Stool analysis is one of the first steps in the study of the patient's condition and subsequent diagnosis. Bleeding in the organs of the gastrointestinal tract is a symptom of a pathology, which in many cases can significantly threaten the life of the patient. Severe bleeding can be detected visually, but in the first stages of the disease, the presence of blood in the stool can be determined only by analysis.
The essence of the study
In order to understand how the presence of latent blood is determined during the study of stool, it is necessary to know what this analysis is. It is based on Gregersen's method, during which the change in the level of hemoglobin formed when blood cells are destroyed in the lower parts of the intestine is determined. A reagent is added to the sample, which helps to detect the presence of hemoglobin.
In the analysis, a significant disadvantage is the hypersensitivity of the method of investigation. The reagent has the property of reacting to the presence of even the slightest amount of hemoglobin, including the one contained in the meat of the animal used on the eve of the patient. Therefore, preparation for the analysis of feces for occult blood is a separate process.
Preparation for analysis
Before assigning a patient to the study, the doctor should instruct the patient. Before taking the test for analysis, during the week it is forbidden to use iron preparations and supplements that help increase the level of hemoglobin. Also this ban applies to the following products:
- meat;
- a hen;
- a fish;
- by-products;
- apples;
- spinach;
- white beans.
The consumption of these products will prevent you from obtaining a true result of the study. Another important condition that must be observed before the analysis is the absence of invasive investigations of the gastrointestinal tract two days before the test. Therefore, it is forbidden to do enemas, fibrogastroscopy and irrigoscopy, which can negatively affect the mucosa, because of what the test results will be incorrect.
It is necessary to refrain from the usual morning and evening procedure - brushing your teeth, as this can provoke bleeding gums.
Adherence to all recommendations will ensure the effectiveness of the analysis.
False result
It so happens that the patient regularly observed all the recommendations of the doctor, but the analysis of feces for latent blood gave a positive result, which later was not confirmed. This is because there are several factors that negatively affect the test. First and foremost, it is worth noting and nosebleeds and bleeding gums, which the patient himself can not notice, because to violate the authenticity of the result requires very little blood.
The reason, which does not belong to chance, but is considered more serious, is periodic bleeding. If it is not constant,
Factors that prevent the truthful result are observed extremely rarely, but still experts have learned to protect themselves from them by re-collecting stool for hidden blood. Thus, the patient prepares to conduct the test within a week, but after completing the research, he still follows the recommendations, since the second analysis is carried out in two to four days. Because of what we can conclude that, with the existing risks, the study of feces for occult blood is still a reliable method of diagnosis that can be trusted.