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P J Howanitz

Publications and source records attributed to P J Howanitz.

At least 19 recordsLinked to original sources
PubMed1992

Prevalence of non-A,non-B hepatitis/hepatitis C virus antibody in human immunoglobulins.

Human intravenous immunoglobulins prepared by the cold ethanol fractionation technique of Cohn are considered safe with respect to infectivity. However, there have been several instances of transmission of both hepatitis B and non-A,non-B hepatitis viruses after administration of intravenous immunoglobulins. To determine the prevalence of hepatitis C virus antibody in intravenous immunoglobulins and protein preparations, 30 commercially available products were tested. Using the Abbott enzyme immunoassay for hepatitis C virus antibody, 27 of 30 (90%) immunoglobulins tested positive. The Ortho immunoassay showed that 28 of 30 (93%) were positive, with one discordant result between the Ortho and Abbott assays. An antigen-blocking or neutralization test (Abbott) confirmed the results of the Ortho assay. Bovine, sheep, goat, and horse sera also were tested before and after isolation of animal immunoglobulins. All results on the animal sera were negative, indicating that the fractionation process did not produce false-positive results. The high prevalence rate of hepatitis C virus antibody in intravenous immunoglobulins has important implications for follow-up of recipients, selection of serum donors, and implementation of anti-hepatitis C virus testing.

Hepatitis Antibodies↗
PubMed1992

A nationwide quality assurance program can describe standards for the practice of pathology and laboratory medicine.

An important component of quality assessment is the analysis of peer group comparisons, although little data are available for evaluation. We developed and tested six interinstitutional quality indicators related to Pathology and Laboratory Medicine among 36 institutions. Results showed that the mean frequency of intraoperative frozen section consultations (6.0%), sensitivity of fine needle aspiration cytology diagnosis (87%), nosocomial infections (5.0%) and average cross-match to transfusion ratio (2.1%) was comparable with previous studies, but the range of values was large. The median stat laboratory turnaround time of approximately 1 hr for CSF cell count, glucose, protein and gram smear was considerably longer than expected from previous investigations, and was longer for larger institutions. Analysis of serious laboratory reporting errors showed the lowest number detected by individuals working in transfusion medicine, and highest numbers among hematology workers. We conclude that interinstitutional comparison of data from quality assurance programs can be used to describe performance standards related to the quality and effectiveness of care.

Biopsy, Needle↗
PubMed1992

Quantification of errors in laboratory reports. A quality improvement study of the College of American Pathologists' Q-Probes program.

Over a 3-month period, 61,496 errors were detected in clinical laboratory reports by 631 participants in the College of American Pathologists' 1990 Q-Probes program. Each error detected was defined as an opportunity for improvement. Almost 4% of the detected errors were attributed to nonlaboratory personnel and approximately 4% (A errors) had a major impact on patient care. Rates of B (serious errors, but unlikely to affect patient care) and C errors (minor clerical errors) were approximately equal. When expressed in terms of measures of laboratory work loads, four of six measures of mean errors were lowest in blood banking, intermediate in chemistry and microbiology, and highest in hematology. Thirteen percent of participants did not have an error detection system in place. We conclude that many errors go undetected, and we recommend that an effective system for error detection in patient reports should be employed in all laboratories.

Blood Banks↗
PubMed1992

Preoperative autologous blood donation in 612 hospitals. A College of American Pathologists' Q-Probes study of quality issues in transfusion practice.

We compared predeposit autologous blood utilization practices in 612 hospitals (where 107,559 autologous and 2,504,522 homologous units were transfused in all of 1989). Participating blood bankers prospectively followed up donors who presented for initial donation during an 11-week period in early 1990. They recorded the number of autologous donors whose blood was drawn (n = 22,276); units that were donated (n = 40,163), transfused (n = 23,988), crossed over (n = 937), and discarded (n = 15,443); and donors transfused with autologous blood only (n = 11,923) or donors who received homologous blood (n = 2002). Most donors (89.7%) avoided homologous blood, including donors (39.5%) who did not require transfusion. Units that were donated for low-risk surgery represented 23.1% of all units that were collected, and the rate of donation for these procedures was directly proportional to the percentage of donors who did not require transfusion and to the discard rate. We concluded that a major focus of quality improvement in autologous transfusion practice should be the reduction of donations for surgical procedures for which blood replacement is rarely needed.

