In vitro diagnostics in medicine and veterinary medicine: basic concepts and difference.

In recent years, clinical laboratory diagnostics have received a big leap in their development, whose is the main task detection or confirmation of pathology that would be impossible refuted or confirmed by organoleptic methods.

In vitro diagnostics are carried out using various biological fluids, such as whole blood, plasma, serum, sputum, cerebrospinal fluid, etc. The process of conducting clinical laboratory tests is divided into three stages:

  • Preanalytical phase – this stage includes collecting the necessary data about the patient, taking samples of biomaterial;
  • Analytical phase – it takes place in the laboratory and consists of preparing the analyzer, calibrating the analytical system, conducting quality control, conducting research on patient samples, as well as processing and recording the results;
  • Postanalytical phase – this stage also takes place in the laboratory and includes writing reports on research results, compiling statistical reports, as well as support and servicing the analytical system.

These stages are carried out as for clinical laboratory diagnosis of humans, and in animal screening. Undoubtedly, there are differences in the conduct of clinical laboratory tests, but they are mainly contained in the preanalytical phase, namely in the methods and rules for collecting biological material. For example, for clinical veterinary diagnosis in monogastric animals, blood is taken before feeding and in the morning, and for ruminants in the morning, 4 hours after feeding. Whereas in clinical medicine, a person takes blood only in the morning and on an empty stomach. At the preanalytical phase, the method of laboratory research of the obtained biomaterial is selected. The methods for studying biomaterial for veterinary medicine are the same. The most commonly used methods for in vitro diagnostics: chemical, immunochemical, hematological, microbiological, immunological and genetic. Some of these tests are nonspecific, and in order to accurately diagnose the level of damage to a particular organ and minimize the likelihood of false positive and false negative results, special training is required in the form of limiting a certain type of products, drugs. [1,2]

Between clinical veterinary and medical diagnostics, there are significant differences in analytical systems. For veterinary in vitro diagnostics, the analyzers provide a wide range of profile settings for different types of animals. Each type of animal is distinguished by physiological parameters of blood. For example, hemoglobin in the blood of dogs averages 12-18 g%, when, as in cats, the hemoglobin concentration ranges from 8.0-17.3 g%. Analyzers for clinical medical laboratory diagnostics provide for tuning the system only for human blood. These reagents are designed to detect specific diseases in animals and birds that are absent in humans. One more important difference that exists between analyzers that are designed to conduct quantitative studies of blood cells: in veterinary hematological analyzers, the measurement cycle can be performed with a single addition of a lysing solution, and with a double one, when, as in hematological analyzers of human blood, a lysing solution is added once. [2,3,4].

  1. Типичные ошибки на преаналитическом этапе проведения лабораторных исследований. О.В.Бражникова, Н.В Гавеля, И.Д Майкова.
  2. Статья Е.Б. Бажибиной «Методический подход к интерпретации результатов биохимических исследований» в Российском ветеринарном журнале. Мелкие домашние и дикие животные, № 2, 2012 г., стр. 8-14.
  3. Клиническая ветеринарная лабораторная диагностика. Справочник для ветеринарных врачей. М Медведева.
  4. Биохимические показатели у кошек и собак, Ю. В. Конопатое, В. В. Рудаков, Санкт-Петербургская государственная Академия ветеринарной медицины, 2000 г.