnancy present at the index visit. Diagnoses were ectopic (n = 12, 7.0%), intrauterine (n = 71, 41.5%), abnormal (n = 77, 45.0%), and unknown (n = 11, 6.4%). Of the 2732 patients with high-risk complaints, 97 (3.6%, 95% CI = 2.9, 4.3) had a pregnancy present at the index visit (relative risk of a pregnancy diagnosis 3.9, 95% CI = 2.9,5.3), including 10/12 ectopic (83%), 58/77 abnormal (75%), and 25/71 intrauterine pregnancies (35%). Serum β-hCG ranged from 2 mIU/mL to above assay (median = 119.5, interquartile range = 957.5).

CONCLUSION

Although false negative urine pregnancy tests were uncommon, multiple pregnancy diagnoses were missed, including ectopic pregnancies. False negatives were more common among patients with abdominal pain or vaginal bleeding. Concurrent serum β-hCG levels demonstrated a broad distribution.

Current Status of Clinical Application of Point-of-Care Testing

CONTEXT.—

The clinical applications of point-of-care testing (POCT) are gradually increasing in many health care systems. Recently, POCT devices using molecular genetic method techniques have been developed. We need to examine clinical pathways to see where POCT can be applied to improve them.

OBJECTIVE.—

To introduce up-to-date POCT items and equipment and to provide the content that should be prepared for clinical application of POCT.

DATA SOURCES.—

Literature review based on PubMed searches containing the terms point-of-care testing, clinical chemistry, diagnostic hematology, and clinical microbiology.

CONCLUSIONS.—

If medical resources are limited, POCT can help clinicians make quick medical decisions. As POCT technology improves and menus expand, areas where POCT can be applied will also increase. We need to understand the limitations of POCT so that it can be optimally used to improve patient management.

A Case of a False-Positive Urine Pregnancy Test and Delayed Diagnosis of Obstructive Pyelonephritis

Patient: Female, 28-year-old

Final Diagnosis: Obstructive pyelonephritis

Symptoms: Dysuria • epigastric pain • flank pain

Medication: —

Clinical Procedure: —

Specialty: General and Internal Medicine

False-Negative Urine Human Chorionic Gonadotropin Testing in the Clinical Laboratory

BACKGROUND

Human chorionic gonadotropin (hCG) assays are used to detect pregnancy, and urine point-of-care tests are frequently used to triage patients. Under certain conditions, urine tests can fail to detect pregnancy, which can have serious consequences for patient management.

OBJECTIVES

To understand the prevalence of different factors contributing to false-negative urinary hCG testing results at our institution.

METHODS

Clinical data for patients with negative urine hCG results and subsequent positive or equivocal serum hCG results within a 1-year period were reviewed.

RESULTS

Out of 9447 negative urine hCG results, 11 potential missed diagnoses were identified, with early gestational age as the most common factor, followed by β-core hook effects.

CONCLUSIONS

Although false-negative urine hCG test results are rare, understanding the commonly encountered reasons for inaccurate testing results can help clinical centers develop strategies to minimize risk for patients.

Accuracy of a point-of-care test for quantifying human chorionic gonadotrophin (hCG) in the management of pregnancy of unknown location in an abortion service

INTRODUCTION

Women may seek abortion at gestations when there is no visible intrauterine pregnancy on ultrasound scanning. Clinical protocols for pregnancy of unknown location (PUL) require measurement of serum human chorionic gonadotrophin (hCG), with the National Institute for Health and Care Excellence recommending that values above 1500 IU/L be further investigated to exclude ectopic pregnancy. Our aim was to determine whether a point-of-care test (POCT) could be used instead of laboratory serum hCG measurement.

METHODS

Over 12 months, women who presented to an abortion service with a PUL had a POCT for blood or urine hCG and laboratory serum hCG measurement. The POCT machine used provides a discrete hCG value below 1000 IU/L and above this gives results as a range. The sensitivity and specificity of the POCT in identifying cases where laboratory serum hCG results were above 1500 IU/L were calculated.

