Factitious biochemical measurements resulting from hematologic conditions

Erroneous potassium results: preanalytical causes, detection, and corrective actions

Potassium is one of the most requested laboratory tests. Its level is carefully monitored and maintained in a narrow physiological range. Even slightly altered potassium values may severely impact the patient's health, which is why an accurate and reliable result is of such importance. Even if high-quality analytics are available, there are still numerous ways in which potassium measurements may be biased, all of which occur in the preanalytical phase of the total laboratory testing process. As these results do not reflect the patient's in-vivo status, such results are referred to as pseudo-hyper/hypokalemia or indeed pseudo-normokalemia, depending on the true potassium result. Our goal in this review is to present an in-depth analysis of preanalytical errors that may result in inaccurate potassium results. After reviewing existing evidence on this topic, we classified preanalytical errors impacting potassium results into 4 categories: 1) patient factors like high platelet, leukocytes, or erythrocyte counts; 2) the sample type 3) the blood collection procedure, including inappropriate equipment, patient preparation, sample contamination and others and 4) the tube processing. The latter two include sample transport and storage conditions of whole blood, plasma, or serum as well as sample separation and subsequent preanalytical processes. In particular, we discuss the contribution of hemolysis, as one of the most frequent preanalytical errors, to pseudo-hyperkalemia. We provide a practical flow chart and a tabular overview of all the discussed preanalytical errors including possible underlying mechanisms, indicators for detection, suggestions for corrective actions, and references to the according evidence. We thereby hope that this manuscript will serve as a resource in the prevention and investigation of potentially biased potassium results.

Short-Term Storage of Mobilized Peripheral Blood Stem Cells in a Closed System Changes the Microenvironment and May Affect the Quantity of CD34+ and CD34+CD38-CD45RA-CD90+ Cells

Hypoxic conditions preserve the multipotency and self-renewing capacity of murine bone marrow and human cord blood stem cells. Blood samples stored in sealed blood gas tubes become hypoxic as leukocytes metabolize and consume oxygen. Taken together, these observations suggest that peripheral blood stem cell (PBSC) samples stored under airtight conditions become hypoxic, and that the stem cells contained may undergo qualitative or quantitative changes. This study aimed to determine the effect of storage for 8 hours in a sealed system on PBSC samples. Granulocyte colony-stimulating factor-mobilized PBSC samples were collected prospectively from 9 patients with myeloma or amyloidosis prior to apheresis, followed by measurement of CO2, O2, hydrogen ion (pH), lactate, and glucose concentrations in the blood and immunophenotyping of stem cell and multipotent progenitor cell populations before and after 8 hours of storage in sealed blood collection tubes. Blood concentrations of O2 and glucose and pH measurements were significantly decreased, whereas concentrations of CO2 and lactate were significantly increased after storage. Significantly higher concentrations of CD34+ cells (552 ± 84 cells/106 total nucleated cells [TNCs] versus 985 ± 143 cells/106 TNCs; P = .03), CD34+CD38- cells (98 ± 32 cells/106 TNCs versus 158 ± 52 cells/106 TNCs; P = .03), CD34+CD38+ cells (444 ± 92 cells/106 TNCs versus 789 ± 153 cells/106 TNCs; P = .03), and CD34+CD38-CD45RA-CD90+ cells (55 ± 17 cells/106 TNCs versus 89 ± 25 cells/106 TNCs; P = .02) were detected after 8 hours of storage. The changes in concentrations of CD34+CD38+ cells and CD34+ cells were inversely associated with the change in glucose concentration (P = .003 and P < .001, respectively) and positively associated with the change in lactate concentration (P = .01 and P <.001, respectively) after 8 hours of airtight storage. Storage of PBSC samples in a sealed, airtight environment is associated with microenvironmental changes consistent with hypoxia and increased concentrations of immunophenotypically defined stem cells. These results may have clinical implications with regard to the collection and processing of stem cell products and warrant confirmation with functional and mechanistic studies.

Falsely Elevated Estradiol Results in a 62-Year-Old Male Patient

Falsely increased estradiol levels can lead to unnecessary tests and therapeutic interventions. Here, we present a case of a 62-year-old man with falsely elevated estradiol, which led to subsequent follow-up testing and prescriptions. Alternative immunoassay testing, in conjunction with Scantibodies' blocking reagents, polyethylene glycol precipitation, and liquid chromatography-tandem mass spectrometry confirmation demonstrated that the falsely elevated estradiol was due to the presence of macro-estradiol. This report emphasizes the importance of recognizing analytical interferences in immunoassays to appropriately manage subsequent testing and patient care.

