|Classification and external resources|
Oral candidiasis (thrush)
|eMedicine||med/264 emerg/76 ped/312 derm/67|
Candidiasis, thrush, or yeast infection is a fungal infection (mycosis) of any species from the genus Candida (one genus of yeasts). Candida albicans is the most common agent of candidiasis in humans. It is also technically known as candidosis, moniliasis, and oidiomycosis.
Candidiasis encompasses infections that range from superficial, such as oral thrush and vaginitis, to systemic and potentially life-threatening diseases. Candida infections of the latter category are also referred to as candidemia or invasive candidiasis, and are usually confined to severely immunocompromised persons, such as cancer, transplant, and AIDS patients, as well as nontrauma emergency surgery patients.
Superficial infections of skin and mucosal membranes by Candida causing local inflammation and discomfort are common. While clearly attributable to the presence of the opportunistic pathogens of the genus Candida, candidiasis describes a number of different disease syndromes that often differ in their causes and outcomes.
Candidiasis may be divided into these types:
- Mucosal candidiasis
- Oral candidiasis (thrush, oropharyngeal candidiasis)
- Pseudomembranous candidiasis
- Erythematous candidiasis
- Hyperplastic candidiasis
- Denture related stomatitis — Candida organisms are involved in about 90% of cases
- Angular stomatitis — Candida species are responsible for about 20% of cases, mixed infection of C. albicans and Staphylococcus aureus for about 60% of cases.
- Median rhomboid glossitis
- Candidal vulvovaginitis (vaginal yeast infection)
- Candidal balanitis, infection of the glans penis, almost exclusively occurring in uncircumcised males.
- Esophageal candidiasis (Candid esophagitis).
- Oral candidiasis (thrush, oropharyngeal candidiasis)
- Cutaneous candidiasis
- Onychomycosis (nail infection) caused by Candida
- Invasive candidiasis
- Antibiotic candidiasis (iatrogenic candidiasis)
Signs and symptoms
Symptoms of candidiasis vary depending on the area affected. Most candidial infections result in minimal complications such as redness, itching, and discomfort, though complications may be severe or even fatal if left untreated in certain populations. In immunocompetent persons, candidiasis is usually a very localized infection of the skin or mucosal membranes, including the oral cavity (thrush), the pharynx or esophagus, the gastrointestinal tract, the urinary bladder, the fingernails or toenails (onychomycosis), and the genitalia (vagina, penis).
Candidiasis is a very common cause of vaginal irritation, or vaginitis, and can also occur on the male genitals. In immunocompromised patients, Candida infections can affect the esophagus with the potential of becoming systemic, causing a much more serious condition, a fungemia called candidemia.
Thrush is commonly seen in infants. It is not considered abnormal in infants unless it lasts longer than a few weeks.
Infection of the vagina or vulva may cause severe itching, burning, soreness, irritation, and a whitish or whitish-gray cottage cheese-like discharge. These symptoms are also present in the more common bacterial vaginosis. In a 2002 study, only 33% of women who were self-treating for a yeast infection actually had a such an infection, while most had either bacterial vaginosis or a mixed-type infection. Symptoms of infection of the male genitalia (balanitis thrush) include red skin around the head of the penis, swelling, irritation, itchiness and soreness of the head of the penis, thick, lumpy discharge under the foreskin, unpleasant odour, difficulty retracting the foreskin (phimosis), and pain when passing urine or during sex.
Candida yeasts are generally present in healthy humans, particularly on the skin, but their growth is normally limited by the human immune system, by competition of other microorganisms, such as bacteria occupying the same locations in the human body, and in the case of skin, by the relative dryness of the skin, as Candida requires moisture for growth.
