Annals of Clinical Biochemistry, Ahead of Print.
Combined or mixed hyperlipidaemia is characterised by hypercholesterolaemia together with high triglyceride concentrations. It is found in approximately 1 in 100 people in the United Kingdom. Most cases are secondary to an underlying condition such as the metabolic syndrome, diabetes mellitus (especially poorly controlled) or individuals with a high alcohol intake. Mixed hyperlipidaemia is also a feature of some primary hyperlipidaemia conditions such familial combined hyperlipidaemia (FCH) or type III hyperlipidaemia (dysbetalipoproteinaemia). One differential diagnosis for mixed hyperlipidaemia that can easily be overlooked is a patient with an underlying diagnosis of familial hypercholesterolaemia (FH) who also has a hypertriglyceridaemia due to any other cause. Those patients may have very high total and low-density lipoprotein cholesterol concentrations (LDL-C) with a moderately elevated triglyceride concentration. In this article, we report 4 cases of familial hypercholesterolaemia, confirmed by genetic testing, in patients initially presenting with hypertriglyceridaemia in addition to high total cholesterol and LDL-C. This article discusses the diagnostic challenges associated with this presentation and highlights the key role of directly measuring LDL-C to aid diagnosis in these specific situations.

Annals of Clinical Biochemistry, Ahead of Print.
Rheumatoid arthritis (RA) is a chronic, systemic, autoimmune condition that primarily affects the joints and periarticular soft tissues. In the past two decades, the discovery of new biomarkers has contributed to advances in the understanding of the pathogenesis and natural history of RA. These biomarkers, including genetic, clinical, serological and imaging biomarkers, play a key role in the different stages and aspects of RA, from the so called ‘pre-clinical RA’, which is characterized by subclinical pathological events, such as autoimmunity and inflammation, to diagnosis (including differential diagnosis), treatment decision making and disease monitoring.This review will provide an overview on the current role of traditional and newer biomarkers in the main aspects of RA management, from the identification of individuals ‘at-risk’ of RA who are likely to progress to clinically evident disease, to ‘early’ diagnosis of RA, prognosis, precision medicine, and prediction of response to treatment.

Annals of Clinical Biochemistry, Ahead of Print.
BackgroundTo determine delta check limits for immunoglobulins and complements in outpatients and inpatients based on patient data and biological variation due to the lack of relevant studies.MethodsPatient data for IgA, IgG, IgM, IgE, C3, and C4 from 1 January 2022 to 31 December 2023 was collected from laboratory information system (LIS) in our clinical laboratory of Wuhan Union Hospital, which includes both outpatients and inpatients. The delta difference (DD), delta percent change (DPC), and reference change value (RCV) were calculated based on patient data and biological variation.ResultsFor DDs, there are significant differences between outpatients and inpatients in C4, IgE, IgG, and IgM. For DPCs, the corresponding analytes which are significantly different are C3, C4, IgE, IgG, and IgM. Two sources of CVI to calculate the RCV of IgA, IgG, IgM, C3, and C4 were applied in this study, which revealed that two kinds of RCVs based on different biological variation databases are similar to each other, but both were smaller than delta check limits based on patient data, except for C4.ConclusionsThe delta check is a useful tool to monitor potential errors which may occur in total testing process. We hope our findings could be helpful for future studies focused on delta checks in immunological analytes.