Spurious laboratory results associated with immunoglobulin M gammopathy in a dog with multiple myeloma

An 11 year old female-neutered Labrador presented for facial swelling. Clinicopathological abnormalities included hyperglobulinemia, azotemia, hypercalcemia, nonregenerative anemia, thrombocytopenia, and spurious hypoglycemia. Normoglycemia was subsequently confirmed using a cage-side analyzer (AlphaTRAK, Zoetis, UK). Serum and urine protein electrophoresis documented monoclonal (immunoglobulin M) gammopathy with Bence-Jones proteinuria. Computed tomography imaging revealed a monostotic osteolytic bone-lesion, and bone marrow cytology and histopathology documented plasmacytosis with multiple myeloma oncogene 1 / interferon regulatory factor 4 positivity, consistent with multiple myeloma. Infectious disease testing initially indicated seropositivity for Leishmania, Borrelia, and Anaplasma spp.; however, Leishmania PCR (splenic and bone marrow aspirates), and paired serological titers for Borrelia and Anaplasma were negative. Consequently, initial serological results were considered to be false positive because of paraproteinemia-associated assay interference. Chemotherapy (prednisolone and melphalan combination therapy) was initiated, but the dog was euthanased 30 days later because of the development of pericardial effusion. This is a report of spurious serological (and other laboratory) results occurring secondary to monoclonal gammopathy in a dog.

IgA Monoclonal Gammopathy with Pseudohyperphosphatemia

Monoclonal gammopathies (MGs) reflect conditions in which abnormal amounts of immunoglobulins are produced by a clone that developed from a single pro-B germ cell. They range from asymptomatic, benign disorders such as monoclonal gammopathy of undetermined significance to malignant plasma cell and lymphoid disorders, including multiple myeloma and Waldenstorm macroglobulinemia. The identification of the particular subtype of immunoglobulin molecule is done by serum immunofixation by use of specific antisera directed against different subtypes of immunoglobulin classes. However depending upon the characteristic position taken up by migrating M band on protein electrophoresis due to its molecular weight and charge, serum protein electrophoresis can itself reveal the nature of the immunoglobulin without the need to do serum immunofixation. IgA mostly migrates to beta globulin region and may often be missed out for lack of a sharp, discrete M band in gamma globulin region. Systemic manifestations of MG can be attributed to the physicochemical properties of the monoclonal immunoglobulin, to its antibody activity or to other mechanisms. We describe a case of IgA MG with pseudohyperphosphatemia.

Contribution of the laboratory to a diagnosis process by sequential reflective testing: Paraprotein interference on a direct bilirubin assay

Errors in laboratory medicine occur in the preanalytical, analytical, and postanalytical phases. The errors are mostly detected in the preanalytical period. However, analytical errors are still an important source of error, despite their frequency is reduced significantly in years thanks to developments in laboratories. In this case, an analytical error was noticed during the verification of a patient’s results. The direct bilirubin of a 66-year-old male patient admitted to the emergency department was higher than the total bilirubin. The patient’s symptoms were fatigue and dyspnoea. Albumin and haemoglobin (Hb) concentrations of the patient were significantly low. After considering the patient’s demographics and laboratory results, the laboratory specialist suspected a paraproteinemia interference. Total protein was performed as a reflective test. The albumin/globulin ratio was reversed. Thereafter, serum protein electrophoresis (SPEP) and immunofixation electrophoresis (IFE) were performed as another reflective tests, respectively. SPEP and IFE results were in favour of monoclonal gammopathy. The patient was directed to a haematologist, underwent a bone marrow biopsy, and the result was reported as Waldenstrom’s macroglobulinemia with plasma cell differentiation expressing IgM-Kappa. The patient went on a chemotherapy protocol, and his condition has been improved in subsequent months. Detection of analytical errors is of great importance, like in our case, and may be used as a tool to identify patients who have not yet been diagnosed. The laboratory specialist must dominate the entire process of each test in the laboratory, be aware of the limitations of tests, and turn these disadvantages into advantages when necessary.