Blood Donors↗
PubMed1992

Emergency department stat test turnaround times. A College of American Pathologists' Q-Probes study for potassium and hemoglobin.

We report aggregate turnaround times (TATs) from phlebotomy to result reporting of emergency department patients' hemoglobin and potassium results for 722 subscribers to the College of American Pathologists Q-Probes program. Approximately 40,000 specimens were obtained for each analyte. Median interinstitutional TAT time of 25 minutes for hemoglobin and 36 minutes for potassium varied little by shift, weekdays, or weekends. The type of personnel collecting the specimen and the method of specimen transport were the most important factors affecting TATs. Specimen transit times accounted for approximately one third of the total TATs, but when couriers transported hemoglobin specimens, the median transit time was equivalent to the median intralaboratory test TAT. The influence of various measures used to improve test transit and TATs is presented.

Bloodletting↗
PubMed1991

Using Q-Probes to improve the quality of laboratory medicine: a quality improvement program of the College of American Pathologists.

This paper will review the reasons for the increasing emphasis on quality assurance in American healthcare and laboratory medicine. This emphasis is driven in part by economic, social and regulatory concerns as well as the traditional commitment to the search for excellence in services provided to patients. The Q-Probes Program of the College of American Pathologists (CAP) represents a response to these pressures and will be described in some detail. The program is based upon the historical success of interlaboratory comparison programs developed and sponsored by the CAP in achieving demonstrable improvement in laboratory performance. These programs are dependent on the gathering of data from large numbers of laboratories in order to establish provisional "benchmarks" of quality practice which serve as a baseline for systematic quality improvement efforts. The Q-Probes Program gathers peer-group specific institutional data concerning defined aspects of quality practice in pathology and laboratory medicine. These highly structured programs provide laboratories and pathology services with a format to collect data for submission to the CAP for analysis and to compare their performance against that of appropriately stratified peer groups. Several representative examples chosen from clinical laboratory medicine and pathology will be presented. We will attempt to demonstrate how individual laboratory and pathology services utilize aggregate data to effect specific changes in practice that lead to improvement in processes of patient care and better patient outcomes.

Blood Specimen Collection↗
PubMed1991

Assessment of biological reagents for presence of human immunodeficiency virus-1 (HIV-1) antigens.

We tested 122 biological reagents including laboratory quality assurance sera and therapeutic human immune serum globulin products using an immunoenzymometric assay (IEMA) for HIV-1 antigens. Biological reagents tested were 64 HIV-1 antibody non-reactive and 44 HIV-1 antibody reactive quality assurance samples, and 14 HIV-1 antibody reactive human immune serum globulins from 21 manufacturers. Twenty-one of these biological reagents were previously reported by us as Western blot reactive. All 122 samples tested were non-reactive for HIV-1 antigens. Low incidence of HIV-1 antigen in these biological reagents should not alter laboratory safety practices in which all samples are considered infectious. Use of HIV-1 antigen measurements, either alone or with HIV-1 antibody determinations does not increase the likelihood of detecting HIV-1 reactive samples.

AIDS Serodiagnosis↗
PubMed1991

Prevalence of non-A, non-B hepatitis/hepatitis C virus antibody in laboratory quality-assurance sera.

