Electronic Journal of the International Federation of Clinical Chemistry and Laboratory Medicine最新文献

Background: ICAP describes ANA patterns from AC- 0 to AC-29. They are further marked for competent or expertise reporting depending on ease of identification. There are some debatable patterns in ICAP which share similar features with a few others yet have a distinct identity and few others which are not addressed by ICAP but are described by BCA like Quasihomogenous. This study analysed four nuclear patterns with overlapping features, namely Homogenous, speckled, Dense Fine Speckled70(DFS70) and quasi-homogenous to identify challenges posed in their identification due to overlapping features.

Methods: All samples which were reported as positive for the above four nuclear patterns (n=388) by IIF using HEp-2 cell were included in the study. LIA was performed on 103 such samples to look for association between the ANA patterns and specific antibody detected by LIA.

Results: DFS70 pattern is a rare pattern and existed in combination with other autoantibodies thus making its identification difficult on IIF. Homogenous pattern corresponded to AC- 29 (anti-topoisomerase, anti-Scl 70) which was probably due to wrong identification. Mixed pattern i.e speckled and homogenous was associated with Sm and U1sn RNP antibodies.

Conclusions: DFS 70 is a pattern with overlapping features of both homogenous and speckled and calls for expertise reporting. More awareness is required about AC 29 pattern as it is an overlap of five different components. Its identification poses significant challenges and is rightly placed in the expert reporting by ICAP. Mixed pattern (speckled and homogenous) referred to as Quasihomogenous by BCA needs to be addressed by ICAP.

Background: Clinical testing for drugs of abuse typically involves initial screening followed by confirmatory testing. Due to limited evidence-based guidelines, the healthcare provider makes the decision to confirm abnormal screens based on the clinical context. This two-step approach proved to be inadequate in scenarios like maternal substance abuse and subsequent fetal/ newborn exposure. The goal of this study is to assess and improve the confirmatory testing rate of abnormal screens among pregnant patients at our women's center.

Methods: A retrospective chart review was conducted to assess the confirmation rates among positively screened pregnant patients, and a lab stewardship initiative was implemented to remind ordering physicians about the importance of confirmatory drug tests. Abnormal screens were classified as expected positives based on the medication-related interference, social history and self-reported substance use from the provider notes.

Results: Only 28% of pregnant patients with unexpected positive drug screens underwent confirmatory testing during the pre- intervention period, which rose significantly to 67% during the post-intervention period. Furthermore, outcome analysis revealed that 50% of patients with concordant confirmatory test results were referred to social work and psychiatry in the post-intervention period.

Conclusions: This study highlights the value of laboratory stewardship in optimizing drug testing practices for pregnant patients.

Introduction: Chronic Kidney Disease (CKD) is prevalent in Pakistan, necessitating accurate diagnostic methods. This study evaluates the CKD-EPI 2009, CKD-EPI 2021, CKD-EPI Pak, MDRD, and EKFC equations against creatinine clearance (CrCl) to determine their diagnostic accuracy for CKD in the Pakistani population.

Methods: n a retrospective cross-sectional study, data from 2,310 participants aged 18-70 were analyzed at The Aga Khan University in Karachi. Serum creatinine (SCr) and CrCl were recorded, and eGFR was calculated using five equations. Statistical analyses compared eGFR equations with CrCl, assessing sensitivity, specificity, and predictive values.

Results: EPI-Pak exhibited the highest sensitivity (95.15%) and agreement (94.85%) followed by EPI-2009 and EPI-2021 which showed the closest agreement with CrCl. Bland-Altman plots also indicated that EPI-Pak had the best agreement with CrCl.

Discussion: EPI-Pak outperformed other equations in estimating eGFR for the Pakistani population, aligning with previous recommendations for South Asians. EKFC, although highly specific, was less effective overall.

Conclusion: EPI-Pak is the most accurate equation for diagnosing CKD in the Pakistani population. Its clinical implementation could improve CKD diagnosis and patient outcomes. Future studies should further validate these findings with larger, diverse samples.

Follicular cystitis (FC) is a chronic form of cystitis with uncertain etiology, characterized by the presence of lymphoid follicles in the bladder mucosa as a result of chronic irritation. This can be caused by various factors such as prolonged catheterization, lithiasis, recurrent urinary tract infections or neoplastic bladder pathology. Although it is a rare pathology, it is mainly seen in women over 50 years of age and manifests with nonspecific urinary symptoms such as dysuria, pollakiuria, haematuria and suprapubic pain. We describe a case of a 12-year-old boy with dysuria, haematuria and hypogastric pain. Despite the absence of a history of lithiasis or trauma, and no bacteria found in urinalysis, erythrocytes and leukocytes were found, along with reactivated and degenerated urothelial cells accompanied by heterogeneous-sized cells with a high nucleus/cytoplasm ratio. Ultrasonography showed no abnormalities, but cystoscopy revealed irregularities in the trigone of the bladder and biopsy confirmed the presence of lymphoid follicles, characteristic of FC. This case underscores the relevance of considering FC in patients with persistent bladder irritation and recurrent haematuria. Cystoscopy and histologic evaluation are crucial for an accurate diagnosis, although the role of the clinical laboratory is limited, an experienced specialist can facilitate a proper diagnosis.

