Infections are caused mainly by the following types of microorganisms: bacteria, viruses, fungi, protozoa. Their detection is a reliable sign of the infection process.
The laboratory has an arsenal of methods, but only 5 of them are the most widely used:
Cultural method (sowing method)
Identifies a pure culture of the pathogen. The method is reduced to the fact that the resulting material (smear from the mucous membrane, blood, pus, feces, etc.) is sown to nutrient media. Environments may contain different components. But the essence comes down to the following: microorganisms must give growth and colonies. If there is a growth of pathogenic microorganisms, their sensitivity to drugs: antibiotics and bacteriophages is determined.
Serological method (method of antibodies to the pathogen)
It also allows you to make a diagnosis. The method is based on the detection in the blood of antigens of the causative agent or antibodies – special proteins that are formed in the body in response to the presence and reproduction of pathogens. Antibodies are formed gradually, so they can be detected in the blood only by the end of the first week of infection. This is the main disadvantage of the method.
Molecular and biological method
Determines the genetic material of the causative agent – DNA or RNA in samples (scraping with mucosa, blood, urine, feces, etc.). To capture small concentrations of DNA or RNA, you need to increase the number of copies. For this purpose, the tested sample is placed in the device – amplifier, which allows increasing the number of DNA copies in geometric progression. For this method of diagnostics, correct biomaterial sampling is of utmost importance.
Microscopic method (examination under a microscope)
It implies preparation of preparations on glass. Material: blood, detachable mucous membranes, etc. Glasses can be painted or unpainted, depending on the type of infection. The doctor examines the drug under a microscope and gives the result based on visual evaluation: size, shape, attitude to the dyes, etc.
Method of gas chromatography
Identifies pathogens by products of their life activity. Material: blood, urine, feces, detachable wounds, mucous membranes.
Diagnosis of anemia
A condition in which the blood mass in the body decreases, or the blood content of hemoglobin and red blood cells decreases, is called anemia or anemia. But it is the red blood cells and the hemoglobin contained in them transport oxygen to the internal organs and tissues, ensuring their proper functioning. Anemia develops for various reasons and is associated with many diseases. It is possible that this disease may also occur after surgery.
Iron deficiency anemia
Iron deficiency anemia is most common, which is manifested in half of pregnant women and in every fifth woman of childbearing age. Iron deficiency reduces the hemoglobin content in red blood cells. The reason for this is the consumption of products with a low content of iron, impaired absorption of iron by the digestive system. It is possible to occur in infants, if the mother had iron deficiency.
Anemia may accompany cancer and other long-term chronic diseases (endocrine system diseases, kidney diseases, HIV, tuberculosis, diabetes mellitus), when the formation of red blood cells decreases. The disease may also be caused by other causes: a lack of folic acid and vitamin B12 in the body; excessive blood loss during heavy menstruation, stomach ulcer, bleeding hemorrhoids, stomach or colon cancer. With very different causes of the disease symptoms are very similar: increased fatigue and weakness, headache, fainting, shortness of breath, rapid heartbeat, dizziness, pale skin, cramps in the legs. Seeing a doctor is mandatory at the first suspicion of anemia, because it may be the first signal of more serious diseases.
Methods of diagnosis of anemia
The general blood test is the main method to diagnose anemia. But in order to establish an accurate clinical picture of the disease may be assigned tests for ferritin, vitamin B12, transferrin, iron serum and other tests. It is important to know that conducting full studies for anemia will help to determine as accurately as possible the causes of the disease. This will allow the attending physician to make an optimal treatment plan.