Diagnostic validation of two SARS-CoV-2 immunochromatographic tests in Slovenian and Croatian hospitals.

AIM: To diagnostically validate two point-of-care (POC) rapid antigen tests for SARS-CoV-2 by comparing their results with those of laboratory-based real-time polymerase chain reaction tests (RT-PCR). METHODS: The study enrolled 455 patients from two Slovenian and two Croatian hospitals. The NADAL COVID-19 Ag Test (Nal von Minden, Moers, Germany) and ALLTEST COVID-19 Antigen Test (Hangzhou ALLTEST Biotech Co., Ltd, Hangzhou, China) were diagnostically validated in emergency care departments of two Slovenian hospitals, while only ALLTEST COVID-19 Antigen Test was validated in two Croatian hospitals. RESULTS: The antigen test results were in very good agreement with the RT-PCR results (Cohen's Kappa between 0.747 and 0.891 for the NADAL COVID-19 and between 0.820 and 0.954 for the ALLTEST COVID-19). The NADAL COVID-19 Ag Test had the sensitivity between 66.67% and 92.31%, with a negative predictive value between 85.51% and 99.2%. The ALLTEST COVID-19 Antigen Test had the sensitivity between 81.39% and 91.11%, with a negative predictive value between 85.45% and 98.78%. CONCLUSION: The antigen tests are practical and reliable screening assays for SARS CoV-2 in emergency care departments. Both antigen tests can be used as screening tests to reduce the number of patients waiting for RT-PCR results. Even more, they can be used to quickly isolate COVID-19 patients and reduce hospital transmissions.

CLSI-based verification and de novo establishment of reference intervals for common biochemical assays in Croatian newborns.

Introduction: This study aimed to examine whether the Canadian Laboratory Initiative on Pediatric Reference Intervals (CALIPER) reference intervals for 19 commonly used biochemical assays (potassium, sodium, chloride, calcium, magnesium, inorganic phosphorous, glucose, urea, creatinine, direct and total bilirubin, C-reactive protein (CRP), total protein, albumin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyl transferase (GGT), alkaline phosphatase (ALP) and lactate dehydrogenase (LD)) could be applied to the newborn population of one Croatian clinical hospital. Materials and methods: Reference interval verification was performed according to the CLSI EP28-A3c guidelines. Samples of healthy newborns were selected using the direct a posteriori sampling method and analyzed on the Beckman Coulter AU680 biochemical analyzer. If verification wasn't satisfactory, further procedure included de novo determination of own reference intervals by analyzing 120 samples of healthy newborns. Results: After the first set of measurements, 14/19 tested reference intervals were adopted for use: calcium, inorganic phosphorous, glucose, urea, creatinine, total bilirubin, CRP, total protein, albumin, AST, ALT, GGT, ALP and LD. A second set of samples was tested for 5 analytes: potassium, sodium, chloride, magnesium and direct bilirubin. The verification results of the additional samples for sodium and chloride were satisfactory, while the results for potassium, magnesium and direct bilirubin remained unsatisfactory and new reference intervals were determined. Conclusions: The CALIPER reference intervals can be implemented into routine laboratory and clinical practice for the tested newborn population for most of the analyzed assays, while own reference intervals for potassium, magnesium and direct bilirubin have been determined.

Laboratory professionals' attitudes towards ISO 15189:2012 accreditation: an anonymous survey of three Croatian accredited medical laboratories.

