Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “diagnostic algorithm”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 613 records · Page 34Linked to original sources

23. Clinical laboratory assessment of IgE-dependent hypersensitivity.

This chapter reviews clinical and laboratory analyses that aid in the diagnosis and management of human allergic (IgE-dependent) diseases. The diagnostic algorithm for immediate-type hypersensitivity begins with a thorough clinical history and physical examination. Once signs and symptoms compatible with an allergic disorder have been identified, a skin test and/or blood test for allergen-specific IgE antibodies may serve as primary confirmation to strengthen the diagnosis. Puncture and intradermal skin testing provide a biologically relevant immediate-type hypersensitivity response in the skin, with resultant wheal and flare reactions within 15 minutes of allergen application. Bleeding, dermatographism, and antihistamines may confound the quality of the skin test. Allergen-specific IgE antibody may also be detected in the blood using a radioallergosorbent test (RAST). Nonisotopic "second-generation" RAST-type assays have evolved to provide more quantitative, sensitive, precise IgE antibody results. In vivo provocation tests may serve as secondary confirmatory tests when the clinical history is discordant with a primary IgE antibody test result. The multiallergen screen is a qualitative RAST-type assay that detects specific IgE antibody to approximately 15 allergens that evoke a large majority of aeroallergen or food-related allergic disorders. Other useful serological assays performed in the diagnostic allergy laboratory include total serum IgE, Hymenoptera venom-specific IgG antibody, IgG precipitins for organic dusts, mast cell tryptases, and the venom RAST inhibition test. Above all, in vivo or laboratory confirmatory test results that are inconsistent with the clinical history should be repeated as for any laboratory assessment.

Algorithms↗

The diagnostic evaluation of pulmonary embolism.

Due to the morbidity and mortality associated with either untreated disease or inappropriate anticoagulant therapy, accurate diagnosis of pulmonary embolism is essential. Pulmonary angiography, the current gold standard test for diagnosing pulmonary embolus, is both invasive and costly; therefore, noninvasive diagnostic strategies have been developed. Noninvasive tests often have to be combined to either raise the posttest probability of disease to a level justifying treatment or lower it to a level at which withholding treatment is warranted. Diagnostic algorithms involving clinical assessment; venous ultrasonography; D-dimer testing; ventilation-perfusion lung scanning; and, more recently, computed tomography have been validated in management trials of patients with a suspected pulmonary embolism. The optimal strategy at individual institutions is dependent on local availability, expertise, and cost. Magnetic resonance imaging and combined computed tomographic pulmonary angiography and venography possess the potential to be used as stand-alone tests for pulmonary embolism but require further evaluation.

Diagnostic Techniques, Cardiovascular↗

Chronic epididymitis (epididymal nodule) mimicking an adenomatoid tumor--case report with review of literature.

AIM: To describe and review the differential diagnosis of epididymal nodules and chronic epididymitis so as to have a broad view of this pathology. We have suggested a possible diagnostic algorithm for the workup of an epididymal nodule. METHODS/RESULTS: We have reported a case of a 35-year-old patient with a symptomatic palpable nodular mass in the tail of the left epididymis. Fine needle aspiration suggested an adenomatoid tumor while the surgical excision histology was reported as chronic epididymitis. CONCLUSIONS: Epididymal nodules are frequently encountered in the epididymis. Their differential diagnosis includes chronic granulomatous epididymitis, adenomatoid tumor and benign paratesticular neoplasms. We consider that it is important to distinguish epididymal nodules from benign inflammatory lesions and the threshold for a surgical excision should be low as it is therapeutic and provides a definite diagnosis. Whilst the FNAC alone may not be always adequate to confirm diagnosis, an epididymectomy may be curative as well as diagnostic in selected cases.

Adenomatoid Tumor↗

Does this patient have deep vein thrombosis?