Quality-assurance sera (QAS) are prepared from pooled sera composed of thousands of individual donations. Previous studies documented that a substantial percentage of individual QAS test positive for viral disease markers, including antibodies to human immunodeficiency virus and to hepatitis B surface antigen. We tested 239 QAS from various proficiency programs and commercial sources to determine the prevalence of hepatitis C virus (HCV) antibody. We tested samples for anti-HCV by using an enzyme immunoassay (EIA; Abbott Labs.) and an enzyme-linked immunosorbent assay (ELISA; Ortho Diagnostics). We observed an overall positive rate of 49% by one or both assays in all categories of sera tested. In addition, we found a greater rate of positivity (58%) in proficiency program samples than in commercial samples (43%). We found discrepant results between the two assays for 15 of 239 samples (6%). In the discrepant samples, the EIA result was positive, whereas the ELISA result was negative. Anti-HCV positivity in QAS has important implications for laboratory personnel handling these samples.

Antibodies, Viral↗
PubMed1991

Interinstitutional comparison of frozen-section consultation. A College of American Pathologists Q-Probe study of 79,647 consultations in 297 North American institutions.

In 1989, the College of American Pathologists Q-Probes Quality Assurance Program studied intraoperative frozen-section consultations performed in 297 institutions with mean bed size of 316 (range, 0 to 1351 beds) in North America during 5 consecutive months. The aggregate database was composed of 933,751 surgical cases (mean, 3144 per institution); 52,464 frozen-section cases (mean, 177); and 79,647 individual frozen sections performed (mean, 268). The rate of frozen sections per all surgical case accessions was 5.6% (cases with frozen section) and 7.3% (individual frozen sections performed), with an average of 1.5 frozen sections per case. Frozen-section rate increased proportional to bed size, from less than 5% in institutions with bed size below 150 to 15% in institutions with bed size above 600. Of all frozen sections performed, 4.2% were deferred. Deferrals to paraffin sections in pathologists' opinions were 92.6% appropriate, 1.2% inappropriate, and 6.2% not stated. When frozen-section diagnoses were compared with permanent section diagnoses, there was a 98.3% diagnostic concordance, adjusted for deferred diagnoses, but including the performance of frozen sections on mammographically directed biopsy specimens with no gross abnormalities in 80% of institutions. This practice accounted for 11.8% of the discordant frozen-section diagnoses. The reasons for diagnostic discordances were gross tissue sampling (44.8%); misinterpretation (40%); sectioning (12.7%); inadequate history (5.6%); staining (1.5%); labeling (0.5%); and other (3%). Assessment of diagnostic discordance on patient outcomes by the reviewing pathologist showed that patient management was unaffected in 74%, minimally affected in 20%, and greatly affected in 2.5%.

Biopsy↗
PubMed1991

Interinstitutional comparison of performance in breast fine-needle aspiration cytology. A Q-probe quality indicator study.

In 1989, the College of American Pathologists, Northfield, Ill, instituted a voluntary quality assurance program, called "Q-Probes," that utilized nationwide interinstitutional peer comparison. One of the anatomic pathology modules retrospectively assessed performance in fine-needle aspiration cytology (FNAC) of the breast from cytohistologic correlations that were made in 294 institutions by 988 pathologists on their own cases that were accessioned during a 6-month period. Of the 13,066 cases of FNAC, 10,751 (82%) were satisfactory for evaluation. Of these satisfactory aspirates, 3471 cases (33%) had histologic correlation, which formed the basis for determining diagnostic accuracy. Of breast aspirates, 2254 (17%) were unsatisfactory for evaluation, with the mean frequency of unsatisfactory aspirates obtained by nonpathologists (18%), ie, more than twice that of unsatisfactory aspirates obtained by pathologists (7.2%). In the diagnosis of breast cancer by FNAC, the following performance results were derived with the use of the aggregate data: 82% sensitivity of the FNAC procedure, 97% sensitivity of diagnosis, 97% specificity, 95% positive predictive value, 86% negative predictive value, and 90% efficiency. No significant difference in performance was detected when institutions were stratified by six peer group characteristics. We made the following conclusions: (1) the aggregate and median breast FNAC performance values obtained from this interinstitutional comparison of data from routine procedures performed in diverse settings in North America compared very favorably with performance from single institutions published in studies of similar design in the literature, and (2) these data may provide a reference point for participant institutions to measure future quality improvement in fine-needle aspiration of breast.

