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C Schroder

Publications and source records attributed to C Schroder.

10 recordsLinked to original sources
PubMed2004

High hepatitis B virus (HBV) DNA viral load is an important risk factor for HBV reactivation in breast cancer patients undergoing cytotoxic chemotherapy.

Hepatitis B virus (HBV) reactivation during cytotoxic chemotherapy for cancer may complicate treatment and cause liver damage. The complication has been reported to occur in 10% to over 50% of HBV carriers, but the factors that determine which patients will develop reactivation remain unclear. The objective of the study is to test the hypothesis that the prechemotherapy HBV DNA level is a risk factor for the development of HBV reactivation. We studied 41 women undergoing cytotoxic chemotherapy for breast cancer, 17 of whom developed reactivation and 24 who did not. We developed a novel, ultra-sensitive, real-time polymerase chain reaction assay for the measurement of HBV DNA. The sera of 37 patients (16 who developed reactivation and 21 who did not) were available for measurement of HBV DNA using this technique. The results showed that patients in the reactivation group had a significantly higher median HBV DNA load (1.03 x 10(6) copies/mL; range <2.9 x 10(3) to 8.723 x 10(7)) than did the nonreactivation group (<2.9 x 10(3) copies/ml; range <2.9 x 10(3) to 6.331 x 10(7)) (P < 0.001). The optimal cut-off between the two groups was found to be at serum HBV DNA level of 3 x 10(5), which gave a sensitivity of 81.0% and a specificity of 85.0%. In conclusion, for breast cancer patients receiving standard cytotoxic chemotherapy, a high HBV viral load prior to the administration of cytotoxic chemotherapy is a significant predictive factor for the development of HBV reactivation. Such information may be useful in determining which patients would benefit most from prophylactic antiviral therapy during cytotoxic chemotherapy.

Antineoplastic Agents↗
PubMed2001

IgA antibodies against endomysium and transglutaminase: a comparison of methods.

Recently, the endomysial antigen has been identified as the protein cross-linking enzyme known as tissue transglutaminase (tTG). Our objective was to compare a novel enzyme immunoassay (EIA) that detects IgA antibody against tTG to two standard IFA methods utilizing thin tissue sections of rat kidney/rat stomach (KS) and distal primate esophagus (PE) as substrates to detect IgA antibody against endomysium (EMA). Sera from 100 patients suspected of having gluten-sensitive enteropathy (GSE) and 23 sera possessing various antibodies used for EIA cross-reactivity studies were included. Additional tests, performed routinely in our laboratory, were utilized to further assess sera from patients suspected having GSE. These tests include anti-gliadin IgA antibody (AGA) and anti-reticulin IgA antibody (ARA) and are part of the European Society for Pediatric Gastroenterology and Nutrition (ESPGAN) revised criteria for diagnosing GSE. When compared to IFA using KS, the tTG EIA had a sensitivity of 87.5%, was 97.1% specific, and had an overall agreement of 94.0%. When compared to IFA using PE, the tTG EIA had a sensitivity of 92.6%, was 93.2% specific, and had an overall agreement of 93.0%. When the KS IFA was compared to the PE IFA for EMA, the KS IFA had a sensitivity of 96.3%, was 91.8% specific, and had an overall agreement of 93.0%. The majority of sera that were positive for tTG but were negative by IFA (KS, n = 2/PE, n = 5) possessed IgA antibodies against gliadin and/or reticulin. Five of six sera with negative results by PE IFA were positive by the KS IFA and possessed one or more antibodies to tTG and/or gliadin and/or reticulin. We conclude that the tTG EIA compares well to both KS and PE IFAs when detecting IgA antibody against endomysium. We do not recommend the use of PE to detect EMA primarily because of the inconsistencies (i.e., tissue selection, quality, and preparation) and limited availability of commercially prepared PE tissue.

Animals↗
PubMed2001

Discussing end-of-life issues with patients: reflections on developing an interviewing template to assist first-year medical students.

First-year medical students at the University of Ottawa currently use an interview template to work with patients who have chronic illnesses. A second-year medical student (JJ) modified the template to facilitate the discussion of death and end-of-life care by students who may have had little previous experience with such sensitive topics. The modification was accomplished using the following strategies: a systematic literature review on long-term care or nursing home residents' end-of-life needs; participation in a support group for families of dying patients; volunteering in a day hospice program for two months; piloting the template with two palliative care patients, one resident of a long-term care facility, and one family member. The paper summarizes and reflects on the process.

Aged↗
PubMed2000

How useful is docusate in patients at risk for constipation? A systematic review of the evidence in the chronically ill.

The effectiveness of docusate for constipation has not been studied in the terminally ill. Controversy also exists concerning its effectiveness in the chronically ill. Because chronically ill patients and terminally ill patients have several risk factors for constipation in common, we undertook a systematic review of prospective controlled trials of oral docusate in the chronically ill to clarify the utility of this drug in populations with advanced disease. The data sources were Medline 1966-April 1997, CINAHL 1982-April 1997, Current Contents August 1996-April 1997, Cochrane Library, a hand search of Index Medicus 1940-1966, three palliative care journals, references in relevant articles and texts, and direct contact with experts. Prospective controlled trials evaluating oral docusate in humans with chronic illness and identifiable risk factors for, or preexisting, constipation were selected. Only materials abstracted in English or French were considered. Information was collected by two independent reviewers and included patient demographic data, study design, dose of docusate, outcomes of stool consistency, stool frequency, need for other laxatives, and assessment of methodologic and reporting quality. Of nine identified studies, four were eligible. These incorporated three different designs and sample sizes that ranged from 15 to 74. Quality assessment scores were low (range 0.46-0.52 with a perfect score being 1.0). Three studies were flawed in blinding of treatment allocation and the use of co-interventions. All studies showed a small trend toward increased stool frequency on docusate. Because of significant clinical heterogeneity in the identified studies, pooled data analysis was not feasible. At present, the use of docusate for constipation in palliative care is based on inadequate experimental evidence. Randomized controlled trials with chronically ill patients and patients with advanced disease are needed to determine its role in prevention and treatment of constipation.