CONTEXT: Outpatients with suspected deep vein thrombosis (DVT) have nonspecific signs and symptoms. Missed DVT diagnosis may result in fatal pulmonary embolism. Since many patients may have DVT, a selective and efficient diagnostic process is needed. OBJECTIVE: To systematically review trials that determined the prevalence of DVT using clinical prediction rules either with or without D-dimer, for the diagnosis of DVT. DATA SOURCES: English- and French-language studies were identified from MEDLINE from 1990 to July 2004 and supplemented by a review of all relevant bibliographies. STUDY SELECTION: We included studies that prospectively enrolled consecutive, unselected outpatients with suspected DVT and applied clinical prediction rules before D-dimer testing or diagnostic imaging. All studies included sufficient information to allow the calculation of the prevalence of DVT for at least 1 of the 3 clinical probability estimates (low, moderate, or high). We required that patients be followed up for a minimum 3-month period. Unless the clinical model incorporated prior DVT, studies were excluded if patients with a history of prior DVT were enrolled. DATA EXTRACTION: Two reviewers independently reviewed and abstracted data for estimating the prevalence of DVT, sensitivity, specificity, and likelihood ratios (LRs) of D-dimer in each of the 3 clinical probability estimates. Data for the D-dimer in all studies were pooled and analyzed as high-sensitivity/low-specificity test or a moderate-sensitivity/moderate-specificity test. DATA SYNTHESIS: Fourteen studies involving more than 8000 patients used 1 clinical prediction rule for diagnosing DVT, of which 11 incorporated D-dimer testing in the diagnostic algorithm. The prevalence of DVT in the low, moderate, and high clinical probability groups was 5.0% (95% CI, 4.0%-8.0%), 17% (95% CI, 13%-23%), and 53% (95% CI, 44%-61%), respectively. The overall prevalence of DVT was 19% (95% CI, 16%-23%). Pooling all studies, the sensitivity, specificity, and negative LRs of D-dimer testing in the low probability group were 88% (95% CI, 81%-92%), 72% (95% CI, 65%-78%), and 0.18% (95% CI, 0.12-0.18); in the moderate probability group: 90% (95% CI, 80%-95%), 58% (95% CI, 49%-67%), and 0.19% (95% CI, 0.11-0.32); and in the high probability group: 92% (95% CI, 85%-96%), 45% (95% CI, 37%-52%), and 0.16% (95% CI, 0.09-0.30). The LRs for a normal result on a high or moderately sensitive D-dimer assay among patients with: (1) low clinical suspicion were 0.10 (95% CI, 0.03-0.37) and 0.20 (95% CI, 0.12-0.31); (2) moderate clinical suspicion were 0.05 (95% CI, 0.01-0.21) and 0.23 (95% CI, 0.13-0.39); and (3) high clinical suspicion were 0.07 (95% CI, 0.03-0.18) and 0.15 (95% CI, 0.10-0.38). CONCLUSIONS: Diagnostic accuracy for DVT improves when clinical probability is estimated before diagnostic tests. Patients with low clinical probability on the predictive rule have prevalence of DVT of less than 5%. In low-probability patients with negative D-dimer results, diagnosis of DVT can be excluded without ultrasound; in patients with high clinical suspicion for DVT, results should not affect clinical decisions.

Algorithms↗

Abnormalities of dystrophin, the sarcoglycans, and laminin alpha2 in the muscular dystrophies.

Abnormalities of dystrophin, the sarcoglycans, and laminin alpha2 are responsible for a subset of the muscular dystrophies. In this study we aim to characterise the nature and frequency of abnormalities of these proteins in an Australian population and to formulate an investigative algorithm to aid in approaching the diagnosis of the muscular dystrophies. To reduce ascertainment bias, biopsies with dystrophic (n=131) and non-dystrophic myopathic (n=71) changes were studied with antibodies to dystrophin, alpha, beta, and gamma sarcoglycan, beta dystroglycan, and laminin alpha2, and results were correlated with clinical phenotype. Abnormalities of dystrophin, the sarcoglycans, or laminin alpha2 were present in 61/131 (47%) dystrophic biopsies and in 0/71 myopathic biopsies, suggesting that immunocytochemical study of dystrophin, the sarcoglycans, and laminin alpha2 may, in general, be restricted to patients with dystrophic biopsies. Two patients with mutations identified in gamma sarcoglycan had abnormal dystrophin (by immunocytochemistry and immunoblot), showing that abnormalities of dystrophin may be a secondary phenomenon. Therefore, biopsies should not be excluded from sarcoglycan analysis on the basis of abnormal dystrophin alone. The diagnostic yield was highest in those with severe, rapidly progressive limb-girdle weakness (92%). Laminin alpha2 deficiency was identified in 5/131 (4%) patients; 215 patients presented after infancy, indicating that abnormalities of laminin alpha2 are not limited to the congenital muscular dystrophy phenotype. Overall patterns of immunocytochemistry and immunoblotting provided a guide to mutation analysis and, on the basis of this study, we have formulated a diagnostic algorithm to guide the investigation of patients with muscular dystrophy.

