Tinea versicolor is a superficial fungal infection of the skin which causes hypopigmented [light colored] or hyperpigmented macules [dark colored] spots on chest and back.
The infection is caused by Malassezia genus of fungus that is found on everyone’s skin.
Versi means several and the term implies discoloration of the skin, with colors ranging from white to red to brown.
The condition affects teens and adults mostly [probably due to oily skin] but is less common in young children and elderly [unless they live in a tropical or subtropical area.]
Tinea versicolor is now called pityriasis versicolor.
Pityriasis versicolor is not dangerous or contagious but causes cosmetic concerns in the affected persons.
Tinea versicolor occurs more commonly in hot humid regions where it has 50% affection rate as low as 1.1% in the colder temperatures.
There is no sex and racial predilection.
About one-fifth of these patients have a family history of the condition. These patients have higher recurrence rate and longer duration of the disease.
Pathophysiology
Tinea versicolor is caused by genus Malassezia organisms which include [ Malassezia globosa, Malassezia sympodialis, and Malassezia furfur among others. These organisms are normally present on healthy skin.
This fungal infection is localized to stratum corneum layer of the skin.
Then why does infection occur?
Though the reasons are not entirely known few factors could increase the likelihood of disease occurrence. A combination of factors could be responsible
- Genetic predisposition
- Warm, humid environments
- Immunosuppression
- Malnutrition
- Pregnancy
- Cushing disease
- Application of oily preparations like bath oils and skin lubricant
- Corticosteroid therapy or Cushing disease
Lipids are essential for the growth of this organism but the role of amino acid is thought to be critical fro the appearance of the disease.
Cathelicidin LL-37, a peptide plays a role in skin defense against this pathogen.
When affected people are stimulated with this organism, lymphocyte function is said to be impaired.
Different Forms of Tinea Versicolor
Form 1
- Well defined oval or round macules [non raised spot] which may coalesce to form patterns
- Macules hypo or hyperpigmented
- Fine scales present
- Mainly affect upper trunk but could be in lower trunk, neck, and proximal extremities.
- More noticeable during the summer months.
Form 2
- Affects the flexural regions, the face, or isolated parts of the extremities.
- Seen more in immunocompromised
Form 3
- Involves the hair follicle- seen in the trunk and the extremities.
- Predisposing factors are
- Diabetes
- High humidity
- Drug therapy
- Steroids
- Antibiotic therapy
- Immunosuppressants
Form 4
- Small [2-3 mm] red-brown, inflammatory papules [raised spots]
- May or may not also demonstrate a fine white scale.
- Seen the trunk
- Apart from stratum corneum, also causes an interface dermatitis in the superficial dermis.
Atrophying tinea versicolor
- Atrophic oval-to-round lesions
- Ivory colored to erythematous
- Wrinkled surface and atrophied lesion [unaffected skin normal] and the atrophy is limited to the areas of skin affected by tinea versicolor.
- Often reported after prolonged topical corticosteroid use but cases without steroid use also occur
Clinical Presentation
Abnormal pigmentation that is cosmetic concern is the chief complaint. The involved skin regions are usually the trunk, the back, the abdomen, and the proximal extremities. The face, the scalp, and the genitalia are less commonly involved. There could be hypopigmentation or hyperpigmentation. A fine, dustlike scale covers the lesions.
The lesions are often more visible in the summer because the normal skin tans and lesions do not. For the same reason, the lesions may become subtler in winters.
Sometimes, mild itching may occur but otherwise, there are no symptoms.
On examination, there would be hypopigmented to hyperpigmented macules. These may be coalescing centrally, forming oval-to-round patches.
Mild scale may be present though it is not always evident, and may require scratching or stretching.
An examination with dermoscope shows a well-demarcated lesion with fine scales.
Differential Diagnoses
- Guttate Psoriasis
- Pityriasis Alba
- Seborrheic Dermatitis
- Tinea Corporis
- Vitiligo
- Confluent and Reticulated Papillomatosis
- Erythrasma
Diagnostic Work up
The diagnosis can often be made by the clinical features and lab studies are not needed.
When required though, following tests would help –
Wood Lamp Examination
This examination under the ultraviolet black light demonstrates the coppery-orange fluorescence of tinea versicolor.
Some cases do not fluoresce though the lesions are darker than unaffected skin.
Potassium hydroxide (KOH) examination
- Shows short, cigar-butt hyphae
- Spores with short mycelium are called the spaghetti and meatballs or the bacon and eggs sign of tinea versicolor
Cultures are rarely done. There are no specific blood tests.
Skin biopsy
The organism is typically located in stratum corneum and can be detected by hematoxylin and eosin.
Rarely, the organism can be seen in the stratum granulosum, and even inside keratinocytes.
The epidermis reveals mild hyperkeratosis and acanthosis.
Dermis may show a mild perivascular infiltrate.
Treatment of Tinea Versicolor
Tinea versicolor can be successfully treated with various agents.
Topical agents are
-
- Selenium sulfide
- Zinc-pyrithione
- Sodium sulfacetamide
- Ciclopirox olamine
- Tacrolimus
- Azole and allylamine antifungals
The ointment or cream for tinea versicolor should be applied from the neck to the knees even if the lesions are in small area. This would make treatment more successful.
Different topical agents have different application regimens and should be followed.
Creams for tinea versicolor are cumbersome and extensive if the disease is widespread.
For these kinds of tinea versicolor shampoo, formulations are available [selenium sulfide, zinc-pyrithione, and ketoconazole]
For oral therapy fluconazole, and itraconazole are the preferred choices. Ketoconazole is not used due to its toxicity profile.
As oral treatment of tinea versicolor should be started after explaining the risks involved
There are reports of tinea versicolor being treated with photodynamic therapy.
Tinea versicolor has a high rate of recurrence.
Recurrence can be prevented in high-risk cases by prophylactic topical or oral therapy.
Prognosis
Tinea versicolor is a benign skin disease and not contagious.
With treatment, scaling stops after a few days but discoloration may last for weeks to months.
The condition is recurrent for some patients but again treatable. Prophylactic therapy may help reduce the high rate of recurrence.
References
- Crespo-Erchiga V, Florencio VD. Malassezia yeasts and pityriasis versicolor. Curr Opin Infect Dis. 2006 Apr. 19(2):139-47.
- Mendez-Tovar LJ. Pathogenesis of dermatophytosis and tinea versicolor. Clinics in Dermatology. 2010. 28:185-188
- Cullingham K, Hull PR. Atrophying pityriasis versicolor. CMAJ. 2014 Jul 8. 186 (10):776.
- Sepaskhah M, Sadat MS, Pakshir K, Bagheri Z. Comparative efficacy of topical application of tacrolimus and clotrimazole in the treatment of pityriasis versicolor: A single blind, randomised clinical trial. Mycoses. 2017
- Qiao J, Li R, Ding Y, Fang H. Photodynamic therapy in the treatment of superficial mycoses: an evidence-based evaluation. Mycopathologia. 2010. 170:339-343.
- Fernandez-Nava HD, Laya-Cuadra B, Tianco EA. Comparison of single dose 400 mg versus 10-day 200 mg daily dose ketoconazole in the treatment of tinea versicolor. Int J Dermatol. 1997 Jan. 36(1):64-6. .
- Burkhart CG. Tinea versicolor. J Dermatol Allergy. 1983. 6:8-12.