INTRODUCTION: Effective implementation and continual compliance with ISO 15189:2012 require ongoing commitment and active involvement of laboratory staff. Our aim was to assess attitudes regarding accreditation implementation by conducting a survey in three Croatian accredited medical laboratories. MATERIALS AND METHODS: An anonymous survey consisting of 34 questions was distributed either electronically or in a paper form a week prior to scheduled annual audits. Distributions of answers regarding age, work experience, laboratory workplace, and education level and according to the respective laboratory were compared. RESULTS: The overall response rate was 76% (225/297). Preference towards working in an accredited laboratory and a positive attitude were revealed by 70% and 56% participants, respectively, with better process documentation as the main advantage. Only 14% of responders considered themselves completely familiar with ISO 15189:2012. Total of 68% of responders felt that accreditation increases the usual workload, with excessive paperwork as the main contributor. Half of the responders declared partial agreement that accreditation requirements and expectations were clearly explained and claimed that their suggestions were taken into account only occasionally, which was especially emphasized by technical staff. The vast majority (89%) completely follow the prescribed protocols. Only 27% consider turnaround time monitoring useful. Competence assessment is considered efficient by 41% of responders. The majority (73%) prefer an online audit in times of COVID-19. CONCLUSIONS: Despite an overall positive attitude towards accreditation, further efforts are needed in providing better education about ISO 15189:2012 for technical staff and modifying formats of competence assessment, in order to achieve better adherence to ISO 15189:2012 requirements.

Accreditation of medical laboratories in Croatia--experiences of the Institute of Clinical Chemistry, University Hospital "Merkur", Zagreb.

Since 2003 when the international norm for implementation of quality management in medical laboratories (EN ISO 15189, Medical laboratories--Particular requirements for quality and competence) was established and accepted, accreditation has become practical, generally accepted method of quality management and confirmation of technical competence of medical laboratories in the whole world. This norm has been translated into Croatian and accepted by the Croatian Institute for Norms as Croatian norm. Accreditation is carried out on voluntary basis by the Croatian Accreditation Agency that has up to now accredited two clinical medical biochemical laboratories in the Republic of Croatia. Advantages of accredited laboratory lie in its documented management system, constant improvement and training, reliability of test results, establishing users' trust in laboratory services, test results comparability and interlaboratory (international) test results acceptance by adopting the concept of metrological traceability in laboratory medicine.

[Single cell--definitive diagnosis! Where the profession ends and the art begins?]. / Jedna stanica--konacna dijagnoza! Gdje prestaje struka i pocinje umjetnost?

Cell is a morphologically and functionally the tiniest living organism, present from the very beginning of life on the Earth. Specialized cell types make up specific tissues and organs of the human body. Cell itself and cell elements are liable to morphological, functional, phenotypic and genotypic alterations in various physiological and pathological states. These alterations are studied by cytodiagnosis to diagnose the disease at cellular level. Cytologic examinations belong to the group of morphological, non-aggressive or minimally invasive tests that are easy to perform for both the patient and the professional. In addition, these tests are highly reliable and preferred to the related diagnostic procedures for providing immediate orientation and definitive diagnosis, thus saving both time and money. With the introduction of adjunctive technologies such as cell-surface marker analysis, computer image analysis, molecular and cytogenetic technologies performed on cytologic smears, cytology has become an ever more important factor in the diagnosis, subtyping and prognosis of malignant tumors. Thorough knowledge of cell morphology is a basis for proper performance and understanding of cytology techniques. A cytologist needs to be familiar with clinical manifestations of the disease and to be informed on all relevant data on the patient and his current and previous medical history, in order to be able to issue findings that are understandable and usable to all clinicians and patients. It requires close collaboration between the cytology laboratory and the ward, and among the cytologist, the patient and the clinician. Good collaboration with other diagnostic professions such as pathology, laboratory, molecular and cytogenetic diagnosis is by no means less important. Cytology as a profession implies knowledge of the morphological characteristics of normal cells and cells in various physiologic states, along with due knowledge of the morphology, phenotypic and genetic features of pathologic alterations. However, synchronizing and combining cytologic morphology with other sophisticated diagnostic procedures to reach an accurate diagnosis, subtyping and prognosis of tumor disease is artistry indeed.

Fine-needle aspiration cytology yield as a basis for morphological, molecular, and cytogenetic diagnosis in alk-positive anaplastic large cell lymphoma with atypical clinical presentation.