C. albicans was isolated from the vaginas of 19% of apparently healthy women, i.e., those who experienced few or no symptoms of infection. External use of detergents or douches or internal disturbances (hormonal or physiological) can perturb the normal vaginal flora, consisting of lactic acid bacteria, such as lactobacilli, and result in an overgrowth of Candida cells, causing symptoms of infection, such as local inflammation. Pregnancy and the use of oral contraceptives have been reported as risk factors. Diabetes mellitus and the use of antibacterial antibiotics are also linked to increased rates of yeast infections. Diets high in simple carbohydrates have been found to affect rates of oral candidiases, and hormone replacement therapy and infertility treatments may also be predisposing factors. Wearing wet swimwear for long periods of time is also believed to be a risk factor.
A weakened or undeveloped immune system or metabolic illnesses such as diabetes are significant predisposing factors of candidiasis. Diseases or conditions linked to candidiasis include HIV/AIDS, mononucleosis, cancer treatments, steroids, stress, and nutrient deficiency. Almost 15% of people with weakened immune systems develop a systemic illness caused by Candida species. In extreme cases, these superficial infections of the skin or mucous membranes may enter into the bloodstream and cause systemic Candida infections.
In penile candidiasis, the causes include sexual intercourse with an infected individual, low immunity, antibiotics, and diabetes. Male genital yeast infections are less common, and incidences of infection are only a fraction of those in women; however, yeast infection on the penis from direct contact via sexual intercourse with an infected partner is not uncommon.
Candida species are frequently part of the human body's normal oral and intestinal flora. Treatment with antibiotics can lead to eliminating the yeast's natural competitors for resources, and increase the severity of the condition. In the Western Hemisphere, about 75% of females are affected at some time in their lives.
Diagnosis of a yeast infection is done either via microscopic examination or culturing. For identification by light microscopy, a scraping or swab of the affected area is placed on a microscope slide. A single drop of 10% potassium hydroxide (KOH) solution is then added to the specimen. The KOH dissolves the skin cells, but leaves the Candida cells intact, permitting visualization of pseudohyphae and budding yeast cells typical of many Candida species.
For the culturing method, a sterile swab is rubbed on the infected skin surface. The swab is then streaked on a culture medium. The culture is incubated at 37 °C for several days, to allow development of yeast or bacterial colonies. The characteristics (such as morphology and colour) of the colonies may allow initial diagnosis of the organism causing disease symptoms.
A one-time dose of fluconazole is 90% effective in treating a vaginal yeast infection. Local treatment may include vaginal suppositories or medicated douches. Other types of yeast infections require different dosing. Gentian violet can be used for thrush in breastfeeding babies, but when used in large quantities, it can cause mouth and throat ulcerations, and has been linked to mouth cancer in humans and to cancer in the digestive tract of other animals. C. albicans can develop resistance to fluconazole, this being more of an issue in those with HIV/AIDS who are often treated with multiple courses of fluconazole for recurrent oral infections.
For vaginal yeast infection in pregnancy, topical imidazole or triazole antifungal is considered the therapy of choice owing to available safety data. Systemic absorption of these topical formulations is minimal, posing little risk of transplacental transfer. In vaginal yeast infection in pregnancy, treatment with topical azole antifungals is recommended for 7 days instead of a shorter duration.
Not enough evidence is available to determine if probiotics, either as pills or as yogurt, have an effect on the rate of occurrence of vaginal yeast infections. No benefit has been found for active infections.
Oral candidiasis is the most common form, by far the most common fungal infection of the mouth, and it also represents the most common opportunistic oral infection in humans. Candida septicemia is rare.
Esophageal candidiasis is the most common esophageal infection in persons with AIDS, and accounts for about 50% of all esophageal infections, often coexisting with other esophageal diseases. About two-thirds of people with AIDS and esophageal candidiasis also have oral candidiasis.
The colloquial term "thrush" refers to the resemblance of the white flecks present in some forms of candidiasis (e.g. pseudomembranous candidiasis) with the breast of the bird of the same name. The term candidosis is largely used in British English, and candidiasis in American English. Candida is also pronounced differently, in American English, the stress is on the "i", whereas in British English the stress is on the first syllable.
