Errors in Clinical Biochemistry Laboratory

An observational study was done for a period of 6 months from 1st January, 2023 to 30th June, 2023 in the clinical biochemistry laboratory at GCS Medical College, Hospital and Research Centre. The study delved into pre-analytical errors within clinical biochemistry laboratories, focusing on error types, their prevalence, and potential impact. The study aimed to identify and quantify errors occurring in the pre-analytical phase, spanning from sample collection to report generation. Among the recorded errors (n=50), the most frequent was insufficient sample volume, signifying a pressing concern. Another prevalent error was Tests Not Mentioned or Add-on Testing, accounting for 26% of all errors, potentially disrupting workflow. The research also highlighted additional errors, including hemolysis, clotted samples, contamination from infusion routes, and lipemic samples. The study underscored the significance of addressing these errors to ensure accurate and reliable test results, thereby enhancing patient care. Overall, it provided valuable insights into the landscape of pre-analytical errors in clinical biochemistry, emphasizing the need for improved procedures, enhanced training, and effective communication to enhance the quality and precision of laboratory testing and, ultimately, patient care.

Background: Total testing process (TTP) in biochemistry laboratory is composed of 3 phases; pre-analytical, analytical and post-analytical. Errors in these phases can lead to erroneous results, hence, compromise the patient management. Objective: 1. To document the nature and determine the frequency of errors in all the three phases of TTP using quality indicators (QI). 2. Applying sigma metrics to data obtained. Study Design: Prospective cross-sectional study. Settings: Clinical Biochemistry Laboratory, at AIMSR, Bathinda, Punjab India. Duration: June 2023 to Nov 2023. Methods: Quality indicators were used to screen errors in requisition forms and samples received in clinical chemistry for analysis. Results: During analysis of 22320 samples, a total of 132 samples were unsuitable for testing and reporting, this resulted in 0.59% of rejection. Out of total 132 rejections, 99 (75%) were in pre-analytical phase, 11 (8.3%) in analytical phase and 22 (16%) in post-analytical phase. The Sigma score of 5 is seen which is acceptable. Conclusion: The preanalytical error is the most common error. Error is unacceptable in the medical field hence training program for the laboratory and non-laboratory personnel involved should be conducted.

Resultados de la implantación de un sistema de control de calidad para los glucómetros del Área Hospitalaria Virgen Macarena, con conexión on-line al Laboratorio de Bioquímica Clínica, durante el período 2003–2007 ,

Background: Laboratory request forms are essential communication tool between the clinicians and laboratory personnel. In view of the meagerness of studies exploring request forms as a part of preanalytical errors, we planned to evaluate the request forms received at the clinical biochemistry laboratory. Objective: The aim of this study was to evaluate the adequacy of the details of laboratory request forms that had been submitted to biochemistry department. Materials and Methods: This lab audit was carried out at the clinical biochemistry laboratory of a tertiary care teaching hospital. The forms Laboratory request forms were segregated to evaluate the extent of completion of each form, completion of the columns, legibility of the clinician`s handwriting. The results were expressed in percentages. Results: A total of three thousand and fifty (3050) request forms were analyzed. The location of the patient and referring department were missing in 35.3% and 29.4% of the forms respectively. Provisional diagnosis was provided only in 53.3% of the request forms. Conclusion: This study concludes that the location of the patient, probable diagnosis, medical officer`s signature had not been entered in the request forms. As laboratory plays a crucial role in the patient diagnosis, incomplete data in the request form might significantly affects the lab service which in turn affects the patient’s health care system. The standard of filling of laboratory request forms needs to improve to provide a high quality lab service.

