Causes of oral thrush
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Oral Thrush Causes: Candida albicans and Other Yeasts
Oral thrush, also known as oral candidiasis, is primarily caused by the overgrowth of the yeast Candida albicans in the mouth. While C. albicans is the most common culprit, other Candida species can also be involved in some cases Kate2021Wilson2021Karajacob2021+5 MORE.
Risk Factors and Triggers for Oral Thrush
Immune System Suppression
A weakened immune system is a major risk factor for developing oral thrush. This includes people with HIV/AIDS, those undergoing chemotherapy or radiotherapy, and the elderly or infants whose immune systems are not fully developed Kate2021Wilson2021Karajacob2021+4 MORE.
Antibiotic and Corticosteroid Use
The use of antibiotics can disrupt the normal balance of microorganisms in the mouth, allowing Candida to overgrow. Similarly, inhaled corticosteroids (often used for asthma) can increase the risk, especially if proper oral hygiene is not maintained after use Kate2021Wilson2021Minh2023.
Chronic Diseases and Hospitalization
People with chronic diseases such as diabetes, chronic obstructive pulmonary disease, and those who are hospitalized are at higher risk. Hospitalized patients, especially those with poor self-care or who are underweight, are more likely to develop oral thrush Kate2021Minh2023.
Poor Oral Hygiene and Dentures
Wearing dentures, especially if they are not cleaned properly, and poor oral hygiene can create an environment where Candida thrives Kate2021Wilson2021Minh2023.
Dry Mouth and Other Contributing Factors
A dry mouth (low saliva pH), smoking, and certain medical devices (like IUDs) can also contribute to the development of oral thrush Kate2021Minh2023.
Age-Related Susceptibility
Infants and young children are particularly susceptible to oral thrush, as are older adults Kate2021Wilson2021R.Venkatajothi2017+1 MORE. Studies show higher infection rates in children under 8 years old and in infants aged 1-2 months R.Venkatajothi2017Habib2007.
Transmission and Other Routes
Oral thrush can sometimes be transmitted through direct contact, such as during unprotected oral sex, especially if one partner already has a yeast infection .
Imbalance in Normal Oral Flora
Candida is normally present in the mouth as part of the healthy flora. When the balance of these microorganisms is disturbed—due to any of the above factors—Candida can multiply and cause infection Vila2020Bansal202210.
Conclusion
Oral thrush is caused by the overgrowth of Candida, most often C. albicans, in the mouth. The main causes and risk factors include immune suppression, antibiotic or corticosteroid use, chronic diseases, poor oral hygiene, dentures, dry mouth, age extremes, and sometimes direct transmission. Maintaining good oral hygiene and addressing underlying risk factors are key to prevention and management Kate2021Wilson2021Karajacob2021+6 MORE.
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