D-Dimer test in cancer patients with suspected acute pulmonary embolism

BACKGROUND: The safety of a D-dimer (DD) measurement in cancer patients with clinically suspected pulmonary embolism (PE) is unclear. OBJECTIVES: The aim of this study was to assess the accuracy of the DD test in consecutive patients with clinically suspected PE with and without cancer. METHODS: The diagnostic accuracy of DD (Tinaquant D-dimer) was first retrospectively assessed in an unselected group of patients referred for suspected PE (n = 350). Subsequently, the predictive value of the DD was validated in a group of consecutive inpatients and outpatients with clinically suspected PE prospectively enrolled in a management study (n = 519). The results of the DD test in cancer patients were assessed according to the final diagnosis of PE and the 3-month clinical follow-up. RESULTS: In the first study group, DD showed a sensitivity and a negative predictive value (NPV) of 100% and 100% in patients with cancer and 97% and 98% in those without malignancy, respectively. In the validation cohort, the sensitivity and NPV of DD were both 100% (95% CI 82%-100% and 72%-100%, respectively), whereas in patients without malignancy, the corresponding estimates were 93% (95% CI 87%-98%) and 97% (95% CI, 95%-99%), respectively. The specificity of DD was low in patients with (21%) and without cancer (53%). CONCLUSIONS: A negative DD result safely excludes the diagnosis of PE in patients with cancer. Because of the low specificity, when testing 100 patients with suspected PE, a normal DD concentration safely excludes PE in 15 patients with cancer and in 43 patients without cancer.     

The VIDAS D-dimer test for venous thromboembolism: a prospective surveillance study shows maintenance of sensitivity and specificity when used in normal clinical practice

Background

As a result of a number of clinical management studies, D-dimer (DD) tests such as VIDAS (BioMérieux Australia P/L-Sydney, NSW) have been recommended to reduce venous thromboembolism (VTE) investigations. Surveillance studies for new tests are recommended. We prospectively assessed VIDAS DD in normal practice.

Methods

Consecutive emergency patients and inpatients (IPs) with DD or VTE investigations were prospectively identified. Investigation results and early chart review including predefined factors reducing specificity were documented. A latex DD was also performed. Patients were followed for at least 3 months for recurrent VTE.

Results

Four hundred three patients (emergency, 64%; VTE-positive, 12%; 95% followed up) were analyzed. VIDAS sensitivity was 96% (95% confidence interval 86%-99%), specificity 38% (confidence interval, 34%-44%; negative likelihood ratio, 0.11), and emergency specificity 51%. Latex sensitivity was 76%. Cancer, trauma, recent operations, IP status, and advanced age were associated with markedly reduced specificity. Specificity in older emergency patients (>70 years old) and younger IPs (<70) without comorbidities was 20% to 30%, but sensitivity was maintained at 100%.

Conclusions

VIDAS DD probably maintains adequate sensitivity in normal clinical practice for low- or even intermediate-risk patients. Latex agglutination had poor sensitivity. Specificity is best in younger low-morbidity emergency patients. These findings need validation in larger multicenter surveillance studies.     

Long-term opioid therapy for chronic noncancer pain: a systematic review and meta-analysis of efficacy and safety

