What is Oral Candidiasis?
Oral candidiasis is an infection in the mouth caused by a type of yeast known as Candida albicans. This condition was first identified in 1838 by a children’s doctor named Francois Veilleux. People usually get this infection if their immune system, the body’s defense against disease, is weakened. This weakness could be local (only in a certain area) or systemic (throughout the body). It commonly occurs in newborns and the elderly, people with diseases that compromise the immune system like HIV/AIDS, and those who take long-term steroid and antibiotic drugs. Even some asthma and chronic lung disease medications, like inhaled corticosteroids, can weaken the mouth’s immune defenses.
While thrush, or acute pseudomembranous candidiasis, is the most common form of oral candidiasis, there are many other types that can show up as either white or red sores. White sores can indicate conditions like acute pseudomembranous candidiasis and chronic hyperplastic candidiasis, while red sores may point to acute and chronic erythematous candidiasis, angular cheilitis, median rhomboid glossitis, and linear gingival erythema. Some uncommon oral types like cheilocandidiasis, chronic mucocutaneous candidiasis, and chronic multifocal candidiasis fall outside of these categories, but they are outside the scope of this discussion.
Doctors can typically identify oral candidiasis through a physical examination, reviewing the patient’s medical history, and evaluating their risk factors. In some cases, a biopsy, or small tissue sample, might be recommended in addition to treatment based on educated guesses. A culture, or laboratory study of the infection, may be performed if the antifungal treatment doesn’t work as expected. Usually, mild cases of oral candidiasis can be cleared up with topical antifungal therapy and good oral hygiene. For patients who don’t respond to topical treatment, can’t tolerate it, or are at a higher risk of developing a system-wide infection, a full-body or systemic antifungal therapy is often prescribed.
What Causes Oral Candidiasis?
Oral candidiasis, or a fungal infection in the mouth, is primarily caused by the species Candida albicans, which can be found in more than 80% of cases. Candida albicans is a unique type of yeast that can appear in different forms depending on its surroundings.
Less frequently, other species like Candida glabrata, Candida tropicalis, Candida kruesi, Candida guillermondii, Candida lusitaniae, Candida parapsilosis, Candida pseudotropicalis, and Candida stellatoidea can also be responsible for causing oral candidiasis. These non-albicans Candida species tend to be more common in people aged 80 and above compared to their younger counterparts.
Interestingly, Candida is typically found in the mouths of healthy individuals. In fact, 30% to 60% of adults and 45% to 65% of infants have Candida in their mouths. However, it usually coexists peacefully and does not cause any harm.
However, certain factors can cause this harmless Candida to become a problem. These include malnutrition, being very young or old, metabolic diseases, conditions that weaken the immune system, other infections, getting radiation therapy, having an organ transplant, long-term steroid use, antibiotic treatment, and reduced salivary gland function.
Risk Factors and Frequency for Oral Candidiasis
Oral candidiasis, an infection in the mouth, can affect anyone but is especially common in those who have a weakened immune system. For example, more than 90% of people with HIV will experience this infection at some point during their illness.
This infection isn’t biased; it impacts males and females equally. It mostly happens in newborns and infants, rarely in the first week after birth, but most frequently during the fourth week. Once a baby is older than six months, oral candidiasis is less common, probably because their immune system is starting to protect them better. For these patients, signs of a weakened immune system, that may be causing the infection, include diarrhea, rashes, frequent infections, and an enlarged liver and spleen.
- Oral candidiasis can happen in anyone but is most common in those with weakened immune systems.
- More than 90% of individuals with HIV will develop this infection at some point.
- The condition affects both males and females equally.
- It primarily appears in newborns and infants, especially during their fourth week of life.
- The occurrence decreases in babies over six months old, likely due to improved immunity.
- Warning signs of a weakened immune system, which can lead to oral candidiasis, include diarrhea, rashes, frequent infections, and an enlarged liver and spleen.
Signs and Symptoms of Oral Candidiasis
Oral thrush, also known as pseudomembranous candidiasis, is a common type of oral yeast infection or candidiasis. Several kinds of oral candidiasis exist. They can generally appear as white or reddish (erythematous) spots in the mouth.
- Pseudomembranous candidiasis, or oral thrush, is the most common form and is seen in newborns, elderly, and those with weakened immune systems. It’s characterized by white patches that can be cleared with a cloth, to expose a red area. If symptoms are felt, they may include a burning sensation, bleeding, and taste changes.
