A clinical 3D pointing test differentiates spatial memory deficits in dementia and bilateral vestibular failure.

BACKGROUND: Deficits in spatial memory, orientation, and navigation are often neglected early signs of cognitive impairment or loss of vestibular function. Real-world navigation tests require complex setups. In contrast, simple pointing at targets in a three-dimensional environment is a basic sensorimotor ability which provides an alternative measure of spatial orientation and memory at bedside. The aim of this study was to test the reliability of a previously established 3D-Real-World Pointing Test (3D-RWPT) in patients with cognitive impairment due to different neurodegenerative disorders, bilateral vestibulopathy, or a combination of both compared to healthy participants. METHODS: The 3D-RWPT was performed using a static array of targets in front of the seated participant before and, as a transformation task, after a 90-degree body rotation around the yaw-axis. Three groups of patients were enrolled: (1) chronic bilateral vestibulopathy (BVP) with normal cognition (n = 32), (2) cognitive impairment with normal vestibular function (n = 28), and (3) combined BVP and cognitive impairment (n = 9). The control group consisted of age-matched participants (HP) without cognitive and vestibular deficits (n = 67). Analyses focused on paradigm-specific mean angular deviation of pointing in the azimuth (horizontal) and polar (vertical) spatial planes, of the preferred pointing strategy (egocentric or allocentric), and the resulting shape configuration of the pointing array relative to the stimulus array. Statistical analysis was performed using age-corrected ANCOVA-testing with Bonferroni correction and correlation analysis using Spearman's rho. RESULTS: Patients with cognitive impairment employed more egocentric pointing strategies while patients with BVP but normal cognition and HP used more world-based solutions (pBonf 5.78 × 10-3**). Differences in pointing accuracy were only found in the azimuth plane, unveiling unique patterns where patients with cognitive impairment showed decreased accuracy in the transformation tasks of the 3D-RWPT (pBonf < 0.001***) while patients with BVP struggled in the post-rotation tasks (pBonf < 0.001***). Overall azimuth pointing performance was still adequate in some patients with BVP but significantly decreased when combined with a cognitive deficit. CONCLUSION: The 3D-RWPT provides a simple and fast measure of spatial orientation and memory. Cognitive impairment often led to a shift from world-based allocentric pointing strategy to an egocentric performance with less azimuth accuracy compared to age-matched controls. This supports the view that cognitive deficits hinder the mental buildup of the stimulus pattern represented as a geometrical form. Vestibular hypofunction negatively affected spatial memory and pointing performance in the azimuth plane. The most severe spatial impairments (angular deviation, figure frame configuration) were found in patients with combined cognitive and vestibular deficits.

Quantitative and qualitative sensory testing results are associated with numbness rather than neuropathic pain in patients with post-implant trigeminal neuropathy: a cross-sectional pilot study.

Purpose: This study aimed to characterize the sensory profile of patients with post-implant trigeminal neuropathy and identify the association between subjective symptoms and objective signs including psychophysical testing and radiographic imaging. This study further evaluated to the association between quantitative sensory testing (QST)/qualitative sensory testing (QualST) and the severity of nerve injury graded by radiographic imaging. Materials and methods: This retrospective study included 34 patients diagnosed with post-implant trigeminal neuropathy. Data on the neuropathic pain symptom inventory (NPSI), thermal and electric QST, bedside QualST, and cone beam computed tomography (CBCT) was collected and the association between these variables were analysed. Results: Numbness was the most common subjective symptom and evoked pain was the most frequent neuropathic pain. There was no significant correlation between negative and positive symptoms. Spearman's rank correlation analyses indicated that objective findings including QST/QualST correlated with a sensory loss profile rather than a gain of function profile. Moderate positive correlations between some positive symptoms and the score of QualST were observed. The Mann-Whitney U test showed that subjective symptoms did not differ according to the severity of nerve damage according to CBCT, but the electric QST and QualST was discriminative. Conclusions: This study suggests that QST/QualST associated with the severity of nerve damage according to CBCT might be useful in assessing numbness in patients with negative and positive symptoms after implant surgery, but may be of marginal utility in the evaluation of neuropathic pain within the limitation of this cross-sectional study with small sample size.

