Fungus is any group of unicellular, multicellular, or spore producing organism, including yeast, molds, and mushrooms in the domain Eukaryota. Most fungi are harmless, but some are pathogenic and can cause infections in humans. The most common pathogenic fungi include Candida and Aspergillus.
Candida is a type of yeast that naturally exists in the human body including the skin, digestive tract, flora of the mucous membranes of the respiratory tract, and female reproductive system. Candida usually coexists with other types of bacteria such as Lactobacillus acidophilus, a beneficial bacterium that controls the growth of Candida. Individuals who have an altered natural flora or are immunocompromised are more susceptible to candida overgrowth that cause infections, called candidiasis. There are more than 20 different types of candida that can cause infection however, C. albicans is the most common pathogen among the candida species and are classified as an opportunistic fungus. At low populations, Candida is harmless and will be kept in check by the immune system.
Causes of Candida Overgrowth:
Candida can grow out of control and populate the mouth, throat, genitals, skin, and digestive tract causing yeast or fungal infections in other parts of the body. Several factors can contribute to Candida overgrowth with the most significant factor being the use of antibiotics. Antibiotics can remove bacterial competition, such as Lactobacillus acidophilus that controls the growth of Candida and other pathogenic microorganisms by producing lactic acid and hydrogen peroxide. Furthermore, low stomach acidity from low acid production due to stomach lining degeneration, and the use of proton pump inhibitors can’t fully sterilize the food before it travels into the intestines, which allows Candida and other pathogenic bacteria to enter, grow, and multiply in the intestines. Other factors include, diet, use of glucocorticoids, poor immune system, and stress.
Various glucocorticoids such as steroid‐based drugs including inhalers, anti‐inflammatories, contraceptives, etc have the same results as the use of antibiotics in the development of candidiasis. Glucocorticoids are potent anti‐inflammatories that suppress cell‐mediated immunity, the major defense mechanism against fungal infections, which causes a decrease in the function and numbers of lymphocytes including both B cells and T cells. Glucocorticoids also raise blood glucose which further impairs the cell‐mediated immunity. Since glucocorticoids compromise the immune system, they significantly increase the susceptibility of the stomach, esophagus, and intestines to Candida infections.
Stress is another important factor for the development of Candida in the digestive tract due to its negative effects on the immune system. In reaction to stress, the adrenal glands release Cortisol, a steroid hormone that belongs to the glucocorticoid family, which can suppress the immune system and increase blood pressure and blood sugar. Continued secretion of steroids by the adrenal glands can exhaust the adrenal glands which can cause low production of adrenaline, the fight or flight hormone. Adrenaline regulates several different systems including the immune system. A decrease in adrenaline can cause chronic fatigue and drain the immune system. Therefore, the immune system is unable to respond properly to pathogens like the Candida yeast.
Candida Overgrowth Pathogenesis:
Candida overgrowth can cause local carbon deprivation. When local sugar levels become low, Candida can adapt to these nutritional changes by catabolizing amino acids as a carbon source. When this occurs, ammonia is excreted which raises the environmental pH and triggers new gene expression. Candida can then transition from a colonizing yeast form to its hyphal form which behaves like a pathogenic or virulent fungus that can quickly spread and tightly attach to the epithelial cells and begin invasion as a result of the pH shift.
After Candida has adapted to its filament form, there are a number of physiological changes that occur including alterations in the cell wall structure which allows Candida to adhere to epithelial cells. This adhesive property is one of the key determinants of microbial pathogenesis. In contrast to the colonized yeast form, the filament form expresses glycosylphosphatidylinositol-dependent cell wall proteins called adhesins which mediate the adhesion of Candida to the epithelial cells. Once Candida attaches to the epithelial cells, it can invade through the mucosal membrane, and ultimately, the blood stream to disseminate. Dietary sugars can modify Candida’s adhesive property to a great extent. Candida can adhere to a much higher degree when it is supplemented by glucose compared to other types of sugars such as galactose.