Errors within the total laboratory testing process, from test selection to medical decision-making - A review of causes, consequences, surveillance and solutions

Laboratory analyses are crucial for diagnosis, follow-up and treatment decisions. Since mistakes in every step of the total testing process may potentially affect patient safety, a broad knowledge and systematic assessment of laboratory errors is essential for future improvement. In this review, we aim to discuss the types and frequencies of potential errors in the total testing process, quality management options, as well as tentative solutions for improvement. Unlike most currently available reviews on this topic, we also include errors in test-selection, reporting and interpretation/action of test results. We believe that laboratory specialists will need to refocus on many process steps belonging to the extra-analytical phases, intensifying collaborations with clinicians and supporting test selection and interpretation. This would hopefully lead to substantial improvements in these activities, but may also bring more value to the role of laboratory specialists within the health care setting.

Pre-analytical mysteries: A case of severe hypervitaminosis D and mild hypercalcaemia

We describe a case of severe hypervitaminosis D and mild hypercalcaemia in a 68-year-old woman who presented with fatigue and weight loss. Her 25-hydroxy vitamin D (25OHD) was > 400 nmol/L (50-150) and corrected serum calcium was 2.83 mmol/L (2.1-2.6). Her intact parathyroid hormone (PTH) was 4.9 pmol/L (2.0-9.5). Further investigation revealed an IgM kappa paraprotein, and a bone marrow aspirate confirmed a diagnosis of lymphoplasmacytic lymphoma/Waldenstrom’s macroglobulinemia (LPL/WM). As the vitamin D level was discordant with the patient’s other results and presentation, the presence of an assay interferent was suspected. A 1-in-2 dilution of the sample returned a 25OHD result of 84 nmol/L in keeping with the presence of an interferent. Testing for rheumatoid factor was negative. The sample was treated with an antibody blocking reagent (Scantibodies) and results were not consistent with heterophile antibody interference. The sample was then analysed using liquid chromatography tandem mass spectrometry (LC-MS/MS), which returned a 25OHD result of 82 nmol/L. Testing on an alternative immunoassay platform produced a 25OHD result of 75 nmol/L. Reapeted testing on the original platform following reduction of the monoclonal paraprotein with chemotherapy, returned a result of 64 nmol/L. The patient’s mild hypercalcaemia persisted following resolution of the monoclonal paraprotein, in keeping with a diagnosis of primary hyperparathyroidism. This case highlights the potential for paraproteins to cause assay interference, and the importance of considering interference when results are incongruous with the clinical presentation.

Falsely Elevated Thyroid-Stimulating Hormone Results due to Interference by M-Component of IgG-Lambda Type

Heterophilic antibodies but also M-components can interfere with laboratory tests causing erroneous results. We report the case of a 75-year-old man with myeloma and a monoclonal immunoglobulin component (M-component) that caused elevated thyroid-stimulating hormone (TSH) results. The M-component was of the IgG-lambda type. Thyroid markers were analyzed repeatedly, and there was a clear association between IgG concentrations and TSH values (R² = 0.724). The highest TSH value was 75 mIU/L. Polyethylene glycol (PEG) precipitation of intact immunoglobulins was used to investigate if there was an antibody-related interference problem. The PEG treatment normalized the TSH value, showing that the cause of the elevated TSH result was due to interference caused by the M-component. In conclusion, it is important to remember that both heterophilic antibodies and M-components may cause erroneous results.

A case of monoclonal gammopathy of undetermined significance with abnormal low levels of plasma glycated albumin by M protein

BACKGROUND

It is known that an immunoglobulin abnormality affects various clinical laboratory measurements and leads to abnormal values. We experienced a case of monoclonal gammopathy of undetermined significance (MGUS) showing a falsely low plasma glycated albumin (GA) level.

CASE REPORT

The patient was a 75-y-old male who visited our hospital for thrombocytosis identified during a medical checkup. Based on further examinations, he was diagnosed with MGUS (IgM-κ type). Laboratory examinations revealed that the plasma GA level was significantly low at -1.3% but the serum GA level was reasonable at 15.5%. We investigated the cause of the falsely low plasma GA level.