Adolescent↗

Type 1 laryngeal cleft: establishing a functional diagnostic and management algorithm.

OBJECTIVES: To report our experience with all patients diagnosed with type 1 laryngeal cleft over a period of 3 years in our referral practice and to describe a functional diagnostic and management algorithm for children with this disorder. METHODS: A prospective longitudinal study in a tertiary care referral center. Twenty pediatric patients diagnosed with type 1 laryngeal cleft in a 3-year period (5/1/2002-5/1/2005) were included in this study. The incidence, presenting symptoms, diagnostic procedures, medical and surgical interventions performed, and clinical outcomes were evaluated. RESULTS: The incidence of type 1 laryngeal cleft was 7.6%. Among the 20 patients in this study, aspiration with thin liquids was the most common presenting symptom (18 patients, 90%). Three patients underwent modified barium swallow (MBS) alone, 3 patients underwent functional endoscopic evaluation of swallow (FEES) alone, and 11 patients underwent both MBS and FEES prior to intraoperative endoscopic evaluation. Four patients (20%) were successfully treated with conservative therapy. Sixteen patients (80%) required endoscopic surgical repair after failing a course of conservative measures. The success rate of surgical repair was 94% (15 out of 16 patients). CONCLUSIONS: Type 1 laryngeal cleft can be challenging diagnostically. We propose a functional diagnostic and management algorithm that includes MBS, FEES, suspension laryngoscopy with bimanual interarytenoid palpation, and a trial of conservative therapy, as a way to diagnose and manage type 1 laryngeal cleft prior to consideration of surgical repair. If conservative therapy fails, then surgical intervention is indicated.

Algorithms↗

Do older Australians truly have low rates of anxiety and depression? A critique of the 1997 National Survey of Mental Health and Wellbeing.

This paper sets out to critically evaluate reports from the Australian-wide National Survey of Mental Health and Wellbeing of very low rates of ICD-10 anxiety and depressive disorders in community resident older Australians. Data from the National Survey, which relied on the Composite International Diagnostic Interview (CIDI) were re-computed and re-analysed to address concerns about population sampling, interview response patterns and alternate measures of mental health. Rates of anxiety and depressive disorders fell to low levels after 65 years and continued to fall thereafter. This is at odds with findings from gerontological surveys that used assessment tools better suited to frail older people. Scores on mental health scales, together with diagnostic algorithms that obviated CIDI skip patterns, showed much less change in mental wellbeing across generations. It is argued that sampling and case ascertainment bias combined to reduce rates of anxiety and depression in very old people, especially when adjustments are made for the high morbidity levels encountered in aged residential facilities. Functional mental disorders almost certainly rise in frequency in advanced old age, often in conjunction with dementia.

Adult↗

Anterior hip pain in the adult: an algorithmic approach to diagnosis.