Biopsy, Needle↗
PubMed1991

Intralaboratory performance and laboratorians' expectations for stat turnaround times. A College of American Pathologists Q-Probes study of four cerebrospinal fluid determinations.

More than 400 laboratories participated in the module of the College of American Pathologists' quality assurance program, Q-Probes, which measured intralaboratory turnaround time (TAT) of stat cerebrospinal fluid tests. Four determinations encompassing more than 14,000 specimens were monitored and intralaboratory TATs were compared with participants' TAT goals. The median TATs were as follows: cell count, 32 minutes; glucose, 34 minutes; protein, 37 minutes; and Gram's stain, 45 minutes. Between 14% and 21% of participants (test dependent) met their goals 100% of the time, with 72% of the determinations completed within the time laboratorians required. Standard statistical stepwise regression analysis was used to model influence of up to eight factors on TAT. Correlations were test and bed-size dependent, but ranged from a high of .23 to a low of .02. Only computerized reporting and instrumentation measuring protein and glucose had a consistent effect, delaying TAT, whereas use of a stat laboratory, one workstation, automation, computerized order entry, and centralized processing gave variable results. We conclude that laboratorian goals for cerebrospinal fluid test TAT are met most of the time, and that a stepwise regression analysis poorly explains factors that statistically influence TAT.

Cerebrospinal Fluid↗
PubMed1991

Laboratory phlebotomy. College of American Pathologists Q-Probe study of patient satisfaction and complications in 23,783 patients.

Outpatients from 630 institutions participated in a phlebotomy module of Q-Probes, a quality assurance program of the College of American Pathologists, Northfield, Ill. This module assessed patient outcome measurements of complications, discomfort, and satisfaction with the phlebotomy procedure. Of the 29,700 ostensibly healthy individuals registered, 80.1% returned postcards containing measurements and assessments they made about the procedure and information recorded by the phlebotomist. The median time required for phlebotomy was 6 minutes, with 25% of patients requiring less than 5 minutes and 10% more than 21 minutes for completion of the procedure. The average number of phlebotomy attempts per patient was 1.03, with 95 patients (0.4%) experiencing three to 11 attempts. Ecchymoses occurred in 4048 (16.6%) attempts, with the median size of ecchymosis being 15.1 mm. On the average, an outstanding employee was identified by patients 46.6% of the time. The discomfort caused by the needle puncture was more than expected by 35.3% of patients. Although 98.6% of the patients were satisfied, 336 patients were dissatisfied with the procedure. We conclude that the technical skills of phlebotomists and patient satisfaction with phlebotomy are outstanding, but that patient discomfort from the procedure needs to be minimized.

Bloodletting↗
PubMed1990

Quality assurance measurements in departments of pathology and laboratory medicine.

Previously, characteristics of the quality assurance program in each department of pathology and laboratory medicine were the uniqueness of the monitors selected, the thresholds set for activity, and definitions of good performance. In 1989, members of the College of American Pathologists developed and implemented the first nationwide quality assurance program for pathology and laboratory medicine. This program, Q-Probes, has been expanded for 1990; after completion of planning under way for 1991, indicators will be in place for all steps in the total testing process. More than 1100 institutions had subscribed by the first quarter of 1990. Input forms for measurements of clinical indicators of quality are distributed to participants and, after completion, submitted to a central computer facility where keypunching and data manipulations occur. The interpretation of results is enhanced by peer comparisons of the participant data collected. In many circumstances studied, a large proportion of the data are aggregated at extreme ends of the distribution. Because data distributions are nongaussian for the indicators studied, it is recommended that peer comparisons use the 10% to 90% range and that the central tendency be described as the median. Despite large databases for some indicators that exceed by more than 10- to 100-fold those previously reported, extensive categorization may preclude percentile ranking of participants. Critiques are distributed describing practices and suggestions for improvement. Steady improvement of each participant and of nationwide practice patterns are documented by remeasurements.