RESULTS

The patient's plasma became turbid after mixing with the first reagent for GA measurement. The plasma GA level was increased by dilution of the plasma. The plasma GA level was falsely decreased only at the time of measurement on a sample collected using a blood-collecting tube with heparin sodium. The GA level was decreased by adding heparin sodium to the patient's serum, whereas the GA level was increased by neutralization of the patient's plasma with protamine sulfate. The GA level was increased after adding polyethylene glycol to the patient's plasma. Serum GA levels in healthy controls were decreased by adding purified M protein from the patient's serum.

CONCLUSIONS

We report a patient with MGUS whose plasma GA concentration was falsely decreased by M protein when blood was drawn in a heparin sodium-containing tube.

Pseudohyperphosphatemia in a patient with incidentally identified progression of smoldering myeloma

BACKGROUND

Pseudohyperphosphatemia is a rare laboratory finding in MM, especially in patients with smoldering myeloma (SMM) progressing to symptomatic multiple myeloma (MM). Laboratorians and clinicians should be aware of this phenomenon and take necessary actions to avoid misdiagnosis.

METHODS

Specimens from a monoclonal IgG kappa SMM patient with extremely high serum phosphorus concentrations measured by the Roche phosphomolybdate assay were re-evaluated using serial dilutions and the ORTHO VITROS assay free from monoclonal gammaglobulin interference. Serum free kappa/lambda chain ratio was also assessed.

RESULTS

Both serial dilutions and the ORTHO VITROS assay normalized serum phosphorus concentrations, suggesting the extremely high serum phosphorus concentrations measured by the Roche assay is due to interference from monoclonal gammaglobulin. Additionally, the patient's serum free kappa/lambda ratio was >100. Based on serum free kappa/lambda ratio, disease progression from SMM to MM was diagnosed.

CONCLUSIONS

Prompt and appropriate laboratory investigations ensure correct diagnosis of pseudohyperphosphatemia and help clinicians properly manage patients. To our knowledge, this patient is the first reported case of pseudohyperphosphatemia in patients with progression from SMM to MM.

Evidence for potential underestimation of clinical folate deficiency in resource-limited countries using blood tests

Although a low serum folate concentration is a useful biomarker of pure folate deficiency, the presence of vitamin B12 deficiency or hemolysis or both in individuals with low folate status predictably raises serum folate levels. Therefore, in resource-limited settings where dietary folate deficiency can coexist with vitamin B12 deficiency or malaria or both, the serum folate concentration can range from normal to high, leading to serious underestimation of tissue folate status. This review traces the genesis of an inappropriate overreliance on the serum folate concentration to rule out folate deficiency in vulnerable populations of women and children. Of significance, without due consideration of a chronically inadequate dietary folate intake, authors of influential studies have likely wrongly judged these populations to have an adequate folate status. Through repetition, this error has led to a dangerous entry into the contemporary medical literature that folate deficiency is rare in women and children. As a consequence, many millions of under-resourced women and children with mild to moderate tissue folate deficiency may have been deprived of folate replacement. This review uses historical documents to challenge earlier conclusions and re-emphasizes the need for contextual integration of clinical information in resource-limited settings.

Tumour genesis syndrome: severe hypophosphatemia and hypokalemia may be ominous presenting findings in childhood acute myeloid leukaemia

We report a 16-year-old girl who was diagnosed with acute leukaemia and a marked leucocytosis >200 × 10⁹/L. She presented with marked hypophosphatemia, hypokalemia, acute renal failure and acute respiratory failure. These electrolytes disturbances may indicate rapid tumour genesis. These ominous findings required urgent treatment to halt the crises of rapid leukemic cell proliferation.

CONCLUSION

Mark hypophosphatemia and hypokalemia may be presenting electrolyte abnormalities in a patient with acute leukaemia, and these may be indicators of aggressive tumour genesis. What is known: • Mild electrolyte disturbances are common in oncology patients • Tumour lysis syndrome is well recognized by paediatriaticians What is new: • Life-threatening hypophosphatemia is an uncommon presentation • These electrolytes disorders may indicate an aggressive tumour genesis process even at presentation and require urgent treatment.

Detecting paraprotein interference on a direct bilirubin assay by reviewing the photometric reaction data

BACKGROUND

The direct bilirubin (D-Bil) assay on the AU Beckman Coulter instrumentation can be interfered by paraproteins, which may result in spurious D-Bil results. In a previous work, we took advantage of this fact to detect this interference, thus helping with the identification of patients with unsuspected monoclonal gammopathies. In this work, we investigate the possibility to detect interference based on the review of the photometric reactions, regardless of the D-Bil result.

