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D L Simel

Publications and source records attributed to D L Simel.

72 records · Page 4Linked to original sources
PubMed1987

Correction of hypoprothrombinemia by immunosuppressive treatment of the lupus anticoagulant-hypoprothrombinemia syndrome.

A 66-year-old man with the lupus anticoagulant-hypoprothrombinemia syndrome was treated with cyclophosphamide and prednisone to correct a factor II deficiency prior to elective major surgery. Whereas the lupus anticoagulant activity persisted, functional factor II levels normalized and he underwent surgery without a bleeding diathesis. Immunosuppressive therapy may temporarily normalize factor II levels in patients with the lupus anticoagulant-hypoprothrombinemia syndrome and reduce the risk of excessive hemorrhage. The disparate response of the lupus anticoagulant and hypoprothrombinemia to immunosuppression suggests that the lupus anticoagulant did not directly cause the hypoprothrombinemia.

Aged↗
PubMed1987

Cold hemagglutinin disease in the operating room.

Cold hemagglutinin disease is infrequently recognized before complications ensue. We describe a patient with chronic cold hemagglutinin disease who sustained an acute hemolytic crisis during a routine operative procedure in a cool operating room. Cold agglutinins were present during routine preoperative blood cross matching with the Coombs' test positive for C3d. Analysis of the offending cold agglutinin revealed a high-titer monoclonal IgM-kappa antibody with anti-I specificity and broad thermal amplitude. Major complications from the presence of cold agglutinins have been poorly documented and are often thought to be of only theoretic concern. This case and literature review show that such complications may occur and emphasize the importance of careful preoperative plans when the Coombs' test suggests that cold agglutinins exist.

Aged↗
PubMed1987

Quantitative approaches to clinical diagnosis of cancer in elderly patients.

Recommendations for cancer detection in the elderly are based on even less evidence of efficacy than are recommendations for the general adult population. In this article, we present some quantitative measures of test performance--operating characteristics, effectiveness and cost effectiveness/cost benefit--and show examples of how to use these measures to adjust diagnostic strategies for factors especially relevant to the elderly.

Aged↗
PubMed1987

Who should have intravenous pyelograms before hysterectomy for benign disease?

A review of 493 cases was undertaken to identify which patients undergoing hysterectomy for benign disease had received a preoperative intravenous pyelogram (IVP), an abnormality identified by IVP, and intraoperative ureteral injuries. Intravenous pyelograms were performed on 299 patients (60.6%). Factors significantly associated with obtaining a preoperative IVP included an abdominal approach, uterine size of 12 weeks or greater, and uterine prolapse. Seventy-seven patients (27%) had an abnormal IVP; factors likely to be associated with abnormality included uterine size of 12 weeks or larger or an adnexal mass of 4 cm or larger. Endometriosis, pelvic inflammatory disease, pelvic relaxation, and previous intra-abdominal surgery were not associated with an increased prevalence of abnormal IVP findings. Two ureteral injuries were documented, one in the IVP group (0.3%) and one in the non-IVP group (0.5%). Clinical findings may be used to select for a preoperative IVP those patients who are likely to have abnormalities of importance to the pelvic surgeon.

Adult↗
PubMed1985

Playing the odds.

Explore the source record for details and available documents.

Bayes Theorem↗
PubMed1985

Leukemic ascites complicating acute myelomonoblastic leukemia.

We describe a patient with acute myelomonoblastic leukemia, jaundice, and ascites. The ascitic fluid contained leukemic cells comparable with those of the blood and bone marrow. Treatment with cytarabine (cytosine arabinoside) caused a decrease in the peripheral blood blast cell count and the serum bilirubin level, but the leukemic ascites did not change. Ascites in patients with acute leukemia must be examined to differentiate leukemic infiltration from other causes such as infection.

Ascites↗
PubMed1984

Scanning electron microscopic study of the airways in normal children and in patients with cystic fibrosis and other lung diseases.

Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to examine pulmonary tissue from 9 patients with cystic fibrosis (CF), 12 patients with diseases other than CF, and from two surgically resected specimens with no known airways disease. A region of the human airways, the transition zone, was observed between the end of the terminal bronchiole and the type II alveolar cell lining of the respiratory bronchioles. This region was lined predominantly by nonciliated bronchiolar (NCB) cells. Patients with CF exhibited indistinct transition zones, epidermoid metaplasia, large dilated bronchial glands, copious surface mucus, alveolar destruction, and unusual microvilli; no single lesion specific for cystic fibrosis was identified.

Adolescent↗
PubMed1984

Is streptokinase safe during menses?