The genus Candida and species C. albicans were described by botanist Christine Marie Berkhout in her doctoral thesis at the University of Utrecht in 1923. Over the years, the classification of the genera and species has evolved. Obsolete names for this genus include Mycotorula and Torulopsis. The species has also been known in the past as Monilia albicans and Oidium albicans. The current classification is nomen conservandum, which means the name is authorized for use by the International Botanical Congress (IBC).
The genus Candida includes about 150 different species; however, only a few are known to cause human infections. C. albicans is the most significant pathogenic species. Other species pathogenic in humans include C. tropicalis, C. glabrata, C. krusei, C. parapsilosis, C. dubliniensis, and C. lusitaniae.
The name Candida was proposed by Berkhout. It is from the Latin word toga candida, referring to the white toga (robe) worn by candidates for the Senate of the ancient Roman republic. The specific epithet albicans also comes from Latin, albicare meaning "to whiten". These names refer to the generally white appearance of Candida species when cultured.
What has been described as "a large pseudoscientific cult" has developed around the topic of Candida, with claims up to one in three people are affected by conditions with terms such as systemic candidiasis, "candidiasis hypersensitivity", fungal type dysbiosis, Candida-related complex, the yeast syndrome, yeast allergy, yeast overgrowth, or simply "Candida" or "yeast problem". Some practitioners of alternative medicine have promoted these purported conditions and sold dietary supplements as supposed cures; a number of them have been prosecuted.
In 1990, alternative health vendor Nature's Way signed an FTC consent agreement not to misrepresent in advertising any self-diagnostic test concerning yeast conditions or to make any unsubstantiated representation concerning any food or supplement's ability to control yeast conditions, with a fine of $30,000 payable to the National Institutes of Health for research in genuine candidiasis.
- Walsh TJ, Dixon DM (1996). "Deep Mycoses". In Baron S et al. eds. Baron's Medical Microbiology (4th ed.). Univ of Texas Medical Branch. ISBN 0-9631172-1-1.
- MedlinePlus Encyclopedia Vaginal yeast infection
- James, William D.; Berger, Timothy G.; et al. (2006). Andrews' Diseases of the Skin: clinical Dermatology. Saunders Elsevier. pp. 308–311. ISBN 0-7216-2921-0.
- Kourkoumpetis T, Manolakaki D, Velmahos G, Chang Y, Alam HB, De Moya MM, Sailhamer EA, Mylonakis E (2010). "Candida infection and colonization among non-trauma emergency surgery patients". Virulence 1 (5): 359–66. doi:10.4161/viru.1.5.12795. PMID 21178471.
- Fidel PL (2002). "Immunity to Candida". Oral Dis. 8: 69–75. doi:10.1034/j.1601-0825.2002.00015.x. PMID 12164664.
- Pappas PG (2006). "Invasive candidiasis". Infect. Dis. Clin. North Am. 20 (3): 485–506. doi:10.1016/j.idc.2006.07.004. PMID 16984866.
- Nyirjesy P, Sobel JD (May 2013). "Genital mycotic infections in patients with diabetes.". Postgraduate Medicine 125 (3): 33–46. doi:10.3810/pgm.2013.05.2650. PMID 23748505.
- Yamada T, Alpers DH, et al. (2009). Textbook of gastroenterology (5th ed.). Chichester, West Sussex: Blackwell Pub. p. 814. ISBN 978-1-4051-6911-0.
- Nolting S, Brautigam M, Weidinger G (1994). "Terbinafine in onychomycosis with involvement by non-dermatophytic fungi". The British journal of dermatology. 130 Suppl 43: 16–21. doi:10.1111/j.1365-2133.1994.tb06088.x. PMID 8186136.
- Errol Reiss, H. Jean Shadomy, G. Marshall Lyon (2011). "Chapter 11". Fundamental medical mycology. Hoboken, N.J.: John Wiley & Sons. ISBN 978-1-118-10176-6.
- Dolin, [edited by] Gerald L. Mandell, John E. Bennett, Raphael (2010). Mandell, Douglas, and Bennett's principles and practice of infectious diseases (7th ed.). Philadelphia, PA: Churchill Livingstone/Elsevier. pp. Chapter 250. ISBN 978-0-443-06839-3.