Performance on bedside tests of attention and organized thinking in patients with dementia free from delirium.

ABSTRACTObjectives:Bedside tests of attention and organized thinking were performed in patients with cognitive impairment or dementia but without delirium, to provide estimates of false positive rates for detecting delirium superimposed on dementia (DSD). DESIGN AND SETTING: This cross-sectional study was conducted in outpatients and institutionalized patients without delirium representing a wide spectrum of severity of cognitive impairments. PARTICIPANTS: Patients with dementia or a cognitive disorder according to DSM IV criteria, after exclusion of (suspected) delirium according to DSM IV criteria. MEASUREMENTS: Tests for inattention and disorganized thinking from the CAM-ICU were assessed. RESULTS: The sample included 163 patients (mean age 83 years (SD 6; 64% women)), with Alzheimer's disease as most prevalent (45%) diagnosis and a mean MMSE-score of 16.8 (SD 7.5). False positive rates of the test of attention varied from 0.04 in patients with normal to borderline cognitive function to 0.8 in those with severe dementia. The false positive rate of the test of disorganized thinking was zero in the normal to borderline group, increasing to 0.67 in patients with severe dementia. When combining test results false positive rates decreased to 0.03 in patients with MMSE scores above 9. CONCLUSION: Use of simple bedside tests of attention and organized thinking for the clinical diagnosis of DSD will result in high rates of false positive observations if used regardless of the severity of dementia. However, if test results are combined they may be useful to exclude DSD in patients with minimal to moderate degrees of dementia, but not in the severe group.

Analytical performance of a platform for point-of-care CRP testing in adults consulting for lower respiratory tract infection in primary care.

C-reactive protein (CRP) is a biomarker widely used for disease severity assessment and treatment of inflammatory conditions. Point-of-care testing (POCT) devices should ideally be rapid and provide similar results to standard tests done in laboratories. Two thousand nine hundred twenty-two serum samples were obtained from adult patients presenting to primary care with symptoms of lower respiratory infection in a European diagnostic study. The analytic performance of the CRP QuikRead POCT device (Orion Diagnostica) was evaluated by comparing results with a central laboratory method (Dimension Vista, Siemens), with both tests performed in a laboratory setting. For a CRP cut-off concentration of ≥ 30 mg/L, the QuikRead test had a sensitivity of 92.2%, and specificity of 99.4%. The mean difference between the QuikRead and the central lab test was 0.4 mg/L. The slope of the Passing-Bablok regression was 0.94 (95% CI 0.93-0.95) indicating an underestimation of CRP levels of 6% by QuikRead. CRP estimates obtained from the QuikRead test correlate well with a central laboratory assay and the measurement displays low inter-assay variation. Therefore, the QuikRead test is a good candidate for CRP testing in primary care.

[Vertigo in the Emergency Department: new bedside tests]. / Szédülés vizsgálata a sürgosségi osztályon: új, ágy melletti diagnosztikai eljárások.

According to international statistics, the first examination of 25% of patients with vertigo is carried out in Emergency Departments. The most important task of the examining physician is to diagnose life threatening pathologic processes. One of the most difficult otoneurological diagnostic challange in Emergency Departments is to differentiate between dangerous posterior scale stroke presenting with isolated vertigo and the benign vestibular neuritis.These two disorders can be safely differentiated using fast, non-invasive, evidence based bedside tests which have been introduced in the past few years. 35% of stroke cases mimicking vestibular neuritis (pseudoneuritis) are misdiagnosed at the Emergency Department, and 40% of these cases develop complications. During the first 48 hours, sensitivity for stroke of the new test that is based on the malfunction of the oculomotor system is better than the diffusion-weighted cranial magnetic resonance imaging. Using special test glasses each component of the new test can be made objective and repeatable.