Opioid therapy for chronic noncancer pain (CNCP) is controversial due to concerns regarding long-term efficacy and adverse events (including addiction). We systematically reviewed the clinical evidence on patients treated with opioids for CNCP for at least six months. Of 115 studies identified by our search of eleven databases (through April 7, 2007), 17 studies (patients [n]=3,079) met inclusion criteria. Studies evaluated oral (studies [k]=7; n=1,504), transdermal (k=3; n=1, 993), and/or intrathecal (k=8; n=177) opioids. Many patients withdrew from the clinical trials due to adverse effects (oral: 32.5% [95% confidence interval (CI), 26.1%-39.6%]; intrathecal: 6.3% [95% CI, 2.9%-13.1%]; transdermal: 17.5% [95% CI, 6.5%-39.0%]), or due to insufficient pain relief (oral: 11.9% [95% CI, 7.8%-17.7%]; intrathecal: 10.5% [95% CI, 3.5%-27.4%]; transdermal: 5.8% [95% CI, 4.2%-7.3%]). Signs of opioid addiction were reported in only 0.05% (1/2,042) of patients and abuse in only 0.43% (3/685). There was an insufficient amount of data on transdermal opioids to quantify pain relief. For patients able to remain on oral or intrathecal opioids for at least six months, pain scores were reduced long-term (oral: standardized mean difference [SMD] 1.99, 95% CI, 1.17-2.80; intrathecal: SMD 1.33, 95% CI, 0.97-1.69). We conclude that many patients discontinue long-term opioid therapy due to adverse events or insufficient pain relief; however, weak evidence suggests that oral and intrathecal opioids reduce pain long-term in the relatively small proportion of individuals with CNCP who continue treatment.     

Predictive values of triage temperature and pulse for antibiotic administration and hospital admission in elderly patients with potential infection

To determine how well triage temperature and pulse abnormalities in elderly patients with potential infections predict antibiotic administration and hospital admission. Data from the National Hospital Ambulatory Care Survey (2001-2002), a sample of US emergency departments, were used. Patients (>or=65 years) with a reason for visit suggesting potential infection were included. Of 10,586 patients 65 years or older, 32% had reasons for visit suggesting potential infection. The negative predictive value for predicting intensive care unit admission (n = 154) for triage hyperthermia (temperature >or=38 degrees C) was 96% (95% confidence interval, 95%-96%); hypothermia (temperature 相似文献   

MESOMARK: a potential test for malignant pleural mesothelioma

BACKGROUND: Soluble mesothelin-related peptides (SMRP)have been reported to be potential biomarkers for malignant pleural mesothelioma (MPM). We report analytical and preliminary clinical studies of MESOMARK, a quantitative assay for SMRP. METHODS: The MESOMARK assay is a 2-step immunoenzymatic assay in an ELISA format with a 6-point calibration curve (0-32 nmol/L). We assessed analytical imprecision, analyte stability, and analytical interferences. We measured SMRP by this assay in 409 apparently healthy individuals (reference interval study), 177 patients with nonmalignant conditions, and 500 cancer patients, including 88 with MPM. RESULTS: The limit of detection was 0.16 nmol/L. At 2-19 nmol/L, intraassay imprecision (CV) was 1.1%-5.3%, and total imprecision was 4.0%-11.0%. The mean dilution recovery for 5 samples was 109% (range, 99%-113%). No interference was seen from added bilirubin (200 mg/L), hemoglobin (500 mg/L), triglycerides (30 g/L), chemotherapeutic agents, or other tested substances. Recombinant mesothelin was stable in serum upon freeze/thaw at -70 degrees C and upon storage for at least 7 days at 2-8 degrees C. The 99(th) percentile of the reference group was 1.5 nmol/L [95% confidence interval (CI), 1.2-1.6 nmol/L; n = 409], and mean SMRP was significantly higher in sera from patients with MPM (7.5 nmol/L; 95% CI, 2.8-12.1 nmol/L; n = 88). SMRP was increased in 52% and 5% of MPM patients and asbestos-exposed individuals, respectively. Concentrations in other nonmalignant and malignant conditions were similar to those in healthy controls. CONCLUSIONS: The MESOMARK assay is analytically robust and may be useful for the detection and management of mesothelioma.     