- "Thrush". 2011. Retrieved 2011-04-08.
- Terri Warren, RN (2010). "Is It a Yeast Infection?". Retrieved 2011-02-23.
- Ferris DG, Nyirjesy P, Sobel JD, Soper D, Pavletic A, Litaker MS (March 2002). "Over-the-counter antifungal drug misuse associated with patient-diagnosed vulvovaginal candidiasis". Obstetrics and Gynecology 99 (3): 419–425. doi:10.1016/S0029-7844(01)01759-8. PMID 11864668.
- NHS: Symptoms of thrush in men (balanitis thrush)
- Bruce G. Wolff et al., ed. (2007). The ASCRS textbook of colon and rectal surgery. New York: Springer. pp. 241, 242, 245. ISBN 0-387-24846-3.
- Mulley, A. G.; Goroll, A. H. (2006). Primary Care Medicine: office evaluation and management of the adult patient. Philadelphia: Wolters Kluwer Health. pp. 802–3. ISBN 0-7817-7456-X. Retrieved 2008-11-23.
- Goehring, Richard V. (2008). Mims' medical microbiology. (4th ed. ed.). Philadelphia, PA: Mosby Elsevier. p. 656. ISBN 978-0-323-04475-2.
- Mårdh PA, Novikova N, Stukalova E (October 2003). "Colonisation of extragenital sites by Candida in women with recurrent vulvovaginal candidosis". BJOG 110 (10): 934–7. doi:10.1111/j.1471-0528.2003.01445.x. PMID 14550364.
- Schiefer HG (1997). "Mycoses of the urogenital tract". Mycoses 40 (Suppl 2): 33–6. doi:10.1111/j.1439-0507.1997.tb00561.x. PMID 9476502.
- Akpan A, Morgan R (August 2002). "Oral candidiasis". Postgraduate Medical Journal 78 (922): 455–9. doi:10.1136/pmj.78.922.455. PMC 1742467. PMID 12185216.
- Nwokolo NC, Boag FC (May 2000). "Chronic vaginal candidiasis. Management in the postmenopausal patient". Drugs Aging 16 (5): 335–9. doi:10.2165/00002512-200016050-00003. PMID 10917071.
- Odds FC (1987). "Candida infections: an overview". Crit. Rev. Microbiol. 15 (1): 1–5. doi:10.3109/10408418709104444. PMID 3319417.
- Choo ZW, Chakravarthi S, Wong SF, Nagaraja HS, Thanikachalam PM, Mak JW, Radhakrishnan A, Tay A (2010). "A comparative histopathological study of systemic candidiasis in association with experimentally induced breast cancer". Oncology Letters 1 (1): 215–222. doi:10.3892/ol_00000039. ISSN 1792-1082. PMC 3436220. PMID 22966285.
- David LM, Walzman M, Rajamanoharan S (October 1997). "Genital colonisation and infection with candida in heterosexual and homosexual males". Genitourin Med 73 (5): 394–6. doi:10.1136/sti.73.5.394. PMC 1195901. PMID 9534752.
- Bassetti M, Mikulska M, Viscoli C (December 2010). "Bench-to-bedside review: therapeutic management of invasive candidiasis in the intensive care unit.". Critical Care 14 (6): 244. doi:10.1186/cc9239. PMID 21144007.
- Srikumar Chakravarthi, Nagaraja HS (2010). "A comprehensive review of the occurrence and management of systemic candidiasis as an opportunistic infection". Microbiology Journal 1 (2): 1–5. ISSN 2153-0696.
- Moosa MY, Sobel JD, Elhalis H, Du W, Akins RA (2004). "Fungicidal Activity of Fluconazole against Candida albicans in a Synthetic Vagina-Simulative Medium". Antimicrob. Agents Chemother. 48 (1): 161–7. doi:10.1128/AAC.48.1.161-167.2004. PMC 310176. PMID 14693534.
- Craigmill A (December 1991). "Gentian Violet Policy Withdrawn". Cooperative Extension University of California -- Environmental Toxicology Newsletter 11 (5).