Annals of Clinical Biochemistry, Ahead of Print.
BackgroundThe escalating prevalence of diabetes underscores the need for precise diagnostic tools to facilitate effective management. Hemoglobin A1c (HbA1c) is a crucial biomarker for long-term glycemic control in diabetic patients. Point-of-care testing (POCT) for HbA1c offers rapid, accessible alternatives to conventional laboratory methods, but uncertainties persist regarding the accuracy and reliability of POCT assays.MethodsThis study evaluates the analytical performance of two boronate-affinity based HbA1c POCT assays, the GreenCare A1c and Cera-Stat HbA1c. Various analytical parameters including precision, linearity, comparison, and accuracy are assessed following guidelines from Clinical and Laboratory Standards Institute (CLSI), with results applied to certification criteria from the National Glycohemoglobin Standardization Program (NGSP) and International Federation of Clinical Chemistry and Laboratory Medicine (IFCC). Furthermore, 52 and 13 frozen EDTA whole blood samples were respectively used for additional evaluation of accuracy and interference due to Hb variants for the GreenCare A1c assay.ResultsBoth GreenCare and Cera-Stat demonstrated good precision (repeatability CV% 1.5-1.9 and total imprecision CV% 1.6–2.2), linearity (R2 = 0.9996 & 0.9990), and correlation (r = 0.982 & 0.978) with an established HbA1c analyzer, the Bio-Rad D100. The GreenCare also exhibited good accuracy with frozen EDTA samples with known HbA1c values. Both assays met the certification criteria from NGSP and IFCC, classifying them as “standard” according to IFCC model for quality targets for HbA1c.ConclusionsThis evaluation affirms the reliability of GreenCare and Cera-Stat POCT assays for HbA1c measurements, which can potentially reduce unnecessary referrals and enhance the overall quality of diabetes diagnosis and treatment.

Annals of Clinical Biochemistry, Ahead of Print.
BackgroundML predictive models have shown their capability to improve risk prediction and assist medical decision‐making, nevertheless, there is a lack of accuracy systems to early identify future rapid CKD progressors in Colombia and even in South America.ObjectiveThe purpose of this study was to develop a series of interpretable machine learning models that predict GFR at 6-months, 9-months, and 12-months.Study Design and SettingOver 29,000 CKD patients stage 1 to 3b (estimated GFR, <60 mL/min/1.73 m2) with an average of 3-year follow-up data were included. We used the machine learning extreme gradient boosting (XGBoost) to build three models to predict the next eGFR. Models were internally and externally validated. In addition, we included SHapley Additive exPlanation (SHAP) values to offer interpretable global and local prediction models.ResultsAll models showed a good performance in development and external validation. However, the 6-months XGBoost prediction model showed the best performance in internal (MAE average = 6.07; RSME = 78.87), and in external validation (MAE average = 6.45, RSME = 18.94). The top 3 most influential features that pushed the predicted eGFR value to lower values were the interpolated values for eGFR and creatinine, and eGFR at baseline.ConclusionIn the current study we have developed and validated machine learning models to predict the next eGFR value at different intervals. Furthermore, we attempted to approach the need for prediction explanation by offering transparent predictions.

Annals of Clinical Biochemistry, Ahead of Print.

Annals of Clinical Biochemistry, Ahead of Print.
We introduce a 16-year-old female who presented with tender cervical lymphadenopathy, prolonged fever, and hypothyroidism. After excluding common causes of fever of unknown origin, a surgical biopsy of cervical lymph nodes revealed Kikuchi-Fujimoto disease. The patient showed improvement with a short-term course of NSAIDs. An increased titre of thyroperoxidase antibody led to a diagnosis of Hashimoto’s thyroiditis during stable condition. This report underscores the importance of considering Kikuchi-Fujimoto disease in the differential diagnosis of prolonged fever of unknown origin with lymphadenopathy and highlights the association with Hashimoto’s thyroiditis, advocating for vigilance regarding hypothyroidism in long-term follow-up after Kikuchi-Fujimoto disease recovery.

Annals of Clinical Biochemistry, Ahead of Print.
BackgroundLysophosphatidylethanolamines (lyso-PEs) are the partial hydrolysis products of phosphatidylethanolamine. Although lyso-PEs are important biomarkers in various diseases, their determination is limited by the lack of simple and efficient quantification methods. This study aims to develop an improved quantitative method for the determination of lyso-PEs and its application to an epidemiological study.MethodsSingle reaction monitoring channels by collision-induced dissociation for seven lyso-PEs were established using liquid chromatography-tandem mass spectrometry. Plasma lyso-PEs were extracted with a single-phase method using an isotopically labelled internal standard for quantification. The proposed method was adopted to define lyso-PEs in plasma samples of children aged 9–12 years living in Sapporo, Japan.ResultsThe limit of detection and limit of quantification for each lyso-PE ranged between 0.001–0.015 and 0.002–0.031 pmol/μL, respectively. Recoveries were found to be > 91% for all the species. The analysis results of children’s plasma showed that the total lyso-PE concentrations in boys (n = 181) and girls (n = 161) were 11.53 and 11.00 pmol/μL (median), respectively. Participants were further classified by the percentage of overweight and subgrouped as underweight (n = 12), normal range (n = 292), or overweight (n = 38). Interestingly, the reduction of lyso-PE 16:0 and increased lyso-PE 22:6 were observed in overweight children compared with normal range (Fold change: 0.909 and 1.174, respectively).ConclusionsThis study successfully established a simple quantitative method to determine lyso-PE concentrations. Furthermore, our method revealed the possible relation between plasma lyso-PEs and overweight status.

