Oral infections may play a role in the development of cardiovascular and respiratory diseases. Medical student Maria Angela Grima takes a look at the causes and symptoms of oral candidiasis and identifies who is most at risk.
Maintaining oral health is more important than we may realise. Apart from our teeth, attention must also be paid to our gums, tongue and all the other tissues lying inside the mouth. Ongoing research suggests that chronic oral infections may play a role in the development of cardiovascular and respiratory diseases, particularly diabetes, stroke, heart attacks and bacterial chest infections.
The mouth normally contains several harmless microorganisms, and any disruption of this normal ‘flora’ may result in infection. Individuals with a defective immune system are also more susceptible to infection.
Oral candidiasis (oral thrush) is a fungal infection of the mouth or throat caused by candida. It is estimated that more than 50 per cent of humans carry this fungus in their oral cavity but infection will only occur if there is imbalance in the oral microbiological environment or immunity.
Recognising the symptoms
Oral thrush commonly appears as a white, velvety patch (plaque) or white spots on the inside of the mouth and on the tongue. Once scraped off, this plaque usually reveals underlying red mucosa that may bleed.
The plaque can extend up to the throat, causing difficulty in swallowing. It can also result in a painful burning sensation on the tongue, together with an unpleasant, salty or bitter taste.
Candidal infection may occur due to a defective immune system
White plaques which cannot be scraped off do not suggest oral thrush. Other diagnoses must be kept in mind, and it is important to have them checked by a doctor.
Thrush may also present itself with red, sore areas inside or at the corners of the mouth.
Who is at risk?
Oral thrush is often seen at the extremes of age: infants, children and the elderly.
Treating babies with antibiotics can alter the microorganisms found in the mouth, making them more susceptible to candidal infection. This also applies if a breastfeeding mother is on antibiotics, or if there is inadequate cleansing of bottle-feeding equipment. Often, infection simply occurs because of a premature immune system, especially in preterm infants.
Babies with sore plaques may show a decreased interest to feed or may draw back from feeding. Alternatively, they may not be bothered by the plaques at all. A milk-coated tongue may be confused with oral candidiasis. If the plaques can be rubbed off easily, it is probably milk rather than thrush.
Maintaining good hygiene
Dummies, bottles, teats or pacifiers must be sterilised regularly before every feed
Individuals on inhaled corticosteroids, especially younger adults or the elderly, are also at risk. While causing fewer systemic side effects than their oral equivalents, these inhaled medications can alter the acidity in the mouth, leading to bacterial imbalance and oral candidiasis.
Other predisposing factors include drugs that reduce the quantity or quality of saliva in the mouth, injury to the mouth, ill-fitting or poorly cleansed dentures and smoking.
Candidal infection may also occur due to a defective immune system. Diabetes mellitus is one such situation – the presence of high-blood glucose levels in uncontrolled diabetes not only compromises immunity but also promotes proliferation of the fungus.
Candidiasis is in fact relatively common in diabetics, possibly even before a diagnosis of diabetes is made. Once diagnosed with thrush, one should attend his family physician and have his blood glucose levels checked.
Symptoms which suggest the presence of diabetes include thirst, frequent urination, blurred vision, impotence, as well as numbness and tingling in the feet.
Other causes of immunosuppression include the use of long courses or high doses of antibiotics, chemotherapy and radiotherapy, haematological cancers, genetic immunodeficiencies, and also infections such as HIV.
Treatment
In most cases, the general practitioner will be able to diagnose oral candidiasis by examining the oral cavity. Moreover, he could assess whether there is underlying diabetes or any other immunodeficiency state. The physician will prescribe a course of anti-fungal medicine – available in the form of gels, lozenges, tablets, creams or mouth rinses – to be taken over one to two weeks.
Rinsing the mouth after meals helps keep infections at bay.Prevention
Good oral hygiene will prevent candidiasis. This can be achieved through rinsing the mouth after meals, brushing the teeth twice daily with a fluoride-containing toothpaste, flossing, and changing toothbrush at least every three months.
Dentures must be removed every night to be brushed with warm water and soap, then left to soak in sterilised liquid for the night. The dentist will correct an ill-fitting denture to reduce soreness and infection rate.
Similar precautions should also be taken in infants. Dummies, bottles, teats or pacifiers must be sterilised regularly before every feed. A soft washcloth soaked in warm water can be used to wipe the tongue, palate, gums and inside of the cheeks gently after feeding.
Breastfeeding mothers with nipple thrush must treat them-selves appropriately with anti-fungal creams while continuing to breastfeed.
Persons taking inhaled corticosteroids must use a spacer to deliver the medication. This is specifically intended to maximise the amount of drug reaching the lungs, hence reducing contact with the mouth. The mouth must also be rinsed thoroughly with water afterwards.
These measures should be complemented by a healthy diet, good diabetic control and smoking cessation.
This article was reviewed by Dr James Gauci, medicine specialist trainee.