Acne Inversa (Hidradenitis Suppurativa)

Introduction

• Description: Acne inversa (formerly hidradenitis suppurativa, Verneuil disease) is a chronic, unrelenting, refractory infection of the skin and subcutaneous tissue that is initiated by the obstruction and subsequent inflammation of follicles and apocrine glands, with resultant sinus and abscess formation. This process may involve the axilla, vulva, and perineum.

• Prevalence: Uncommon. Four to five times more common in females than in males. It is reported to occur in as many as 4% of women in some studies.

• Predominant Age: Reproductive age (not observed before puberty). Peak age 18–29 years.

• Genetics: Suggestions of a family pattern, but a strong genetic link for most cases remains unproved. (In some studies, as many as 38% of patients have a similarly affected relative and a locus at chromosome 1p21.1-1q25.3 along with mutations in the secretase genes NCSTN, PSENEN, and PSEN1 and others have been reported. Pyogenic arthritis, pyoderma gangrenosum, acne, and hidradenitis suppurativa have been associated with a novel mutation of the PSTPIP1 gene.)

Etiology and Pathogenesis

• Causes: Recurrent infections that arise in subcutaneous nodules. Proposed—hypersensitivity to androgens and follicular occlusion with rupture. It is likely that dysregulation of the immune system is a contributor.

• Risk Factors: Proposed—excessive heat, perspiration, tight clothing, smoking, and obesity.

Signs and Symptoms

• Solitary, painful, deep-seated inflamed nodule (0.5–2 cm in diameter)

• Recurrent and chronic inflammatory and ulcerated portions of labia associated with pain and foul-smelling discharge

• Multiple draining sinuses and abscesses

• Open comedones and scarring

Diagnostic Approach