Sensitivity and specificity of the semiquantitative latex agglutination D-dimer assay for the diagnosis of acute pulmonary embolism as defined by computed tomographic angiography

OBJECTIVE: To determine the sensitivity and specificity of the semiquantitative latex agglutination plasma fibrin D-dimer assay for the diagnosis of acute pulmonary embolism by using computed tomographic (CT) angiography as the diagnostic reference standard. PATIENTS AND METHODS: From January 1, 1998, to June 26, 2000, patients who had both semiquantitative latex agglutination plasma fibrin D-dimer testing and CT angiography for suspected acute pulmonary embolism were selected for the study. A D-dimer value greater than 250 ng/mL was considered positive for thromboembolic disease. Diagnosis of acute pulmonary embolism was based solely on the interpretation of the CT angiogram. The D-dimer assay results were then compared with the CT angiographic diagnoses. RESULTS: Of 946 CT studies, 172 (18%) were positive for acute pulmonary embolism. The D-dimer assay was positive for 612 (65%) of the 946 patients. For acute pulmonary embolism, the D-dimer assay had a sensitivity of 0.83 (95% confidence interval [CI], 0.76-0.88), a specificity of 039 (95% CI, 036-0.43), a negative likelihood ratio of 0.44 (95 % CI, 032-0.62), and a negative predictive value of 0.91 (95% CI, 0.87-0.94). CONCLUSIONS: The semiquantitative latex agglutination plasma fibrin D-dimer assay had moderate sensitivity and low specificity for the diagnosis of acute pulmonary embolism. When used alone, the results of this test were insufficient to exclude this serious and potentially fatal disorder. Approximately two thirds of our patients had positive D-dimer assays and required further evaluation to exclude acute pulmonary embolism.     

Diaphragm dysfunction detected with ultrasound to predict noninvasive mechanical ventilation failure: A prospective cohort study

ObjectiveThis study aimed to examine the use of point-of-care ultrasonography (POCUS) in detecting diaphragmatic dysfunction (DD) and evaluate its ability to predict noninvasive mechanical ventilation (NIV) failure in patients presented to the emergency department with acute exacerbation of chronic obstructive pulmonary disease (AECOPD).MethodsIn this prospective cohort study, the diaphragm was examined using POCUS in patients with AECOPD. DD was defined as a diaphragm thickening fraction of less than 20% during spontaneous breathing. NIV failure was the primary outcome of the study, and duration of hospital stay and in-hospital mortality were the secondary outcomes. Specificity, sensitivity, positive predictive value, and negative predictive value were estimated for predicting NIV failure in DD and evaluating the diagnostic performance of POCUS.Results60 patients were enrolled the study. NIV failure was found in 11 (73.3%) of 15 patients with DD and in 2 (4.4%) of 45 patients without DD. In predicting NIV failure, DD had a sensitivity of 84.6% (95% confidence interval [CI]:54.6–98.1), specificity of 91.5% (95% CI:79.6–97.6), positive predictive value of 73.3% (95% CI:51.2–87.8), and negative predictive value of 95.6% (95% CI:85.7–98.7). The duration of hospital stay was not different between groups (p = .065). No in-hospital mortality was seen in patients without DD.ConclusionsDD has high sensitivity and specificity in predicting NIV failure in patients admitted to the emergency department with AECOPD. DD can be assessed by an experienced clinician noninvasively using POCUS in emergency departments.     

Plasma DNA as a prognostic marker in trauma patients

BACKGROUND: Recently, much interest has developed in the potential use of plasma DNA as a diagnostic and monitoring tool. We hypothesized that plasma DNA is increased in patients with trauma and may be prognostic in such patients. METHODS: We studied 84 patients who had sustained an acute blunt traumatic injury. We measured plasma DNA by a real-time quantitative PCR assay for the beta-globin gene. Blood samples were collected at a median time of 60 min following injury. Blood samples were also obtained from 27 control subjects. RESULTS: The median plasma DNA concentrations in the control, minor/moderate trauma (Injury Severity Score <16; n = 47), and major trauma (Injury Severity Score > or =16; n = 37) groups were 3154 kilogenome-equivalents/L, 13 818 kilogenome-equivalents/L, and 181 303 kilogenome-equivalents/L, respectively. Plasma DNA concentrations in patients with adverse outcomes, including acute lung injury, acute respiratory distress syndrome, and death, had 11. 6- to 12-fold higher plasma DNA concentrations than those who did not develop these complications. At a cutoff of 232 719 kilogenome-equivalents/L, the sensitivities of plasma DNA analysis for the prediction of acute lung injury, acute respiratory distress syndrome, and death were 100% (95% confidence interval, 100-100%), 100% (95% confidence interval, 100-100%), and 78% (95% confidence interval, 40-97%), respectively. The respective specificities were 81% (95% confidence interval, 71-89%), 80% (95% confidence interval, 70-88%), and 82% (95% confidence interval, 71-90%). CONCLUSIONS: Plasma DNA is increased after trauma and may be a potentially valuable prognostic marker for these patients.     

