Candidal infection (syn. candidiasis; candidosis; moniliasis)

Candida is by far the most common type of yeast infection in human skin, more than 20 species exist with Candida albicans being the most common. The name ‘candida’ refers to the white colour of the organisms in culture.

This chapter, which is set out as below, provides a brief overview of candidal infection: .

• Humans carry yeast, including candidal species, throughout the gastrointestinal tract as part of the normal commensal flora. The vagina is also commonly colonised by yeast (13% of women)
• Candida species are not part of the normal skin flora; however, they may colonise fingers or body folds transiently
• If the host's defences are lowered, candida can cause infection of the oral mucosa, genital mucosa, skin, and rarely, deep-seated tissues

Intertrigo

• Intertrigo is an inflammatory condition of skinfolds caused by skin-on-skin friction
• Secondary infection with bacterial or fungal infection, especially candida, is common
• Intertrigo is most commonly found in the groin, axillae, and inframammary folds. It also may affect antecubital fossae; umbilical, perineal, or interdigital areas; neck creases; and folds of the eyelids
• For more information refer to the related chapter Intertrigo

Chronic paronychia

• Chronic paronychia is predominantly a disease of domestic and catering workers, bar staff and fishmongers, where water and/or chemicals cause a contact irritant dermatitis. Handling of wet foods represents a particular hazard, as these often combine several predisposing factors including wet working conditions, a cold environment and irritation from the food itself
• Yeast infections, such as candida, can be associated as either a primary or secondary event
• The condition begins as a slight erythematous swelling of the nail folds. Over time the cuticle is lost and pus may collect beneath the nail fold
• For more information refer to the related chapter Chronic paronychia  

Oral infection including angular cheilitis

• Oral candidiasis
• A number of factors predispose patients to develop candidiasis: infancy, old age, antibiotic therapy, steroid and other immunosuppressive drugs, xerostomia, anaemia, endocrine disorders, and immunodeficiency - candidiasis is a common finding in people with HIV infection. Although reports describe oral candidiasis during the acute stage of HIV infection, it occurs most commonly with falling CD4+ T-cell counts in middle and late stages of HIV disease

• The most common presentations of oral candidiasis are:
• Pseudomembranous candidiasis (syn. thrush) - white patches on the surface of the oral mucosa. Lesions develop into confluent plaques that resemble milk curds and can be wiped off to reveal a raw erythematous and sometimes bleeding base. In cases of HIV, thrush can be severe and involve the oesophagus, with resultant dysphagia or odynophagia
• Erythematous candidiasis - erythematous areas found generally on the dorsum of the tongue, palate, or buccal mucosa are characteristic. Lesions on the dorsum of the tongue present as depapillated areas. Red areas often are seen on the palate of individuals with HIV infection

• Angular cheilitis (syn. angular stomatitis; cheilosis)
  • This is a common inflammatory condition affecting the corners of the mouth or oral commissures, a primary or secondary infection with candida is relatively common
  • For more information refer to the related chapter Angular cheilitis  

Genital infection

• Candidal vulvovaginitis
• Is a candidal infection of the vaginal tract. Candida albicans is a common inhabitant of the vaginal tract and can result in itching, redness, irritation, soreness, and burning, as well as a white discharge 

• Penile candida
  • ​Mainly affects the glans penis causing a balanitis, but it can also affect the distal penile shaft
  • Clinical features can include erythema, satellite lesions, and white patches
  • For more information refer to the related chapter Balanitis  

Chronic mucocutaneous candidiasis

• Chronic mucocutaneous candidiasis (CMC) refers to a heterogeneous group of disorders characterised by recurrent or persistent superficial infections of the skin, mucous membranes, and nails with Candida organisms, usually Candida albicans. These disorders are confined to the cutaneous surface, with little propensity for systemic dissemination  

Systemic candidiasis

• Is candidal infection throughout the body
• This is a rare, but serious condition, up to 75% of people may die from the infection
• Systemic yeast infections may be a sign of more serious diseases such as diabetes, leukaemia, or HIV