The adult patient who complains of anterior hip pain is a dilemma frequently encountered by the primary care physician. Detailed history taking, physical examination, and plain x-ray films are indicated for the initial evaluation. Anterior hip pain is often diagnosed as musculoskeletal strain/sprain and treated with a conservative regimen represented by the acronym NICER (nonsteroidal anti-inflammatory drugs, ice, compression, elevation, and rest) with or without physical therapy. On occasion, this therapy fails to eradicate the symptoms. When these symptoms are refractory to diagnosis by conventional means, a more comprehensive evaluation of the etiology is warranted. Refractory pain is defined in the authors' practice as pain that persists after 4 weeks of initial conservative management. This subsequent evaluation includes the use of such laboratory tests as complete blood cell count with differential count, Chem 20 health profile, erythrocyte sedimentation rate, and an arthritic panel (assessment of rheumatoid factor, antinuclear antibody, C-reactive protein). Ancillary radiologic tests warranted include a nuclear bone scan, a magnetic resonance imaging scan, a computed tomography arthrogram with hip aspiration, and/or a scan of white blood cells labeled with indium 111. The test chosen depends on the etiology most suspected. A useful diagnostic algorithm for the investigation of anterior hip pain in the adult is provided. An illustrative case presentation of carcinoma of an unknown primary site presenting as anterior hip pain demonstrates the algorithm as it applies in the authors' practice.

Adenocarcinoma↗

Clinical pulmonary infection score for ventilator-associated pneumonia: accuracy and inter-observer variability.

OBJECTIVE: Although quantitative microbiological cultures of samples obtained by bronchoscopy are considered the most specific tool for diagnosing ventilator-associated pneumonia, this labor-intensive invasive technique is not widely used. The Clinical Pulmonary Infection Score (CPIS), a diagnostic algorithm that relies on easily available clinical, radiographic, and microbiological criteria, could be an attractive alternative for diagnosing ventilator-associated pneumonia. Initially, the CPIS scoring system was validated upon 40 quantitative cultures of bronchoalveolar lavage fluid from 28 patients, and only few other studies have evaluated this scoring system since then. Therefore, little is known about the accuracy of this score. DESIGN: We compared the scores of a slightly adjusted CPIS with results from quantitative cultures of bronchoalveolar lavage fluid in 99 consecutive patients with suspicion of ventilator-associated pneumonia, using growth of > or =10(4) cfu/ml in bronchoalveolar lavage fluid as a cut-off for diagnosing ventilator-associated pneumonia. In addition, the CPIS were calculated for 52 patients by two different intensivists to determine the inter-observer variability. RESULTS: Ventilator-associated pneumonia was diagnosed in 69 (69.6%) patients. When using a CPIS >5 as diagnostic cutoff, the sensitivity of the score was 83% and its specificity was 17%. The area under the Receiver Operating Characteristic curve was 0.55. The level of agreement for prospectively measured Clinical Pulmonary Infection Score (< or =6 and >6) was poor (kappa =0.16). CONCLUSIONS: When compared to quantitative cultures of bronchoalveolar lavage fluid, the CPIS has a low sensitivity and specificity for diagnosing ventilator-associated pneumonia with considerable inter-observer variability.

Adult↗

Reduction in voiding cystourethrographies after the introduction of contrast enhanced sonographic reflux diagnosis.

BACKGROUND: Voiding urosonography (VUS) using the intravesical application of an US contrast medium (Levovist) has been shown to have very high sensitivity and specificity in the diagnosis of vesicoureteric reflux (VUR) compared to voiding cystourethrography (VCUG). OBJECTIVE: To determine the extent of reduction of VCUGs after adding VUS to the diagnostic algorithm of VUR. MATERIALS AND METHODS: Over 2 years, 449 children (162 boys, 287 girls) were referred for diagnosis of possible VUR. The selection of a particular reflux examination was based on pre-defined criteria. VUS was performed primarily in girls and follow-up cases. The indications for VCUG were as follows: (a) boys - first examination for VUR, (b) specific request for urethra or bladder imaging, (c) girls - when VUR was diagnosed in the VUS and no VCUG had been done previously, and (d) inadequate VUS. RESULTS: VCUGs were primarily carried out in 141 cases. VUSs were performed in 308 patients. In 69 of these patients a VCUG followed during the same examination session. Thus 239 of 449 patients underwent only VUS, resulting in reduction of the VCUGs by 53 %. CONCLUSIONS: The number of VCUGs was significantly reduced as a result of the implementation of VUS as part of the routine diagnostic imaging modality for VUR. Consequently, the number of children that would have been exposed to ionising radiation was reduced by over half.