Rapid diagnosis of acute bacterial meningitis: role of a broad range 16S rRNA polymerase chain reaction

Background: Acute bacterial meningitis is a significant cause of morbidity and mortality throughout the world. It can be difficult to diagnose, as the symptoms and signs are often non-specific. Study Objective: To evaluate the performance of an in-house semi-nested polymerase chain reaction (PCR) assay targeting the 16S rRNA gene of Eubacteria for the rapid diagnosis of acute bacterial meningitis using cerebrospinal fluid (CSF) specimens. Methods: A total of 112 CSF samples from 112 patients were used in the study. Among these, 32 samples were obtained from confirmed cases of Streptococcus pneumoniae, six samples were obtained from confirmed cases of Haemophilus influenzae, one sample from a confirmed case of Neisseria meningitidis, and 10 cases of clinically suspected acute bacterial meningitis. The remaining 63 CSF samples were obtained from patients with non-infectious illnesses (n = 47) of the central nervous system (CNS) and autopsy-confirmed tuberculous meningitis (n = 16). Results: The assay had an overall sensitivity of 93% (95% confidence interval [CI] 0.81–0.98, negative predictive value = 95%) and a specificity of 98% (95% CI 0.92–1.0, positive predictive value = 98%). Conclusion: These preliminary findings suggest that the semi-nested PCR assay targeting the 16S rRNA gene may be used as a rapid test for the diagnosis of acute bacterial meningitis.     

Assessment of the pulmonary embolism rule-out criteria rule for evaluation of suspected pulmonary embolism in the emergency department

Background

Overuse of resources when evaluating pulmonary embolism (PE) is a concern if the D-dimer assay is improperly used in the evaluation of emergency department patients with suspected PE. The pulmonary embolism rule-out criteria (PERC) rule was derived to prevent unnecessary diagnostic testing in this patient population. The objective of this study was to assess the PERC rule's performance in an external population.

Methods

This was a secondary analysis of a prospectively collected database comparing PERC rule variables to diagnosis of PE in consecutive patients with suspicion for PE. Bivariate analysis on individual variables and the overall accuracy of the PERC rule were performed.

Results

Patients on 120 randomly assigned shifts were enrolled with a PE prevalence of 12%. The sensitivity, specificity, positive predictive, and negative predictive values of the PERC rule were 100% (95% confidence interval [CI], 79%-100%), 16% (95% CI, 10%-24%), 14% (95% CI, 8%-14%), and 100% (95% CI, 80%-100%), respectively, for the total patient population, and 100% (95% CI, 25%-100%), 33% (95% CI, 12%-35%), 2% (95% CI, 0%-11%), and 100% (95% CI, 75%-100%), respectively, for the low pretest probability population. Bivariate analysis showed unilateral leg swelling, recent surgery, and a history of venous thromboembolic event to be predictive of the diagnosis of PE.

Conclusions

The PERC rule may identify a cohort of patients with suspected PE for whom diagnostic testing beyond history and physical examination is not indicated.     

