Biological variability of the most common biochemical parameters

The results of laboratory tests are analyzed against reference values that are determined in a population of healthy people prepared for the test in accordance with the relevant guidelines. Such a reference system works perfectly when analyzing the results of tests of patients from whom the material for determinations was collected in similar conditions. To better match the reference values ranges are stratified, most often by gender, age, or race of the patient – the most common and the most significant biological variability. The values of the measured parameter are also influenced by within-subject biological variability to e.g. the time of the day, food consumption, or physical exercise. This variability influences the results of random testing, often performed in patients with emergencies. The measure of both of these variations is the index of individuality, i.e. the ratio of within-subject biological variability to between-subject biological variability. In the present work, the factors influencing the circadian, seasonal, and between-subject biological variations of the selected clinical chemistry parameters are presented. Knowledge about these variations is important for the physician and the supporting laboratory diagnostician, particularly helpful in the analysis of pathological or inconsistent with the clinicians' expectations results to distinguish results related to the disease from results related to biological variability.

Circulating miRNAs as potential biomarkers in assessing the risk of cardiac arrhythmia, its recurrence, or the effectiveness of antiarrhythmic therapy

Cardiac arrhythmias belong to a group of diseases that, in some cases, can be life and health threatening. The most common arrhythmia is atrial fibrillation, while the most dangerous dysrhythmia is ventricular fibrillation. The list of factors determining and influencing the occurrence and course of abnormal heart rhythms, and thus determining the fate of the patient, is very diverse. The priority in the fight against arrhythmia is the short time to detect and diagnose and identify patients with a high probability of recurrent forms of particular arrhythmias. In recent years, scientists' attention has focused on circulating microRNAs, which have a high potential to act as biomarkers of cardiac arrhythmias. miRNAs are short, single-stranded ribonucleic acid molecules with a length of about 22 nucleotides. MicroRNAs intracellularly play the role of regulators of gene expression, while extracellularly they are mediators of intercellular communication. MiRNAs are characterized by high tissue and organ specificity. In addition, even minimal quantitative changes affect the homeostasis of the body and initiate a pathological state, which suggests the possibility of using them to identify abnormalities, e.g., in the structure and functioning of the heart. The conclusions of scientists obtained so far from a large number of scientific sources and confirmed studies are not unequivocal, however, they indicate the relationship of circulating miRNAs with the occurrence of specific arrhythmia and give hope for the practical use of microRNA as biomarkers in laboratory diagnostics.

Detection of oligoclonal bands as a part of the diagnosis of multiple sclerosis – case studies

Introduction: Oligoclonal bands are the result of the synthesis of antibodies of limited heterogeneity, that is, directed against one or more specific antigens. Their detection is an important element in the diagnosis of autoimmune diseases. In multiple sclerosis, the diagnostic sensitivity of the determination of oligoclonal bands is high. Aim: The aim of this study is to answer the question whether the detection of oligoclonal bands a more valuable study is than the Tibbling-Link index and reibergram analysis in the context of the diagnosis of multiple sclerosis. Material and methods: Oligoclonal bands were tested in the cerebrospinal fluid and serum from 9 patients suspected of multiple sclerosis using the Sebia HYDRAGEL 3 CSF ISOFOCUSING kit. Results: In 7 out of 9 patients the Tibbling-Link index, reibergram analysis and oligoclonal bands detection clearly indicated intrathecal IgG synthesis. In 2 of 9 patients, detection of oligoclonal bands indicated intrathecal IgG synthesis and the value of Tibbling-Link index and reibergram analysis did not indicated intrathecal IgG production or these tests indicated limit values. Conclusions: The detection of oligoclonal bands in many cases allows for faster diagnosis and introduction of therapy. This test should be an integral part of SM diagnostics.