Adolescent↗

DSM criteria for major depression: evaluating symptom patterns using latent-trait item response models.

BACKGROUND: Expert committees of clinicians have chosen diagnostic criteria for psychiatric disorders with little guidance from measurement theory or modern psychometric methods. The DSM-III-R criteria for major depression (MD) are examined to determine the degree to which latent trait item response models can extract additional useful information. METHOD: The dimensionality and measurement properties of the 9 DSM-III-R criteria plus duration are evaluated using dichotomous factor analysis and the Rasch and 2 parameter logistic item response models. Quantitative liability scales are compared with a binary DSM-III-R diagnostic algorithm variable to determine the ramifications of using each approach. RESULTS: Factor and item response model results indicated the 10 MD criteria defined a reasonably coherent unidimensional scale of liability. However, person risk measurement was not optimal. Criteria thresholds were unevenly spaced leaving scale regions poorly measured. Criteria varied in discriminating levels of risk. Compared to a binary MD diagnosis, item response model (IRM) liability scales performed far better in (i) elucidating the relationship between MD symptoms and liability, (ii) predicting the personality trait of neuroticism and future depressive episodes and (iii) more precisely estimating heritability parameters. CONCLUSIONS: Criteria for MD largely defined a single dimension of disease liability although the quality of person risk measurement was less clear. The quantitative item response scales were statistically superior in predicting relevant outcomes and estimating twin model parameters. Item response models that treat symptoms as ordered indicators of risk rather than as counts towards a diagnostic threshold more fully exploit the information available in symptom endorsement data patterns.

Adolescent↗

Coronary heart disease surveillance: field application of an epidemiologic algorithm.

This report describes the performance of a surveillance system and computerized algorithm for the assignment of definite or probable hospitalized cardiac events for large epidemiologic studies. The algorithm, developed by the Coordinating Committee for Community Demonstration Studies (CCCDS), evolved from the Gillum criteria, and included selected ICD-9-CM codes including codes 410 through 414 for discharge record screening, plus creatine kinase. For the small percentage of cases in which enzyme analysis was inconclusive (8%), presence of pain and/or Minnesota-coded electrocardiograms were included to define the outcome. All data items were easily obtained from medical records by trained lay record abstractors and required no interpretation. From January 1980 through December 1991, 21,183 medical records were screened for ICD-9-CM codes 410 through 414. Of all 410 to 411 ICD-9-CM codes (n = 9026), 36.9% (n = 3220) were classified as definite cardiac events and 10.6% (n = 1057) as probable events. Of all 412 through 414 codes (n = 9070), only 1.8% (n = 227) were classified as definite cardiac events and 5.4% (n = 716) as probable events. The epidemiologic diagnostic algorithm presented in this article used computerized data to assign diagnoses in a standard, objective manner, and was a lower cost alternative to classification of cardiac events on the basis of clinical review and/or more complex record abstraction approaches.

Abstracting and Indexing↗

Diagnosing delirium by telephone.

To determine whether delirium can be diagnosed by telephone, we interviewed 41 subjects aged 65 years or older 1 month after repair of hip fracture, first by telephone and then face-to-face. Interviews included the modified telephone Mini-Mental State Examination and the Delirium Symptom Interview. Delirium was diagnosed using the Confusion Assessment Method diagnostic algorithm, and the telephone results were compared with the face-to-face results (the "gold standard"). Of 41 subjects, 6 were delirious by face-to-face assessment; all 6 were delirious by telephone (sensitivity 1.00). Of 35 patients not delirious by face-to-face assessment, 33 patients were not delirious by telephone (specificity = 0.94). We conclude that telephone interviews can effectively rule out delirium, but the positive diagnosis should be confirmed by a face-to-face assessment, especially in populations with a low prevalence of delirium.

Aged↗

Inherited thrombocytopenias: from genes to therapy.

