What is Yersinia?
Yersinia is a genus of bacteria associated with a number of medical conditions. Several species of Yersinia can infect humans and bring about a variety of symptoms.
Yersiniosis is an infectious disease caused by Yersinia bacteria. It’s most often diagnosed in children between the ages of five and ten. Most human yersiniosis cases in the United States result from infection with the bacterium Yersinia enterocolitica. The disease is most likely to be contracted when consuming undercooked meat products, especially pork, as well as tofu, unpasteurized milk, or water contaminated with the bacteria. Although most cases of the infection are sporadic, large outbreaks around a single contaminated source have occasionally been documented.
Yersinia pestis is the bacterium responsible for plague. Research suggests that infection with certain Yersinia bacteria may play a role in triggering Crohn’s disease, which is an inflammatory autoimmune illness affecting the gut. Some Yersinia species can also cause a form of arthritis that’s brought on by an infection in the body that spreads to the joints.
Pseudoappendicitis is also linked to the genus Yersinia. It presents similarly to appendicitis and is therefore often misdiagnosed, hence the name.
What Are the Symptoms of Yersinia Infections?
Yersiniosis can lead to a broad range of symptoms, including fever, diarrhea, vomiting, and abdominal pain and cramps. The pain tends to be concentrated at the right side of the stomach area, and therefore it’s often confused with appendicitis. Younger children are the most likely to have severe diarrhea, which may also have blood in it. Symptoms usually first begin within four to seven days after the bacteria have entered the body and last for at least one week. The infection normally resolves on its own within a month in people with healthy immune systems.
Serious complications of yersiniosis are rare. A small number of patients experience rashes, joint pain, ileitis (inflammation of a part of the small intestine), erythema nodosum (painful red lumps on the legs and the trunk) and acute arthritis. In very rare cases, the infection can lead to sepsis, which is a life-threatening condition caused by the immune system’s overreaction to an infection.
What’s the Connection Between Yersinia and Lyme Disease?
Yersiniosis is a possible differential diagnosis of Lyme disease. Both conditions may cause joint pain, swelling and stiffness.
Reactive arthritis is a rare but well-documented occurrence in yersiniosis patients. It happens when a particularly persistent Yersinia infection becomes chronic and the resulting inflammation spreads to some of the joints.
Borrelia burgdorferi, the bacteria causing Lyme disease, can also infect the joints when the illness isn’t diagnosed early enough. Chronic Lyme disease is a result of an immune dysfunction that allows the bacteria to proliferate and travel to different tissues and organs.
Thyroiditis is another potential complication of yersiniosis that has also been seen in patients with chronic Lyme disease. When it’s left untreated for a long period of time, Lyme disease can lead to various autoimmune symptoms. The resulting widespread inflammation can affect several different organs, including the thyroid gland.
How Do Doctors Test For Yersinia?
The most common test traditionally used in the diagnosis of yersiniosis is stool culture. Many doctors consider this method to be the most reliable way of confirming the presence of Yersinia enterocolitica. Other conventional tests include tube agglutination enzyme-linked immunosorbent assays, radioimmunoassays, computed tomography (CT) scans, and colonoscopies. Joint aspiration may also be considered in cases of joint disorders associated with a Yersinia infection.
How Does The New ELISpot Test For Yersinia Work?
ELISpot is a new, modern laboratory test that can be used to determine the presence of Yersinia bacteria in the body. It’s known as a highly effective diagnostic technique, and it’s offered by Infectolab.
The ELISpot test can accurately detect two important molecules in the blood, helping doctors obtain a clearer picture about the state of the infection. These two molecules are interleukin-2 (IL-2) and type II interferon (IFN-gamma). They both help regulate immune function. They’re produced by T-cells, which are a type of white blood cell that plays an essential role in maintaining the body’s natural defense mechanisms against pathogens.
Once the Yersinia infection has cleared up, only IL-2 molecules are expected to be found in the patient’s blood sample. The T-cells that produce IL-2 are responsible for recognizing and destroying the Yersinia bacteria if they ever encounter them again in the future.
If the ELISpot test indicates that both IL-2 and IFN-gamma molecules are still present in the patient’s blood, that means that the infection is still active, and the immune system is still fighting the invading pathogens. Once the bacteria have become inactive, T-cells will stop producing IFN-gamma molecules.