Candidiasis (thrush) is a fungal infection caused by yeasts that belong to the genus Candida. There are many species of Candida yeasts that can cause infection in humans, the most common of which is Candida albicans.
Candidiasis genital infection is much more common in women than men, but when it does occur in males, candidiasis affects the head of the penis (the "glans penis," informally referred to as the helmet) and the foreskin, if present (the "prepuce").
The rash is also known as yeast infection, thrush, Candida, candidal balanitis, candidosis and moniliasis.
"Jock itch" does not refer to male thrush. Rather, this is an informal name for a different type of intimate fungal infection in men. Medically termed tinea cruris, jock itch affects the skin around the genitals, a groin infection that is caused by different fungi - Trichophyton or Epidermophyton.1
Contents of this article:
You will also see introductions at the end of some sections to any recent developments that have been covered by MNT's news stories. Also look out for links to information about related conditions.
Fast facts on thrush in men
Here are some key points about male candidiasis. More detail and supporting information is in the main article.
- Although Candida normally lives on the skin and mucous membranes, if there is an overgrowth it can cause symptoms that vary depending on the part of the body affected.1
- While genital Candida infection mainly occurs in women, it can also occur in men when it causes an inflammation of the glans penis - balanitis.2
- Yeast infection, thrush, Candida, candidal balanitis, candidosis and moniliasis are other names that are used for the rash.
- Yeasts can live on any part of the body, but they most like to exist in warm, moist body areas such as the mouth, vulva, vagina, armpit, under the breasts, skinfolds, between the toes and behind the foreskin.
- Risk factors that make candidiasis more likely include antibiotics, corticosteroids, immunosuppression, diabetes, poor hygiene, using too many cleansing products.
- Genital candidiasis is not considered to be a sexually transmitted infection, although sexual transmission of Candida can occur during vaginal intercourse.
- In uncircumcised men, the moist, warm space underneath the foreskin is thought to promote yeast growth. It is reported to occur more frequently when hygiene is poor, but this is not always seen in practice.3
- Symptoms may include an itchy rash, red skin, swelling, irritation and itching around the head of the penis, lumpy discharge under the foreskin or pain when urinating and during sex.
- Oral or local antifungal treatments can be used to treat candidiasis.
- Thrush can be prevented and managed with good hygiene since yeast infections thrive in moist, warm places.
What is male candidiasis (thrush in men)?
Genital candidiasis is often referred to as "yeast infection" and is very common among women - almost three quarters of adult women will have at least one yeast infection in their lifetime. By comparison with women, the infection is uncommon in men.2
Candidiasis is a mycotic infection - an infection caused by a fungus, Candida in this case. In men, genital candidiasis affects the head of the penis (the glans penis) and, if present, the foreskin (prepuce).
As well as affecting the genitals, candidiasis infection can be found on other areas of skin or mucous membrane - for example, in the mouth, when it is known as oral thrush.
Causes of male candidiasis
Candidiasis is caused by a yeast fungus, Candida. The first description of the microorganism behind the infection was made over 170 years ago, in 1839, by a 29-year-old university lecturer called Bernhard von Langenbeck.3 He went on to become one of the most prominent surgeons of the 19th century.
Candida albicans, the thrush yeast. Left: in harmless cell form; Right: in disease-causing form with cells producing hyphae that penetrate tissue. Courtesy: Jim Deacon, The University of Edinburgh
Dr von Langenbeck described the species of fungus Candida albicans. This is the Candida yeast that is most commonly found in candidiasis although other species can also be involved in the fungal infection (Candida glabrata, for example).4
Candida fungi are found naturally inside the body and on the skin - it is normal for the microbe to be there. Every human being is colonized by the fungus - but at levels that do not usually cause problems. There is evidence of yeast on the penis in up to a fifth of men who do not have any signs or symptoms of balanitis.4,5
Candida albicans causes problems only under certain conditions that allow it to thrive and grow to numbers that result in candidiasis,5 with the fungal cells producing hyphae, structures that penetrate the tissue.6
Our immune system and natural ecology of bacteria normally keep the fungal population in check, but if this balance is disturbed, the fungus can thrive. An example of this is commonly seen with newborn babies that can be affected by thrush while they develop a balanced microbial flora.5
The following risk factors make candidiasis more likely:7,8
- Antibiotics - recent broad-spectrum antibiotic use, which causes a change in the balance of the normal microbial flora. This upsets the balance and allows the Candida to overgrow
- Taking medication that suppresses the immune system such as chemotherapy or corticosteroids
- Immunosuppression - weakened immunity reduces the body's defence against the fungus and so allows Candida to thrive. HIV infection is one example of something that weakens the immunity
- Diabetes, particularly if poorly controlled. Higher levels of blood sugar allow a more conducive environment for the yeasts to thrive6
- Uncircumcised men with poor hygiene - men who have not been circumcised have a moist, dark, warm space underneath the foreskin that is favorable for yeast growth
- Personal hygiene. Chronic local irritants such as bath foam, soaps, shower gels, lubricants, etc. can irritate the penis and lead to fungal infection, which is more likely on damaged skin. Not drying carefully after washing is also a risk factor because fungus can thrive on the penis in warm, moist conditions
- Poor nutrition
- Receiving renal dialysis.
Can men get thrush from a female partner?
While genital candidiasis in men - candidal balanitis - is generally sexually acquired,4 it is not classed a sexually transmitted infection (STI or STD) because it can be present in men who are not in a sexual relationship.9
Men who have a female partner with a genital yeast infection (termed vulvovaginal candidiasis in women) do not need to seek treatment themselves unless they also get symptoms, since sex does not necessarily result in transmission of the fungal infection to men.10
Men are recommended to avoid unprotected sex with a female partner until the woman's infection has cleared up after treatment.10
On the next page we look at the symptoms of male candidiasis and how it is diagnosed. On the final page we discuss prevention and treatment of male candidiasis.