Annals of Clinical Biochemistry, Ahead of Print.
BackgroundThe detection of deficiencies in B12 and folate children is important. However, despite the availability of various markers to assess B12 and folate metabolism, there are limited studies describing the reference intervals (RIs) and changes during growth and development for these markers in healthy children.MethodsUsing samples collected from 378 children aged 30 days–< 18 years, we derived continuous RIs for holotranscobalamin, homocysteine and red cell folate.ResultsThe lower RI for holotranscobalamin was lowest at birth, rising during early childhood and then declining following ages 4–6 years whereas red cell folate was highest early in life and then declined steadily towards adulthood. Total homocysteine, reflective of both B12 and folate status was elevated early in life, reaching a nadir at age 2 and then increasing towards adulthood.ConclusionsContinuous central 95th percentile RI for holotranscobalamin, homocysteine and red cell folate for children ages 30 days to <18 years were established. Each marker shows dynamic changes throughout childhood and adolescence which will assist clinicians in more appropriately assessing B12 and folate status in this population.

Annals of Clinical Biochemistry, Ahead of Print.
BackgroundFaecal calprotectin is an inflammatory marker used to triage patients for further investigation with suspected inflammatory bowel disease (IBD). Our current method requires faecal samples be sent to the laboratory, where calprotectin is extracted before analysis. This is a time-consuming, potential bottleneck in the pathway. We have recently evaluated the OC-SENSOR PLEDIA fCAL method that uses the same sampling device as used in some bowel cancer screening and symptomatic colorectal cancer programmes that detect faecal haemoglobin. The below study is a comparison of the OC-FCa method with the BÜHLMANN fCAL Turbo which is used routinely within BSPS.Method150 homogenised and 110 non-homogenised faecal samples were loaded into OC-Sampling Bottle 3 and BÜHLMANN CALEX cap sampling devices. The samples were then analysed on their respective systems according to manufacturer’s instructions.ResultsThe OC-FCa assay had a mean positive bias of 67.3% (homogenised) and 88.4% (non-homogenised). Homogenised samples showed substantial agreement between the methods for normal (<50 µg/g) and elevated (150+µg/g) risk categories (k = 0.794, k = 0.788, respectively) and moderate agreement for borderline (51–150 µg/g) (k = 0.25) according to the current Berkshire and Surrey Pathology Service (BSPS) guidelines. Non-homogenised samples had none to slight agreement for normal and borderline values (k = 0.02 for both) and moderate agreement for elevated (k = 0.596).ConclusionThe OC-FCa method is a viable alternative for faecal calprotectin testing, but requires an adjustment to clinical cut-off values due to the lack of standardisation and strong positive bias. A clinical comparative study is required to assess the impact of patients collecting their own samples into the devices, as this may negate any potential degradation samples may exhibit during transit to the laboratory.

Annals of Clinical Biochemistry, Ahead of Print.
BackgroundExamining the distribution of biochemical and haematological tests in different age groups of rural population is necessary to ensure that health care facilities are equipped to address the prevalent health conditions and manage age-related illness effectively. Hence, this study is aimed at seeing the distributions of blood biochemical and haematological parameters in rural population.MethodsThis cross-sectional study investigated the distribution of 26 different haematological and biochemical parameters in longitudinal cohort study (Srinivaspura Aging, NeuoSenescence and COGnition - SANSCOG), from the villages of Srinivaspura, Kolar district, India. A total of 2592 participants (1240 males and 1352 females), aged ≥45 years who are cognitively healthy were included for the analysis. Mean, 2.5th, 5th, 25th, 50th, 75th, 95th and 97.5th percentiles were calculated for the entire sample. Additionally, median and percentiles were determined for both gender and age categories (45-54, 55-64, 65-74, and ≥75 years).ResultsWe observed the distinct distributions of various haematological and biochemical parameters, with elevated levels of glycaemic, lipid, liver, and thyroid parameters.ConclusionFindings revealed the notable variations from the established reference ranges, indicating the potential undiagnosed cases and highlighting the gaps in health awareness and health seeking behaviour.