METHODS

The D-Bil assay was carried out in a set of 2164 samples. It included a group of 164 samples with paraproteins (67 of which caused interference on the assay), as well as different groups of samples for which high absorbance background readings could also be expected (i.e. hemolyzed, lipemic, or icteric samples). Photometric reaction data were reviewed and receiver operating characteristics (ROC) curves were used to establish a cut-off for absorbance that best discriminates interference.

RESULTS

The best cut-off was 0.0100 for the absorbance at the first photometric point of the complementary wavelength in the blank cuvette. Once the optimal cut-off for probable interference was selected, all samples analyzed in our laboratory that provided absorbance values above this cut-off were further investigated to try to discover paraproteins. During a period of 6 months, we detected 44 samples containing paraproteins, five of which belonged to patients with non-diagnosed monoclonal gammopathies.

CONCLUSIONS

Review of the photometric reaction data permits the systematic detection of paraprotein interference on the D-Bil AU assay, even for samples for which reasonable results are obtained.

In control? IQC consensus and statutory regulation

Purpose - Internal quality control (IQC) represents an essential risk management tool within the total testing pathway (TTP) that contributes to the overall objective of assuring the quality of results produced in medical laboratories. Controlling analytical phase quality alone requires significant expertise and input by scientifically trained staff. This effort has escalated exponentially following the publication of the International Organisation for Standardisation (ISO)15189:2012 requirements for quality and competence in medical laboratories. The reported inconsistency and diversity to IQC approaches in diagnostic laboratories is definitive evidence that international guidance in IQC programme design and implementation is long overdue. The paper aims to discuss these issues. Design/methodology/approach - Herein, the authors define, describe and critically examine the essential elements four stages of an IQC programme and suggest a template to inform both design and ease of implementation. For practical application, the authors have stratified the proposed methodology into four stages: staff education and training; IQC material; IQC targets; and IQC procedure, and provide recommendations that meet ISO15189:2012 requirements. Findings - These recommendations are informed by the published literature together with the collective experience working in clinical biochemistry and diagnostic endocrinology laboratories. The authors note that the laboratory staff's effort on IQC is a continuous process, driven by changes within each IQC stage, in response to risk analysis, maximising economic value or through professional leadership and central to IQC programme implementation and delivery. Practical implications - The authors offer a template that laboratories can use to inform the design and implementation of their IQC programme. Originality/value - The proposed IQC programme is user friendly, flexible and pragmatic with the potential to harmonise practice. The authors have provided a template to potentially harmonise IQC practice nationally. Given the central and critical role that IQC practice plays in ensuring the quality of patient results' importance, the authors contend that the time has come for international consensus and statutory regulation regarding the minimally acceptable criteria for its implementation, monitoring and review.

Analytical interference by monoclonal immunoglobulins on the direct bilirubin AU Beckman Coulter assay: the benefit of unsuspected diagnosis from spurious results

BACKGROUND

Monoclonal (M) components can interfere with the direct bilirubin (D-Bil) assay on the AU Beckman Coulter instrumentation and produce spurious results, such as D-Bil values greater than total bilirubin (T-Bil) or very low/negative D-Bil values. If properly detected, this interference may uncover undiagnosed patients with monoclonal gammopathy (MG).

METHODS

We investigated the interference rate on the D-Bil AU assay in serum samples known to contain M proteins along with their isotype and described the protocol set up in our laboratory to help with the diagnosis of MG based on D-Bil spurious results as first indication.

RESULTS

During a period of 4 years, 15.4% (345 of 2235) of serum samples containing M immunoglobulins produced erroneous D-Bil results, although no clear relationship between the magnitude or isotype of the M component and interference could be found. In total 22 new patients were diagnosed with MG based on the analytical artefact with the D-Bil as first indication.

CONCLUSIONS

The D-Bil interference from MG on the Beckman AU analysers needs to be made known to laboratories in order to prevent clinical confusion and/or additional workup to explain the origin of anomalous results. Although this information may not add to the management of existing patients with serum paraproteins, it can benefit patients that have not been diagnosed with MG by triggering follow up testing to determine if M components are present.

