A large number of existing diseases, an individual degree of manifestation of symptoms in different people complicate the diagnostic process. Often in practice it is not enough to use only the knowledge and skills of a doctor. In this case, a clinical diagnosis helps to make the correct diagnosis. With its help, pathologies are detected at an early stage, the development of the disease is monitored, its possible course is evaluated, and the effectiveness of the prescribed treatment is determined. Today, medical laboratory diagnostics is one of the fastest growing areas of medicine.
The concept
Laboratory diagnostics is a medical discipline that applies in practice standard diagnostic methods for identifying and monitoring diseases, as well as searching and studying new methods.
Clinical laboratory diagnostics greatly facilitates the diagnosis and allows you to choose the most effective treatment regimen.
Laboratory diagnostic sub-sectors are:
- clinical biochemistry;
- clinical hematology;
- immunology;
- virology;
- clinical serology;
- microbiology;
- toxicology;
- cytology;
- bacteriology;
- parasitology;
- mycology;
- coagulology;
- laboratory genetics;
- general clinical research.
Information obtained using various methods of clinical laboratory diagnostics reflects the course of the disease at the organ, cellular and molecular levels. Due to this, the doctor has the opportunity to diagnose pathology in a timely manner or evaluate the result after treatment.
Tasks
Laboratory diagnostics is designed to solve the following problems:
- continuous search and study of new methods of analysis of biomaterial;
- analysis of the functioning of all human organs and systems using existing methods;
- detection of a pathological process at all its stages;
- monitoring the development of pathology;
- assessment of the result of therapy;
- accurate definition of the diagnosis.
The main function of the clinical laboratory is to provide the doctor with information about the analysis of the biomaterial, comparing the results with normal values.
Today, 80% of all information important for diagnosis and treatment control is provided by the clinical laboratory.
Types of material
Laboratory diagnostics is a way of obtaining reliable information by examining one or more types of human biological material:
- Venous blood - taken for hematological analysis from a large vein (mainly on the bend of the elbow).
- Arterial blood - most often taken to assess CBS (acid-base condition) from large veins (mainly from the thigh or area under the collarbone).
- Capillary blood - taken for many studies from the finger.
- Plasma - it is obtained by centrifugation of blood (i.e. dividing it into components).
- Serum - blood plasma after separation of fibrinogen (a component that is an indicator of blood coagulation).
- Morning urine - collected immediately after waking up, is intended for general analysis.
- Daily diuresis - urine, which collects in one capacity during the day.
Stages
Laboratory diagnostics includes the following steps:
- preanalytical;
- analytical;
- postanalytical.
The pre-analytic phase involves:
- Observance by a person of the necessary rules for preparing for analysis.
- Documentary registration of the patient when appearing at a medical institution.
- Signature of tubes and other containers (e.g. with urine) in the presence of the patient. The name and type of analysis are applied to them by the hand of the medical worker - he must pronounce these data aloud to confirm their accuracy by the patient.
- Subsequent processing of the taken biomaterial.
- Storage.
- Transportation.
The analytical stage is the process of direct research of the obtained biological material in the laboratory.
The postanalytical phase includes:
- Documentation of results.
- Interpretation of the results.
- Formation of a report containing: data of the patient, the person conducting the study, medical institution, laboratory, date and time of sampling of the biomaterial, normal clinical limits, results with relevant conclusions and comments.
Methods
The main methods of laboratory diagnostics are physical and chemical. Their essence is the study of the material taken for the relationship of its various properties.
Physicochemical methods are divided into:
- optical;
- electrochemical;
- chromatographic;
- kinetic.
The most commonly used in clinical practice is the optical method. It consists in recording changes in the ray of light passing through the biomaterial prepared for the study.
In second place in terms of the number of analyzes is the chromatographic method.
Error probability
It is important to understand that clinical laboratory diagnostics is a type of research during which errors can be made.
Each laboratory should be equipped with high-quality instruments; analyzes should be performed by highly qualified specialists.
According to statistics, the main share of errors falls on the preanalytical stage - 50-75%, on the analytical - 13-23%, on the postanalytical - 9-30%. Regularly should be carried out activities aimed at reducing the likelihood of errors at each stage of the laboratory study.
Clinical laboratory diagnostics is one of the most informative and reliable ways to obtain information about the health status of the body. With its help, it is possible to identify any pathologies at an early stage and take timely measures to eliminate them.