Revista del Laboratorio Clínico最新文献

Leptomeningeal involvement in multiple myeloma is a rare and serious complication that usually occurs after relapses of the disease. To establish a correct diagnosis, it is necessary to demonstrate, by cytology, the presence of clonal plasma cells in the cerebrospinal fluid.

The clinical laboratory detected this complication in a patient diagnosed with refractory multiple myeloma after analysing a cerebrospinal fluid sample. The patient suffered from several neurological symptoms, such as faecal incontinence and lower limb mobility limitation. Pleocytosis and proteinorachia was initially observed, along with high levels of high-fluorescence cells, which are sometimes associated with malignant cells. The protein electrophoresis and immunofixation of the cerebrospinal fluid confirmed the presence of the monoclonal component, already detected in blood. After processing the sample by flow cytometry it was confirmed that there was infiltration of malignant plasma cells in the central nervous system.

This laboratory played a central and essential role in the diagnosis of this uncommon complication, by the combined use of protein electrophoresis, immunofixation, flow cytometry, and the haematology autoanalyser. This latter included the high fluorescence cells as a promising biomarker in the screening for the presence of tumour cells in biological fluids.

Iron is an essential chemical element for all living organisms, and is required for a broad spectrum of vital metabolic functions. The study of iron metabolism can be challenging in some situations, such as in patients with chronic diseases, due to the effect of inflammation response. In recent years, clinical laboratory research has introduced new biomarkers to those commonly used, with the aim of improving the diagnosis and management of iron deficiency. In this work, a systematic search of the scientific evidence reported during the last decade has been made for the following biomarkers: morphological diagnosis of peripheral blood, hematimetric indices, and plasma concentrations of transferrin (and its indices), ferritin, transferrin receptor, and haemoglobin, in iron deficiency. Recommendations are made for these biomarkers related to the diagnosis and management of the iron-deficient patient.

The second in the series of the Committee of Andrology and Techniques of Assisted Reproduction Committee, is prepared in order to carry out the correct maintenance, control and adjustment of the equipment used in the Andrology and Embryology laboratory. It focuses on the auxiliary equipment that supports the different processes of assisted reproduction. It includes a control program for monitoring and measuring equipment with revision frequencies and acceptance criteria.

The quality assurance of the pre-analytical phase is oriented towards two key aspects; the management of pre-analytical errors from the perspective of patient safety, and the improvement and harmonisation of procedures, based on the application of regulations and professional recommendations. Like the rest of the phases, it should include an internal quality assurance program, as well as the participation in external quality assurance programs.

The internal quality control should mainly be based on the identification of risks, systematic detection of errors, and establishment of indicators. The selection of indicators prioritising the impact on the patient, the way to detect and record errors in a systematic and easily exploitable manner, and also the variables used in the calculations, are important aspects to measure the effectiveness of improvement actions and to allow comparability between laboratories. In this sense, the external quality assurance programs of the pre-analytical phase based on the comparison of indicators are a useful tool for the design and implementation of a quality assurance program.

This document is intended as a support for each laboratory to select, implement, and evaluate its own indicators, according to the individual characteristics of its pre-analytical procedures, but without losing sight of the harmonisation between laboratories.

Dyslipidaemias are alterations in lipid metabolism that involve an excess, as well as a deficit, in lipid concentrations. These alterations are strongly associated with atherosclerosis, and it has been shown that its control reduces the incidence of episodes of ischaemic origin. Diagnosing dyslipidaemias from an aetiological point of view is very important, since the cardiovascular risk to which each one predisposes is different, and depends on the type of lipoprotein that is altered and its concentration. For this reason, it is very useful to have simple diagnostic algorithms that include the measurements of lipid metabolism that are available in most clinical laboratories in order to make the initial diagnosis of the type of dyslipidaemia. In the case of having the right diagnostic tools, identify it; and if not, to have the appropriate information to recommend the extension of the study in another centre with resources to establish the diagnosis

Mixed gonadal dysgenesis is a group of rare disorders of sexual differentiation and is a major cause of infertility. They show a mosaic karyotype 45,X/46,XY and can give rise to a great variety of phenotypes, finding from different degrees of sexual ambiguity in newborns, up to normal male phenotypes, normal female phenotypes or Turner syndrome (TS) phenotypes.

The case is presented of a patient diagnosed with TS from puberty and in whom the presence of fragments of Y chromosome was not detected. Given that patients with a diagnosis of TS with Y chromosome expression (full or partial) are at increased risk of developing gonadoblastoma, it is important to emphasise the importance of diagnosing the presence of the Y chromosome, and even recommending systematically performing techniques that increase the sensitivity in order to detect it, even though it has not been detected in the karyotype.

Introduction

Chromosome 8 trisomy, known as Warkany syndrome, is a rare genetic disease that has a very variable phenotype. Its main clinical characteristic is intellectual disability, dysmorphic facies, and deep plantar folds. The case is presented of a 10-year-old patient with gargoyle-like facies, mental retardation, and joint stiffness. The initial study of the karyotype, in which 20 metaphases were analysed, was normal. A single nucleotide polymorphisms (SNPs) array was requested from the laboratory.

Results

A complete gain of chromosome 8 was detected, which was interpreted as a mosaic trisomy 8 of approximately 20%, and which was compatible with the clinical presentation of the patient.

Discussion

This case shows the limitations of the analysis of only 20 metaphases in the karyotype in patients with mosaic aneuploidies. In these cases it would be recommended to extend the study to at least 30 metaphases in order to detect mosaicisms in low proportion.

Latex allergy is an altered response of the body on contact with proteins found in natural rubber latex. The symptoms of allergic hypersensitivity to latex are quite similar to those of food allergy, with the gastrointestinal symptoms being less frequent and the cutaneous ones being more typical after the use of latex and nasal gloves and / or the asthma after the inhalation of the dust from latex gloves or balloons.

In the case of very sensitive patients it can cause severe allergic reactions if it comes in contact with mucous membranes or internal cavities. There is a paradox that the hospital environment is the most risky place, given the existing amount of latex in direct and indirect use.

People who are allergic to latex often have cross-allergic reactions, sometimes severe, after eating certain fruits and vegetables. The cross-reactions are due to the common allergens present in latex and in different foods.

It is important to use molecular allergen analysis to detect false latex diagnoses due to problems of cross-reactivity with fruit proteins. It is indicated how these new tests have replaced less accurate and efficient analyses, achieving a considerable saving of resources.