ALK positive anaplastic large cell lymphoma is a T-cell lymphoma usually occurring in children and young adults. It frequently involves lymph nodes and extranodal sites and is associated with favorable prognosis. A 20-year old man was admitted for painful mass in the left axilla with overlying skin redness. Clinical presentation and US findings were highly suspicious for sarcoma. Definitive diagnosis was established cytolologically and using ancillary technologies from cytological samples. Fine needle aspiration cytology of tumor mass (lymph node conglomerate and surrounding tissue) show predominance of large, pleomorphic, atypical cells with large nuclei and vacuolised cytoplasm. Atypical cells immunocytochemically were positive for LCA, CD30, CD3, EMA, and ALK; negative for CD15 and CD56. NPM-ALK transcript was detected by reverse transcriptase-polymerase chain reaction (RT-PCT). Molecular analysis of TCRß and TCRγ genes demonstrated clonal TCR genes rearrangement. Complex karyotype with multiple numerical and structural changes was found on conventional cytogenetics. These findings excluded sarcoma and corroborated the diagnosis of ALK positive ALCL. Cutaneous involvement in ALCL can clinically mimic sarcoma, especially in cases with localized disease without B symptoms. In those cases, immunostaining, PCR, and conventional cytogenetics are helpful to exclude sarcoma. Diagn. Cytopathol. 2017;45:51-54. © 2016 Wiley Periodicals, Inc.

Follicular and mantle cell lymphoma characteristics present simultaneously in the same lymph node.

Follicular lymphoma is composed of clonal germinal center B cells. It shows a follicular pattern lacking mantle zones, with a network of interfollicular dendritic cells. Transformation to more aggressive lymphomas is documented, but the only connections to mantle cell lymphoma are described cases of composite lymphoma consisting of these 2 entities. We discuss here a case of a lymph node harboring CD20, CD10, BCL2, BCL6, cyclin D1, CD5, Ki67, and SOX11 with CD21, showing an almost intact network of dendritic cells in one part of a lymph node, and CD20, CD5, SOX11, BCL6, cyclin D1, CD10, Ki67, and CD21 cells restricted to the mantle area in another part of the same lymph node. Both parts of the lymph node had BCL2 rearrangement, a lack of t(11:14)(q13;q32), the presence of SOX11 expression, and the same clonal band. The described case suggests heterogenous development of small cell lymphomas and indicates the possibility of differentiation regression.

Immunohistochemical analysis of ZAP-70 expression in chronic lymphocytic leukemia.

This paper shows a protocol for the detection of ZAP-70 expression in B-CLL (B cell chronic lymphocytic leukemia) tumor cells by common immunohistochemical methods. The study was conducted on bone marrow trephine biopsies from 62 B-CLL patients at the time of diagnosis. Immunohistochemical reactions based on peroxidase and alkaline phosphatase reactions were used, as well as double immunofluorescent labeling for ZAP-70 detection as an indirect marker of mutated and unmutated CLL. Clinical relevance of the ZAP-70 expression detection method was assessed using chi2 test between ZAP-70 positivity data and other known prognostic factors, i.e., clinical and cytogenetics data. ZAP-70 was detected in 13 out of 62 patients. Statistically significant results were obtained for ZAP-70 positive cases and known indicators of worse prognosis. Immunohistochemical analysis supported by double immunofluorescent labeling, as shown here, is an easy and reliable technique for the detection of ZAP-70 expression in B-CLL tumor cells applicable in every hematopathology laboratory.

FOXP1 and BCL2 show similar immunoenzymatic pattern in bone marrow trephines of chronic lymphocytic leukemia patients.

Indolent B lymphoproliferative disorder, chronic lymphocytic leukemia (CLL) represents one of the most common hematologic diseases in the Western world. Although there are many disease development markers known so far, for example, B-cell lymphoma/leukemia (BCL) 2, new ones are needed for better understanding course of the disease. FOXP1 is known to be strongly expressed after B-cell activation. Its essential role in B-cell development suggested that it could also have a role in a various tumor B-cells. We have analyzed 74 bone marrow samples from B-CLL patients for presence of FOXP1 and its gene aberrations in tumor cells. Our results showed presence of FOXP1 protein mostly in the same tumor cells as BCL2 protein, and their specific immunostaining pattern. Diffuse immunostaining pattern of both proteins is present in patients with higher clinical stages of B-CLL and with some other markers that indicate worse outcome of the disease. Thus, FOXP1 and/or BCL2 immunostaining of bone marrow trephine sections could serve as an immunohistochemical marker in B-CLL.