Elisa Piva

Erythrocyte Sedimentation Rate Use of Fresh Blood for Quality Control

The erythrocyte sedimentation rate (ESR) remains the most widely used laboratory test for monitoring the course of infections, inflammatory diseases, and some types of cancer. Several test methods have been developed recently, and as a result the safety and reliability of ESR testing procedures have improved. The method recommended by the International Council for Standardization in Haematology and the National Committee for Clinical Laboratory Standards for ESR measurement is based on the traditional Westergren method, using EDTA-anticoagulated samples without dilution. In clinical laboratories, reliable methods for calibration and the use of appropriate control materials are requiredfor monitoring the accuracy and precision of the routine method. We describe and evaluate a procedure for achieving the daily quality control of ESR and for establishing the limits of agreement between working and reference methods. Data from routine patient samples were used to calculate the daily cumulative mean and to monitor its reproducibility over time. Finally, to monitor analytic performance, a comparison was made between results from the measurement of ESR in specimens stored at 4 degrees C for 24 hours and results obtained in fresh samples.

Evaluation of Effectiveness of a Computerized Notification System for Reporting Critical Values

Failure to adequately communicate a critical laboratory value is a potential cause of adverse events. Accreditation requirements specify that clinical laboratories must undertake assessments and appropriate measures to improve the timeliness of critical value reporting and prompt receipt by the responsible caregiver. Documentation and communication processes must be regularly monitored and implemented under ongoing systems for quality monitoring. Critical value reporting is an important phase of the clinical laboratory testing process, and notifications of results outside the target time can indicate ineffectiveness of the process. In the present study, we report data obtained in a 12-month period of critical values analysis and describe a computerized communication system conducive to improving the quality of critical value reporting at a university hospital. Automated communication improves the timeliness of notification and avoids the potential errors for which accreditation programs require read-back of the result. The communication also improves the likelihood of reaching the physician on call and may provide important decision support.

Automated reticulocyte counting: state of the art and clinical applications in the evaluation of erythropoiesis

Abstract The reticulocyte count reflects the erythropoietic activity of the bone marrow and is thus useful in both the diagnosis of anemias and in monitoring bone marrow response to therapy. Starting in the mid-1990s, automated flow-cytometric analysis has replaced traditional microscopic quantitation of reticulocytes. Reticulocyte analysis now includes measurements mRNA content and the maturity of reticulocytes, cell volume, hemoglobin concentration and content. The immature reticulocyte fraction is a reliable early predictor of hematopoietic engraftment following allogeneic stem cell transplantation, while the reticulocyte hemoglobin content provides an indirect measure of the functional iron available for new red blood cell production over the previous 3–4 days. Especially in anemic newborns, reticulocyte analysis is useful to help clinicians follow erythropoietic changes, to monitor response to recombinant human erythropoietin therapy, to gauge transfusion needs, and to evaluate jaundice. Despite improved accuracy and precision, significant problems still persist in maintaining adequate levels of precision and comparability across different laboratories. In the absence of better laboratory standardization, having a single reference range for the parameters provided by flow-cytometric studies of reticulocytes remains problematic. Clin Chem Lab Med 2010;48:1369–80.

Length of sedimentation reaction in undiluted blood (erythrocyte sedimentation rate): variations with sex and age and reference limits.

Abstract Although the length of sedimentation reaction in blood (LSRB) (commonly, but improperly called erythrocyte sedimentation rate, ESR) has long been used in clinical laboratories because it is simple and low-cost, its sensitivity and specificity are unsatisfactory. Usually, the values are reported using the Westergren method with sodium citrate-anticoagulated specimens. We used a new procedure, the Test1™, which measures the length of sedimentation reaction in undiluted K3EDTA anticoagulated blood samples following ICSH (International Committee for Standardization in Haematology) recommendations. Samples obtained from 840 reference individuals (430 females and 410 males, mean age 44 and 46.5 years respectively, range 1 to 90 years) were utilised to estimate the reference limits. The subjects, classified by sex, were subdivided into four statistically different age groups to determine the reference limits (2.5th and 97.5th percentiles). Sex difference was statistically significant in two age groups, from 14 to 50 (p<0.0001) and from 50 to 70 years (p<0.01). We did not observe significant sex difference within the age bracket from 1 to 14 years and from 70 to 90 years. In both sexes LSRB values increased with age, in significant correlation with fibrinogen concentration (p<0.0001), and became significantly higher in subjects older than 70 compared to all the younger subjects (p<0.01 in females and p<0.02 in males). Thus, we defined adequate reference ranges in elderly.

