The coliforms They are a group of bacteria that group a series of characteristics in common. They all belong to the Enterobacteriaceae family and are generally part of the normal bacterial flora of the digestive tract of some animals..
It owes its name to the best known member of this group, the bacterium Escherichia coli. However, coliform bacteria group four bacterial genera: Escherichia, Enterobacter, Klebsiella Y Citrobacter.
From an ecological point of view, these bacteria are important because they constitute an indicator of the levels of contamination of bodies of water. The presence of these bacteria indicates that the water is contaminated with fecal matter. Likewise, some are important pathogens for man..
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The taxonomic classification of coliform bacteria is as follows:
Despite the fact that coliform bacteria are made up of several genera, they have certain characteristics that they share.
This group of bacteria are characterized by being rod-shaped, which is why they are known as bacilli. They are elongated, measuring approximately 3 to 6 microns, and some have rounded edges, while others have curved edges..
These bacteria are scattered throughout the world geography, mainly in soils. Some grow on decaying organic matter.
Likewise, they are an integral part of the bacterial flora of the intestine of some warm-blooded animals such as humans..
Coliform bacteria are gram negative. This means that when they are subjected to the Gram staining process, they do not acquire the typical violet coloration, but rather have a fuchsia hue..
This is due to the configuration of its cell wall, which is made up of peptidoglycan and is very thin. Being thin, it is not able to retain the gram dye particles.
An aerobic organism is one that must be in an oxygen-rich environment in order to develop. Likewise, facultative anaerobes can develop in environments where there is oxygen availability, or lack of it. Some of the coliform bacteria are strict aerobic, while others are facultative anaerobic.
Coliform bacteria do not have the ability to synthesize any of the enzymes from the group of cytochrome c oxidases. This means that they cannot use oxygen as an acceptor in the electron transport chain..
Gram negative bacteria, including coliforms, are characterized by not producing spores. In this way they lack that protection mechanism when environmental conditions become hostile..
One of the most distinctive characteristics of coliform bacteria is that they have the ability to ferment lactose, generating gas in the process within 48 hours at average temperatures of 37 ° C. However, there is another group of bacteria within coliforms, which can perform the process at much higher temperatures of between 42 and 45 ° C..
Many people tend to think that coliform bacteria are all fecal in origin. However, this thinking is wrong, since there are some members of this group of bacteria that do not meet this characteristic..
This is why specialists have decided to classify coliform organisms into two large groups: total and thermotolerant..
The group of total coliform bacteria is made up of a wide variety of bacteria that have a bacillary shape and are gram-negative, in addition to being facultative anaerobes, which means that they can develop both in the presence and in the absence of oxygen..
Total coliforms encompass all coliform bacteria, within which there are genera that can be pathogenic for humans, as well as others that are totally harmless..
These bacteria are quite useful as indicators of the levels of contamination or cleanliness of the waters. Taking into account that many of the coliform bacteria proliferate and develop in fecal matter, they constitute an excellent indicator of water contamination by fecal matter. The more coliforms there are in the water, the more serious and intense is its contamination.
This is a subgroup within the total coliform bacteria. They are known as thermotolerant because they have the peculiarity of being able to ferment lactose at extremely high temperatures, between 44 and 45 ° C..
These bacteria are also known as fecal coliforms because they generally originate in the intestines of some animals. Because of this, they are contained in fecal matter..
The genera that make up the group of thermotolerant bacteria are Escherichia, Enterobacter Y Klebsiella, being the most representative of all bacteria Escherichia coli.
Due to their known faecal origin, thermotolerant coliform bacteria, especially the Escherichia coli, they are a very effective and unequivocal indicator of the contamination of bodies of water by fecal matter.
The group of coliform bacteria is made up of a total of four widely known genera: Escherichia, Enterobacter, Klebsiella Y Citrobacter.
Now, although these four genres have similar characteristics, they also present distinctive characteristics that differ from each other..
This is a genus of bacteria that is well known and studied, thanks to its pathogenic potential. They are bacteria that are rod-shaped with rounded edges. They measure approximately between 0.5 and 3 microns and are part of the intestinal flora of some animals, living in them as a commensal.
This is so for a large part of the species that make up this genus. However, there are species that are considered pathogens, the most representative of this group being the bacteria Escherichia coli.
The pathologies caused by bacteria of the genus Escherichia They are mainly focused on the digestive level, such as gastrointestinal syndromes, whose main symptoms are diarrhea and colic. Likewise, these bacteria can cause disorders in the genitourinary tract..
The gender Enterobacter It is very well known in the medical field, since it is the cause of a large number of opportunistic infections. They are found mainly in soils (some are decomposers of dead organic matter), in water and in some dairy.
One of their most outstanding characteristics is that from a nutritional point of view they are very undemanding. Although this genus encompasses a large number of species, the best known and considered to be the most important are: Enetrobacter cloacae, Enterobacter sakozaki Y Enterobacter aerogenes. These are those that are generally associated with pathological processes in which they are the causal agents..
The bacteria belonging to this genus are bacillary in shape, thick and short, with curved edges. Likewise, they do not present any type of flagellum or appendix that helps them in locomotion, in such a way that they are immobile bacteria. They tend to be in pairs or very short chains.