The Clinical Laboratory (CL) is involved in the prevention, diagnosis and follow-up of disease, as well as in the monitoring of treatment. For this reason, the CL must have robust quality systems in place in order to provide reliable results that help to ensure correct health care. Since the entry into force of the European regulation (IVDR) on in vitro diagnostic medical devices (EU) 2017/746 has generated the loss of CE marking in some laboratory determinations. In our case, Krebs von den Lungen-6 (KL-6), a diagnostic, severity and prognostic marker, as well as a marker of response to treatment, currently has the RUO (research use only) marking and, given its importance in our healthcare environment, we have validated the method with the new reagent in order to be able to continue with the clinical care of patients. In addition, this would keep this analyte within the scope of accreditation. Following the specific CLSI protocols, we carried out a study of precision, linearity as well as the limit of blank and the limit of detection, obtaining results within the limits established by the laboratory. This positive validation of KL6 allows us to continue using this analyte for clinical use and within the scope of accreditation.

Introduction: Assessing LDL cholesterol is pivotal for cardiovascular risk evaluation. While direct LDL measurement is accurate, calculated LDL methods offer practicality and cost-effectiveness. This study aims to evaluate the correlation between direct LDL measurement and various calculated LDL methods, shedding light on their clinical utility.

Methods: A retrospective analysis of lipid profiles from 1075 patients was conducted, encompassing direct LDL measurement and calculation of LDL using nine different methods. Statistical analyses, including correlation coefficients and scatter plots, were employed to assess the agreement between direct LDL and calculated LDL methods.

Results: Surprisingly, all calculated LDL methods exhibited a robust correlation with direct LDL measurement across the study cohort. The Friedewald equation, as well as modified equations demonstrated particularly robust correlations. These findings indicate the reliability of calculated LDL methods in estimating LDL cholesterol levels.

Discussion: The significant correlation observed between direct LDL measurement and calculated LDL methods underscores the clinical utility of the latter. While direct LDL measurement remains the gold standard, calculated LDL methods offer practical advantages, particularly in resource-limited settings.

Conclusion: In conclusion, this study highlights the excellent correlation between direct LDL measurement and calculated LDL methods in lipid profile assessment. Clinicians can leverage calculated LDL methods as reliable alternatives for LDL cholesterol estimation, facilitating efficient cardiovascular risk evaluation in routine clinical practice. Further research may explore the optimal use of calculated LDL methods in specific patient populations, enhancing their clinical applicability and utility.

Background: Familial hypocalciuric hypercalcemia (FHH) is a rare, benign condition that shares characteristics with primary hyperparathyroidism (PHPT), a more sinister condition that requires surgical intervention. This case report demonstrates misdiagnosis of FHH and highlights important learning points to prevent this in the future.

Case presentation: Hypercalcaemia was incidentally discovered in a 21-year-old patient who had no symptoms of hypercalcaemia and no significant family history. Clinical examination was normal. Biochemical investigations revealed hypercalcaemia of 2.84mmol/L (2.15 - 2.50mmol/L) and hypophosphataemia of 0.71mmol/L (0.78 - 1.42mmol/L). Parathyroid hormone (PTH) concentration was mildly and inappropriately elevated (10.3pmol/L [2.0 - 8.5pmol/L]) triggering a suspicion of PTH-mediated hypercalcaemia. Parathyroid scintigraphy reported an ill-defined area of focal uptake above the left thyroid lobe. Fractional excretion of calcium estimations on 24hour urine collections were borderline (0.01) for FHH on multiple occasions however, further investigations to exclude FHH were not performed before a diagnosis of primary hyperparathyroidism was made, and a total parathyroidectomy performed. Several months post-operatively, the patient still demonstrated persistent hypercalcaemia. Her siblings had since been diagnosed with FHH. The patient was then retrospectively diagnosed with FHH. Genetic testing for FHH is not available in South Africa which limited the opportunity to confirm the diagnosis.