Interpretative reports and critical values

In the clinical laboratory to allow an effective testing process, post-analytical activity can have two goals in trying to improve patient safety: result interpretation and communication of critical values. Both are important issues, and their success requires a cooperative effort. Misinterpretation of laboratory test results or ineffectiveness in their notification can lead to diagnostic errors or errors in identifying patient critical conditions. With the awareness that the incorrect interpretation of tests and the breakdown in the communication of critical values are preventable errors, laboratorians should make every effort to prevent the types of errors that potentially harm patients. In order to improve the reliability of laboratories, we attempt to explain how interpretative reporting and automated notification of critical values can be used to reduce errors. Clinical laboratories can therefore work to improve clinical effectiveness, without forgetting that everything should be designed to provide the best outcomes for patients.

Assessment of critical values policies in Italian institutions: comparison with the US situation

Abstract Background: Critical value reporting is considered an essential tool to ensure the quality of medical laboratory services. Important issues include defining cut-off values, assessing responsibility for communication and adopting information technology solutions to improve notification. Here, we report the state of critical value reporting in a large cohort of Italian laboratories and comparison with Q-Probes surveys from the College of American Pathologists as representatives of the US situation. Methods: To compare critical value policies and procedures, formulation of critical values list with critical values limits and monitoring tools, a web-based questionnaire was formulated for 389 institutions participating in the External Quality Assessment Schemes of Veneto Region, in Italy. Results: A total of 90 clinical laboratories submitted data. Accredited laboratories represented 82.2% of participants, but written procedures for reporting were indicated by 70.5% of participants. Relevant differences between US and Italian policies have been observed, particularly regarding who provides the notification and on the formulation of the cut-off threshold for critical values. Conclusions: Accreditation according to international standards can decrease differences regarding the management of critical values across laboratories of different countries. However, the issues concerning critical limits should be debated and a consensus critical values list should be considered. Automated systems could offer improvements regarding some issues, such as who makes the notification, reducing the time spent in notification of critical values. Surveys for comparing and improving existing policies regarding critical values should be promoted at an international level. Clin Chem Lab Med 2010;48:461–8.

Respiratory Burst of Neutrophils in Diabetic Patients with Periodontal Disease

Periodontal disease, a frequent complication of diabetes mellitus, is the major cause of tooth loss. However, studies on neutrophil function in patients with this condition have yielded contradictory findings. The NADPH oxidase activity of 40 diabetic patients with periodontosis who were on metabolic control was evaluated and compared with that in 40 healthy subjects. Superoxide anion production was measured by a photometric method, with NBT reduction at 490 nm in a microplate reader and by a microscopic method, with a percentage of positive PMNs with granules of formazan in the cytoplasm. When the PMN respiratory burst was activated by phorbol myristate acetate (PMA), a protein kinase C (PKC) soluble activator, superoxide production of diabetics (4.31 +/- 1.67 A x 10(-3)/min) and normal subjects (4.25 +/- 1.25 A x 10(-3)/min) was comparable by photometric method, whereas a significantly defective response to opsonized zymosan was observed when the microscopic method was used (58 +/- 17% in diabetics and 66 +/- 18% in controls; p = 0.05). Therefore in patients with diabetes the impact on PMN function is of multifactorial origin, and is probably correlated to the glucose level and to glycation of PMN protein, such as NADPH oxidase or myeloperoxidase. Alternatively, glucose in PMN may be reduced by aldose reductase to polyols, and this pathway requires NADPH, the coenzyme for the respiratory burst. Moreover, we found that superoxide production in response to opsonized zymosan was reduced in diabetic patients. The activation of protein tyrosine kinase (PTK) is an important mechanism underlying transmembrane signaling and, moreover, protein tyrosine phosphorylations, stimulated by zymosan receptor-mediated activation, might be caused by the activation of specific PTK, whereas activation by PMA is probably mediated through another PKC type.

