Penile Dermatitis

Penile dermatitis is inflammatory dermatosis of the glans, prepuce or shaft, also called balanoposthitis when both glans (balanitis) and foreskin (posthitis) are involved.

• Causes:
  • Irritant contact dermatitis (commonest): soap, shower gel, wet wipes, spermicide, urine and sweat trapped under the foreskin, excessive washing, friction, condoms of latex (latex is also a contact allergen).
  • Allergic contact dermatitis: latex, lubricant constituents, fragrances, topical drugs (neomycin, benzocaine).
  • Infective: Candida albicans (especially in diabetes, sodium glucose cotransporter 2 inhibitor use, uncircumcised men), Group A and B streptococcus, anaerobes, Staphylococcus aureus, Trichomonas vaginalis, herpes simplex, syphilis, scabies.
  • Dermatoses: seborrhoeic dermatitis, psoriasis (glossy red plaques, often without scale), lichen planus, lichen sclerosus (balanitis xerotica obliterans), Zoon plasma cell balanitis, fixed drug eruption.
  • Premalignant and malignant: erythroplasia of Queyrat (squamous cell carcinoma in situ, a persistent red velvety patch) and invasive squamous cell carcinoma must be excluded in persistent or atypical lesions.
• Risk factors: uncircumcised, poor hygiene or over washing, diabetes, obesity, immunosuppression, incontinence, sexual partner with vaginal candidiasis.
• Complications: phimosis, paraphimosis, scarring and meatal stenosis (lichen sclerosus), balanitis recurrence, and malignant transformation in lichen sclerosus.

• Itch, burning, soreness, erythema, tenderness, swelling, discharge or odour under the foreskin, painful retraction, superficial fissures, painful intercourse.
• Candidal: red glans with white satellite papules or pustules and a cheesy deposit.
• Bacterial: well demarcated erythema, oedema, purulent smelly discharge.
• Lichen sclerosus: white atrophic, shiny, sclerotic patches, phimosis, meatal narrowing, haemorrhagic fissures.
• Psoriasis: well defined red plaques; seborrhoeic: greasy scale, with scalp and face involvement.
• Red flags: ulcer, non-healing lesion, induration, warty or fungating growth, persistent red patch for over 4 weeks, inguinal lymphadenopathy, bleeding, new pigmented lesion, recurrent paraphimosis, urinary obstruction.

• Clinical, with history of irritants and sexual exposure.
• Swab for bacterial culture and Candida; first void urine nucleic acid test for chlamydia and gonorrhoea if risk; syphilis serology and herpes PCR for ulcers; urinalysis and glucose or HbA1c to screen for diabetes (dipstick glycosuria).
• Patch testing in suspected allergic contact dermatitis.
• Skin biopsy for lesions that fail to respond to 4 weeks of treatment, atypical, indurated or pigmented lesions, and suspected lichen sclerosus, Zoon balanitis or erythroplasia.

• General care: wash with plain water or an emollient wash (aqueous cream is itself an irritant, so use emulsifying ointment instead); avoid soap, shower gel and wipes; retract the foreskin, rinse and dry carefully; apply emollient (white soft paraffin) as a barrier; wear loose cotton underwear; change wet clothes; use non-latex condoms if allergic.
• Irritant or eczematous dermatitis: hydrocortisone 1 percent cream applied thinly once or twice daily for 7 to 14 days; for moderate cases use clobetasone butyrate 0.05 percent once or twice daily for up to 2 weeks.
• Candidal balanitis: clotrimazole 1 percent cream applied twice daily for 2 weeks (or until 1 week after clearance), or miconazole 2 percent cream twice daily; a combination of hydrocortisone 1 percent with clotrimazole 1 percent twice daily for 7 days shortens symptoms. Oral fluconazole 150 mg as a single dose for resistant or extensive disease (repeat at day 7 if needed). Check glucose and review SGLT2 inhibitor if applicable. Treat partner if symptomatic.
• Bacterial balanitis: saline bathing; flucloxacillin 500 mg orally four times daily for 7 days (clarithromycin 250 to 500 mg twice daily for 7 days if penicillin allergic); metronidazole 400 mg orally three times daily for 5 to 7 days if anaerobes or Trichomonas.
• Seborrhoeic dermatitis: ketoconazole 2 percent cream once or twice daily for 2 to 4 weeks plus low potency steroid for flares.
• Psoriasis: hydrocortisone 1 percent for 1 to 2 weeks; avoid vitamin D analogues on the genitalia because they irritate; consider tacrolimus 0.1 percent ointment twice daily (specialist advice).
• Lichen sclerosus: clobetasol propionate 0.05 percent ointment once daily at night for 4 weeks, then on alternate nights for 4 weeks, then twice weekly for 4 weeks; maintenance twice weekly thereafter and as needed for flares; use a fingertip unit as the quantity (about 0.5 g); refer to dermatology or urology; circumcision for refractory phimosis; annual review because of cancer risk.
• Recurrent balanitis: circumcision after medical measures fail or in lichen sclerosus with scarring.
• Refer urgently within 2 weeks for suspected penile cancer (any persistent lesion for 4 weeks or more not responding to treatment, ulcer, induration, growth).
• Follow up at 2 to 4 weeks; no response needs biopsy.