Predictive value of a rapid semiquantitative D-dimer assay in critically ill patients with suspected venous thromboembolic disease

OBJECTIVE: To evaluate the performance of a new, rapid semi-quantitative assay for the detection of circulating D-dimer in whole blood from critically ill patients with suspected venous thromboembolic disease. DESIGN: Prospective, blinded, single-center study. SETTING: Medical intensive care unit (ICU) of Barnes-Jewish Hospital, St. Louis, MO, a university-affiliated urban teaching hospital. PATIENTS: Two hundred thirty-nine adult patients with clinical suspicion of venous thromboembolic disease admitted to a medical ICU. INTERVENTIONS: Collection of blood samples within 24 hrs of clinical suspicion of venous thromboembolic disease. MEASUREMENTS AND MAIN RESULTS: The main outcome measures evaluated included the occurrence of venous thromboembolic disease (i.e., lower extremity venous thrombosis, pulmonary embolism, catheter-associated venous thrombosis) and hospital mortality. Fifty-seven patients (23.8%) were classified as having venous thromboembolic disease during their ICU stays (pulmonary embolism, 21 patients; lower extremity thrombosis, 44 patients; line-associated venous thrombosis, 3 patients). The semiquantitative whole-blood assay for circulating D-dimer had a 96.4% sensitivity and a negative predictive value of 92.1% for identifying patients with venous thromboembolic disease. The specificity of this assay was 19.7%, and its positive predictive value was 26.9%. There was a strong correlation between the semiquantitative assay for circulating D-dimer and the quantitative measurement of circulating D-dimer using an enzyme immunoassay (Spearman's correlation coefficient, 0.8643; p<.001). We also identified a strong correlation between both the quantitative and semiquantitative measurements of circulating D-dimer with the sepsis classification proposed by the American College of Chest Physicians/Society of Critical Care Medicine (i.e., systemic inflammatory response syndrome, sepsis, severe sepsis, septic shock) for patients without venous thromboembolic disease (n = 182; quantitative measure: Spearman's correlation coefficient, 0.207; p = .002; semiquantitative measure: Spearman's correlation coefficient, 0.3519; p<.001). CONCLUSIONS: These preliminary findings suggest that a rapid whole-blood assay for the semiquantitative detection of circulating D-dimer may be a useful diagnostic tool for the exclusion of venous thromboembolic disease among critically ill patients.     

Arterial Blood Gas Results Rarely Influence Emergency Physician Management of Patients with Suspected Diabetic Ketoacidosis

OBJECTIVES: To test the hypothesis that arterial blood gas (ABG) results for patients with suspected diabetic ketoacidosis (DKA) do not influence emergency physicians' management decisions and to assess correlation and precision between venous pH and arterial pH. METHODS: Prospective, observational study of emergency physicians' decision making for consecutive ED patients with suspected DKA. Inclusion criteria were capillary blood glucose equal to or greater than 200 mg/dL, ketonuria, and clinical signs and symptoms of DKA. Venous pH, chemistry panel, and ABGs were drawn before treatment. Attending emergency physicians indicated planned management and disposition on a standardized form before and after reviewing ABG and venous pH results. This study was powered to detect a 10% difference in management decisions (n = 195). Pearson's correlation and Bland-Altman bias plot were used to compare venous pH and arterial pH. RESULTS: ABG analysis changed the emergency physicians' diagnosis in 2/200 cases (1.0%; 95% confidence interval [95% CI] = 0.3% to 3.6%), altered treatment in 7/200 cases (3.5%; 95% CI = 1.7% to 7.1%), and changed disposition in 2/200 cases (1.0%; 95% CI = 0.3% to 3.6%). The pH value of the ABGs changed the treatment or disposition in 5/200 patients (2.5%; 95% CI = 1.1% to 5.7%). The Po(2) and Pco(2) results of the ABGs altered treatment and disposition in 2/200 patients (1.0%; 95% CI = 0.3% to 3.6%). Venous pH correlated well with arterial pH (r = 0.951), and bias plotting yielded a bias value of -0.015 (+/- 0.006 pH units). CONCLUSIONS: ABG results rarely influenced emergency physicians' decisions on diagnosis, treatment, or disposition in suspected DKA patients. Venous pH correlated well and was precise enough with arterial pH to serve as a substitute.     

