Hidradenitis suppurativa (acne inversa) is a chronic, intrinsic skin disorder belonging to the group of acneiform disorders, characterised by recurrent abscesses and scarred lesions in flexural areas such as the groin or armpits.
Acute abscesses can be treated by incision and systemic antimicrobial treatment, as necessary.
Patients often need long-term topical maintenance therapy and, in some cases, long courses of antimicrobials or other systemic treatment.
In severe cases, operative treatment may be required.
The disease may impair the quality of life greatly, causing significant psychosocial suffering and functional problems.
Weight loss and smoking cessation will help.
Epidemiology
Onset often in early adulthood but may also occur at a later age.
Prevalence is estimated at 0.4-1.7%; the disease is probably underdiagnosed and undertreated.
Clear statistical association with smoking, overweight, metabolic syndrome, and type 2 diabetes
Possibly increased prevalence of axial spondylarthropathy, ankylosing spondylitis and inflammatory bowel disease (Crohn's disease, in particular).
Symptoms and findings
Diagnostic features include chronic and recurrent abscesses and scarred lesions in flexural areas (linear scar, cysts, nodules and keloids, fistulas).
In some cases, acneiform (comedones and scarring folliculitis) or weeping and ulcerative lesions (pyogenic granuloma, ulceration or erosion) can be seen in flexural areas.
These usually occur bilaterally and typically in the groin or armpits.
Patients often have either a history of or ongoing acne on the face and upper trunk. Severe forms of acne (acne conglobata) can also be seen.
Differential diagnosis
Recurrent folliculitis or furunculosis (usually with lesser symptoms and no definite scarring of the skin) Skin Abscess and Folliculitis
Abscess (usually caused by Staphylococcus aureus, individual, asymmetric, more randomly located, clearly purulent) Skin Abscess and Folliculitis
Ringworm (common in the groin; after topical corticosteroids have been used, the lesions may become more papulopustular and resemble abscesses, ‟tinea incognito”) Dermatomycoses
Skin manifestations of Crohn's disease (the groin and perianal area, ulceration, soft nodules, fistulas associated with the bowel disease) Crohn's Disease
Skin cancer, lymph node or skin metastases (for instance, individual, sharply defined, poorly healing ulcers or abscess-like lesions, or enlarged lymph nodes in the groin, or other signs of malignancy)
Hygiene and cosmetic products, such as fatty ointments, mechanical occlusion, friction, in some patients a hot environment, sweaty work, spending time in a hot climate
Internal factors (e.g. medicines, such as corticosteroids, lithium, iodine, antiepileptic medication, testosterone, anabolic steroids)
Bacterial culture from abscess if resistance to antimicrobial medication is suspected
Samples for microscopy and fungal culture, as necessary, when ringworm is suspected.
At the acute stage, topical treatment should be intensified by using the medication daily for 1 to 2 months, for instance, and subsequently, when symptoms have calmed down, 2 to 3 times weekly as long-term therapy.
Exacerbations can be treated by incision of individual abscesses and systemic antimicrobial treatment. The first line antimicrobial drugs are flucloxacillin 750-1000 mg 3 times daily, sulpha-trimethoprim 160 mg/500 mg twice daily or cephalexin 500 mg 3 times daily, for a total of 7 to 10 days. In case of hypersensitivity, clindamycin can be used.
A course of analgesics, such as paracetamol or an NSAID, is often also required.
In mild but widespread, as well as in severe cases, topical treatment should be combined with long-term systemic antimicrobial treatment (of 2 to 3 months), such as a tetracycline-group drug (e.g. 500 mg tetracycline twice daily, 300 mg lymecycline twice daily or 100 mg doxycycline once daily). Clindamycin (300 mg twice daily) has also been used as an alternative.
Specialist consultation
A dermatologist should be consulted in severe cases resistant to treatment.
Long-term systemic antimicrobial treatment and, in extremely severe cases, the retinoid acitretin or a biological drug (adalimumab, infliximab) may be necessary.
In the case of single cystic, chronically suppurative lesions consult a plastic surgeon, as necessary.
Good results have also been obtained with more extensive excision and reconstruction performed by a plastic surgeon.
In the case of severe psychological problems (e.g. severe depression), consult a psychiatrist
References
Gulliver W, Zouboulis CC, Prens E ym. Evidence-based approach to the treatment of hidradenitis suppurativa/acne inversa, based on the European guidelines for hidradenitis suppurativa. Rev Endocr Metab Disord 2016;17(3):343-351. [PubMed]
Jfri A, Nassim D, O'Brien E ym. Prevalence of Hidradenitis Suppurativa: A Systematic Review and Meta-regression Analysis. JAMA Dermatol 2021;157(8):924-931. [PubMed]
Sivanand A, Gulliver WP, Josan CK ym. Weight Loss and Dietary Interventions for Hidradenitis Suppurativa: A Systematic Review. J Cutan Med Surg 2020;24(1):64-72. [PubMed]
Bui TL, Silva-Hirschberg C, Torres J ym. Hidradenitis suppurativa and diabetes mellitus: A systematic review and meta-analysis. J Am Acad Dermatol 2018;78(2):395-402. [PubMed]
Patel KR, Lee HH, Rastogi S ym. Association between hidradenitis suppurativa, depression, anxiety, and suicidality: A systematic review and meta-analysis. J Am Acad Dermatol 2020;83(3):737-744. [PubMed]