Annals of Clinical Biochemistry, Ahead of Print.
BackgroundAs one of the most requested profiles of blood tests, there is a need for standardization among liver function tests (LFT). Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) are key markers of hepatocellular injury. ALT and AST are used to calculate a Fibrosis-4 (FIB-4) score for assessing liver fibrosis. Despite recommendations by the International Federation of Clinical Chemistry (IFCC) to include pyridoxal-5-phosphate in ALT and AST assay methodologies, most laboratories continue to omit this.MethodsData from the UK NEQAS for Clinical Chemistry Scheme, Distribution 1160 (November 2023), was reviewed to investigate variation in practice regarding liver blood tests in relation to ALT, AST and FIB-4. In addition, a series of questions audited laboratory practice in relation to liver enzymes.ResultsWide variation was seen in LFT profiles offered by laboratories, with 32 different combinations of tests used. The IFCC-recommended methods for ALT and AST are used by one-third of laboratories and give significantly higher results than non-IFCC methods. Laboratories using IFCC methods also reported significantly higher FIB-4 scores. Reference ranges and cut-offs for these tests also varied, and did not account for method-related differences in results.ConclusionsThe lack of standardization of LFTs can have a significant impact on patient care. The difference in results for ALT, AST and FIB-4 in laboratories not using IFCC-recommended methods may lead to misdiagnosis. This issue should be addressed by laboratories using methods including pyridoxal-5-phosphate. Until then, method-related reference ranges and cut-offs for ALT, AST and FIB-4 are required.

Annals of Clinical Biochemistry, Ahead of Print.
This is a case of a 61-year-old lady who presented to the lipid clinic with possible familial hypercholesterolaemia (Simon Broome Criteria). She was commenced on atorvastatin; however, 4 weeks later, she developed hepatitis, and therefore her atorvastatin was discontinued. Following that, her liver function tests normalized, and she was diagnosed with statin-induced hepatitis. Three years later, she was seen again in the lipid clinic with an uncontrolled lipid profile, and she was commenced on alirocumab, a Proprotein Convertase Subtilisin/Kexin type 9 (PCSK9) inhibitor. A few days later, she developed hepatitis, and subsequently, the alirocumab was discontinued. She underwent a liver biopsy, which confirmed that she had Autoimmune Hepatitis (AIH) with presumed superimposed drug injury. This is the first reported case of autoimmune hepatitis associated with alirocumab.

Annals of Clinical Biochemistry, Ahead of Print.

Annals of Clinical Biochemistry, Ahead of Print.
BackgroundThe Dutch guideline algorithm for the analysis of anaemia in patients of general practitioners (GPs) was programmed in a Clinical Decision Support system (CDS-anaemia) to support the process of diagnosing the cause of anaemia in the laboratory. This research aims to assess the supplementary benefit provided by the automated algorithm in various demographic categories, including different sexes, age groups and severities of anaemia, in comparison to the manual diagnostic approach employed by GPs.MethodsThis was a retrospective cohort study of 5399 primary care patients where the cause of anaemia was diagnosed by GPs with or without the aid of CDS-anaemia within the age groups 18–44, 45–64, 65–79 and 80 and older. Anaemia was defined according to the Dutch College of General Practitioners (DCGP) guideline. Causes of anaemia were based on the DCGP guidelines with the corresponding blood tests. By calculation of rate ratios and percentage differences of the determined cause of anaemia we evaluated the effect of the diagnostic algorithm.Results and conclusionThe percentage patients in which an underlying cause of anaemia was found increased 34 and 46 percentage points in males and females, respectively, when GPs were supported by CDS-anaemia compared to GPs who were not supported by CDS-anaemia. The highest increase in percentage points when CDS-anaemia was used, was found in younger- and middle-aged males and mild or moderate anaemia.

Annals of Clinical Biochemistry, Ahead of Print.