Hidradenitis suppurativa

Last Updated: 2025-02-10

Author(s): Anzengruber F., Navarini A., Reiprich K.

ICD11: ED92.0

Verneuil 1854, Plewig & Steger 1989

Acne inversa, Verneuil's disease

Chronic, recurrent, potentially mutilating skin disease of the terminal hair gland apparatus in the apocrine gland-rich regions of the body, especially in the intertriginous areas, which manifests itself with painful, inflammatory lesions.

  • Prevalence: approx. 0.4%-1% worldwide
  • Incidence: 6.0 per 100,000 inhabitants
  • Seldom before puberty or after the menopause, the average age at first manifestation is 22-23 years
  • more common in dark-skinned people and people of low socio-economic status
  • Women to men ratio 1:2 to 1:5 (controversially discussed)

Active, inflammatory form: IHS4 classification

 

IHS4 score
Number of nodules x1
Number of abscesses x2
Fistulas / sinus x4

<4 points: mild HS
4-10 points: moderate HS
>10 points: severe HS

 

Inactive, non-inflammatory form

Hurley Score:

  • I Single or multiple abscesses without scarring or fistulas
  • II Recurrent abscesses and nodules with sinus tract formation or scarring: single or multiple widely separated lesions
  • III Diffuse or near-diffuse involvement with multiple interconnected sinus tracts, scarring, and abscesses across entire area

 

Hurley degree Abscesses Cords of scar tissue Extensive infestation
I + - -
II + + -
III + + +

 

The two pillars of HS/AI pathogenesis:

  1. an abnormal differentiation of the keratinocytes of the hair follicle
  2. a massive accompanying inflammation

 

an abnormal differentiation of the keratinocytes of the hair follicle -> hyperkeratosis with occlusion of the upper part of the hair follicle -> dilatation -> rupture of the follicle -> purulent-melting inflammatory reaction -> scarring -> sinus formation

 

  • Predisposing factors:
    • Nicotine consumption
    • Obesity
    • Tight clothing or friction
    • Hyperhidrosis
    • Genetic predisposition (34% of first-degree relatives of HS/AI patients also suffer from HS/AI)

 

  • Comorbidity:
    • Psoriasis
    • Chronic inflammatory bowel disease
    • Axial spondyloarthritis, arthritis of the small and medium-sized joints
    • Cardiovascular diseases
    • Pyoderma gangraenosum
    • Diabetes mellitus
    • Psychiatric diseases
    • Acne triad (acne conglobata, HS, perifolliculitis capitis abscedens et suffodiens)
    • Acne tetrad (acne conglobata, HS, perifolliculitis capitis abscedens et suffodiens, pilonidal sinus (23-30%))

 

Syndromic HS/AI:

  • in the context of complex (autoinflammatory) syndromes such as PASH, PAPASH, PASS and PsAPASH
  • more pronounced and more refractory to therapy
  • individual recommendation for treatment (genetic abnormalities in IL-1 and TNF-α signalling pathways)

 

  • The primary lesion: a painful, solitary, deep-seated, cutaneous-subcutaneous lump that spontaneously regresses, persists or can transform into an abscess.
  • Abscesses can fuse in depth, spontaneously rupture outwards and form tunnels. The abscess or tunnel rupture is accompanied by a purulent and/or watery-bloody secretion.
  • Other presentations: follicular papules, cysts, pustules, narrow, intraepidermal tunnels, the double pseudocomedones, large, partly livid-erythematous, nodular, honeycomb-like areas with abscesses, tunnels and hypertrophic scars
  • Symptomatic complaints: Pain, itching, foul-smelling discharge

Typical clinical presentation with at least 2 abscesses within 6 months in the intertriginous area

Inguinal (90%), axillary (69%), perianal and perineal (37%), gluteal (27%), submammary (18%), genitofemoral, in the mons pubis and less frequently on the face, thoracic, retroauricular, capillitium, eyelids and back

Hidradenitis suppurativa / acne inversa was described by Velpeau in 1839 and named by Verneuil in 1854, who associated it with sweat glands. In 1989, Plewig and Steger introduced the term acne inversa to replace the misleading term hidradenitis suppurativa. Both terms are currently considered incorrect and are used in parallel until a more appropriate name is found based on a better understanding of the pathogenesis.

The inflammatory infiltrate is diverse and consists of lymphocytes, histiocytes, foreign body giant cells, plasma cells and neutrophil granulocytes. Depending on the degree of inflammation and stage of the HS/AI lesions, different histopathological findings can be observed. However, the histological picture is usually clear, so that differential diagnoses that are difficult to differentiate clinically can be excluded with relative certainty.

  • Chronic pain
  • Cutaneous superinfections
  • Pararectal fistulas
  • Urethral fistulas
  • Movement restrictions
  • Lymphoedema, especially genital
  • Squamous cell carcinoma (Marjolin ulcer) (early, high risk of metastasis, poor prognosis (59% mortality)
  • Higher risk of cerebrovascular insult, coronary heart disease, heart failure, PAD
  • systemic amyloidosis with subsequent kidney, heart and central nervous system damage (screening: microalbuminuria-> kidney biopsy if necessary)
  • Anaemia
  • Hypoproteinaemia

  • Weight reduction
  • Loose, non-chafing clothes
  • Avoidance of nicotine abuse
  • Long-pulse Nd:YAG laser (for hair removal)

Chronic, recurrent disease.

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