BACKGROUND AND OBJECTIVES: Inherited thrombocytopenias are a heterogeneous group of rare diseases characterized by a reduced number of blood platelets. Some of these diseases are exclusive to megakaryocytes and platelets, while in others the pathology extends to other cell types. Although the defective genes, coding for membrane glyoproteins, cytoskeleton components and intracellular signaling pathways, as well as transcription factors, have been identified in most cases, the pathophysiology of these disorders is often unknown. This review describes recent contributions to clinical and diagnostic aspects, biology and treatments of familial thrombocytopenias. EVIDENCE AND INFORMATION SOURCES: The information presented here derives from literature and the experience of the authors. The most relevant studies are critically analyzed and discussed. STATE OF ART: The clinical and laboratory features of most of the inherited thrombocytopenias have been reviewed. The different forms have been classified into 3 groups depending on platelet volume. Although this criterion is not completely satisfactory, it is one of the most useful in diagnostic algorithms. We report on recent advances in Wiskott-Aldrich and Bernard-Soulier syndromes, as well as in MYH9-related diseases, a new nosological entity that groups old distinct forms known as May-Hegglin anomaly, Sebastian, Fetchner, and Epstein syndromes. Other, less frequent forms are also discussed, including non-syndromic forms of mild thrombocytopenia that are genetically heterogeneous. PERSPECTIVES: In the past, inherited thrombocytopenias were considered exceedingly rare and the number of well-defined forms was very small. In the last few years, the widespread diffusion of electronic cell counters has allowed these conditions to be detected more frequently and several new entities have been identified through the co-ordinated efforts of physicians, biologists and geneticists. The pathogenesis of many new and old forms is being unraveled, thus providing insights on the molecular basis of platelet production and function. This knowledge will be a valuable resource for clinicians in the diagnostic approaches to such disorders.

Abnormalities, Multiple↗

Immunohistochemical analysis of the biological potential of odontogenic keratocysts.

BACKGROUND: The aim of this study was to analyse the usefulness of detecting important apoptosis and proliferation markers in assessing the biological potential of odontogenic keratocysts (OKC) and thus selecting the optimal diagnostic algorithm for these lesions. METHODS: Indirect immunohistochemistry and relevant statistical methods were used for analysis of formalin-fixed and paraffin-embedded samples from 98 patients. RESULTS: Nevoid basal cell carcinoma syndrome (NBCCS) keratocysts were characterized by higher expression of Bcl-2, p27Kip1 and c-erbB-2 as well as by lower proliferative activity measured by Ki-67 in basal cell epithelium and by a lower inflammatory response in comparison with sporadic keratocysts. Dentigerous, radicular and non-specified odontogenic cysts differed from both NBCCS and sporadic keratocysts in a wide spectrum of apoptosis and/or cell cycle-related protein expressions, higher proliferation in the basal cell layer, and vice versa, lower proliferation in the suprabasal cell layer. CONCLUSIONS: The NBCCS keratocysts have a different immunophenotype from sporadic keratocysts and both types are distinguishable from dentigerous, radicular and non-specified odontogenic cysts. These findings confirm the separate biological potential of these lesions and the results of the immunohistochemical analysis have diagnostic and prognostic implications.

Apoptosis↗

Respiratory-onset peripartum cardiomyopathy: a systematic review of diagnostic pitfalls and clinical outcomes.

INTRODUCTION: Peripartum cardiomyopathy (PPCM) may initially present with prominent respiratory symptoms that resemble primary pulmonary disease, particularly in late pregnancy and the early postpartum period. In clinical practice, this presentation often triggers alternative diagnostic pathways, introducing delay at a time when rapid cardiac assessment is critical. Although respiratory-dominant presentations are repeatedly described across case-based and observational reports, they have not been systematically examined as a distinct diagnostic pathway within the PPCM literature. CONTENT: This PRISMA-guided systematic review synthesized evidence relating to respiratory-onset presentations of PPCM. Major databases and registers were searched comprehensively. Following screening of 589 records and full-text assessment of 145 reports, 49 studies met inclusion criteria. Twenty studies were qualitatively prioritized for narrative synthesis using ROBIS-informed methodological appraisal. Evidence was examined across diagnostic misclassification patterns, cardiopulmonary mechanisms, differential diagnoses, investigative strategies, and acute and longitudinal management considerations. SUMMARY: Respiratory-led presentations were commonly misattributed to asthma, pneumonia, pulmonary embolism, or perioperative causes, with diagnostic delay frequently reported. Across heterogeneous study designs, cardiogenic pulmonary edema with left-ventricular systolic dysfunction emerged as a recurring unifying mechanism. Early use of echocardiography, natriuretic peptides, and targeted imaging consistently aided differentiation from primary respiratory pathology. Severe clinical deterioration was often described in the context of delayed recognition. OUTLOOK: Respiratory-onset PPCM represents a high-risk diagnostic pathway rather than a discrete disease entity. Prospective registries, standardized diagnostic algorithms, and closer integration of obstetric and cardiopulmonary care are needed to refine early recognition and improve maternal outcomes.