Adolescent↗
PubMed1996

Screening for antinuclear antibodies by enzyme immunoassay.

Indirect fluorescent antibody (IFA) ia most widely used method in clin clinical laboratories to screen for autoantibodies against a wide variety of nuclear antigens. Recently, a number of antinuclear antibody (ANA) enzyme immunoassay (EIA) screens have become commercially available and claim to be an alternative method to screen for ANAs. Given the subjectivity of technical interpretation of IFA and the high number of ANA negative samples, a suitable EIA method for ANA screening would be beneficial to clinical laboratories with large samples volumes. Five ANA EIA screens were compared (Elias, Helix, Sanofi, TheraTest and Zeus) to IFA using a human epithelial cell line (HEp-2). Sera from 601 patients submitted to our reference laboratory for autoimmune testing, and from 202 normal healthy blood donors, were included in this study. Samples with discordant results between IFA and EIA were further analyzed using single antigen EIAs for SSA, SSB, Sm, RNP, Scl-70, histones, dsDNA, and ssDNA. Analyses were based on clinically significant IFA titers of > or equal to 1:160 as positive and <1:40 as negative. When compared to IFA, agreement, sensitivity and specificity for each ANA EIA screen were as follows: Elias: 87.0%, 69.5% and 97.9%; Helix: 94.6%, 90.2%, and 97.3%; Sanofi: 95.0%, 93.7%, and 95.9%; TheraTest: 95.3%, 97.7%, and 93.5%; Zeus: 87.1%, 96.2%, and 81.4%, respectively. In conclusion, screening for ANAs by EIA using several commercial assays was both sensitive and specific when compared to IFA. Moreover, the EIA is objective and much less labor intensive when screening a large number of clinical specimens. None of the EIAs were 100% sensitive and, thus, may fail to detect a few of the nonspecific ANAs that demonstrate atypical as well as classical IFA patterns. The advantages of employing these nonsubjective assays to screen out the vast majority of ANA negative sera is clear. The authors still recommend confirming titers and patterns of sera with positive EIA screens using classical IFA methods employing HEp-2 cells.

Antibodies, Antinuclear↗
PubMed1995

Comparison of three commercially available enzyme immunoassays for the screening of autoantibodies to extractable nuclear antigens.

The initial screening test used in the diagnosis of connective tissue diseases is based on the detection of antinuclear antibodies (ANA) by indirect immunofluorescence (IFA). When the ANA screen is positive, it is often useful to determine the specificity of the autoantibody to a series of extractable nuclear antigens (ENA), a procedure that has been classically performed by double immunodiffusion. Testing large numbers of clinical specimens for autoantibodies to ENA by double diffusion techniques can be time-consuming and expensive. ENA screening systems that employ enzyme immunoassay (EIA) technology have recently become commercially available. We compared three EIA ENA assays to classic Ouchterlony double diffusion techniques. Furthermore, the sensitivity of each antigen and methodology (including ANA immunofluorescence using HEp-2 cells) was tested using ENA positive sera possessing single autoantibodies. Two of the three EIAs that detected immunoglobulin G type autoantibodies to Smith (Sm), ribonucleoprotein (RNP), Sjögren's syndrome-associated antigens Ro (SSA) and La (SSB), were provided by INOVA and Sigma Diagnostics. A third EIA, which also included scleroderma-associated antigen 70 (SCL-70/DNA-topoisomerase I) and histidyl-tRNA synthetase (Jo-1) in addition to the four previously stated antigens, was provided by Clark Laboratories. This latter ENA screen detected IgG, IgA, and IgM type autoantibodies. Included in the study were sera covering a wide variety of anti-nuclear and other autoantibodies. Sensitivity was 100% for all EIA ENA screens when compared to Ouchterlony double diffusion and specificity exceeded 95% in each case. Sensitivity studies showed Ouchterlony to be less sensitive than EIA when detecting low levels of autoantibodies to ENA.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

Comparison of three commercially available assays for detection of varicella-zoster virus antibody.

Three commercially available diagnostic assays for the detection of antibodies to varicella-zoster virus were evaluated to determine which would be the most suitable for our clinical laboratory. Three different methods were examined: an enzyme-linked immunosorbent assay (ELISA), latex agglutination (LA), and an indirect fluorescent-antibody technique. For the 141 serum specimens tested, the ELISA had an agreement of 90.1% and LA had an agreement of 92.2% with the indirect immunofluorescent-antibody technique. The ELISA had a lower sensitivity (85.6%) than LA (100.0%), but suffered from a low specificity (78.4%) compared with the ELISA (98.0%).

Aged↗
PubMedDate not supplied

The many faces of pain for older, dying adults.

An integration of knowledge from the fields of geriatrics, pain management, and palliative care is needed to ensure adequate pain control for the older adult who is dying. An overview is provided of the multiple factors (i.e., chronic illness, malignant disease, care procedures, emotional and cognitive status, response of others) that can cause and exacerbate pain at the end of life for the elderly. Treatment considerations are discussed and an illustrative case study is presented.

Aged↗