We used intravenous streptokinase to treat a young woman with deep venous thrombosis manifested during her menses. There was no increase in menstrual bleeding, and she was symptom free six months later. Because menstrual endothelium after the first day of menses relies on arteriolar constriction for hemostasis rather than the formation of fibrin, we think that streptokinase may not be contraindicated in thrombotic disorders that occur during menses after the first day.

Adult↗
PubMed1981

The prevalence of abnormal cilia in normal pediatric lungs.

Abnormal respiratory cells have been reported in cases of chronic pediatric respiratory infection. In some cases, there is a specific defect of most cilia, but in others there is a variety of derangements of the architecture of only a fraction of the cilia. Histologically normal lungs from two children without known respiratory disease were examined and found to contain many abnormal cilia of the polymorphic type, which accounted for 3% to 5% of all cilia. Abnormalities included (1) excess cytoplasmic matrix, (2) additions, deletions, or aberrant arrangements of the 9 + 2 tubular pattern, (3) multiple partial or complete cilia within one membrane, and (4) occasional marked disorganization of all cilia in a cell. Polymorphic ciliary abnormalities may be common in healthy children, and should be cautiously interpreted as a cause of chronic respiratory infection.

Child↗
PubMedDate not supplied

Diagnostic efficiency of home pregnancy test kits. A meta-analysis.

OBJECTIVE: To assess the diagnostic efficiency of home pregnancy test (HPT) kits. DATA SOURCES: A literature search of English-language studies was performed with MEDLINE and a review of bibliographies. STUDY SELECTION: Studies were included if HPT kits were compared with a criterion standard (laboratory testing), if they used appropriate controls, and if data were available to determine sensitivity and specificity. DATA EXTRACTION: Two investigators independently extracted data, and disagreement was resolved by consensus. Sensitivity, specificity, and an effectiveness score (a measure of the discriminatory power of the test, with higher scores implying greater effectiveness) were calculated. DATA SYNTHESIS: Five studies evaluating 16 HPT kits met the inclusion criteria. The range of sensitivities for HPT kits was 0.52 to 1.0. In studies where urine samples obtained by the investigators were tested by volunteers, sensitivity was 0.91 (95% confidence interval [CI], 0.84-0.96). However, the sensitivity was less in studies where subjects were actual patients who performed the test on their own urine samples (sensitivity, 0.75 [95% CI, 0.64-0.85]). The test effectiveness score was 2.75 (95% CI, 2.3-3.2) for studies where subjects were volunteers but deteriorated to 0.82 (95% CI, 0.4-1.2) for studies with actual patients. CONCLUSIONS: The diagnostic efficiency of HPT kits is greatly affected by characteristics of the users. Despite the popularity of these kits, the relatively low effectiveness scores of these kits when used by actual patients are of concern. We suggest that manufacturers of HPT kits publish results of trials in actual patients before marketing them to the general public.

Female↗
PubMedDate not supplied

Cranial computed tomography before lumbar puncture: a prospective clinical evaluation.

OBJECTIVE: To prospectively identify which patients can safely undergo lumbar puncture (LP) without screening cranial computed tomography (CT). METHODS: Emergency department physicians examined patients before CT. Examiners recorded the presence or absence of 10 clinical findings and answered 8 additional questions. The criterion standard was noncontrast cranial CT interpreted by staff radiologists. Clinical findings were prospectively compared with those of CT. RESULTS: One hundred thirteen consecutive adults with the urgent need for LP (median age, 42 years) were studied. Fifteen percent of patients meeting entrance criteria had new CT-documented lesions, with 2.7% having lesions that contraindicated LP. Sensitivity, specificity, and likelihood ratios (LRs) were measured for the clinical findings. Three statistically significant predictors of new intracranial lesions were identified: altered mentation (positive LR, 2.2; 95% confidence interval [CI], 1.5-3.2), focal neurologic examination (positive LR, 4.3; 95% CI, 1.9-10), and papilledema (positive LR, 11.1; 95% CI, 1.1-115). No single item adequately predicted the absence of CT abnormalities, but the clinical screening items in aggregate significantly predicted the results (negative LR, 0; upper 95% confidence limit, 0.6). The overall clinical impression had the highest predictive value in identifying patients with CT-defined contraindications to LP (positive LR, 18.8; 95% CI, 4.8-43). CONCLUSIONS: Because of the low prevalence of lesions that contraindicate LP, screening cranial CT solely to establish the safety of performing an LP typically provides limited additional information. Physicians can use their overall clinical impression and 3 clinical predictors to identify patients with the greatest risk of having intracranial lesions that may contraindicate LP.