Audit about the knowledge of healthcare personnel regarding transfusion: multicenter study.

INTRODUCTION: Transfusion is an important question of daily clinical practice. Transfusion is governed by rigorous security rules. AIM: To assess the knowledge of healthcare personnel regarding transfusion. METHODS: This descriptive study was carried out by an anonymous survey, with anaesthetist resident, surgery resident, interns, anaesthetist, and nurses. This study was from January 1 to February 29, 2020. It was approved by the local ethics committee. RESULTS: We included 196 participants. 94.9% knew that red blood cells must be stored in the refrigerator. 58.2% thought that red blood cells should be transfused within 30 minutes of warming, and 31.6% said it should be transfused within 3 hours. We found that 85% knew that fresh frozen plasma should be stored in the freeze, and 59.7% said that the frozen plasma should be thawed within 30 minutes at most and 38.3% thought that the thawing should take at least one hour. Regarding the pretransfusion bedside test, 84.4% knew that it must be done by two personnel one of whom must be a doctor. 40.8% thought that the test consists of mix a drop of patient blood and a drop of bag blood. CONCLUSION: Several insufficiencies were found. There is a necessity of launching periodic training courses focusing on the management of blood products and the transfusion procedure.

Current trends in digital camera-based bioassays for point-of-care tests.

Point-of-care and bedside tests are analytical devices suitable for a growing role in the current healthcare system and provide the opportunity to achieve an exact diagnosis by an untrained person and in various conditions and sites where it is necessary. Using a digital camera integrated into a well-accessible device like a smartphone brings a new way in which a colorimetric point-of-care diagnostic test can provide unbiased data. This review summarizes basic facts about the colorimetric point-of-care tests, principles of how to use a portable device with a camera in the assay, applications of digital cameras for the current tests, and new devices described in the recent papers. An overview of the recent literature and a discussion of recent developments and future trends are provided.

The Icepack Test in the Diagnosis of Myasthenia Gravis with Ocular Features: A Systematic Review of Diagnostic Accuracy, Technique, and Economic Utility.

BACKGROUND: The diagnosis of myasthenia gravis (MG) may be challenging and require multiple specialised testing modalities. Accessing these investigations can involve significant waiting time and costs. The bedside icepack test (IPT) has been proposed to assist with the diagnosis of MG with ocular features, and may prove an economically viable; however, there have been there is heterogeneity in the literature evaluating the IPT. OBJECTIVES: A systematic review was performed examining the accuracy, described techniques, and economic implications of the IPT for the diagnosis of MG with ocular features. METHOD: The databases EMBASE, PubMed, and the Cochrane Library were searched from inception to July 2022. The systematic review adhered to PRISMA guidelines. Eligibility determination was undertaken with a standardised form using appropriate inclusion criteria. The Cochrane risk of bias assessment tool for diagnostic test accuracy was employed to evaluate studies that presented the diagnostic performance of the IPT. The Johanna Briggs Institute Critical Appraisal Checklist for Economic Evaluations was used for the assessment of studies presenting economic evaluations of the IPT. RESULTS: 20 articles met the specified criteria and included a total of 1264 participants. The IPT had a sensitivity ranging from 38.5% to 100%. Specificity was found to be > 95% in six studies. Excluding two outlier results of 25% and 31.3%, the lowest specificity recorded was 62.5%. The most commonly described method of evaluating the IPT involved applying ice to both eyelids and using a >2 mm change as a threshold for a positive test (evaluated with a ruler). There were no adverse effects described with the IPT. There were no studies that formally examined the economic implications of the IPT. CONCLUSIONS: The IPT is a well-tolerated and readily available diagnostic tool that has an important role in the evaluation of possible MG with ocular features in specific contexts. Despite limited economic evaluation of this test, it is likely the use of the IPT may result in significant financial and time savings.