Humans↗

Diagnosis and treatment of venous thromboembolism.

The diagnosis of deep vein thrombosis (DVT) and pulmonary embolism (PE) has been improved and simplified over the past decade thanks to advances in noninvasive and readily accessible technology. With high degrees of sensitivity and specificity, venous ultrasonography is favored as the initial investigation for DVT. To diagnose PE, most clinicians rely on diagnostic algorithms that combine clinical assessment, noninvasive lung studies, and, if necessary, venous ultrasonography of the legs and D-dimer testing. Substantial progress has also occurred in the treatment of acute venous thromboembolism with the introduction of low-molecular-weight heparins. This class of antithrombotic agents has changed initial therapy from an inpatient, intravenous regimen that required laborious monitoring to an outpatient practice using weight-adjusted doses of once-daily subcutaneous injections. In addition, several new anticoagulants with theoretical advantages over existing agents have entered phase III studies. Aspects of thrombosis treatment that remain controversial include vena caval interruption and the indications for thrombolysis and surgical thromboembolectomy.

Diagnostic Imaging↗

Respiratory dead space measurement in the investigation of pulmonary embolism in outpatients with pleuritic chest pain.

STUDY OBJECTIVES: Pleuritic chest pain is a common presenting condition in the emergency department. A noninvasive bedside rule out test for pulmonary embolism would aid investigating this patient group. Our study aimed to compare the clinical utility of three methods for calculating respiratory dead space in the diagnosis of pulmonary embolism in outpatients with pleuritic chest pain. DESIGN: Prospective diagnostic study. SETTING: Large city-center emergency department. PATIENTS: Between February 2002 and June 2003, 425 patients presenting to the emergency department with pleuritic chest pain were prospectively recruited. INTERVENTION: Data collection for respiratory dead space was performed in the emergency department by two researchers. The respiratory dead space fraction was calculated independently using three different methods. All patients underwent an independent reference standard diagnostic algorithm to establish the presence or absence of pulmonary embolism. Those with a low modified Wells clinical probability and a normal quantitative d-dimer finding were discharged home. All others followed a reference standard protocol using Prospective Investigation of Pulmonary Embolism Diagnosis-interpreted ventilation/perfusion scanning, CT pulmonary angiography, and digital subtraction pulmonary angiography. All patients were followed up clinically for 3 months. MEASUREMENTS AND RESULTS: For the Bohr calculation, the area under the receiver operating characteristic curve was 0.62 (95% confidence interval [CI], 0.51 to 0.73), the Enghoff calculation was 0.66 (95% CI, 0.55 to 0.77), and the capillary sample Enghoff was 0.62 (95% CI, 0.49 to 0.65). The optimum Bohr cutoff value gave 100.0% sensitivity (95% CI, 84.5 to 100%) but a low specificity of 22.7% (95% CI, 18.8 to 27.2%). The optimum cutoff points for Enghoff and capillary Enghoff calculations gave sensitivities of 95.3% (95% CI, 77.3 to 99.2%) and 94.4% (95% CI, 74.2 to 99.0%), respectively, with poor specificity. CONCLUSIONS: Respiratory dead space analysis does not perform well as a stand-alone diagnostic test for pulmonary embolism in outpatients presenting with pleuritic chest pain.

Adult↗