Scrotal pruritus L29.1

Itching of the scrotum is a common, polyetiological, acute or chronic or chronic-recurrent symptom that significantly reduces the quality of life of the affected person by interfering with the daily routines of life (Köhn M et al. 2018). In the case of acute itching, the triggering cause can usually be found quickly. In the case of chronic itching, a careful anamnesis must be taken in order to better understand the correlations.

Infections

• Candidiasis of the genital region
• Pediculosis pubis
• Tinea inguinalis
• Localized scabies
• Condylomata acuminata
• Oxyuriasis

Underlying dermatological diseases with itching

• Allergic contact dermatitis
• Toxic contact dermatitis (excessive cleanliness)
• Atopic dermatitis (also as localized minus variant)
• Lichen planus
• Intertrigo
• Psoriasis (intertriginous psoriasis, also occurring in isolation)
• Pemphigoid bullous (rare)
• Dyskeratosis follicularis (rare)
• Pemphigus chronicus benignus familiaris
• Lichen sclerosus et atrophicus
• Urticaria

Metabolic and endocrine disorders

• Diabetes mellitus (see also Diabetes mellitus skin changes)
• Kidney diseases (especially dialysis patients)
• Liver diseases (bilirubin elevations)
• Hyper/hypothyroidism (see also thyroid diseases, skin changes)
• Hypovitaminosis (especially B6 deficiency; pellagra with pellagroid scrotal dermatitis)
• Other systemic diseases
• Iron deficiency anemia
• Polycythemia vera
• Hodgkin's disease

Psychogenic factors:

• Psychogenic factors (defensive or desirable symptom).
• Pruritus scroti as a sign of somatoform disorder.

Other:

• Pruritus scroti in urinary and/or fecal incontinence.
• Pruritus in age-related involution processes (so-called senile pruritus)
• Pruritus in lumbosacral radiculopathy (radiological and neurological clarification - measurement of nerve conduction velocity - Cohen A et al. 2005)
• Pruritus in case of increased mechanical and/or thermal stress (continuous running, longer walks)
• Anal fissures
• Fistulas
• Inflammatory bowel disease
• Extramammary Paget's Disease (Cervantes J et al 2018).

The causes are manifold and include localized skin diseases on the one hand, polytopic skin diseases with involvement of the genitals (scrotum) on the other hand or general systemic diseases with pruritus (e.g. diabetes mellitus, chronic kidney and liver diseases or neurological diseases). In the case of pruritic internal systemic diseases, however, it is rather rare that the itching is limited to the male genitals. Ultimately, psychosomatic illnesses come into consideration.

Scratching in the scrotal area, regardless of the cause, very rapidly leads to erythema, and if scratching is prolonged, to lichenification with thickening of the scrotal skin. Roundish and striate excoriations may be seen in both the scrotum and crotch areas, often extending to the thighs.

Frequently, however, the clinical findings are discrete. There are indistinct rednesses, excoriations, possibly with crust formation, fine lamellar scaling. Prolonged intense pruritus leads to lichenification of the scrotal skin.

Chronic dermatitis: Most frequently, it was a toxic contact dermatitis, caused by chronic irritation, e.g. urinary and/or fecal incontinence, by frequent excessive washing with detergents, by the use of cosmetics, perfumes, disinfectants and others.

Long-distance runners or triathletes, for example, suffer increasingly from pruritus scroti and possibly scrotal soreness. Pruritus may also occur after long summer walks. The causes are increased sweating and prolonged mechanical irritation. Furthermore, the wearing of unsuitable briefs whose cut does not prevent direct contact between the scrotum and the inner thighs should be avoided (e.g. loose boxer shorts).

Also incontinence pads or condoms are possible contact noxes. Co-triggering are occlusive effects, due to tight-fitting clothes (Chan MP et al. 2015).

Atopic dermatitis: Not infrequently, (localized) atopic dermatitis is the cause of pruritus in the genital area. Lichen simplex chronicus may also be causative.

Contact allergic dermatitis: Serious allergens in male genital itching are clothing; underwear and its additives e.g. dyes. Especially dark colors can cause allergic reactions, as well as fragrances in moist toilet papers or detergents.

Infections: Another cause of scrotal itching are infections with yeasts (mostly Candida albicans) and filamentous fungi. Furthermore, crabs and scabies should be excluded.

Senile atrophy of the scrotum: Age involution of the scrotum can lead to considerable parchment-like atrophy of the scrotal skin with exsiccosis pruritus and fine lamellar scaling (Berger TG et al. 2013).

Therapy depends on the underlying cause (see also under genital eczema). In toxic or allergic dermatitis, short-term therapy with a class II glucocorticoid will be useful. Infection-related pruritus requires specific therapy (antifungal, antiscabi). In senile scrotal atrophy, consistent oily care and avoidance of irritants of any kind are recommended (Kantor GR 1990). In cases of systemically triggered pruritus, interdisciplinary medical care is required, which usually leads to education and successful therapy. Somatoform disorders should also be considered.

In the case of puritus scroti, attention should also be paid to diseases of the glans penis (balanitis), and also to a disease of the inner preputial leaf (posthitis). In the area of the glans penis, attention should always be paid to the presence of lichen sclerosus et atrophicus, zoon balanitis or candidabalanitiis.

1. Berger TG et al (2013) Pruritus in the older patient: a clinical review. JAMA 310:2443-2450.
2. Cervantes J et al (2018) Enlarging bump on the scrotum. Skin Appendage Disord 5:52-55.
3. Chan MP et al (2015) Vulvar dermatoses: a histopathologic review and classification of 183 cases. J Cutan Pathol 42: 510-518

4. Cohen A et al (2005) Neuropathic scrotal pruritus: anogenital pruritus is a symptom of lumbosacral radiculopathy. J Am Acad Dermatol 52:61-66

5. Kantor GR (1990) What to do about pruritus scroti. Postgrad Med 88:95-96

6. Köhn M et al (2018) IN: G. Plewig et al (eds), Braun-Falco`s Dermatology, Venereology and Allergology. Springer Reference Medicine p.1504
7. Surani A et al (2018) Multiple pruritic plaques on scrotum-what is your diagnosis? Indian J Sex Transm Dis AIDS 39:141-142.