Angiotensin converting enzyme DD genotype is associated with hypertensive crisis

OBJECTIVE: The genetic background of hypertensive crisis is unknown. We examined the association of polymorphisms in genes involved in the renin-angiotensin-aldosterone-system with hypertensive crisis. DESIGN: Population-based case-control study. SETTING: Emergency department at a tertiary care university hospital. PATIENTS: A total of 182 patients with essential hypertension who were admitted to an emergency department for treatment of hypertensive crisis and 182 age- and sex-matched healthy individuals. INTERVENTIONS: None. MEASUREMENTS: Analysis of polymorphisms in genes coding for angiotensinogen (AJT 704T-->C), angiotensin II receptor 1 (AGTR1 1166A-->C), renin (REN 2646G-->A), renin-binding protein (RENBP 61T-->C), alpha-adducin (ADD1 1378G-->T), beta-2-adrenergic receptor (ADRB2 46A-->G, 79C-->G), and angiotensin I converting enzyme (ACE I/D) was performed by polymerase chain reaction and restriction fragment length polymorphism analysis.MAIN RESULTS Among patients, the ACE I/D polymorphism showed a deviation from Hardy-Weinberg equilibrium (p =.01). In controls, all polymorphisms were in the Hardy-Weinberg equilibrium. The frequency of the DD genotype was increased in patients (n = 70, 38.5%) vs. controls (n = 51; 28.0%;p =.03; odds ratio, 1.61; 95% confidence interval, 1.03-2.50), which was due to the DD genotype in 40 male patients (44%) vs. 23 in male controls (25.3%;p =.004; odds ratio, 3.48; 95% confidence interval, 1.47-8.30). There were no differences in genotype distributions among other polymorphisms. CONCLUSION: We demonstrate a possible association of the DD genotype with hypertensive crisis in men.     

High maternal blood S100B concentrations in pregnancies complicated by intrauterine growth restriction and intraventricular hemorrhage

BACKGROUND: Intrauterine growth restriction (IUGR) is associated with perinatal mortality and with neurologic damage from intraventricular hemorrhage (IVH). We investigated whether S100B, a neural protein found in high concentrations after cell injury in the nervous system, is increased in serum of women whose pregnancies are complicated by IUGR and whose newborns develop IVH. We also explored the prognostic accuracy of maternal serum S100B for IVH in the newborn. METHODS: We conducted a case-control study of 106 pregnancies complicated by IUGR, including a subgroup (n = 26) who developed IVH after birth, and 212 unaffected pregnancies matched for gestational age. Ultrasound examination, Doppler velocimetry patterns (in the utero-placental vessels and middle cerebral artery), and maternal blood collection were performed before birth; cerebral ultrasound and neurologic examinations were performed after birth. RESULTS: S100B was higher (P <0.001) in IUGR pregnancies complicated by IVH than in those that were not and in controls. At a cutoff of 0.72 microg/L, sensitivity was 100% [95% confidence interval (95% CI), 87%-100%] and specificity was 99.3% (97.5%-99.9%) for prediction of IVH (area under the ROC curve, 0.999). The prevalence of IVH was 8.2% in the whole study population, 93% (95% CI, 83.6%-100%) in those with maternal S100B >0.72 microg/L, and 0% (0%-2.5%) in those with maternal S100B <0.72 microg/L. CONCLUSION: For prediction of IVH, measurements of maternal S100B may be useful at times before clinical, laboratory, and ultrasound patterns can identify risk of IVH.     