Introduction: With advance in technology, many instruments with wide variety of principle or technologies are available in market and in laboratory to conduct sample processing in time bound period. To fulfill the laboratory quality goal, it is essential that result matching be obtained in all used biochemical analysers for examinations. Documented evidence of method/instrument comparison can be used in future for quality improvement purposes. Aim: To assess and compare equivalence and harmonisation in glucose results produce by ERBA XL-640 vs ERBA XL-1000 in clinical biochemistry laboratory. Materials and Methods: A comparative study was carried out by results comparison of glucose measurements obtained in two automated systems ERBA XL-640 and ERBA XL-1000 in Clinical Biochemistry laboratory at Surat Municipal Institute of Medical Education and Research between June 2021 to October 2021, based on protocol EP09-3A of result harmonisation and review article-method comparison. The results value were compared according to the total allowable error in Clinical Laboratory Improvement Amendments of 1988 (CLIA’88). Results were analysed by visual and quantitative analysis method Regression analysis and Bland-Altman plot, Method evaluation chart (Normalised MEDx chart). Results: Total of 48 samples were run within the batches and between the batches and quantitative analysis of difference was done. It is acceptable at medical decision level 40 mg/dL, 120 mg/dL and 180 mg/dL with comparison to total allowable error. Conclusion: The present study concluded that the comparison of ERBA XL-640 and ERBA XL-1000 for glucose examination by end point method {Glucose Oxidase-Peroxidase (GOD-POD) method} is acceptable and can be used interchangeably without repeat at major clinical decision levels.

42 - The clinical biochemistry laboratory

The National Academy of Clinical Biochemistry (NACB) Laboratory Medicine Practice Guidelines for Use of Tumor Markers are intended to encourage more appropriate use of tumor marker tests by primary care physicians, hospital physicians and surgeons, specialist oncologists, and other health professionals. This introduction accompanies the e-publication of 2 reports summarizing NACB Quality Requirements for use of tumor markers in clinical practice (1) and NACB Guidelines for use of tumor markers in testicular, prostate, colorectal, breast, and ovarian cancers (2). Two further reports will follow, summarizing the NACB Guidelines for use of tumor markers in liver, pancreatic, gastric, bladder, and cervical cancers and the NACB Guidelines for use of tumor markers in parathyroid, thyroid, neuroendocrine and lung cancers, monoclonal gammopathies, and melanoma. Here we report the updating and extension of practice guidelines first proposed in 2002 (3). Undertaken under the direction of a steering committee appointed by the NACB (Table 1⇓ ), this process involved consideration of 16 specific cancer sites, together with quality requirements for well-established tumor markers and tumor markers being developed by use of new technologies (Table 2⇓ ). With its wide scope, this project is one of the most comprehensive and complex of its type to date. The draft guidelines were posted on the NACB website in July 2005 and were presented as an EduTrak at the 2005 Joint AACC/IFCC Annual meeting in Orlando, Florida. Informed comment was also actively sought from individuals, organizations, and other interested parties. View this table: Table 1. Steering committee for NACB Laboratory Medicine Practice Guidelines on Use of Tumor Markers in clinical practice. View this table: Table 2. Subjects and subcommittee members for NACB Laboratory Medicine Practice Guidelines on Use of Tumor Markers in clinical practice. Nineteen subcommittees developed draft guidelines (Table 2⇑ ). Subcommittee members included individuals with extensive expertise in the science, technology, and clinical practice …

A working group from health occupational and clinical biochemistry services on French sites has issued essential data sheets on the guidelines to follow in managing the victims of a criticality accident. Since the priority of the medical management after a criticality accident is to assess the dose and the distribution of dose, some dosimetric investigations have been selected in order to provide a prompt response and to anticipate the final dose reconstruction. Comparison exercises between clinical biochemistry laboratories on French sites were carried out to confirm that each laboratory maintained the required operational methods for hair treatment and the appropriate equipment for 32P activity in hair and 24Na activity in blood measurements, and to demonstrate its ability to rapidly provide neutron dose estimates after a criticality accident. As a result, a relation has been assessed to estimate the dose and the distribution of dose according to the neutron spectrum following a criticality accident.

