[Allergic diseases in the genital area].

BACKGROUND: The genital area has a high exposure to various allergens that are not always obvious. Out of shame patients may not complain about symptoms in this area. Moreover, diagnosis and therapy are often not primarily conducted by a dermatologist and allergologist. Therefore, many cases of allergic diseases in the genital area remain undetected.

OBJECTIVES: Which type I and type IV allergies occur in the genital area? Which allergens are currently of importance? Which are the characteristics of allergic diseases in the genital area? What are the symptoms and differential diagnoses? What to focus on when taking medical history and in clinical diagnostics?

MATERIALS AND METHODS: The current medical literature regarding allergic diseases in the genital area is discussed.

RESULTS: In the genital area type IV allergies such as contact dermatitis exceed type I allergies in number. Contact urticaria can occur due to seminal plasma allergy, latex allergy and a transfer of type I allergens via semen. Contact allergens are found in sex products such as condoms, but also in topical products. Methylisothiazolinone has become a new and important contact allergen for the genital area in recent years. Also, fixed drug eruption occurs preferentially in the genital area. As a delayed type IV allergy due to systemically administered drugs it has to be considered in the differential diagnosis.

CONCLUSION: Presumably, there are a high number of unreported cases of allergic diseases in the genital area. Interdisciplinary collaboration between gynecologists, urologists and dermatologist should be increased. The use of methylisothiazolinone in rinse-off and leave-on products should be discussed.