Association study of the I/D polymorphism and plasma angiotensin-converting enzyme (ACE) as risk factors for stent restenosis

The ID (insertion/deletion) polymorphism of the ACE (angiotensin-converting enzyme) gene controls plasma ACE levels. Both have been correlated with ISR (in-stent restenosis) in preliminary analyses, but not confirmed in larger studies. In the present study, baseline and 6-month quantitative coronary analysis were performed in 897 patients who had stent implantation and the ID polymorphism genotyped. Plasma ACE levels were measured in 848 patients (95%). Restenosis rates among genotypes were 31.2% DD, 25.5% ID and 28.8% II (not significant). Plasma ACE levels were significantly higher in restenotic patients compared with patients without restenosis (30.7+/-18.6 units/l compared with 22.8+/-12.8 units/l; P=0.0001) and a strong independent predictor of ISR [OR (odds ratio)=3.70; 95% CI (confidence interval), 2.40-5.71; P<0.0001], except in diabetics. In the subgroup of diabetics and patients with AMI (acute myocardial infarction), the DD genotypes actually had a lower risk of ISR than the II genotypes (diabetics, OR=0.16; 95% CI, 0.04-0.69; P=0.014; and patients with AMI, OR=0.21; 95% CI, 0.061-0.749; P=0.016). After exclusion of diabetics and patients with AMI, ISR rates for genotypes in 632 patients were 31.7% DD, 24.3% ID and 17.6% II (P=0.02; DD compared with non-DD OR=1.57; 95% CI, 1.09-2.25). The association between the D allele and ISR observed in selected populations does not hold with a larger sample size. Other than sample size, clinical variables can modulate the association between ID polymorphism and ISR. Plasma ACE level is a risk factor for ISR, independently of the ID genotype.     

Evaluation of color Doppler ultrasonography in diagnosing hepatic alveolar echinococcosis

To assess the accuracy of color Doppler ultrasonography in diagnosing hepatic alveolar echinococcosis, 129 patients were examined at the First Affiliated Hospital of Xinjiang Medical University between July 2004 and June 2010. Those patients suspected of having hepatic alveolar echinococcosis were examined and diagnosed by color Doppler ultrasound. All the cases were compared with the gold standard. The findings of their sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, negative likelihood ratio and 95% confidence interval were recorded. Sensitivity: 95% (95% confidence interval: 90.7%-99.3%); specificity: 20.7% (95% confidence interval: 6.0%-35.4%); positive predictive value: 80.5%; negative predictive value: 54.5%; positive likelihood ratio: 1.2: negative likelihood ratio: 0.2. Our study indicates that color Doppler ultrasonography, when used in diagnosing hepatic alveolar echinococcosis, has high sensitivity although specificity is low. Color Doppler ultrasound is, thus, considered to be an efficient means for diagnosing hepatic alveolar echinococcosis.     

Effect of ketoconazole on ritonavir and saquinavir concentrations in plasma and cerebrospinal fluid from patients infected with human immunodeficiency virus

AIM: Our aim was to evaluate the effect of ketoconazole on ritonavir and saquinavir plasma and cerebrospinal fluid (CSF) concentrations. METHODS: Twelve patients who were human immunodeficiency virus-seropositive and who were receiving 400 mg of ritonavir and 400 mg of saquinavir twice daily completed a nonfasted, two-period, two-group, longitudinal pharmacokinetic study. Blood samples were collected over the daytime 12-hour dosing interval of the protease inhibitors at baseline (period 1, day 0) and after 10 days of coadministration of 200 mg (n = 6) or 400 mg (n = 6) of ketoconazole once daily (period 2, day 10). One set of paired CSF and blood samples was collected between 4 and 5 hours after the dose on both days. RESULTS: Ketoconazole significantly increased area under the plasma concentration-time curve, plasma concentration at 12 hours after the dose, and half-life of ritonavir by 29% (95% confidence interval (CI), 13%-46%), 62% (95% CI, 37%-92%), and 31% (95% CI, 13%-51%), respectively. Similar increases of 37% (95% CI, 4%-81%), 94% (95% CI, 41%-167%), and 38% (95% CI, 15%-66%), respectively, were observed for these parameters for saquinavir. Ketoconazole significantly elevated ritonavir CSF concentration by 178% (95% CI, 59%-385%), from 2.4 to 6.6 ng/mL, with no change in paired unbound plasma level (26 ng/mL); this led to a commensurate 181% increase (95% CI, 47%-437%) in CSF/plasma unbound ratio. All pharmacokinetic changes were unrelated to ketoconazole dose or plasma exposures. Corresponding changes for saquinavir CSF pharmacokinetics were insignificant (P > .06); saquinavir CSF levels were unmeasurable in 7 patients (<0.2 ng/mL). Conclusions: The disproportionate increase in CSF compared with plasma concentrations of ritonavir is consistent with ketoconazole inhibiting both drug efflux from CSF and systemic clearance.     

