Quellung Reaction

The Quellung Reaction is one of the laboratory diagnostic methods used to determine the presence of certain types of bacteria in samples of biological material. This method is based on the ability of antibodies to bind to antigens inside bacterial cells and cause them to swell.

The main purpose of the Swelling reaction is to determine the presence or absence of certain species of Streptococcus pneumoniae. In addition, it can be used to identify serotypes that may be associated with various diseases such as pneumonia and meningitis.

The principle of the reaction is very simple. Capsules containing antigens are isolated from the bacterial sample. Specific antibodies are then added to the sample and bind to these antigens. If antibodies bind to antigens, the latter begin to swell and become visible under a conventional light microscope. This makes it easy to determine the presence or absence of bacteria, as well as their serotype.

The Swelling Test is a very sensitive and specific diagnostic method that can be used to detect even small amounts of bacteria in biological samples. It also has a high degree of reproducibility, allowing results obtained in different laboratories to be repeated.

In conclusion, the Swelling test is an important laboratory diagnostic technique that can be used to detect certain types of bacteria in biological samples. It has high sensitivity and specificity, and can be useful in diagnosing various diseases associated with certain types of bacteria.

The swelling test is a method used to diagnose bacterial infections such as pneumonia. It is based on the fact that when the bacteria Streptococcus pneumoniae infects the body, they secrete a capsule that protects them from the immune system. When these bacteria enter the body, the antibodies that are already in the body bind to the antigens found on the surface of the capsule. Then, as the bacteria begin to multiply, their capsules swell and become visible under a regular light microscope.

This method is quick and easy to use, and can be used to diagnose many different types of infections. However, if the patient is already taking antibiotics, the swelling response may be less accurate as the antibiotics may change the structure of the capsule.

The swelling test is one of the most common methods for diagnosing pneumonia and other bacterial infections. It helps doctors quickly and accurately determine the cause of the disease and prescribe the correct treatment.

In its homeland - Africa - the bacterium pneumococcus has gained fame as a pathogen leading to a large number of deaths. Therefore, the immune system of African representatives is capable of interacting with pneumococcal antigens.

The first mention of the swelling reaction was recorded in the course of history 400 years ago, but the details still remain in the shadows. In the middle of the 20th century, scientist E. Henke described the consequences of this event. However, the final details of the reaction were studied only in the 60s thanks to Dr. R. Dalton and her assistants.

The complexity of swelling reactions is associated with the need to artificially create conditions that are not typical for the habitat of streptococci. It is important that the bacterial capsule is on the surface of the antigen, and at the same time immune cells penetrate into it. In addition, the antigen must be colloidal. Only in this case does active interaction of antibodies with capsules occur.

Often, manifestations of the reaction can be seen within minutes. After an hour or two, the fabric becomes dull and the surface color changes. And in the later stages it is clear that they have acquired a yellowish or white tint. After a few weeks, negative changes occur: the tissues become covered with purulent