C. albicans virulence mechanisms also involve its production of proteolytic enzymes, secreted aspartyl proteinases (SAP proteins). SAP proteins are an extracellular protease consisting of a family of 10 secreted aspartyl proteinases which play a central role in Candida pathogenicity that allows C. albicans successful colonization and infection of the host. Such proteolytic enzymes from fungi are very potent and widely used in food, leather, detergent industries, and in ecological bioremediation processes. Although SAP proteins are required for survival and growth of both saprophytic and pathogenic species, these enzymes can help C. albicans penetrate very deep into the body and enter into every possible system causing severe structural damage to the cell surface proteins once they adapted to the pathogenic hyphal form. Research results demonstrate that these enzymes also induce an inflammatory response, altering the permeability of epithelial barrier, causing asthma and allergies.
Bacterial Biofilms are densely packed communities of microbial cells that grow on surfaces and surround themselves with secreted polymers. Biofilms are the predominant growth state of many microorganisms. 60-80% of microbial infections including Candida overgrowth in the body are caused by bacteria growing as a biofilm, as opposed to planktonic (free-floating) bacteria. The biofilm allows the cells inside to become more resistant to the body's natural antimicrobials as well as antibiotics. Biofilm microorganisms can be up to a thousand times more resistant to antimicrobial stress than free-swimming bacteria or fungus of the same species. Formation of the biofilm of candida in the digestive tract makes it very difficult to get rid of them once they have overgrown.
Symptoms of Candida Overgrowth:
Candida’s impact on the body is severe; however, it has often been under diagnosed by the current medical community. Candida overgrowth can be responsible for many chronic illnesses and can have a profound health impact to the entire body even if Candida remains confined in a local area. It is rare for Candida to spread throughout the entire body rapidly and become fatal. This life‐threatening situation is usually seen in people with severely compromised immune systems such as AIDS patients. In most cases, Candida just causes discomfort; however, after many years of accumulated effects, Candida can eventually manifest as problems in other organs such as the heart, liver, kidney, blood vessels, and brain which makes it difficult to pinpoint Candida as the cause of the problems.
Depending on the location of the Candida and the patient's health history, patients may have one or more types of symptoms:
Reproductive system:
The most common form of Candida overgrowth is genital yeast infections or vaginal candidiasis in women which causes intense vaginal itching, soreness, redness, vaginal dryness, painful intercourse, and a white clumpy discharge. The candida yeast can also spread to the uterus causing uterine fungal infections. Symptoms include itchiness, burning, and irritation from the uterus area. Severe vaginal yeast infections may cause swelling of the vulva resulting symptoms of painful or frequent urination due to the inflammation of the urinary opening. In men, it can cause a red rash on the penis and itching or burning on the tip of the penis. Candida overgrowth in the mouth is called oral thrush, and symptoms include creamy white lesions on the tongue, inner cheeks, roof of the mouth, gums, and tonsils which can cause redness or soreness and difficulty eating or swallowing. Candida can also affect the skin and nails such as the feet causing athlete’s foot or toenail fungus.
Digestive Tract:
Candida overgrowth in the stomach can cause irritation to the stomach lining. Patients may experience symptoms of gas, bloating, burping, poor digestion, stomach cramps and excessive gas that does not move downward. Candida overgrowth in the intestine can cause irritation to the intestinal lining and patients may experience diarrhea or constipation, abdominal pain or intestinal cramps, gas, stools that contains mucous substance with a milky or cream-like color, or possess film like materials, or oily mucus that tends to float.
