Oral Candidiasis
Oral Candidiasis / Candidosis is the most common oral fungal infection in man especially in early and later life.  In
the general population, carriage rates have been reported to range from 20% - 75% without any symptoms.  It is
usually caused by

Candida is a yeast, which is an obligate organism in humans and a normal constituent of the digestive and vaginal
tracts.  It generally causes no problems in healthy people.

There are a number of different types of oro-pharyngeal candidiasis including acute pseudomembranous, acute

Oral Candidiasis Clinical Spectrum

The oral lesions of Candidiasis have a different appearance and occur in several clinical forms.  A patient can have
several different presentations of
Oral Candida at the same time.  For example, denture stomatitis at the same
time as
angular cheilitis.

Traditionally, these have been based on clinical, mycological, histological, serological & therapeutic criteria.

This classification divides
Oral Candidiasis into acute and chronic types with further sub-dvisions.


  • Acute Pseudomembranous Oral Candidiasis (Thrush)
  • Acute Atrophic Oral Candidiasis (Erythematous)


Chronic Hyperplastic Candidiasis was further subdivided into 4 groups based on localisation pattern & endocrine
(hormonal) involvement as follows:

Chronic Oral Candidosis (Candidal Leukoplakia)
Candidiasis Endocrinopathy Syndrome
Chronic Localized Mucocutaneous Candidiasis
4. Chronic Diffuse Candidosis

A newer classification categorises Candidiasis into:
Predisposing Factors
Acute Pseudo-Membranous Oral Candidiasis (Thrush)

What is Acute Pseudo-Membranous Oral Candidiasis (Thrush)?

Thrush or acute pseudo-membranous candidosis occurs in 5 per cent of newborn infants and in 10 per cent of
elderly debilitated individuals and is one of the earliest and sometimes the initial manifestations of AIDS.
What are the signs & symptoms?

Clinically, appears as creamy white or yellowish plaques that are fairly adherent to oral mucosa.  The lesions vary
from small discrete areas to confluent white patches covering a wide area and the coating is easily rubbed off to
leave a red and slightly bleeding surface.

How is it Diagnosed?

The diagnosis of Thrush is usually clinical & straightforward.  Candida can be confirmed with by the clinical
appearance and by culture of
Candida from the saliva (using a swab or oral rinse).

What are the causes of Acute Pseudo-Membranous Oral Candidiasis (Thrush)?

Predisposing factors for Thrush include changes in local / systemic oral immunity.  Thrush is commonly associated
with antibiotic or steroid use or
xerostomia (dry mouth).  If these local factors can not be identified, systemic
factors must be suspected.

Thrush is, importantly, “a disease of the diseased”, seen mainly in immuno-compromised patients.  This
decreased immunity can stem from
immuno-suppressive drugs, HIV infection, leukæmia or other malignancies.

How is it treated?

Possible predisposing factors should be looked for and if possible, dealt with.

Antifungal medications (both topical & systemic) can be given.

Acute Atrophic Oral Candidiasis / Erythematous Candidiasis (Antibiotic / Steroid-Induced Stomatitis)

What is Acute Atrophic Oral Candidiasis (Antibiotic / Steroid-Induced Stomatitis)?

What are the signs & symptoms?

Clinically, there is widespread erythema (redness) and soreness of the oral mucosa.  This can be concomitant with

The tongue is most often affected, although any area of the oral mucous membrane is susceptible.  Lesions on the
dorsum of the tongue present as depapillated areas.

Red areas often are seen on the palate of individuals with
HIV infection.

The clinical course may be
acute or chronic.

Patients may complain of tenderness, burning, and
dysphagia, especially if oro-pharyngeal candidiasis is
associated with
œsophageal infections.

How is it Diagnosed?

The diagnosis is usually clinical.  If the ætiology is unclear, culture of Candida from the saliva (using a swab or oral
rinse), a smear for fungal
hyphæ or a blood test may be helpful management.
Photos of Acute Pseudo-Membranous Oral Candidiasis (Thrush)
Candida species are opportunistic pathogens, which may cause disease mostly when there are changes in oral
ecology or when the host defenses have been compromised, hence the epithet “candidosis
is the disease of the

Overgrowth of
Candida, however, can lead to local discomfort, altered taste sensation, dysphagia (pain on
swallowing) from œsophageal overgrowth resulting in poor nutrition, slow recovery & prolonged hospital stay.  In
immuno-compromised patients, infection can spread through the bloodstream or upper gastro-intestinal tract
leading to severe infection with significant morbidity and mortality.

candidiasis carries a mortality rate of 71 - 79%.
Images of Candida albicans (hyphae & spores)
Photos of Acute Atrophic Oral Candidiasis / Erythematous Candidiasis
(Antibiotic / Steroid-Induced Stomatitis)
Acute oral candidiasis may complicate steroid / antibiotic therapy particularly with long-term, broad spectrum
such as tetracycline.

It may arise as a consequence of persistent
acute pseudo-membranous candidosis, when pseudo-membranes are
shed, may develop
de novo, or, in HIV infection, may precede pseudo-membranous candidosis.  It is the most
common variant of
candidosis seen in HIV disease.

How is it treated?

Cessation of treatment with the offending antibiotic / steroid medication usually leads to spontaneous resolution,
however this may not be possible and topical anti-fungals may be necessary prophylactically if the causative
therapy is to be continued.  Systemic anti-fungals may be indicated.

Patients using inhaled steroid prescriptions should be advised to rinse their mouth after inhalation to ensure speedy
resolution of
erythematous candidosis.  Moreover, routine oral rinsing after inhalation should be suggested as a
preventive measure to all people using inhaled steroid prescriptions.

Chronic Hyperplastic Oral Candidiasis (Candidal Leukoplakia)

Chronic Atrophic Oral Candidiasis (Denture Sore Mouth & Angular Cheilitis)
Useful Articles:

Crit Rev Oral Biol Med 2000.  Oral Candidal Infections & Anti-Mycotics

Dental Update 2000.  Antimycotic Agents in Oral Candidosis. An Overview. 2.Treatment of Oral Candidosis

Dental Update 2001. Oral Candidosis

Postgrad Med J 2002.  Oral Candidiasis

BDJ 2004.  Patterns of Antifungal Prescribing in General Dental Practice

Aust Dent J 2005.  Oral Candidosis & the Therapeutic Use of Antifungal Agents in Dentistry

Int J Pharmacy & Pharmaceutical Sciences 2010.  Oral Candidiasis - A Review

J Oral Microbiol 2011.  Pathogenesis & Treatment of Oral Candidosis

J Marmara Uni Inst Health Sci 2011.  Oral Candidosis.  Aetiology, Clinical Manifestations, Diagnosis & Management

Patient.co.uk 2014.  Candidiasis

Biomed Sci & Tech Res 2018.  Candidiasis - The Most Common Fungal Infection of Oral Cavity

Useful Websites:

New Zealand Dermatological Society

Patient UK


GP Notebook

National Center for Emergency Medicine Informatics

NHS Choices


Journal of Oral Microbiology
Treatment of Oral Candidiasis