The human gastrointestinal (GI) tract is highly complex and plays a central role in the body as a source of nutrients absorption and wellbeing. When the regulators are healthy, it provides immunity from pathogen attacks as well as the ability to tolerate dietary antigens and the microflora of the human body. In autoimmune GI diseases, for some reason this balance is upset and the immune system starts attacking the body’s own tissues or cells.
Introduction of autoimmune GI diseases
Autoimmune gastrointestinal diseases is a group of diseases that affect the gastrointestinal system, these are diseases in which the immune system attacks the body. Such conditions are usually long lasting and may worsen the quality of life of patients suffering from them. Common autoimmune GI diseases include:
- Celiac Disease: It is a hereditary condition that occurs when the consumed gluten affects the small intestine’s lining by launching an immunological reaction that is hostile to the body. Gluten is a protein present in wheat, barley, and rye that causes the chronic autoimmune disease celiac disease. It primarily affects the small intestine, leading to inflammation and damage to the intestinal lining, which impairs nutrient absorption. It can be diagnosed by several tests like Serological test, Genetic Testing, Biopsy.
- Crohn’s Disease: A form of IBD that can afflict all parts of the GI including the esophagus, stomach, small intestine, large intestine, and the rectum. It leads to inflammation which then leads to such symptoms such as stomach aches, diarrhea and having a slim physique. It can be diagnose by various method: Medical history and physical examination, Laboratory test, imaging studies (CT scans, MRI and contrast X-ray), Endoscopic procedure
- Ulcerative Colitis: One more kind of IBD, ulcerative colitis is the inflammation and ulcers in the colon and rectal areas of the large intestine.
- Autoimmune Hepatitis: Autoimmune hepatitis is mainly characterized as affecting the liver but it presents gastrointestinal effects. It is characterized by an unhealthy aggression from the body’s immune system on liver cells thus causing inflammation and sometimes liver damage.
Causes and Risk Factors
Autoimmune GI diseases have not been established to be caused by a specific factor but rather by a combination of inherited traits and some factors in the environment. Factors that may contribute include:Factors that may contribute include:
1. Genetics: A genetic predisposition is also a determinant; those with a family history of autoimmune diseases are more prone. The genetic risk of gastrointestinal (GI) diseases involves understanding how inherited genetic variations can predispose individuals to various GI conditions. Some key points include:
- Family History: A strong family history of GI diseases can indicate a higher genetic risk. Conditions such as inflammatory bowel disease (IBD), including Crohn’s disease and ulcerative colitis, often have a hereditary component.
- Genetic Mutations: Specific genetic mutations have been linked to certain GI diseases. For example, mutations in the NOD2 gene are associated with an increased risk of Crohn’s disease.
- Polygenic Risk: Many GI diseases are influenced by multiple genetic factors. For example, colorectal cancer risk is affected by several genetic variations in combination with lifestyle factors.
- Hereditary Syndromes: Certain hereditary syndromes significantly increase the risk of GI diseases. Lynch syndrome and familial adenomatous polyposis (FAP) are two examples that elevate the risk of colorectal cancer.
- Genetic Testing: Genetic testing can help identify individuals at high risk for specific GI diseases, allowing for early intervention and personalized treatment strategies.
- Epigenetics: Environmental factors can influence gene expression, impacting the risk of developing GI diseases. Diet, stress, and infections can modify genetic predispositions through epigenetic changes.
Understanding these genetic risks can lead to better prevention, early detection, and tailored treatments for GI diseases.
2. Infections: Some pathogens may cause autoimmune reactions in the body either bacterial or viruses.
Some infections are known to trigger or exacerbate GI conditions, especially in genetically susceptible individuals. Here are a few examples:
- Helicobacter pylori (H. pylori): Peptic Ulcer Disease and Gastric Cancer – Infection with H. pylori is a significant risk factor for developing peptic ulcers and gastric cancer. Genetic variations in immune response genes can influence the severity of the disease and the body’s response to the infection.
- Viral Infections:
Hepatitis B and C – Chronic infections with hepatitis B and C viruses can lead to liver diseases, including cirrhosis and hepatocellular carcinoma. Genetic factors can affect the progression of these diseases.
Epstein-Barr Virus (EBV) – This virus has been linked to an increased risk of certain cancers, including gastric cancer. Genetic susceptibility can play a role in the development of these cancers following EBV infection.
- Bacterial Infections :
Campylobacter and Salmonella – Infections with these bacteria can trigger post-infectious irritable bowel syndrome (IBS) in genetically predisposed individuals. Some genetic markers are associated with an increased risk of developing IBS after such infections.
- Parasitic Infections:
Giardia lamblia – This parasite can cause giardiasis, leading to chronic GI symptoms in some individuals. Genetic susceptibility may influence the persistence and severity of symptoms.
- Enteric Pathogens:
Norovirus and Rotavirus – These viruses cause acute gastroenteritis. In some cases, particularly in children, genetic factors can influence the severity of the infection and the likelihood of complications.
- Microbiome Imbalance:
Dysbiosis – An imbalance in the gut microbiome can be triggered by infections and can contribute to the development of conditions like IBD in genetically susceptible individuals. Genetic variations in genes related to the immune system and gut barrier function can influence susceptibility to dysbiosis.
Infections can interact with genetic factors to influence the risk and progression of GI diseases. Understanding these interactions helps in developing preventive strategies and targeted treatments for those at higher risk.
3. Dietary Factors: Gluten is one of the substances that can cause an exacerbation of the patient’s condition in celiac disease.
- Fiber intake.
- Red and processed Meat.
- Fats and oils.
- Dairy products.
- Alcohols consumption.
- Processed foods and sugars.
- Gluten (cause auto immune disorder – celiac disease)
- Probiotic and prebiotic.
4. Environmental Factors: These diseases may be caused and/or worsened by smoking, stress, and pollution.
Symptoms and Diagnosis
Autoimmune diseases of the gastrointestinal tract manifest different symptoms based on the specific pathology and the affected area of the GI tract. Common symptoms include:
- Abdominal pain and cramping are some of the common features of a patient who may be preparing for an appendicitis surgery.
- Protracted diarrheal illness or constipation
- In the stool there can be identified blood of various shades, ranging from bright red and dark maroon.
- Unexplained weight loss.
- Fatigue and weakness.
- Nutritional deficiencies.
A restricted type of dytonomia that affects the dynamics of the digestive system is called autoimmune gastrointestinal dismotability (AGID). Despite being abnormal, the disease can cause serious symptoms, such as nausea and sudden weight loss.
A strong immune system protects the body from disease and infection. However, when the immune system is not functioning properly, it starts attacking healthy tissues, cells and organs. These attacks, also known as autoimmune diseases, can affect every region of the body, spoil physical function and perhaps a threat to life.
- Massive Cell Heart Disease. An very uncommon autoimmune condition called giant cell myocarditis causes inflammation in the heart.
- Lupus…
- Multiple sclerosis (MS)…
- Vasculitis…
- Neuropathy caused by anti-NMDA receptors.