Single count breath test for the evaluation of respiratory function in Myasthenia Gravis: A systematic review.

BACKGROUND: Myasthenia gravis (MG) can have a variety of respiratory presentations, ranging from mild symptoms through to respiratory failure. The evaluation of respiratory function in MG can be limited by accessibility to testing facilities, availability of medical equipment, and facial weakness. The single count breath test (SCBT) may be a useful adjunct in the evaluation of respiratory function in MG. METHOD: A systematic review of the databases PubMed, EMBASE, and the Cochrane Library was conducted from inception to October 2022 in accordance with PRISMA guidelines and was registered on PROSPERO. RESULTS: There were 6 studies that fulfilled the inclusion criteria. The described method of evaluating SCBT involves inhaling deeply, then counting at two counts per second, in English or Spanish, sitting upright, with normal vocal register, until another breath needs to be taken. The identified studies support that the SCBT has a moderate correlation with forced vital capacity. These results also support that SCBT can assist the identification of MG exacerbation, including via assessment over the telephone. The included studies support a threshold count of ≥ 25 as consistent with normal respiratory muscle function. Although further analysis is needed, the included studies describe the SCBT as a quick bedside tool that is inexpensive and well tolerated. CONCLUSIONS: The results of this review support the clinical utility of the SCBT in assessing respiratory function in MG and describe the most current and effective methods of administration.

Different approaches to test orientation of self in space: comparison of a 2D pen-and-paper test and a 3D real-world pointing task.

Spatial orientation is based on a complex cortical network with input from multiple sensory systems. It is affected by training, sex and age as well as cultural and psychological factors, resulting in different individual skill levels in healthy subjects. Various neurological disorders can lead to different patterns or specific deficits of spatial orientation and navigation. Accordingly, numerous tests have been proposed to assess these abilities. Here, we compare the results of (1) a validated questionnaire-based self-estimate of orientation/navigation ability (Santa Barbara Sense of Direction Scale, SBSODS) and (2) a validated pen-and-paper two-dimensional perspective test (Perspective Taking Spatial Orientation Test, SOT) with (3) a newly developed test of finger-arm pointing performance in a 3D real-world (3D-RWPT) paradigm using a recently established pointing device. A heterogeneous group of 121 participants (mean age 56.5 ± 17.7 years, 52 females), including 16 healthy volunteers and 105 patients with different vestibular, ocular motor and degenerative brain disorders, was included in this study. A high correlation was found between 2D perspective task and 3D pointing along the horizontal (azimuth) but not along the vertical (polar) plane. Self-estimated navigation ability (SBSODS) could not reliably predict actual performance in either 2D- or 3D-tests. Clinical assessment of spatial orientation and memory should therefore include measurements of actual performance, based on a 2D pen-and-paper test or a 3D pointing task, rather than memory-based questionnaires, since solely relying on the patient's history of self-estimated navigation ability results in misjudgments. The 3D finger-arm pointing test (3D-RWPT) reveals additional information on vertical (polar) spatial performance which goes undetected in conventional 2D pen-and-paper tests. Diseases or age-specific changes of spatial orientation in the vertical plane should not be clinically neglected. The major aim of this pilot study was to compare the practicability and capability of the three tests but not yet to prove their use for differential diagnosis. The next step will be to establish a suitable clinical bedside test for spatial memory and orientation.

The CCAS-scale in hereditary ataxias: helpful on the group level, particularly in SCA3, but limited in individual patients.