Candida overgrowth can cause the gut wall to develop openings which leads to Leaky gut syndrome due to the destructive enzyme activity of the SAP proteins and their irritation to the intestine. When the candida overgrowth moves to a more serious stage, the candida yeast grows hyphae in a filament form which spreads the bowel wall cells apart so that acidic, harmful microorganisms and macromolecules are able to pass through (leak) these openings and enter the circulatory system. The body’s immune system will react to the invader and develop antibodies leading to food allergy with sensitivity and intolerances to previously harmless foods, such as dairy, eggs, and wheat (gluten) as well as symptoms of constipation, diarrhea, bloating, gas and cramps after eating. Due to the Inflammation of the gut lining and immune reaction to the substance entering to the blood stream, patients may experience symptoms of headaches, poor concentrations, brain fog, and irritability. These symptoms are also the symptoms of irritable Bowel Syndrome.
Candida overgrowth and the resulting leaky gut syndrome can directly lead to many other systemic inflammatory and immune-related symptoms beyond food allergies, including rheumatoid arthritis, ankylosing spondylitis, multiple sclerosis, eczema, fibromyalgia, Crohn's disease, chronic urticaria (hives), and inflammatory bowel disease.
Candida in the upper digestive track can infect the colon causing damage to the colon tissue. Patients can experience symptoms of a burning sensation in the colon and anus area with constipation or diarrhea. Candida can also make its way into the peritoneal cavity causing infection and damage to the peritoneal cavity walls and organs. Patients can experience symptom of tenderness and pain in the abdomen. The abdomen can become very hard and solid when touched.
Liver and Pancreas:
Candida and toxins from the intestines can get into the portal vein and infect the liver causing symptoms of liver congestion such as poor stress tolerance, a feeling of anger or anxiety, difficulty falling asleep, and constipation with very hard stools due to poor bile production. When the live yeast fungus enters the liver, it can cause liver inflammation and hepatitis. Patients may experience abnormal skin sensations like "pins and needles", severe insomnia, and genital irritation and inflammation. When this condition is combined with stress and the resulting low oxygen supply to the liver, it can cause Non‐Alcoholic Fatty Liver Disease (NAFLD) which can cause liver fibrotic tissue formation and can progress into cirrhosis.
Fungal infections in the liver can also cause insulin resistance leading to type II diabetes. This is because SAP proteins produced by Candida can destroy the insulin receptors on the livers cell surface and block insulin signal transduction. Under conditions of insulin resistance, the body requires a higher concentration of insulin to maintain blood sugar levels, which puts higher demand on the insulin-producing beta cells in the pancreas that often sets the stage for diabetes. The fungus can also spread to the pancreas causing pancreas irritation and inflammation. Chronic hyper production of insulin and pancreas inflammation can cause early degeneration of the beta cells. Eventually, the beta cells can no longer produce enough insulin to overcome insulin resistance, as a result, blood sugar levels rise to above normal range and patients become prediabetic. Once a person becomes prediabetic, their beta cell function will continue to decrease leading to type II diabetes.
The fungal toxins can overload Kupffer cells in the liver and cause the cells to become hyperactive. Hyperactivity of the Kupffer cells can cause symptoms related to anxiety attacks, obsessive compulsive disorder, and other psychiatric disorders. When Kupffer cells can't handle the toxins within its capacity, it produces chemokines. Chemokines can enter the brain and cause brain inflammation, and patients can experience symptoms such as mood swings, depression, memory loss, poor mental clarity, focal seizures, tremors, or numbness.
Kidney, Bladder, and Prostate:
Infection of the kidney by Candida can cause kidney inflammation with symptoms of difficult urination and water retention. Patients may have sense of urination but cannot urinate. Chronic irritation to the kidneys can lead to the development of chronic kidney disease.
Candida fungal infections of the bladder and urinary tract can cause cystitis due to irritation and damage to the bladder and urinary tract lining. Patients may experience symptoms of frequent urination, urination urgency, pain and burning with urination, and suprapubic pain. The infection can also damage the nervous system and patients may suffer from incontinence.
Candida Fungal infections of the prostate can cause chronic prostatitis due to irritation and damage to the prostate. Symptoms can be similar to prostatitis caused by bacterial infections including difficulty urinating, painful urination, discomfort or pain in the perineum, bladder, testicle, and penis and painful ejaculation.