The pH of chemistry assays plays an important role in monoclonal immunoglobulin interferences

Objectives

Immunoglobulin paraproteins can interfere with multiple chemistry assays. We want to investigate the mechanisms of immunoglobulin interference.

Design and methods

Serum samples containing paraproteins from the index patient and eight additional patients were used to investigate the interference with the creatinine and total protein assays on the Beckman Coulter AU5400/2700 analyzer, and to determine the effects of pH and ionic strength on the precipitation of different immunoglobulins in these patient samples.

Results

The paraprotein interference with the creatinine and total protein assays was caused by the precipitation of IgM paraprotein in the index patient's samples under alkaline assay conditions. At extremely high pH (12–13) and extremely low pH (1–2) and low ionic strength, paraprotein formed large aggregates in samples from the index patient but not from other patients.

Conclusions

The pH and ionic strength are the key factors that contribute to protein aggregation and precipitation which interfere with the creatinine and total protein measurements on AU5400/2700. The different amino acid sequence of each monoclonal paraprotein will determine the pH and ionic strength at which the paraprotein will precipitate.

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Investigation of the cause of IgM paraprotein interference with creatinine assay.

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Paraprotein precipitation under assay conditions caused the interference.

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Identified The pH of chemistry assays is a key factor causing paraprotein precipitation.

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Results showed that not all paraproteins precipitate under the same assay conditions.

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Different paraproteins react differently to changes in pH and ionic strength.

Deficient copper concentrations in dried-defatted hepatic tissue from ob/ob mice: A potential model for study of defective copper regulation in metabolic liver disease

Ob/ob mice provide an animal model for non-alcoholic fatty liver disease/non-alcoholic steatohepatitis (NAFLD/NASH) in patients with obesity and type-2 diabetes. Low liver copper has been linked to hepatic lipid build-up (steatosis) in animals with systemic copper deficiency caused by low-copper diets. However, hepatic copper status in patients with NAFLD or NASH is uncertain, and a validated animal model useful for the study of hepatic copper regulation in common forms of metabolic liver disease is lacking. Here, we report parallel measurements of essential metal levels in whole-liver tissue and defatted-dried liver tissue from ob/ob and non-obese control mice. Measurements in whole-liver tissue from ob/ob mice at an age when they have developed NAFLD/NASH, provide compelling evidence for factitious lowering of copper and all other essential metals by steatosis, and so cannot be used to study hepatic metal regulation in this model. By marked contrast, metal measurements in defatted-dried liver samples reveal that most essential metals were actually normal and indicate specific lowering of copper in ob/ob mice, consistent with hepatic copper deficiency. Thus ob/ob mice can provide a model useful for the study of copper regulation in NAFLD and NASH, provided levels are measured in defatted-dried liver tissue.

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Ob/ob mice develop hepatic copper deficiency.

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Copper deficiency develops alongside NAFLD/NASH.

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Metal measurements in whole tissue are impacted by infiltrating fat.

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Levels of all essential metals are lower in ob/ob mice when measured in whole liver.

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After fat extraction, metal levels are normal, with the exception of copper.

Diagnostic accuracy of serum glypican-3 for hepatocellular carcinoma: a systematic review and meta-analysis

OBJECTIVE

Many individual studies have evaluated the diagnostic efficiency of serum glypican-3 (GPC-3) for diagnosing hepatocellular carcinoma (HCC), but the results have been inconsistent. The aim of present study was to meta-analyze the overall diagnostic accuracy of serum GPC-3 for diagnosing HCC.

DESIGN AND METHODS

English language studies which evaluated the diagnostic performance of GPC-3 and published before March 22, 2013 were retrieved. The quality of the studies was assessed by revised QUADAS tools. The performance characteristics were pooled and determined by random-effects models.

RESULTS

Twelve studies with a total of 898 HCC patients and 835 non-HCC patients were included. For the studies in which the majority of reference participants had HBV or HCV infections, the overall diagnostic sensitivity and specificity were 0.53 (95% CI: 0.49-0.57) and 0.77 (95% CI: 0.74-0.81), respectively. The area under summary receiver operating characteristic (sROC) curves (AUC) was 0.82. The major design deficiencies of included studies were differential verification bias, and a lack of clear exclusion and inclusion criteria.