2021 PoLA/CFPiP/PCS/PSLD/PSD/PSH guidelines on the diagnosis and therapy of lipid disorders in Poland

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Bilirubin monitoring – future prospects

Monitoring of bilirubin concentration is essential during early neonatal life. According to the American Academy of Pediatrics Clinical Practice Guideline, the total serum bilirubin or transcutaneous bilirubin level should be measured in each infant in the first 24 hours of life. The concentration of bilirubin has been measured for 150 years. During that time the analytical methods for its determination have been significantly improved, the nomenclature of bilirubin has been also unified, but it is still unknown what concentration of bilirubin cause a life-threatening encephalopathy in the newborn. Under the current recommendations, clinical decisions to introduce phototherapy in the treatment of newborns’ hyperbilirubinemia are based on total bilirubin concentration, which is determined on biochemical analyzers and point of care testing systems. However, it is not always possible to predict encephalopathy based on the total bilirubin level. Probably in the future, as the availability of routine methods for the determination of unconjugated, free bilirubin becomes more available, measurement of “free” bilirubin will improve risk assessment for bilirubin neurotoxicity.

Microorganism idenitfication – stability and correctness of mass spectrometry method (MALDI TOF MS)

Introduction: MALDI TOF MS method is increasingly used in routine microbiological diagnostics to identify clinical strains. The result of the identification test is based on the measurement of the mass, charge and flight time of the protein ions. This makes it possible to monitor and supervise the method using a numerical score developed with statistical techniques. Aim: The study aimed to determine the stability and correctness of the mass spectrometry method. Materials and methods: To evaluate the characteristics of the method, microbial identification tests were performed using reference strains. All tests were performed as part of the MALDI TOF MS internal quality control system. Results: All reference strains (100%) were correctly identified to the species level, although the score values were not always within the reliability criteria of the results established by the producer. It was found that the mean values of the score were from 2.000 – 2.299 (49.2%) and 2.300 – 3.000 (50.0%). The coefficient of variation for control tests performed in the consecutive years ranged from 5.18 – 6.56%, which evidence of the high stability of the method. For individual species, reproducibility precision over the 8 years ranged from 2.89% (n = 13) for Enterococcus faecalis ATCC 51299 to 7.02% (n = 28) for Klebsiella pneumoniae ATCC 700603, which proves the high precision of measurements. Conclusions: The mass spectrometry method is characterized by very high stability and correctness. The intra-laboratory quality control system using reference strains is a useful tool for monitoring and supervising the method and laboratory personnel competency performing identification tests during routine microbiological work.

Amyloidoses – pathogenesis, classification, diagnosis

Amyloidoses – also known as amyloidosis or betafibrillosis – a diverse group of diseases in which amorphous protein with a changed conformational structure is deposited extracellularly, leading to the failure of many organs. The basic classifications of amyloidoses take into account: the type of precursor protein, the division into generalized (systemic) amyloidoses, in which amyloid deposits accumulate in many organs, vessel walls and connective tissue (e.g. AL amyloidosis) and local (localized) amyloidoses – limited to only one organ (e.g. corneal amyloidosis) as well as congenital and acquired diseases. Symptoms of amyloidosis are non-specific and not very characteristic, moreover, their severity depends on the type of disease and organ involvement. The diagnosis of amyloidosis should be considered in patients with heart failure without coronary artery disease, with neuropathy, or proteinuria or hepatomegaly of unclear origin. Diagnosis of amyloidosis is based on the evaluation of tissue biopsy samples and the presence of abnormal proteins, i.e. amyloid, or on the fibrillary evaluation confirmation of the filamentous nature of amyloid deposits using electron microscopy. The next step is differential diagnosis and amyloid differential identification, which is based on immunohistochemical and immunofluorescence studies using labeled antibodies. The "gold standard" used in typing amyloidosis and identifying an amyloidogenic protein is mass spectrometry. Laboratory tests are used to assess organ involvement, which is the basis of the prognostic classification.