BACKGROUND: A brief bedside test has recently been introduced by Hoche et al. (Brain, 2018) to screen for the Cerebellar Cognitive Affective Syndrome (CCAS) in patients with cerebellar disease. OBJECTIVE: This multicenter study tested the ability of the CCAS-Scale to diagnose CCAS in individual patients with common forms of hereditary ataxia. METHODS: A German version of the CCAS-Scale was applied in 30 SCA3, 14 SCA6 and 20 FRDA patients, and 64 healthy participants matched for age, sex, and level of education. Based on original cut-off values, the number of failed test items was assessed, and CCAS was considered possible (one failed item), probable (two failed items) or definite (three failed items). In addition a total sum raw score was calculated. RESULTS: On a group level, failed items were significantly higher and total sum scores were significantly lower in SCA3 patients compared to matched controls. SCA6 and FRDA patients performed numerically below controls, but respective group differences failed to reach significance. The ability of the CCAS-Scale to diagnose CCAS in individual patients was limited to severe cases failing three or more items. Milder cases failing one or two items showed a great overlap with the performance of controls exhibiting a substantial number of false-positive test results. The word fluency test items differentiated best between patients and controls. CONCLUSIONS: As a group, SCA3 patients performed below the level of SCA6 and FRDA patients, possibly reflecting additional cerebral involvement. Moreover, the application of the CCAS-Scale in its present form results in a high number of false-positive test results, that is identifying controls as patients, reducing its usefulness as a screening tool for CCAS in individual patients.

Different strategies in pointing tasks and their impact on clinical bedside tests of spatial orientation.

Deficits in spatial memory, orientation, and navigation are often early or neglected signs of degenerative and vestibular neurological disorders. A simple and reliable bedside test of these functions would be extremely relevant for diagnostic routine. Pointing at targets in the 3D environment is a basic well-trained common sensorimotor ability that provides a suitable measure. We here describe a smartphone-based pointing device using the built-in inertial sensors for analysis of pointing performance in azimuth and polar spatial coordinates. Interpretation of the vectors measured in this way is not trivial, since the individuals tested may use at least two different strategies: first, they may perform the task in an egocentric eye-based reference system by aligning the fingertip with the target retinotopically or second, by aligning the stretched arm and the index finger with the visual line of sight in allocentric world-based coordinates similar to using a rifle. The two strategies result in considerable differences of target coordinates. A pilot test with a further developed design of the device and an app for a standardized bedside utilization in five healthy volunteers revealed an overall mean deviation of less than 5° between the measured and the true coordinates. Future investigations of neurological patients comparing their performance before and after changes in body position (chair rotation) may allow differentiation of distinct orientational deficits in peripheral (vestibulopathy) or central (hippocampal or cortical) disorders.

Interleukin-6 bedside test in detecting chorioamnionitis in women with preterm premature rupture of fetal membranes.

OBJECTIVES: About 30-80% of preterm deliveries following preterm premature rupture of fetal membranes (PPROM) are complicated by histological chorioamnionitis. To evaluate the accuracy of Interleukin-6 (IL-6) bedside test in detecting chorioamnionitis in women with PPROM. MATERIAL AND METHODS: One hundred and ten (110) pregnant women with PPROM > 24 and < 34 weeks' gestation, admitted for conservative management were included in this study. Participants were examined on admission using sterile speculum examination for assessment of IL-6 in the cervico-vaginal secretions using the IL-6 bedside test. The IL-6 bedside test was repeated for all participants once termination of pregnancy (TOP) decided. After TOP, placenta, umbilical cord, and fetal membranes samples were examined for histologic detection of chorioamnionitis (gold standard). The histological results were compared with IL-6 bedside test results to evaluate the accuracy of IL-6 bedside test in detecting chorioamnionitis in women with PPROM. RESULTS: The IL-6 bedside test had 98.6% sensitivity, 94.7% specificity, 97.3% positive predictive value (PPV), 97.3% negative predictive value (NPV) and 97.3% overall accuracy in detecting chorioamnionitis. The sensitivity, specificity, NPV and overall accuracy of IL-6 bedside test (98.6%, 94.7%, 97.3%, and 97.3%; respectively) were significantly higher than the clinical and laboratory parameters of chorioamnionitis (65.3%, 57.9%, 46.8%, and 62.7%; respectively) (p = 0.04, 0.02, 0.001 and 0.03; respectively). CONCLUSIONS: The IL-6 bedside test is an accurate, non-invasive bedside test with 98.6% sensitivity, 94.7% specificity, 97.3% PPV, 97.3% NPV, and 97.3% overall accuracy in detecting chorioamnionitis. The IL-6 bedside test had significantly higher sensitivity, specificity, NPV, and overall accuracy than the clinical and laboratory parameters of chorioamnionitis.