Bloodstream:
Candida can get into the blood stream and attach to the plasma cells. Depending on the severity, it can be life threatening or the symptoms can be similar to other types of common chronic conditions. Patients may have one or more of the following symptoms: fever or chills, skin rash, generalized weakness or fatigue, low blood pressure, muscle aches, vision changes or signs of an eye infection, headaches and neurological deficits and abdominal pain.
Cardiovascular:
Candida and the toxins can also affect the cardiovascular system including the heart and blood vessels. The main symptom is heart inflammation which can lead to myocarditis or pericarditis. Secondarily, is an interruption in heart function which can cause heart palpitations or tachycardia. Thirdly, is the irritation of the blood vessels which can cause arteriosclerosis and thus narrowing the blood vessels and causes blood vessel inflammation such as phlebitis, vasculitis, spider veins and varicose veins. They can also trigger formation of blood clots causing serious cardiovascular disorders including stroke and heart attack.
Respiratory:
Fungal infections occur in the respiratory tract mainly through inhalation. This can occur when fungus has been suspended into the air because its natural habitat, such as soil, has been disrupted or it may be a type of fungus that lives in the air naturally and only affects individuals with compromised immune systems or allergies.
Environmental fungi that is finely dispersed in the air can infect individuals who have allergic rhinitis and cause allergic fungal sinusitis. Patients can present with symptoms of chronic sinusitis including facial pressure, headache, nasal stuffiness, discharge, and cough. Thick fungal debris and mucin which is a secretion containing carbohydrate-rich glycoproteins can be accumulated in the sinus cavities and cause sinus congestions or blockage which allow anaerobic bacteria to grow causing a green or yellow mucus discharge from the nose. As long as the fungi remains, so will the irritation which causes nasal membrane damage and degeneration. Patients may experience symptoms of nasal airway dryness, burning sensation and prone to have a bloody nose.
Aspergillosis is a lung fungal infection caused by inhaling aspergillus spores. These types of spores are found in the environment and frequently occur in airborne dust, making them unavoidable. Aspergillosis is an opportunistic fungus and can cause aspergillomas (clumps of fungus) in the lungs. Although aspergillosis mainly affects the lungs and sinuses, it can spread to other organs.
Fungus in the lung and bronchi can cause tissue damage and symptoms include shortness breath upon exertion, difficulty inhaling or breathing air into the lungs, and breathing difficulty at high altitude or altitude sickness. Toxins due to infections by fungi and bacteria which have thick cell walls in the lungs and respiratory tract can cause symptoms of dry cough, chest discomfort, progressive dyspnea particularly on exertion, wheezing, tachycardia, tachypnea, focal pulmonary consolidation with reduced lung expansion and/or clasped lung. Chronic severe lung fungal infections can cause lung inflammation and lead to the development of pulmonary fibrosis.
Valley fever:
Valley fever is an infection caused by the fungus found in soil in the southwestern United States. If the soil is disturbed, microscopic fungal spores can enter the air and when inhaled can cause symptoms similar to the flu. It can affect people of any age but most commonly in those over 60 years old. Individuals can have symptoms for a few weeks to a few months but if the infection becomes more severe, entering other organs, than they can last a lot longer.
Candida Die-Off:
Following a candidiasis, or yeast infection treatment, patients may experience die-off symptoms which include flu-like symptoms, sore throat, fever, hives, headaches, stomach pain, muscle pain and swollen lymph nodes. The die-off symptoms may vary from person to person. Patients may also feel their symptoms of a yeast infection temporarily worsen with increased itching, burning, or pain. The die-off symptoms are caused by a cytokine release and inflammation triggered by the harmful substances such as endotoxins and proteins released when the yeast dies, and/or other types of microbial overgrowth or a different type of infection getting worse when the candida has been cleared. The die-off symptoms are also called Jarisch-Herxheimer phenomenon, or a Herx reaction.