Data Collection↗
PubMed1990

The accuracy of frozen-section diagnoses in 34 hospitals.

We compared the diagnoses from intraoperative frozen-section consultation with the final diagnosis using permanent tissue sections from 34 hospitals throughout North America. Participating pathologists who provided data from their practices volunteered for a pilot study of Q-Probes, a modular quality assurance program of the College of American Pathologists, Skokie, III. During 4 weeks, 186 pathologists evaluated 1952 frozen-section cases and deferred diagnoses to the final permanent sections in 77 cases (3.9%). Concordance between frozen-section and the final histologic diagnoses was 96.5%; whereas the mean and median concordance rates for participating institutions were 96.8% and 97.4%, respectively. Of 67 discordant diagnoses, 29 occurred from sampling of nonrepresentative tissue specimens, and 29 from diagnostic misinterpretations. The pathologists indicated that the diagnostic discordance had little or no effect on patient care in 94% of cases. We conclude that the North American pathologists studied interpret frozen sections with exceedingly high accuracy, approximating that reported from teaching hospitals.

Frozen Sections↗
PubMed1988

Use of proficiency test performance to determine clinical laboratory director qualifications.

Many activities and policies influence laboratory test quality. Proficiency test results are one measure of laboratory quality, and during the past 25 years, five studies have examined the relationship of laboratory director educational requirements to proficiency test results. Data from three studies support the association between director qualifications and quality as measured by proficiency test performance, whereas no relationship was found in the other two studies. Possible reasons for conflicting results include differences in database size and demographics; in addition, proficiency test results may be inappropriate, although widely used, as the sole measure of laboratory director performance.

Administrative Personnel↗
PubMed1988

Immunoassay. Development and directions in antibody technology.

Improvements and new applications for the technique of immunoassay have been extensive, owing in part to improvements in specific binding reagents used. Early reports advocated application of naturally occurring antibodies, specific serum-binding proteins, and receptors as binding reagents in immunoassays. Each is still used today, although applications are limited because affinities are generally low. Polyclonal antibodies produced in laboratory animals in response to injection of specific antigens have been the cornerstone of immunoassay because of their high affinities and wide range of specificities. Recently, monoclonal antibodies have begun to replace polyclonal antibodies because of improved specificity, ease of use, production of an unlimited supply, and advantages of worldwide assay standardization. Although only 50 analytes are currently measured by Food and Drug Administration--approved reagents, widespread use in the future is predicted.

Antibodies, Monoclonal↗
PubMed1987

Influence of specimen treatment on nonreactive HTLV-III sera.

We investigated effects of specimen treatment on HTLV-III antibody assay results. Freezing and thawing specimens 10 times did not increase specimen mean absorbance (A) values measured by the Abbott immunoenzymometric assay (IEMA). Heating blood donor serum specimens at 56 degrees C for at least 10 min inactivates virus, but converted 7.1% of nonreactive specimens to positive when measured by this IEMA. Also heating at 56 degrees C for 30 min increased A values of most specimens; however, the conversion to positive within assay ranged from 0 to 75%, with a mean of 17%. When 56 nonreactive patient specimens were heated, 55% became Abbott IEMA reactive, although ENI IEMA values did not increase and Western blot results remained nonreactive. Binding of immunoglobulins G and A to Abbott IEMA beads did not cause this conversion after heat treatment. We postulate that heating specimens causes alteration of some serum matrices and introduces nonspecific binding to assay bead antigen or antibody reagents. We recommend that for the Abbott IEMA, specimens may be stored frozen, and must not be heated to avoid altered reactivity.

Antibodies, Viral↗