CONCLUSIONS

GPC-3 has moderate diagnostic accuracy for HCC. Due to the design limitations, results in published studies should be carefully interpreted. In addition, more well-designed studies with large sample sizes should be performed to rigorously evaluate the diagnostic value of the GPC-3.

Factitious Biochemical Reports which are Caused Due to Paraproteinaemia in Multiple Myeloma - A Case Report

Factitious biochemical reports result in the misguiding of clinicians, unnecessary retesting, wrong diagnoses and incorrect treatments. A vigilant biochemist identifies these factitious biochemical reports and alerts the clinician regarding the proper interpretation of the biochemical reports, thus preventing a misdiagnosis and an incorrect treatment. We are presenting a case report of a multiple myeloma patient who presented with factitious biochemical reports which were caused due to paraproteinaemia. In the present case, the patient presented with an underestimation of urea and creatinine, an underestimation of sodium, low albumin levels and high phosphate levels. On repeating the same tests after dilutions and deproteinizing, the effects of the paraproteins on the above mentioned tests were reduced. Thus, from the observations of our study, we suggest that the interference by paraproteinaemia can be reduced by analyzing the biochemical parameters after dilution and deproteinization.

The CCLM contribution to improvements in quality and patient safety

Clinical laboratories play an important role in improving patient care. The past decades have seen unbelievable, often unpredictable improvements in analytical performance. Although the seminal concept of the brain-to-brain laboratory loop has been described more than four decades ago, there is now a growing awareness about the importance of extra-analytical aspects in laboratory quality. According to this concept, all phases and activities of the testing cycle should be assessed, monitored and improved in order to decrease the total error rates thereby improving patients’ safety. Clinical Chemistry and Laboratory Medicine (CCLM) not only has followed the shift in perception of quality in the discipline, but has been the catalyst for promoting a large debate on this topic, underlining the value of papers dealing with errors in clinical laboratories and possible remedies, as well as new approaches to the definition of quality in pre-, intra-, and post-analytical steps. The celebration of the 50th anniversary of the CCLM journal offers the opportunity to recall and mention some milestones in the approach to quality and patient safety and to inform our readers, as well as laboratory professionals, clinicians and all the stakeholders of the willingness of the journal to maintain quality issues as central to its interest even in the future.

Clinical quality indicators in laboratory medicine

Clinical laboratories have an important role in improving patient care. The past decades have seen enormous changes with unpredictable improvements in analytical performance, range of tests and capacity to manage large volumes of work. At the same time, there has been a dramatic fall in the rate of laboratory errors. However, there is now a growing awareness that the testing process includes the time before samples reach the laboratory and after reports have been printed and that these areas need to be included in the quality assessment of the total testing process. Laboratory quality should include a focus on patient safety and clinical effectiveness. Services should be patient-centred, timely, efficient and equitable, and finally, should be moulded to ensure optimal outcomes. There is a need to define quality indicators that will ensure there is appropriate choice and selection of tests, use of the appropriate assay standardization and the correct interpretation of the assay results at the appropriate time. These are the areas in which a quality laboratory can, and should, now involve itself.

The detection and prevention of errors in laboratory medicine

The last few decades have seen a significant decrease in the rates of analytical errors in clinical laboratories. Evidence demonstrates that pre- and post-analytical steps of the total testing process (TTP) are more error-prone than the analytical phase. Most errors are identified in pre-pre-analytic and post-post-analytic steps outside of the laboratory. In a patient-centred approach to the delivery of health-care services, there is the need to investigate, in the TTP, any possible defect that may have a negative impact on the patient. In the interests of patients, any direct or indirect negative consequence related to a laboratory test must be considered, irrespective of which step is involved and whether the error depends on a laboratory professional (e.g. calibration/testing error) or non-laboratory operator (e.g. inappropriate test request, error in patient identification and/or blood collection). Patient misidentification and problems communicating results, which affect the delivery of diagnostic services, are recognized as the main goals for quality improvement. International initiatives aim at improving these aspects. Grading laboratory errors on the basis of their seriousness should help identify priorities for quality improvement and encourage a focus on corrective/preventive actions. It is important to consider not only the actual patient harm sustained but also the potential worst-case outcome if such an error were to reoccur. The most important lessons we have learned are that system theory also applies to laboratory testing and that errors and injuries can be prevented by redesigning systems that render it difficult for all health-care professionals to make mistakes.