Doctor's Notes on Oral Thrush
Thrush is the name given to a yeast infection of the mouth or throat, most often caused by Candida yeast. Thrush can be linked to yeast infection of the esophagus as well and is sometimes referred to as oral candidiasis. Thrush is more common in people with some degree of immune system suppression than in those with healthy immune systems.
The characteristic symptom of thrush is a raised, creamy, white, curd-like coating that can be seen on the tongue, insides of the cheeks, tonsils, gums, roof of the mouth, or back of the throat. Possible associated symptoms can include pain, redness, burning, loss of taste sensation, mild bleeding, or discomfort. Another symptom can be abnormal sensation in the mouth, such as a “cotton-like” feeling. This can cause pain with swallowing and refusal to eat in young children.
Oral Thrush Symptoms
Oral thrush is characterized by a thick white coating of the tongue, inner cheeks, inner lip region, or gums. This coating may be differentiated from the very common off-white discoloration of the tongue associated with breast milk or infant formula debris by several means: (1) an oral Candida infection is a very bright white color -- milk debris is an off-white color; (2) oral Candida infections may also involve the buccal surface, inner lip area, and gingiva, while milk debris is limited to the tongue; and (3) oral Candida is rather adherent to an involved skin surface while milk debris may more easily be wiped off with a damp facecloth. Neither thrush nor milk debris cause discomfort nor other symptoms when limited to the mouth.
Maternal nipple/areola candidiasis commonly causes signs and symptoms like redness and tenderness of the involved area. The rash associated with Candida diaper dermatitis is generally not as bothersome as the more common diaper rash associated with irritation from excessive stool and urine contact with the infant's skin.
Oral Thrush Causes
Thrush is caused by an overgrowth of the yeast Candida albicans, which is commonly found on skin surfaces, the oral cavity, and throughout the intestinal tract of healthy individuals. Newborn infants often are exposed to the fungus during vaginal delivery and may develop oral evidence of thrush within 10 days post-delivery. Breastfeeding infants may infect their mother's nipple area during breastfeeding. In addition, a Candida overgrowth in the stool may be associated with a characteristic diaper rash. Contamination of formula bottle nipples and pacifiers with the Candida fungus may also introduce the yeast into a child's oral cavity.
In older children and adults, oropharyngeal candidiasis is associated with several risk behaviors, including prolonged or repeated use of oral antibiotics, prednisone (or other steroid medications), smoking, dentures, use of birth control pills, and medical conditions especially diabetes (either type I or type II) or any diseases that can suppress your immune system (HIV/AIDS). Perhaps the most common association for developing thrush is improper technique during the use of inhalers containing corticosteroids for the control of asthma or COPD (chronic obstructive pulmonary disease). Such medications require rinsing your mouth with water and then spitting out the water to eliminate any non-inhaled medication. Patients using a metered-dose inhaler (MDI) for administration of their steroids are recommended to use a "spacer" to lessen the amount of potential residual steroid left in the mouth. Those individuals with the above risk factors may also develop Candida overgrowth of the esophagus. To confirm such a diagnosis requires an endoscopy. A gastroenterologist (GI doctor) performs this study. During the procedure, the doctor passes a flexible tube with a camera at the end from the mouth to the esophagus to the entry point into the stomach.
There are so many childhood diseases, infectious and noninfectious, that it would be impossible to list them all here. However, we will introduce some of the most common ones, including viral and bacterial infections as well as allergic and immunologic illnesses.
Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.