An immunological evaluation of type II diabetic patients with periodontal disease.

Peridontal disease is a frequent complication of diabetes, and diabetic subjects often exhibit decreased immune response with increased susceptibility to infection. We evaluated the possible relationship between immune response and periodontal disease in 40 type II diabetic patients, mean (+/- SD) age 59 +/- 8 years and mean disease duration 17 +/- 4 years, with good metabolic control (mean fasting plasma glucose, 10.5 +/- 3.8 mM/L, mean HbA1c 8.1 +/- 1.66%), and in 40 age and gender-matched controls. Interproximal alveolar bone loss (ABL), as the percentage of bone loss from the cement enamel junction (CEJ) to the apex, was measured with a modified Schei ruler at the deepest point on the mesial/distal surface of the teeth, except third molars, on a panoramic radiograph. Immunological evaluation involved study of NADPH neutrophil superoxide production, neutrophil chemotaxis, lymphocyte subpopulations, immunoglobulins and complement. Diabetic patients showed significant differences compared with controls regarding ABL (30.6 +/- 14.7% versus 17.6 +/- 4.3%; p < 0.0001) and the T-helper/T-suppressor ratio (2.3 +/- 1.0% versus 1.8 +/- 0.8%; p < 0.05). Other parameters of cell-mediated immunity and humoral immune response did not show any significant variations. No correlation between immunological and radiographic analysis parameters were found. Further studies are needed to verify the exact role played by immunological factors in type II diabetic patients with periodontal disease.

Clinical Utility of Reticulocyte Parameters

The reticulocyte count reflects the erythropoietic activity of bone marrow and is thus useful in both diagnosing anemias and monitoring bone marrow response to therapy. Automated flow-cytometric analysis has led to a significant advance in reticulocyte counting, by simultaneously providing additional parameters and indices such as the reticulocyte immature reticulocyte fraction (IRF), the reticulocyte volume, and the hemoglobin content and concentration. IRF has been proposed as an early marker of engraftment. Reticulocyte hemoglobin content is useful in assessing the functional iron available for erythropoiesis, and reticulocyte volume is a useful indicator when monitoring the therapeutic response of anemias.

Laboratory critical values: automated notification supports effective clinical decision making.

OBJECTIVE Failure to adequately communicate a laboratory critical value (CV) is a potential cause of adverse events. The harmonization of CV reporting is increasingly recognized as a key issue in ensuring patient care and minimizing harm. With ongoing improvements in CV reporting, the patients outcome should be audited to assess the effectiveness of CV notification. DESIGN AND METHODS We report the data audited throughout a six month-period during which an analysis was made of CVs, and we describe the approach of clinicians and general practitioners (GPs), and their decision making following CV reporting. RESULTS CV notification led to a change of treatment in 98.0% of patients admitted to surgical and in 90.6% of those admitted to medical wards. Clinicians made a further evaluation of new complications in patients in 70.0% and 60.4% of cases, in surgical and medical wards respectively. In more than 40.0% of cases, CVs were unexpected findings. In the primary care setting, critical hyperkalemia was managed by GPs in 55% of patients, thus sparing patients hospitalization. For all outpatients with critical INR (international normalized ratio), the GPs changed or stopped warfarin dosage. Twenty-four percent of patients were checked for an additional INR, whereas a further medical examination by a consultant in the hospital setting was requested for 5% of patients. CONCLUSIONS The laboratory plays a key role in ensuring patient safety, especially in CV reporting. An evaluation should be made of the patients outcome and clinical decision making in order to assess the effectiveness of the CV process.