RESULTS

A total of 118 women presented with a PUL, of whom 70 had a POCT on blood (n=49) or urine (n=21) and a corresponding laboratory serum hCG. The sensitivity of the blood POCT was 0.67 (95% CI 0.38 to 0.87) and the specificity was 0.97 (95% CI 0.83 to 0.99). The sensitivity of the urine POCT was 0.25 (CI 0.01 to 0.78) and the specificity was 0.94 (CI 0.69 to 0.99).

CONCLUSION

Although both the blood and urine POCTs had a high level of specificity, neither test was acceptably sensitive. While promising, this POCT for hCG is not sufficiently reliable to replace laboratory serum hCG testing in the management of women with PUL in an abortion service.

Emergency Medicine Myths: Ectopic Pregnancy Evaluation, Risk Factors, and Presentation

BACKGROUND

Ectopic pregnancy (EP) is an important cause of morbidity and mortality in females of reproductive age. Proper diagnosis and treatment are critical, as complications such as rupture, hemorrhagic shock, and even death can occur.

OBJECTIVE

EP is a condition emergency physicians are trained to detect, yet there are multiple myths concerning its evaluation and diagnosis. This article reviews several of these myths in order to improve emergency department (ED) evaluation and diagnosis.

DISCUSSION

EP is a difficult diagnosis and may be missed on initial ED visit. While the diagnosis is often delayed simply due to very early presentations, it can also be missed because patients may not have all the same risk factors or demonstrate the same symptoms. They may also not demonstrate the same serum B-human chorionic gonadotropin levels and trends or have the same ultrasound findings at equivalent gestational ages. Some patients with early EP may have positive ultrasound findings with serum β-hCG levels under a defined discriminatory zone (DZ). On the other hand, some patients with an early viable intrauterine pregnancy may have no visible findings on initial ultrasound, but have serum β-hCG (quantitative) levels well above the DZ. Although rare, EP has even been demonstrated in women with negative urine β-hCG tests or low serum β-hCG levels.

CONCLUSIONS

While EP may be a challenging diagnosis, understanding the myths surrounding EP may help emergency physicians consider it, even when patient risk factors, symptoms, or ED laboratory or imaging studies do not initially or easily define the diagnosis.

Advances in human chorionic gonadotropin detection technologies: a review

Human chorionic gonadotropin (HCG) is a glycoprotein secreted by placental trophoblast cells in pregnancy. HCG is a heterodimer composed of two different α- and β-subunits, with the latter being unique to HCG. As well as being the most important diagnostic markers for pregnancy, HCG is also a tumor marker, therefore, quantitative detection of HCG is of great value. Numerous advanced technologies have been developed for HCG concentration detection including electrochemical immunoassay, chemiluminescent immunoassay, fluorescence immunoassay, resonance scattering spectrometry, atomic emission spectrometry, radioimmunoassay, MS and so on. Some have pursued simple and easy operation, while others have emphasized on accuracy and applications in clinical medicine. This review provides a comprehensive summary of various methods of detecting HCG.

Pathology consultation on human chorionic gonadotropin testing for pregnancy assessment

OBJECTIVES

To provide clarity on the use of qualitative and quantitative human chorionic gonadotropin (hCG) tests for the assessment of pregnancy.

METHODS

A case scenario and a brief review of the relevant literature describing clinical and analytical considerations regarding hCG testing are presented.

RESULTS

In pregnancy, hCG is nearly always detectable in serum and urine within 16 days after ovulation. Serial hCG testing is valuable in the evaluation of suspected ectopic pregnancy. hCG assays vary in their analytical specificity, and qualitative tests may be less analytically sensitive than claimed. Erroneous hCG test results can occur for several reasons.

CONCLUSIONS

hCG assays are reliable diagnostic tests for pregnancy assessment, but a clear understanding of their limitations is necessary for appropriate result interpretation.