Among its characteristics it can be mentioned that its cells are surrounded by a highly resistant capsule, made up of polysaccharides. That capsule is one of its distinctive elements.
These bacteria are found mainly in aquatic habitats and tend to reproduce very quickly when the nutrients they require are available..
Within this genus there are approximately 13 species, however, the most important from a sanitary and health point of view are: Klebsiela pneumoniae, Klebsiella ozaenae, Klebsiella oxytoca Y Klebsiella rhinoscleromatis.
These are considered pathogens and are responsible for pathologies such as urinary tract infections, infections of the digestive tract, upper respiratory tract and respiratory tract in general..
This is one of the genera of coliform bacteria that causes a wide variety of pathologies in humans. These pathologies include brain abscesses and urinary tract infections..
They are mobile bacteria, rod-shaped with an average size of between 2.5 and 6 microns in length. It shares with the rest of the coliform bacteria certain characteristics such as, for example, that they are catalase positive, reduce nitrates to nitrites and are gram negative. It is also indole positive and can ferment glucose.
Some of its species are pathogenic, the best known and most studied being the Citrobacter freundii.
The four genera that make up the group of coliform bacteria are responsible for various pathologies in humans. Sometimes they are opportunistic infections, generated by the individual's immunosuppression.
It is the most common infection caused by coliform bacteria. Taking into account that these bacteria are regular inhabitants of the digestive tract, it is common for them to spread from the anus to the urethra. This occurs more frequently in women, since the distance between the anus and the urethral orifice is less than in men..
People with a UTI have the following symptoms:
However, if these symptoms are not treated in time, the infection can spread from the lower urinary tract to the kidneys. If this occurs, the following signs and symptoms occur:
It is important to attend to these symptoms as soon as they appear, since otherwise it can generate more serious clinical conditions, such as kidney failure..
This type of pathology can be diagnosed through several tests:
-Routine urine test: In this, the specialist makes a complete study of the urine, in which he could observe some indication of urinary infection, such as traces of blood, presence of leukocytes and even bacterial cells.
-Imaging studies: the most widely used methods are renal and pelvic ultrasound and tomography. Through these non-invasive medical procedures, organs such as the kidney, ureters, urethra, and bladder can be visualized. In this way, it can be determined if there is any structural abnormality that may be the result of an infection..
-Urine culture: it is the most accurate test to diagnose a urinary infection due to any of the coliform bacteria. In this, what is done is that from a urine sample, a culture is carried out in the laboratory, using the most indicated culture media. If any of the coliform bacteria are causing the infection, they will grow in the prepared culture..
Taking into account that this infection is caused by bacteria, the most used therapy is antibiotics. Among the antibiotics most used to solve this infection are:
It is important to adhere to the treatment time. In the case of recurrent infections, the doctor will decide the most appropriate treatment scheme for each particular case..
They are the infections that develop at the level of the gastrointestinal tract. It is common for coliform bacteria to be responsible for these types of infections, since they are normally part of the bacterial flora of the digestive tract..
The most common symptoms for infections of this type are:
It is important that when you have an intestinal infection that causes watery stools, a stool exam is performed.
In the stool examination, the specialist will study some parameters such as the presence of hidden blood or mucus, which are unequivocal evidence of an infection..
Likewise, it is possible that a stool culture is made in which a culture is performed with a stool sample to verify if any bacteria are growing and developing there. In the event that there is any of the coliform bacteria there, it will begin to reproduce, forming colonies and allowing their identification..
If the symptoms are mild, the most common is for the doctor to recommend that the patient increase the intake of fluids to restore those that he has lost in frequent bowel movements..
Likewise, it is possible that he prescribes some type of antibiotic to eradicate the bacteria causing the pathology. However, as it should, the doctor will be the one who decides what is the treatment pattern to follow according to the patient and according to the severity of the case..
This is an infection that affects the lung tissue. Some bacteria of the genus Klebsiella are known causative agents of pneumonia. If it is not attended to in time, it can be life threatening.
Among the most common symptoms of pneumonia are:
There are several diagnostic methods for this pathology. Among the most successful are imaging tests (x-ray or tomography) and sputum culture.
In imaging studies, what is sought is to determine if at an anatomical and structural level there is any variation in the normal arrangement of the lungs that may be caused by pneumonia.
In the case of sputum culture, a sample is taken from the expectoration that is made by coughing and a bacterial culture is performed. Here, through different identification methods, it is sought to determine exactly which is the microorganism causing the pathology. This is perhaps the most accurate diagnostic method, since it clearly identifies the causative agent of the disease.
When pneumonia is of bacterial origin, the first line of treatment preferred by specialists is the use of antibiotics. Among the antibiotics most used in the treatment of pneumonia are:
Of course, the doctor will be the one who determines the best antibiotic therapy required..
Bacteria of the coliform group can generate, in extreme cases, other infections apart from those already mentioned. These include:
These infections occur in a very small percentage of the population, especially in those who have a problem at the level of the immune system, which makes them prone to developing this type of infection.
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