- Hyperplastic candidiasis presents as slightly raised white spots or plaques that cannot be wiped off. These are commonly found on the cheeks inside the mouth. There seems to be a link between smoking and this condition, and it can develop into severe tissue abnormalities.
- Acute atrophic candidiasis is often seen after antibiotic treatment and exhibits as a reddish area in the mouth, often on the palate or the upper surface of the tongue. Patients may feel a burning sensation and tongue discomfort.
- Chronic atrophic candidiasis, or denture stomatitis, is an inflammation found under dentures, and it’s usually red and swollen. This situation is often asymptomatic but can cause a sore mouth or burning sensation.
- Median rhomboid glossitis is a rare variety presenting as a reddish patch in the middle of the top surface of the tongue. Smoking and inhaled steroids are linked to its development.
- Angular cheilitis exhibits as red, sore patches in the corners of the mouth. Various factors contribute to this condition, including wearing dentures, lip licking, and nutrient deficiencies.
- Linear gingival erythema appears as a red line or band over tooth gums. This condition is generally found in HIV patients, but it may also develop in healthy children.
Testing for Oral Candidiasis
Oral candidiasis, also known as oral thrush, is often diagnosed based on a thorough health checkup, considering your medical history, and evaluation of risk factors. This process involves identifying specific signs of the infection, ruling out other conditions, and observing how effectively your symptoms improve with anti-fungal treatment.
Oral thrush may sometimes resemble very early-stage or even more serious diseases such as cancer; therefore, taking a biopsy or small tissue sample is strongly recommended alongside the usual treatment.
If the anti-fungal treatment isn’t successful, the next step is to conduct cultures and sensitivity tests. These tests help identify the specific type of Candida (the yeast causing oral thrush) and determine the most effective treatment. Various methods are available to collect a sample from your mouth. The method chosen largely depends on what the doctor observes during a clinical examination.
If there are visible lesions or sores, the doctor might take a sample using a plain microbial swab or a sterile foam pad. If no specific sores are identified, but a Candida infection is suspected, a whole saliva sample might be collected in a sterile container, or the doctor might ask you to rinse your mouth with a special solution to collect the sample.
If the doctor suspects denture stomatitis (inflammation of the mouth caused by denture use), samples might be collected from both the inner surface of the denture as well as the inside lining of the mouth, as only testing the mouth might not detect the infection.
Along with confirming oral thrush, testing for underlying diseases that reduce the body’s immunity should also be considered. This is important because such conditions might be the reason for getting oral thrush. People might be tested for diseases like HIV, adrenal insufficiency (where the adrenal glands don’t produce enough hormones), malnutrition, steroid use, and diabetes.
Treatment Options for Oral Candidiasis
The treatment for an infection caused by Candida, a type of fungus, often depends on the severity of the infection and how well the patient’s immune system is functioning. Topical antifungal medication, which is applied directly to the affected area, is usually effective for mild cases of oral thrush, a type of oral candidiasis. If oral thrush isn’t responding to topical treatment, or if the patient is at risk of the infection spreading in the body, a doctor might recommend a drug taken by mouth or through a vein.
Some common topical antifungal drugs that might be used to treat oral thrush include nystatin, miconazole, clotrimazole, and ketoconazole. Flavored nystatin mouth rinse is often used to treat oral candidiasis. However, the patient might experience side effects such as nauseousness, vomiting, or diarrhea.
Nystatin and clotrimazole contain a lot of sugar, so if you have diabetes or are at risk of tooth decay, your doctor might recommend a triazole medication, such as fluconazole or itraconazole.
If oral candidiasis is severe or doesn’t respond to treatment, doctors might recommend stronger medications. For example, fluconazole is often used for moderate to severe cases. If the infection doesn’t respond to fluconazole, other medications might be considered.
Pregnant women should avoid oral azoles, a type of antifungal medication, during the first trimester of pregnancy. Other treatment options include clotrimazole, nystatin, and miconazole.
For children being treated for this condition, the dose of medication will need to be adjusted based upon their weight.
Patients should also be advised to control conditions that can weaken their immune system, like uncontrolled diabetes, smoking, and malnutrition.