Conclusions: This case report provides a classical presentation of the rare, benign disorder of FHH. It highlights the negative outcomes that may result from misdiagnosis of this condition as PHPT. Biochemical investigations play an integral role in differentiating these conditions. Effective clinician-laboratory communication is crucial for optimal patient outcomes.

A narrative review of the main guidelines and recommendations published from 2011 up to date about the status of vitamin D deficiency has been carried out. The objective of this review is to discuss the origin of the controversy about the status of this entity, as well as the evolution of the methodological aspects and clinical situations that require vitamin D screening. The results obtained indicate that the criteria defining vitamin D status, according to two studies published in 2011, the Institute of Medicine (IOM) recommendations and the Endocrine Society (ES) guidelines, regardless the affected population. Concerning the methodology used, progress has been made thanks to the Vitamin D Standardization Program (VDSP), although the most recent results from the external Vitamin D External Quality Program Assessment Scheme (DEQAS) indicate that there is still a significant bias among the different immunoassays available. In relation to the criteria for screening, an agreement is observed in the most recent publications.

Introduction: The standardization of reporting in clinical laboratories, particularly regarding Serum Protein Electrophoresis (SPEP) and Urine Protein Electrophoresis (UPEP), is crucial for effective communication of findings to clinicians and optimal patient management. However, in countries like Pakistan with limited healthcare resources and a prevalent self-payment model, challenges arise in achieving standardized reporting practices. This manuscript addresses the need for standardized guidelines for protein electrophoresis reporting in Pakistan, aiming to enhance laboratory practices and patient care.

Methods: This study was conducted at the Aga Khan University Hospital (AKUH), Pakistan. A team consisting of five Consultant Chemical Pathologists and two senior technologists, led by the Section Head of Chemical Pathology at AKU, used a Modified Delphi Methodology to achieve consensus on the developed framework. Consensus was defined as agreement by at least six out of the seven experts (85.71%). The source guideline for this process was the Recommendations for Standardized Reporting of Protein Electrophoresis from Australia and New Zealand.

Results: Consultant Chemical Pathologists reviewed the original and modified recommendations, resulting in a framework of ten sub-sections and 65 recommendations. Through a series of four meetings, including a diverse team of experts, the recommendations were systematically critiqued and reviewed. After detailed deliberations, 54 recommendations were finalized by consensus. The final document was further reviewed by CCBP staff and additional consultants from different institutions in Pakistan to ensure unbiased and comprehensive expert input.

Discussion: The developed guidelines offer a framework for consistent and comprehensive reporting of PEP results, addressing variations in practices among clinical laboratories in Pakistan. Key modifications to the recommendations reflect a pragmatic approach to navigating resource constraints, ensuring that laboratory reports remain informative and actionable for clinicians. By prioritizing clinical relevance and practicality, the guidelines aim to enhance diagnostic accuracy and facilitate appropriate clinical management decisions.

Conclusion: The standardized reporting guidelines for SPEP and UPEP represent a significant milestone in optimizing laboratory practices and improving patient care in Pakistan. Moving forward, continued monitoring and adaptation of the guidelines will be essential to ensure their sustained relevance and effectiveness in meeting the evolving needs of the healthcare system. Embracing a commitment to excellence in laboratory practices holds promise for advancing healthcare quality and accessibility in low-resource settings globally.

Background: Serum (plasma) creatinine and cystatin C are widely used in pediatric clinical practice to assess glomerular filtration rate. Both markers have limitations due to the low index of individuality, which affects the clinical sensitivity of population-based reference intervals, especially when wide age ranges are considered. This study aimed to establish age-related reference intervals for plasma cystatin C and creatinine in Vietnamese children.

Methods: A total of 454 children, equally divided between boys and girls, aged from 1 day to 18 years, were recruited from the outpatient clinic of Vietnam National Children's Hospital. None of the participants had kidney or infectious diseases. Plasma samples were analyzed for cystatin C and creatinine using standard clinical chemistry methods. Using the the Lambda-Mu-Sigma method, we derived centile charts showing dynamic changes in these biomarkers.

Results: In this cohort, plasma creatinine levels were high at birth, declined to their lowest point between ages of 2 and 3 years, and then gradually increased until adulthood. Plasma cystatin C levels were also elevated at birth, decreased to a steady state around age of 2 year, and remained stable until age of 10 years. From ages 10 to 14 years, cystatin C levels slightly increased, followed by a decrease from ages 15 to 18 years.

Conclusions: Accurate assessment of glomerular filtration in children requires reliable laboratory tests and age-specific reference intervals. Providing serum (plasma) cystatin C and creatinine reference intervals with appropriate age partitions is crucial for improving the clinical sensitivity for detecting renal dysfunction, especially during the first few years of life.