In a critically ill patient, when an arterial blood sample is processed on an arterial blood gas (ABG) analyzer, it also measures electrolytes apart from analyzing the blood gases. The turnaround time for ABG analysis is way too less compared to the conventional electrolyte analysis with a serum sample. This study intends to investigate whether values of electrolytes estimated in arterial blood can substitute the routinely practiced method. This is a retrospective cross-sectional study. The source of data is patients' reports of serum electrolytes and ABG analysis from the Clinical Biochemistry laboratory, CIMS Teaching Hospital, Chamarajanagar between January and June 2021. The electrolytes report of 200 patients from whom both arterial and venous blood samples were sent to the Clinical Biochemistry laboratory on the same day and at the same time for analysis were selected. The data was compiled, compared, and correlated using a suitable statistical tool. The mean and standard deviation of sodium (135.62 ± 5.20 in venous vs 134.08 ± 8.49 in arterial blood), potassium (4.20 ± 0.64 vs 3.80 ± 0.75), and chloride (102.28 ± 4.99 vs 96.33 ± 8.11) were observed. However, when the concordance correlation coefficient and Bland-Altman plot analysis were made there was no agreement between electrolytes analyzed on serum in an autoanalyzer with that of ABG analyzer. We conclude that the electrolytes measured by a conventional autoanalyzer on a serum sample cannot be replaced by values analyzed on a blood gas analyzer. Devaki RN, Kasargod P, Roopa Urs AN, Chandrika N. A Retrospective Database Analysis to Investigate if Electrolytes in Venous Blood are Equivalent to the Levels in Arterial Blood. Indian J Crit Care Med 2024;28(5):442-446.

Chronic cholangitis in cats can be induced by liver fluke infestation. It is a rare disease and can be fatal if it is left untreated due to a number of complications including liver cancer. A 2.5-year-old–spayed female domestic shorthair cat with history of jaundice, vomiting and self-inflicted alopecia was brought to the University Veterinary Hospital. Blood and urine samples were sent to the Veterinary Haematology and Clinical Biochemistry Laboratory. Complete blood count results showed values within normal. The cat rather had persistent increases in liver enzymes and bilirubin throughout 1 week of hospitalisation, although she was treated empirically. Bilirubinuria was expected, and adequately concentrated urine was noted. Faecal sample submitted to the Veterinary Parasitology Laboratory during hospitalisation revealed the presence of liver fluke ova. The cat was treated with fenbendazole and other medications upon discharged, and the owner was advised to bring the cat for a visit for re-evaluation of liver enzymes and liver fluke ova.

Sigma methodology has become a valuable tool in clinical laboratories for assessing analytical performance and optimizing QC. However, the choice of total allowable error (TEa) sources significantly influences sigma calculation outcomes and can lead to inconsistent quality classifications. In this study, we aimed to evaluate how different TEa guidelines impact sigma metrics and internal quality control (IQC) strategies in order to highlight the need for harmonization in TEa selection. A prospective observational study was conducted over 3 months (April-June 2025) in the Clinical Biochemistry Laboratory at Bechir Hamza Children's Hospital. Sigma metrics were calculated for 14 routine analytes at 2 QC levels (level 1 and level 2) using internal and external QC data. Three TEa sources were used: CLIA 2025 (regulatory-based), Randox International Quality Assessment Scheme (RIQAS; peer group-based), and European Federation of Laboratory Medicine (EFLM; biological variation-based). IQC procedures were adapted based on Westgard sigma rules and flowcharts. Substantial variability in sigma metrics was observed across the 3 TEa guidelines. The same analyte could be classified as "world-class" under EFLM but "unacceptable" under RIQAS. Electrolytes (sodium, potassium, chloride) consistently exhibited poor performance across all guidelines. Visual tools, including radar and sigma charts, confirmed discrepancies. These differences significantly influenced the selection and complexity of IQC procedures. The choice of TEa guideline exerts a critical influence on sigma metrics and subsequent IQC planning. Current inconsistencies highlight the urgent need for standardized TEa criteria that are both clinically meaningful and practically achievable. Harmonization would improve comparability, optimize laboratory resources, and support evidence-based quality management in clinical laboratories.

Fluid and electrolyte disorders

With the development of new and sensitive techniques for detection of very minute quantities of biomolecules now it is possible to identify the changes in the levels of gene regulatory enzymes and other substances. Silver staining in SDS-PAGE (14). Radio receptor [RRA] and Radio immuno assays [RIA] (75) enzyme linked iummuno assays [ELISA] (76). Western; Northern and Southern blotting techniques (77,78) among others can detect upto picogram quantities. Cellular proteins such as cytoskeletal proteins, membrane bound proteins (37), chromatin associated proteins and gene regulatory enzymes which are not soluble in ordinary aqueous buffers and are non-secretory in nature can now be detected in needle biopsies by the above mentioned techniques. Steroid hormone receptor assays are routinely done in many clinical biochemistry laboratories in order to decide whether the tumor from breast, cervix or uterus are hormone dependent or not.

