Overview
Definition:
Tinea versicolor, also known as pityriasis versicolor, is a superficial fungal infection of the skin caused by lipophilic yeasts of the genus Malassezia
It is characterized by dyspigmented macules and patches, typically on the trunk and proximal extremities.
Epidemiology:
It is common worldwide, particularly in tropical and subtropical climates
It primarily affects adolescents and young adults, though it can occur at any age
Prevalence varies, but it is estimated to affect 5-10% of the general population, with higher rates in certain geographic areas and among immunocompromised individuals
In pediatrics, it is more frequently seen in post-pubertal children and adolescents.
Clinical Significance:
While generally a benign and cosmetic concern, accurate diagnosis and management are important for patient reassurance and to prevent misdiagnosis of other more serious dermatological conditions
Understanding its prevalence and typical presentation is crucial for pediatricians managing common childhood skin complaints.
Clinical Presentation
Symptoms:
Typically asymptomatic
Mild itching may be present
Patients may notice changes in skin pigmentation
Lesions are usually found on the chest, back, shoulders, and neck
Lesions can be hypopigmented (lighter than surrounding skin), hyperpigmented (darker), or erythematous (reddish-brown)
The affected skin may scale subtly
Lesions can coalesce to form larger patches.
Signs:
Characteristic macules and patches with fine scale
The scale is often best visualized when the skin is stretched, a phenomenon known as the "fine scale" or "cigarette paper" scale
Lesions are often ill-defined and may appear slightly raised
The distribution is typically truncal, sparing the face and distal extremities in children, though facial involvement can occur
Wood's lamp examination may reveal yellow-green fluorescence in active lesions, though this is not always present.
Diagnostic Criteria:
Diagnosis is primarily clinical, based on the characteristic appearance and distribution of lesions
Definitive diagnosis can be confirmed by microscopic examination of skin scrapings
KOH preparation of skin scrapings shows short hyphae and clusters of yeast, described as a "spaghetti and meatballs" appearance
The causative organism, Malassezia species, is a normal commensal of the skin but can proliferate under certain conditions.
Diagnostic Approach
History Taking:
Inquire about the onset and progression of skin changes
Ask about any associated symptoms like itching or discomfort
Note any previous episodes or similar conditions in family members
Ascertain exposure to heat, humidity, or oily skin products, which can predispose to the condition
Consider any underlying medical conditions or medications that might affect immune status or skin flora.
Physical Examination:
Perform a thorough dermatological examination, focusing on the trunk, neck, and proximal limbs
Note the color, size, shape, and distribution of the lesions
Palpate for scale
Assess for any signs of inflammation or secondary infection
Examine the entire skin surface for other dermatological conditions
Use a Wood's lamp if available for characteristic fluorescence.
Investigations:
Potassium hydroxide (KOH) preparation of skin scrapings is the primary investigation
Scrape scales from active lesions onto a clean slide, add a drop of 10-20% KOH, and examine under a microscope for the presence of short hyphae and yeast spores
Culture is generally not required for diagnosis
Biopsy is rarely needed but can be diagnostic, showing fungal elements in the stratum corneum.
Differential Diagnosis:
Vitiligo: Characterized by depigmented macules that are usually well-demarcated and lack scaling
Pityriasis rosea: Often starts with a herald patch followed by widespread oval, pink, scaly lesions distributed along cleavage lines
Post-inflammatory hypopigmentation: Can occur after various inflammatory dermatoses and lacks the characteristic Malassezia morphology on KOH prep
Secondary syphilis: Can present with a generalized rash, including hypopigmented lesions on the trunk
Other fungal infections like tinea corporis: Typically present as annular, erythematous, scaly plaques with central clearing.
Management
Initial Management:
Treatment aims to eradicate the yeast and manage dyspigmentation
Topical antifungal agents are the first line of treatment for most cases
Reassurance is important as the condition is benign.
Medical Management:
Topical antifungals: Selenium sulfide 2.5% shampoo, applied to affected areas and left on for 10-15 minutes before rinsing, used daily for 1-2 weeks
Ketoconazole 2% shampoo or cream, applied as per selenium sulfide or to the affected skin twice daily for 2 weeks
Other topical agents include clotrimazole, miconazole, and econazole
Oral antifungals: For extensive or recurrent cases, oral agents like fluconazole (e.g., 150-400 mg single dose, or weekly doses for 2-3 weeks) or itraconazole may be considered, though caution is advised in pediatric patients due to potential side effects and drug interactions
Itraconazole is generally not recommended for children due to limited safety data and the need for therapeutic drug monitoring
Fluconazole is often the preferred oral agent when indicated, with appropriate dosing.
Supportive Care:
Advice on hygiene and avoiding predisposing factors such as excessive sweating or occlusive clothing
Patients should be informed that pigmentation may take months to return to normal even after successful treatment
Recurrence is common, so patient education on recognizing early signs and initiating treatment is crucial.
Age Specific Dosing:
Topical agents are generally safe and can be used in children
For oral therapy, fluconazole dosing in children is typically weight-based, e.g., 3-6 mg/kg/day, usually given as a single daily dose for 1-2 weeks, or a single dose of 8 mg/kg
However, the decision to use oral antifungals in children should be made by a specialist, considering the risks and benefits
Adult dosages for fluconazole (e.g., 150 mg single dose) are sometimes adapted for older children and adolescents based on weight, but specialist consultation is recommended.
Complications
Early Complications:
Rarely, patients may experience skin irritation or allergic reactions to topical antifungal medications
Cosmetic concerns related to persistent dyspigmentation are the most common "complication" from a patient perspective.
Late Complications:
Recurrence of tinea versicolor is very common, often occurring within months to a year, especially in individuals with predisposing factors such as humid climates, oily skin, or immunosuppression.
Prevention Strategies:
Regular use of antifungal shampoos during warm, humid months can help prevent recurrence
Maintaining good skin hygiene and avoiding excessive sweating can also be beneficial
Educating patients about early signs of recurrence and initiating prompt treatment is key.
Prognosis
Factors Affecting Prognosis:
The prognosis is generally excellent with appropriate treatment
Recurrence rates are high, influenced by individual susceptibility, environmental factors, and adherence to prophylactic measures.
Outcomes:
Most patients achieve clearance of the fungal infection within 2-4 weeks of treatment
However, the normalization of skin pigmentation can take several months, and hypopigmented macules may persist for a longer duration
Complete resolution of dyspigmentation is expected with time and sun exposure.
Follow Up:
Follow-up is usually not required unless there is treatment failure or frequent recurrence
Patients should be advised to seek medical attention if symptoms persist or if the condition recurs frequently
Education on self-monitoring and preventative measures is paramount for long-term management.
Key Points
Exam Focus:
Tinea versicolor is a superficial fungal infection caused by Malassezia yeast
Key findings include dyspigmented macules on the trunk
KOH prep shows "spaghetti and meatballs" morphology
Selenium sulfide and ketoconazole shampoos are first-line treatment
Recurrence is common.
Clinical Pearls:
Always consider tinea versicolor in pediatric patients presenting with truncal hypopigmentation or hyperpigmentation, especially with fine scaling
Wood's lamp can be helpful
Educate parents and children about the prolonged period for pigment normalization and the high recurrence rate
Topical therapies are usually sufficient
oral antifungals should be used judiciously in children.
Common Mistakes:
Misdiagnosing tinea versicolor as vitiligo or post-inflammatory changes without microscopic confirmation
Inadequate treatment duration, leading to recurrence
Overuse of oral antifungals in children for uncomplicated cases
Failure to counsel patients on the cosmetic sequelae and recurrence potential.