Seborrheic Dermatitis on Penis

Seborrheic dermatitis is a common skin condition. It is a papulo-squamous disorder of the skin which usually affects the oily areas where sebum production is high. It is generally seen on the scalp but can also be seen in other areas like the face, nasolabial folds, eyebrows, upper chest, armpits, back, groins, gluteal cleft and genitalia.

Cause of Seborrheic Dermatitis

Seborrheic dermatitis is caused by the proliferation of a skin pathogen called as Malassezia in its yeast form. The yeast degrades the sebum to produce fatty acids. These fatty acids lead to irritation of skin and resultant dermatitis.Seborrheic dermatitis has been associated with certain medical conditions like Parkinson’s disease, depression and Tardive dyskinesia. It is often seen in immuno-compromised patients like those suffering from human immunodeficiency virus (HIV), or patients remaining immuno-suppressants after organ transplant. Patients taking medicines like lithium, systemic corticosteroids and haloperidol may also suffer from seborrheic dermatitis. Some scientists have postulated that this condition is familial and is often seen in patients with a family history of psoriasis.The likelihood of a person developing seborrheic dermatitis depends upon the amount of sebum he produces, the properties of sebum (which vary from person to person), and the response of the person’s immune system to the growth of Malassezia yeast. As the skin barrier function varies from one person to another, so does the clinical presentation.

Prevalence of Seborrheic Dermatitis

It is believed that seborrheic dermatitis affects 3% to 5% of the population. It usually begins during late adolescence and is commonly seen in young adults and elderly people. The disease has a predilection for males though females may also get affected.

Presentation of Seborrheic Dermatitis

Seborrheic dermatitis is characterized by scaly erythematous red patches which are well demarcated. These patchy lesions may coalesce at a later stage to form a bigger lesion.Seborrheic dermatitis of the penis appears as a red plaque which is scaly in nature and runs along the glans of the penis and its shaft.The condition is non-contagious and generally reflects a poor hygiene. It is recurrent in nature. This means that with appropriate treatment, the symptoms may vanish only to reappear after some time. It does not affect the overall health of the person but can become uncomfortable and embarrassing.

Diagnosis of Seborrheic Dermatitis

The condition is usually diagnosed on the basis of physical appearance of the lesions. In certain cases, a biopsy may be required to differentiate it from other fungal conditions like tinea.

Differential Diagnosis of Seborrheic Dermatitis

The differential diagnosis includes:

• Psoriasis
• Atopic dermatitis
• Tinea
• Erythroplasia Queyrat or Bowen’s disease of the glans

Treatment of Seborrheic Dermatitis

Treatment of seborrheic dermatitis usually involves a multipronged approach. This includes:

• Keratolytics: Keratolytics like salicylic acid, lactic acid, propylene glycol and urea are used to remove the stubborn scales.
• Topical Antifungal Medicines: These medicines are used against the Malassezia yeast and include ketoconazole or ciclopirox for topical application. In cases where Malassezia strain is resistant to these agents, zinc pyrithione or selenium sulfide is employed.
• Topical Corticosteroids: These may be used for duration of 1 to 3 weeks to reduce inflammation.
• Oral Antifungal/Antibiotics: In cases which are resistant to topical medication, systemic antifungal medicines like itraconazole or antibiotics like tetracycline may be useful.
• Phototherapy: In few cases, phototherapy may also play a role in treating the condition.