Disorders of the groin and skinfolds

Introduction

• Important to avoid combination corticosteroid/antifungal products
  • Clouds diagnostic picture
  • Steroid often too potent for occluded intertriginous areas and can lead to irreversible striations with long-term use

Tinea cruris

• Jock itch due to fungal infection
• Invasion of stratum corneum by dermatophytes
• Transmitted by direct contact person-to-person, animal-to-person (cats/dogs) or fomites
• Symmetrical erythema with peripheral annular slightly scaled edge
• Penis and scrotum are spared (distinguishing feature)
• May have coincident tinea pedis (with spread by putting on pants)
• Treatment
  • Topical clotrimazole BD
  • Keep area clean and dry
  • Loose-fitting clothing
  • Antifungal powder daily to prevent recurrence

Candida intertrigo

• Commonly diaper of infants, vulva and groin of women and glans penis of uncircumcised males (balanoposthitis) and inframammary and pannus folds
• Often co-exists with other intertriginous disorders
• Typically erythema, maceration with peripheral small erythematous papules or pustules (satellite lesions) – characteristic
• Often burning or itching sensation
• Treatment
  • Dry and cool
  • Air drying or drying with hair dryer after bathing
  • Topical clotrimazole BD then antifungal powders daily to prevent recurrence
  • Treat vaginal candidiasis if exists
  • If balanitis – treat female partner also as often has vaginal candidiasis
  • Zinc oxide barrier if in nappy after clotrimazole application

Scabies

• Intensely pruritic eruption 30 days after exposure to organism
• Mostly nocturnal itching
• Adults: slightly longitudinal erythematous or brown papules, mostly on lateral feet, wrists, ankles, interdigital spaces, axillae, groin and extensor surfaces of extremities. Head and neck characteristically spared
• Children: usually more generalised with face, scalp and neck involvement
• Treatment
  • Permethrin cream 5% from neck down (in adults), left on for 12 hours, then washed off
  • Use for all family members and repeat in 1 week
  • Wash all bed linen and clothing in hot water or leave in plastic bags

Pediculosis pubis

• Pubic lice infestation
• Multiple small, flesh or slightly reddish organisms grab onto pubic hair near skin
• Treat as for scabies

Seborrhoeic dermatitis

• Dandruff within skin folds
• Treat with antidandruff shampoo +- topical hydrocortisone

Intertrigo

• Diaper dermatitis
• Irritant dermatitis due to moisture, heat, friction and irritating urine/faeces
• Satellite pustules are absent if no candida infection
• Consider streptococcal superinfection if marked erythema, tenderness, very young or old or immunocompromised
• Treatment
  • Keep area dry and cool. Loose-fitting clothing
  • Avoid all potential irritants
  • Zinc oxide ointment
  • Treat secondary bacterial infection if suspected
  • If significant inflammation, consider topical hydrocortisone 1% short-course

Psoriasis

• Flexural (inverse) psoriasis lacks prominent silvery scale
• Presents as thin erythematous plaques, with central fissure
• Low potency steroids (due to occluded surfaces of intertriginous regions) such as hydrocortisone 2.5% alternating with vitamin D analogues

Hidradenitis suppurativa

• Recurrent, painful, draining nodules in apocrine regions
• Due to follicular occlusion, rupture of follicular contents and intense inflammation
• Treatment
  • Clindamycin 1% topically twice daily
  • Chlorhexidine soap 1-2 times weekly
  • Minimise I&D as leads to scarring

Last Updated on October 13, 2021 by Andrew Crofton