Denture hygiene plays a key role in treating types of oral candidiasis associated with dentures, such as denture stomatitis. Regularly cleaning and disinfecting dentures and leaving them out overnight can help eliminate fungus from the dentures.
There are specific considerations for different types of candidiasis. For example, breastfed infants with acute pseudomembranous candidiasis can be treated with topical antifungals, and their mothers may need oral antifungals if their nipples show symptoms of infection.
Generally, if angular cheilitis (sores at the corners of the mouth) is present, the treatment usually includes an antifungal cream and steroid creams.
Chronic hyperplastic candidiasis, a type of yeast infection that often affects the skin and mucus membranes, is typically treated with fluconazole and quitting smoking. Linear gingival erythema, a candida-induced skin condition often associated with HIV infection, includes debridement (removal of affected tissue), use of a chlorhexidine mouthwash in addition to antifungal therapy, and ensuring the individual is receiving appropriate antiretroviral treatment.
What else can Oral Candidiasis be?
When a doctor is trying to diagnose red types of oral thrush (a type of yeast infection), they must consider other similar conditions such as:
- Oral mucositis (inflammation of mucous membranes in the mouth)
- Erythroplakia (red patches in the mouth that can’t be scrubbed off)
- Thermal burns
- Erythema migrans (Lyme disease)
- Anemia
Chronic thick white type of oral thrush can be mistaken with:
- Leukoplakia (white patches in the mouth)
- Lichen planus (an inflammatory condition that affects the mouth)
- Pemphigoid and pemphigus (rare skin blistering disorders)
- Oral squamous cell carcinoma (a type of oral cancer)
Other conditions that might be mistaken for oral thrush include:
- Oral hairy leukoplakia (white patches caused by the Ebstein-Barr virus)
- Angioedema (swelling under the skin)
- Aphthous stomatitis (canker sores)
- Herpes gingivostomatitis and herpes labialis (types of herpes infections in the mouth and lips)
- Measles (Koplik spots are a symptom)
- Perioral dermatitis (a rash around the mouth)
- Steven-Johnsons syndrome (a serious disorder of the skin and mucous membranes)
- Histiocytosis (a group of diseases that involve an abnormal increase in white blood cells)
- Blastomycosis (a fungal infection)
- Lymphohistiocytosis (a severe disorder affecting immune system function)
- Diphtheria (a serious bacterial throat infection)
- Esophagitis (inflammation of the esophagus)
- Syphilis (a sexually transmitted bacterial infection)
- Streptococcal pharyngitis (strep throat)
What to expect with Oral Candidiasis
The outlook for individuals with oral thrush (oral candidiasis) is generally positive when they receive the right treatment. If the condition reoccurs, it’s usually because the patient has not consistently followed their treatment plan, they haven’t appropriately cleaned or taken out their dentures or any underlying issues that make it easier for them to get infected have not been resolved.
Possible Complications When Diagnosed with Oral Candidiasis
Oral candidiasis, or a yeast infection in the mouth, can sometimes spread to the throat in even healthy individuals. This may cause difficulty swallowing and breathing difficulties. However, this condition also poses a significant risk to people with weakened immune systems, as it can spread throughout the body. Candidal esophagitis, a yeast infection in the esophagus, is particularly common in people living with HIV/AIDS.
Common Symptoms:
- Difficulty swallowing
- Respiratory distress
- Disease spreading throughout the body (in those with weakened immune systems)
- Candidal esophagitis (yeast infection in the esophagus), especially in people with HIV/AIDS
Preventing Oral Candidiasis
People with a condition called oral candidiasis, a mouth infection caused by a type of fungus called Candida, need advice on how to prevent this disease from spreading further. They also need to understand how important it is to find and treat any conditions that might be weakening their immune system, which is the body’s defense against infections and other diseases.
For those who use steroid inhalers, it’s advised that they rinse their mouth with water after each use. This can help to prevent oral candidiasis.
Oral candidiasis can also be connected to poor nutrition, lack of iron, and vitamin deficiencies. It’s important for these individuals to have the right advice on healthy eating.
Good dental hygiene, such as regular tooth brushing and proper care of dentures, can help prevent oral candidiasis. Dental experts can give the right advice on this.
Finally, high sugar in the diet can help the Candida fungus multiply. Therefore, it might be advisable to lower sugar consumption.