Validation of a German version of the Cerebellar Cognitive Affective/ Schmahmann Syndrome Scale: preliminary version and study protocol.

BACKGROUND: Traditionally, cerebellar disorders including ataxias have been associated with deficits in motor control and motor learning. Since the 1980's growing evidence has emerged that cerebellar diseases also impede cognitive and affective processes such as executive and linguistic functions, visuospatial abilities and regulation of emotion and affect. This combination of non-motor symptoms has been named Cerebellar Cognitive Affective/ Schmahmann Syndrome (CCAS). To date, diagnosis relies on non-standardized bedside cognitive examination and, if available, detailed neuropsychological test batteries. Recently, a short and easy applicable bedside test (CCAS Scale) has been developed to screen for CCAS. It has been validated in an US-American cohort of adults with cerebellar disorders and healthy controls. As yet, the CCAS Scale has only been available in American English. We present a German version of the scale and the study protocol of its ongoing validation in a German-speaking patient cohort. METHODS: A preliminary German version has been created from the original CCAS Scale using a standardized translation procedure. This version has been pre-tested in cerebellar patients and healthy controls including medical experts and laypersons to ensure that instructions are well understandable, and that no information has been lost or added during translation. This preliminary German version will be validated in a minimum of 65 patients with cerebellar disease and 65 matched healthy controls. We test whether selectivity and sensitivity of the German CCAS Scale is comparable to the original CCAS Scale using the same cut-off values for each of the test items, and the same pass/ fail criteria to determine the presence of CCAS. Furthermore, internal consistency, test-retest and interrater reliability will be evaluated. In addition, construct validity will be tested in a subset of patients and controls in whom detailed neuropsychological testing will be available. Secondary aims will be examination of possible correlations between clinical features (e.g. disease duration, clinical ataxia scores) and CCAS scores. PERSPECTIVE: The overall aim is to deliver a validated bedside test to screen for CCAS in German-speaking patients which can also be used in future natural history and therapeutic trials. STUDY REGISTRATION: The study is registered at the German Clinical Study Register (DRKS-ID: DRKS00016854).

Diagnostic accuracy of a smartphone bedside test to assess the fixation suppression of the vestibulo-ocular reflex: when nothing else matters.

OBJECTIVE: Validation of a bedside test to objectify the fixation suppression of the vestibulo-ocular reflex (FS-VOR) in patients with a cerebellar syndrome and healthy controls. METHODS: The vestibulo-ocular reflex and its fixation suppression were assessed by video-nystagmography (VNG) in 20 healthy subjects (mean age 56 ± 15) and 19 patients with a cerebellar syndrome (mean age 70 ± 11). The statistical cutoff delineating normal from pathological FS-VOR was determined at the 2.5th percentile of the normal distribution of the healthy cohort. VNG was then compared to a bedside test, where eye movements were recorded with a smartphone while patients were rotated on a swivel chair at a defined speed and amplitude. These videos were rated as normal or pathological FS-VOR by six blinded raters, and results compared to VNG. RESULTS: VNG in healthy controls showed FS-VOR with a reduction of nystagmus beats by 95.0% ± 7.2 (mean ± SD). The statistical cutoff was set at 80.6%. Cerebellar patients reduced nystagmus beats by only 26.3% ± 25.1. Inter-rater agreement of the smartphone video ratings was 85%. The sensitivity of the video ratings to detect an impaired FS-VOR was 99%, its specificity 92%. Inter-test agreement was 91%. CONCLUSION: The smartphone bedside test is an easily performed, reliable, sensitive, specific, and inexpensive alternative for assessing FS-VOR.