Adult↗
PubMedDate not supplied

Quantitating bedside diagnosis: clinical evaluation of ascites.

The authors prospectively evaluated the operating characteristics of the history and physical examination for ascites in a broad spectrum of hospitalized patients. The overall clinical evaluation produced a positive likelihood ratio = 37.7-83.3 when suggestive of ascites, a likelihood ratio = 2.23-3.42 when intermediate, and a negative likelihood ratio = 0.77-0.90 when not suggestive of ascites. Patients' perceptions of increased abdominal girth (positive likelihood ratio = 4.16) or recent weight gain (positive likelihood ratio = 3.20) increased the likelihood of ascites. The absence of subjective ankle swelling (negative likelihood ratio = 0.10) or increased abdominal girth (negative likelihood ratio = 0.17) decreased the likelihood of ascites. The positive likelihood ratios for a fluid wave = 9.6 and shifting dullness = 5.76 favored ascites, while the absence of bulging flanks (negative likelihood ratio = 0.12) or peripheral edema (negative likelihood ratio = 0.17) favored ascites the least. Thus, a routine history and physical examination are quantitatively useful in the clinical evaluation of ascites.

Ascites↗
PubMedDate not supplied

Diagnosing sinusitis by X-ray: is a single Waters view adequate?

OBJECTIVE: To determine whether a single Waters view (occipito-mental) radiograph could be substituted for a four-view sinus series to diagnose sinusitis, and to determine the inter- and intraobserver variabilities for sinus radiography. DESIGN: Radiographs were interpreted by radiologists blinded to the clinical history, and results were recorded on a standardized form. SETTING: Veterans Affairs Medical Center. PARTICIPANTS: Staff attending radiologists, an attending radiologist with special training in skull radiology, and a senior radiology resident. MEASUREMENTS AND MAIN RESULTS: The agreement between the Waters view and the four-view sinus series was moderate to substantial (simple agreement = 75-84%, kappa = 0.5-0.68). However, agreement varied by sinus and, after correction for chance agreement, was substantial only for the maxillary sinuses (kappa = 0.72-0.87). Intraobserver agreement (kappa = 0.72-0.84) was superior to interobserver agreement (kappa = 0.49-0.59) for the four-view sinus series. CONCLUSIONS: Substituting a single Waters view for a four-view sinus series may be an acceptable strategy for diagnosing maxillary sinusitis.

Adult↗
PubMedDate not supplied

Intermediate, indeterminate, and uninterpretable diagnostic test results.

Diagnostic tests do not always yield positive or negative results; sometimes the results are intermediate, indeterminate, or uninterpretable. No consensus exists for the incorporation of such results into data assessment. Conventional Bayesian analysis leads investigators to either exclude patients with non-positive, non-negative results from their studies or categorize such results into inappropriate cells of the standard four-cell decision matrix. The authors propose a standardized method for reporting results in studies dealing with diagnostic test use and discuss how researchers should expand the four-cell matrix to six cells when non-positive, non-negative results occur. They suggest that the six-cell matrix with new operational definitions of sensitivity, specificity, likelihood ratios, and test yield should be adopted routinely. In addition, they define the different types of non-positive, non-negative results and demonstrate how clinicians can use tree-structured decision analysis from the six-cell matrix. While their method does not solve all problems posed by non-positive, non-negative results, it does suggest a standard method for reporting these results and utilizing all the data in decision making.

Bayes Theorem↗
PubMedDate not supplied

A Bayesian method for evaluating medical test operating characteristics when some patients' conditions fail to be diagnosed by the reference standard.

The evaluation of a diagnostic test when the reference standard fails to establish a diagnosis in some patients is a common and difficult analytical problem. Conventional operating characteristics, derived from a 2 x 2 matrix, require that tests have only positive or negative results, and that disease status be designated definitively as present or absent. Results can be displayed in a 2 x 3 matrix, with an additional column for undiagnosed patients, when it is not possible always to ascertain the disease status definitively. The authors approach this problem using a Bayesian method for evaluating the 2 x 3 matrix in which test operating characteristics are described by a joint probability density function. They show that one can derive this joint probability density function of sensitivity and specificity empirically by applying a sampling algorithm. The three-dimensional histogram resulting from this sampling procedure approximates the true joint probability density function for sensitivity and specificity. Using a clinical example, the authors illustrate the method and demonstrate that the joint probability density function for sensitivity and specificity can be influenced by assumptions used to interpret test results in undiagnosed patients. This Bayesian method represents a flexible and practical solution to the problem of evaluating test sensitivity and specificity when the study group includes patients whose disease could not be diagnosed by the reference standard.

Algorithms↗