Common Dental and Oral Mucosal Disorders - Topic 3: Candidiasis


3.1   Introduction

There are three mucosal conditions you will commonly encounter in practice. These three entities are commonly called thrush, fever blisters, and canker sores. This topic will cover candidiasis, or thrush.



3.2   Candidiasis

Oral candida infections are not uncommon. For example, in babies, you often see what is commonly known as thrush. In adults, you sometimes see oral candida infections after antibiotic use in patients who use inhaled steroids for asthma and do not rinse with water after use, or in patients who are immunosuppressed.

A good proportion of the population harbors candida organisms in their mouth: 60% of normal individuals, and up to 75% of people with removable dentures. Most patients are asymptomatic, and the oral mucosa appears normal. In this situation we consider those fungal organisms “normal oral flora.” Problems arise when there is a change in oral homeostasis—the normal balance of protective mechanisms and resident oral flora that maintain the health of the oral cavity—so that defense mechanisms are compromised and the number of yeasts and spores increase significantly. Candida albicans is the most frequently isolated species that causes trouble, but others may as well.

Candidiasis often causes symptoms of burning and soreness as well as sensitivity to acidic and spicy foods. Patients may complain of a foul taste in the mouth, but it can also be asymptomatic.



3.3   Candidiasis

There are multiple clinical presentations of candidiasis in the mouth. They are all caused by the same dimorphic organisms. The rod-like structures are hyphae, and the round-ovoid ones are yeast. The hyphae branch periodically. They both can be seen under a microscope.



3.4   Causes of Candidiasis

Under certain circumstances fungal organisms can overgrow to cause disease. A primary disruption in homeostasis occurs with the use of antibiotics or corticosteroids, which markedly change the composition of the oral flora. Deficiencies in the immune and endocrine systems are also important. The diagnosis of candidiasis in an otherwise seemingly healthy young adult may be the first sign of HIV infection. Other causes of candidiasis include cancer chemotherapy, xerostomia resulting from radiation to the head and neck, medications, chronic mucosal irritation, certain blood diseases, and other systemic conditions. Once again, tobacco use has been identified as a cofactor.



3.5   Variants of Candidiasis

There are many clinical variants of the infection. Pseudomembranous candidiasis is the most common. You will observe a white pseudo-membrane that rubs off easily with a gauze or a tongue blade, leaving a red and sometimes bleeding mucosa.

The erythematous variant has no white component, with areas of red-looking tissue that are quite sensitive in most patients. If the erythematous variant is present on the dorsum of the tongue, we call it median rhomboid glossitis. In the past people believed it was a developmental defect, but it is caused by candidiasis. The most common form of oral candidiasis is denture-associated or “denture stomatitis.” It occurs when tissues are traumatized by continued wearing of ill-fitting or inadequately cleaned dental appliances and presents as chronic erythematous candidiasis.

Angular cheilitis involves the corners of the mouth, and also usually involves the skin.

Other variants exist, such as chronic multifocal, mucocutaneous, and others, but are beyond the scope of this module.



3.6   Variants of Candidiasis: Pseudomembranous

Pseudomembranous candidiasis can be associated with recent use of broad-spectrum antibiotics or steroids. White curds of fungal colonies sit on the mucosal surface. The symptoms are variable, but a burning sensation is frequently the main term used by the patient to describe the situation.



3.7   Variants of Candidiasis: Pseudomembranous

Pseudomembranous candidiasis is distinguished clinically by white curds that can be wiped off lightly with gauze.



3.8   Variants of Candidiasis: Pseudomembranous

This is the same patient after a few days of antifungal treatment. Note the erythema is gone, and the tissues look normal. This patient wore a prosthesis and was advised to brush the appliance daily and use an over the counter effervescent tablet each day to keep it clean, and during the antifungal treatment, to soak it in nystatin solution daily.



3.9   Variants of Candidiasis: Erythematous

Erythematous candidiasis is also a common condition. It is a bit more difficult to diagnose, since you do not see the white pseudomembrane. It may or may not have areas of pin-point bleeding. In most cases the mucosa looks atrophic and it is tender to palpation.

It may manifest clinically as a red patch on the dorsum of the tongue, known as median rhomboid glossitis, under a denture, which is termed denture stomatitis or erythematous candidiasis, or in the corners of the mouth, angular cheilitis.



3.10   Variants of Candidiasis: Erythematous

Candida manifests as central erosion of the tongue. This case is erythematous, as compared to the previous example.



3.11   Variants of Candidiasis: Erythematous

Here are other examples of median rhomboid glossitis, erythematous type.



3.12   Variants of Candidiasis: Erythematous

This patient does not wear a denture. This is more common in severely immunosuppressed patients.



3.13   Variants of Candidiasis: Erythematous

Here is another example of erythematous candidiasis of the hard palate.



3.14   Variants of Candidiasis: Erythematous

Here is another example of erythematous candidiasis of the hard palate.



3.15   Variants of Candidiasis: Erythematous

Here is another example of erythematous candidiasis of the hard palate.



3.16   Variants of Candidiasis:Angular Cheilitis

Angular Cheilitis is also known as “perleche.” Cheilitis is characterized by erythema and scaling of the lips. When called “angular,” it refers to the corners of the lips (commissures of the mouth). Saliva pools in these areas. The most common cause of angular cheilitis is candida. Another term is perioral cheilocandidiasis.



3.17   Variants of Candidiasis:Angular Cheilitis

Note the cracking at the corners of the mouth. Angular cheilitis is more common in patients who wear dentures of appliances. Causes other than candida include chronic lip licking, sun exposure and sodium lauryth sulfate preservative in some toothpastes.



3.18   Variants of Candidiasis: Angular Cheilitis

Angular cheilitis that completely disappeared after treatment with nystatin ointment for 2 weeks.



3.19   Treatment of Candidiasis

Both topical and systemic medications are used to treat candidiasis. Fluconazole and Clotrimazole are recommended.