[Premature rupture of the membranes: analytical evaluation of diagnostic tests]. / Rupture prématurée des membranes : étude comparative des performances analytiques des tests de diagnostic biologique.

Premature rupture of the membranes (PROM) is a frequent event affecting 3% of pregnancies. PROM causes 30% of premature deliveries and 20% of perinatal mortality. The diagnosis relies mainly on the clinical visualization of the amniotic fluid flow in the vagina. If not, clinicians can use bedside tests detecting either the change of the vaginal pH or the presence of amniotic components mainly IGFBP-1 or AFP in the vaginal fluid. We aimed to study the technical and analytical characteristics of 5 immunochromatographic tests (easyProm®, ActimProm®, Toda Amniodiag 5 strip®, Amnioquick® Duo, Amnisure®) that mainly detect IGFBP-1 in order to compare our results with the data from the manufacturer. We evaluated the pre-analytical phase (sampling, sample stability and elution) and the analytical phase (limit of detection, reading time and interferences related to a physiological contamination). Compliance with the pre-analytical step is crucial because the absorption and the elution of the samples in the buffer vary with the swab. Once eluted, the sample is stable. The recommended reading times are adequate but must not be exceeded, otherwise the result can be falsely positive. The detection limits announced appear to be to optimistic. The presence of maternal blood but not maternal urine can perturb the results.

Distinguishing Motor Weakness From Impaired Spatial Awareness: A Helping Hand!

Our patient, aged 73 years, had background peripheral neuropathy of unknown cause, stable for several years, which caused some difficulty in walking on uneven ground. He attended for a teaching session but now staggered in, a new development. He had apparent weakness of his right arm, but there was difficulty in distinguishing motor weakness from impaired spatial awareness suggestive of parietal lobe dysfunction. With the patient seated, eyes closed, and left arm outstretched, S.A.R. lifted the patient's right arm and asked him to indicate when both were level. This confirmed motor weakness. Urgent computed tomographic scan confirmed left subdural haematoma and its urgent evacuation rapidly resolved the patient's symptoms. Intrigued by our patient's case, we explored further and learnt that in rehabilitation medicine, the awareness of limb position is commonly viewed in terms of joint position sense. We present recent literature evidence indicating that the underlying mechanisms are more subtle.

Comparison of rapid bedside tests for phosphorylated insulin-like growth factor-binding protein 1 and fetal fibronectin to predict preterm birth.

OBJECTIVE: To compare the accuracy of rapid bedside tests for phosphorylated insulin-like growth factor-binding protein 1 (phIGFBP-1) and fetal fibronectin (fFN) to predict preterm delivery among women with threatened preterm labor. METHODS: A prospective observational study was conducted among women with a singleton pregnancy of 28-36 weeks, intact membranes, and symptoms suggestive of preterm labor who attended a center in New Delhi, India, between April 1, 2011, and March 31, 2014. Rapid bedside tests were performed at presentation to measure the levels of phIGFBP-1 and fFN in cervicovaginal secretions. All patients were managed as per the standard hospital protocol and followed up until delivery. RESULTS: Data were available for 468 participants. For delivery before 37 weeks, the phIGFBP-1 test exhibited a sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 81.1%, 97.1%, 95.2% and 87.7%, respectively. The sensitivity, specificity, PPV, and NPV for the fFN test were 19.4%, 99.4%, 97.4%, and 63.2%, respectively. The phIGFBP-1 test displayed higher sensitivity and NPV than did the fFN test for delivery before 34 weeks and within 7 days of testing (P<0.05 for all). CONCLUSION: The rapid bedside test for phIGFBP-1 was more reliable in the prediction of preterm delivery than was the equivalent test for fFN.