- Morschhäuser J (Jul 18, 2002). "The genetic basis of fluconazole resistance development in Candida albicans.". Biochimica et Biophysica Acta 1587 (2-3): 240–8. doi:10.1016/s0925-4439(02)00087-x. PMID 12084466.
- Soong D, Einarson A (Mar 2009). "Vaginal yeast infections during pregnancy.". Canadian family physician Medecin de famille canadien 55 (3): 255–6. PMC 2654841. PMID 19282531.
- Jurden L, Buchanan M, Kelsberg G, Safranek S (June 2012). "Clinical inquiries. Can probiotics safely prevent recurrent vaginitis?". The Journal of family practice 61 (6): 357, 368. PMID 22670239.
- Abad CL, Safdar N (June 2009). "The role of lactobacillus probiotics in the treatment or prevention of urogenital infections--a systematic review.". Journal of chemotherapy (Florence, Italy) 21 (3): 243–52. doi:10.1179/joc.2009.21.3.243. PMID 19567343.
- Pappas PG, Kauffman CA, Andes D, Benjamin DK, Calandra TF, Edwards JE, Filler SG, Fisher JF, Kullberg BJ, Ostrosky-Zeichner L, Reboli AC, Rex JH, Walsh TJ, Sobel JD (Mar 1, 2009). "Clinical practice guidelines for the management of candidiasis: 2009 update by the Infectious Diseases Society of America.". Clinical infectious diseases : an official publication of the Infectious Diseases Society of America 48 (5): 503–35. doi:10.1086/596757. PMID 19191635.
- Williams D, Lewis M (Jan 28, 2011). "Pathogenesis and treatment of oral candidosis.". Journal of oral microbiology 3. doi:10.3402/jom.v3i0.5771. PMC 3087208. PMID 21547018.
- Anil Ghom, Shubhangi Mhaske (2010). Textbook of oral pathology. New Delhi: Jaypee Brothers Medical Publishers. pp. 498, 508–514. ISBN 978-81-8448-402-1.
- Bouquot, Brad W. Neville , Douglas D. Damm, Carl M. Allen, Jerry E. (2002). Oral & maxillofacial pathology (2. ed. ed.). Philadelphia: W.B. Saunders. pp. 189–197. ISBN 0-7216-9003-3.
- Lalla RV, Patton LL, Dongari-Bagtzoglou A (April 2013). "Oral candidiasis: pathogenesis, clinical presentation, diagnosis and treatment strategies.". Journal of the California Dental Association 41 (4): 263–8. PMID 23705242.
- Gow, Neil (8 May 2002). "Candida albicans - a fungal Dr Jekyll and Mr Hyde". Mycologist 16 (01). doi:10.1017/S0269915X02006183.
- Lynch DP (August 1994). "Oral candidiasis. History, classification, and clinical presentation.". Oral surgery, oral medicine, and oral pathology 78 (2): 189–93. doi:10.1016/0030-4220(94)90146-5. PMID 7936588.
- Obladen M (2012). "Thrush - nightmare of the foundling hospitals.". Neonatology 101 (3): 159–65. doi:10.1159/000329879. PMID 22024688.
- Scully, Crispian. "Mucosal Candidiasis (Medscape)". WebMD LLC. Retrieved 8 September 2013.
- International Code of Botanical Nomenclature. Königstein. 2000. ISBN 3-904144-22-7. Retrieved 2008-11-23.
- Odds, FC (1987). "Candida infections: an overview.". Critical reviews in microbiology 15 (1): 1–5. doi:10.3109/10408418709104444. PMID 3319417.
- Stephen Barrett, M.D. (October 8, 2005). "Dubious "Yeast Allergies"".
- Barrett S (2005-10-08). "Dubious "Yeast Allergies"". QuackWatch. Retrieved 2008-02-21.
- Jarvis WT. "Candidiasis Hypersensitivity". National Council Against Health Fraud. Retrieved January 2014.
|Wikimedia Commons has media related to Candidiasis.|