A model for predicting delay in discharge of stroke patients.

AIMS: To study the factors that predict delay in discharge (DD) for stroke victims when they are admitted to hospital and to build a model for predicting DD in our hospital. METHOD: A retrospective study of 214 stroke victims admitted to the Physical Medicine and Rehabilitation Service (PMRS) of a general hospital between January 1, 1994, and December 31, 2001. Seventeen clinical and sociodemographic data were studied to determine which factors were predictors of DD: age, sex, type of stroke, side affected, sphincter control, ability to communicate, level of consciousness, deep sensitivity, antecedents of cardiovascular risk, delay before admission to the PMRS, initial functional state and solitude, whether the patient was employed prior to the cerebrovascular accident, and whether the patient's place of residence had any exterior architectural barriers. RESULTS: A total of 26.6% of patients experienced DD. Factors influencing DD were solitude (odds ratio [OR] 6; 95% confidence interval [CI] 2.2-16.1), an initial functional independence measure (FIM) below 50 (OR 4.5; 95% CI 2.3-8.9) and age greater than 75 years (OR 2.7; 95% CI 1.2-6.1). The best model for predicting DD comprises seven variables: solitude, initial FIM below 50, older than 75 years, left hemiparesis, exterior architectonic barriers at home, cardiovascular antecedents and sex (male). This model has a specificity of 89% and a sensitivity of 40%. CONCLUSION: Solitude, low initial FIM and age older than 75 years influence DD for patients with stroke admitted to hospital. A model for predicting DD is described.     

Venous vs arterial blood gases in the assessment of patients presenting with an exacerbation of chronic obstructive pulmonary disease

Objective

The purpose of this study was to investigate the clinical correlation between arterial and venous blood gas (VBG) values in patients presenting to the emergency department (ED) with acute exacerbation of chronic obstructive pulmonary disease.

Methods

A prospective study of patients with chronic obstructive pulmonary disease presenting to the ED with acute ventilatory compromise was done. Patients were included if their attending physician considered arterial blood gas sampling important in their initial assessment. Data from arterial and venous samples were compared using Spearman correlation and bias plot (Bland-Altman) methods.

Results

Ninety-four patients were enrolled in the study. Eighty-nine patients had complete data sets for analysis. Arterial hypercarbia was present in 30 patients (33.7%; range, 51-140.19 mm Hg). All cases of arterial hypercarbia were detected using VBG sampling when a screening cutoff of 45 mm Hg was applied (sensitivity, 100%; 95% confidence interval, 88.7%-100% and specificity, 34%; 95% confidence interval, 23.1%-46.6%). Bias plot revealed moderate agreement between arterial and venous Pco₂ with an average difference of 8.6 mm Hg and 95% limits of agreement of −7.84 to 25.05 mm Hg. For pH, mean difference between each group was 0.039 (range, −0.12 to 0.03). Linear regression analysis for pH demonstrated very close equivalence with a regression coefficient of 0.955, and Spearman correlation showed significant correlation of 0.826 (P = .001).

Conclusion

Venous pH and HCO₃ values show excellent correlation with arterial values. Using a previously validated screening cutoff of 45 mm Hg, venous CO₂ has 100% sensitivity in detecting arterial hypercarbia. There is insufficient agreement between venous and arterial CO₂ for VBG to replace arterial blood gas in determining the degree of hypercarbia.