Background: Preeclampsia is a clinical condition in which the patient is suffering from hypertension and proteinuria, which may be associated with pathological edema. There are multiple systems involved in pre-eclampsia which is the main culprit to complicate the pregnancy. In developing nations, approximately 4–18% of pregnancies are complicated by preeclampsia which is a major cause of morbidity and mortality globally. It does not affect pregnant females only, but may be life-threatening for growing fetuses too. If we consider the mortality in all pregnant females, about 10–15% of maternal deaths are due to pre-eclampsia. Aims and Objectives: The main objective of this study is to compare the serum calcium, magnesium, sodium and potassium level in preeclampsia patients and normal pregnant women. Materials and Methods: After taking written consent from the patients, randomly 50 pregnant females diagnosed by a gynecologist as suffering from preeclampsia were selected and for the control group 50 pregnant females who came for routine checkups were selected. 5 ml of blood was collected in the clot activator tube. The samples were analyzed for serum calcium, magnesium, sodium, and potassium on a fully automated biochemistry analyzer ”Erba XL 640” in HiTech, clinical biochemistry laboratory, B.J medical college, Ahmedabad. Results: The result showed a decreased level of serum calcium, magnesium, sodium, and potassium in the study group compared to the control group. The S. calcium level was (7.624 ± 0.84) and (8.52 ± 0.80) mg/dl in the study and control groups respectively. The S. magnesium level in the study and control were (1.47 ± 0.25) and (1.79 ± 0.18) mg/dl, respectively. S. sodium levels were (131.46 ± 6.96) and (139.92±7.86) mEq/L in the study and control groups, respectively. And the level of S. potassium in the study and control groups was (3.39 ± 0.52) and (3.67 ± 0.38) mEq/L, respectively. All the parameter values are significantly lower in a study group in comparison to control group patients (P < 0.001). Conclusion: From our study, we have concluded that the serum level of some parameters such as calcium, magnesium, sodium, and potassium was significantly decreased in patients suffering from preeclampsia. We can also conclude that these parameters can be used as a biomarker for the diagnosis of preeclampsia.

Introduction: Uric acid is an important antioxidant that contributes for around 60% of free radical scavenging capacity of serum. Its role has been controversial in type 2 diabetes mellitus. Earlier studies have reported that renal disease leads to elevation of uric acid in DM, but recently high uric acid levels are reported to be risk factor for the development of diabetes mellitus. Aim of our study is to compare uric acid in type 2 DM with renal disease with non-diabetics and also to compare its levels among patients in different stages of diabetic nephropathy. Methodology: The case control study was conducted in medical college hospital in coastal Karnataka. Data of serum uric acid, renal profile and demographic profiles of 89 type 2 diabetes mellitus patients was collected from the clinical biochemistry laboratory in the year 2016. Data of 80 non-diabetic controls was taken. Transasia XL-640 was used for the estimation.Estimated GFR (eGFR) was calculated using MDRD formula. Results: We found an elevation in uric acid and creatinine levels, extremely significantly lower eGFR in diabetics (P = 0.0195, P=0.0078 and P =0.0001respectively).Odd’s ratio was 3.128 between uric acid and diabetic nephropathy. A highly significant (P < 0.0016) differences was observed in uric acid levels among patients of different stages of diabetic nephropathy. Conclusion: Hyperuricemia was found in diabetic nephropathy patients. There was a significant difference in uric acid was observed among different stages of nephropathy. However causal relationship is inclusive. Prospective studies need to be designed with a serial monitoring of uric acid, GFR and microalbunuria in diabetics till the development of nephropathy to establish which the cause is and which is effect among these two factors (uric acid and diabetic nephropathy. Keywords: Uric acid, eGFR, Diabetes mellitus, Nephropathy