Post-transfusion purpura due to anti HPA–1a antibodies – a retrospective case report

Post-transfusion purpura is a life-threatening adverse reaction associated with a reduction in platelet counts below 10 x 109/L and bleeding. It usually occurs in women who, due to their pregnancies, have developed antibodies directed against human platelet antigen (HPA), most often anti-HPA 1a. The case described by us concerned an 83-year-old woman who received two units of red blood cells (RBC) due to severe secondary anemia. Seven days after the transfusion, she developed skin symptoms of thrombocytopenic diathesis, gastrointestinal bleeding, and a reduced number of platelets (3 x 109/L), and the patient’s serum (genotype HPA-1b/1b) was positive for anti-platelet antibodies with HPA-1a specificity and directed against human leukocyte antigen (HLA) class I and class II antibodies, unresponsive to the lymphocytotoxic test. Prompt diagnosis by our transfusion medicine consultant and the initiation of treatment with intravenous immunoglobulins certainly shortened the duration of thrombocytopenia and bleeding, and possibly also saved the patient’s life.

Morphological and biochemical evaluation of blood in young women with common acne – preliminary report

Introduction: Acne is one of the most common skin diseases, defined as a chronic, inflammatory disease of the sebaceous gland and hair follicle. It is most common in young people, although the lesions may persist even up to 30 – 40 years of age. It is characterized clinically by the presence of non-inflammatory and inflammatory eruptions (papules and pustules) and usually with increased production of sebum. The reasons for the appearance of acne include hormonal disorders, obesity, stress, diet, environmental and genetic factors, cosmetic substances, and medications. Patients with acne exhibit an overreaction of the immune system and an excessively intense inflammatory response. The aim of the study is to evaluate selected biochemical and blood count parameters in young women with acne vulgaris. Material and methods: The study was conducted on 20 students of the Academy of Physical Education, aged 20 – 26, including 10 women with mild acne vulgaris and 10 women without acne symptoms. All women underwent complete blood counts (CBC) with the division of leukocytes into subpopulations (5 DIFF) and biochemical tests in blood serum (lipid profile, liver function tests, concentration of total protein and its electrophoretic fractions, CRP). Results: There were no statistically significant differences in the group of women with acne compared to the control group in terms of the assessed serum biochemical parameters. Women with mild acne vulgaris had a significantly lower number of erythrocytes, higher MCV, and a lower percentage of monocytes, with no significant differences in other blood count parameters. The percentage of neutrophils tended to be higher in the group of women with acne vulgaris. Conclusions: 1. Inflammation accompanying mild acne vulgaris may change the number of monocytes and neutrophils in blood counts. 2. The lower number of red blood cells in women with symptoms of acne vulgaris may be the result of chronic inflammation.

A case study of a patient with anti-Yta alloantibodies against the high-prevalence antigen of red blood cells qualified for heart transplantation

The Yta antigen from the Cartwright blood group system is a high-prevalence antigen found in 99.8% of the population. The literature data shows that antibodies anti-Yta demonstrate the variable clinical significance and are rarely the cause of a hemolytic post-transfusion reaction. The study aims to present the difficulties related to the selection and sustainable supply of blood for transfusion for the patient of the Silesian Centre for Heart Diseases with anti-Yta alloantibodies, qualified for a heart transplant. If Yt(a-) blood is not available Institute of Hematology and Transfusion Medicine in Warsaw, referring to reports in the publications, allowed transfusion of the least incompatible red blood cells in indirect antiglobulin test. One hour after transfusion of leucocyte-depleted concentrate of red blood cells (RBCs), issued in accordance with the above recommendations by Regional Blood Donation Center in Katowice as the least incompatible, the patient was observed to experience symptoms of an adverse post-transfusion reaction. For subsequent transfusions, RBCs from Yt(a-) donors were selected, of which only eight were registered in Poland at that time. Medical decisions on RBCs transfusion in patients for whom no compatible blood can be selected is very difficult, and the benefits of incompatible transfusion should be weighed against the risk of possible complications. To avoid this, it should be remembered that the early identification of antibodies increases the chance of finding serologically compatible blood and in many cases allows to supply blood for a patient with autologous donations.