Patient Presentation
A 15-year-old female came to clinic because of a recurrent “boil” in her right axilla. She had been seen 3 weeks previously and was diagnosed with hidradenitis suppurativa as this had occurred about 3 months before in the same axilla but a different location. She had spontaneous drainage at that time and was prescribed antibiotics and a topical disinfectant. Because of problems with insurance she had not picked up the medications. She also had been referred to a dermatologist, but did not know if she had an appointment. It had gotten better but was not resolved when 1 day ago, the area became very red, swollen and painful in the same location plus an additional location close to the first. There was no drainage. She had not used any compresses but did use some antipyretic medication which did not help. She had problems sleeping because of the pain but denied any fevers or chills. She also denied any new soaps, lotions, detergents, insect bites or trauma. She had last shaved her axilla 5 days ago. The past medical history was positive for atopic dermatitis, and mild comedomal acne. She also had had some ingrown hairs in her axilla and groin in the past that she treated herself by removing the entrapped hair.

The pertinent physical exam showed a healthy female in some distress with movement of her right arm. Her vital signs were normal and her growth parameters showed her body mass index at 115% of normal for age. Her right axilla had two areas that were warm, swollen and reddened with a lead point on the swelling. The recurrent one was about 3 cm in size and the other was about 1.5 cm. The area around the larger one looked like it had some mild scarring. She some general xerosis and mild comedomal acne along her hair line. The rest of her examination was normal.

The diagnosis of hidradenitis suppurativa and obesity was made. The patient’s clinical course showed the pediatrician lancing the abscesses, starting her on antibiotics and appropriate wound management. The pediatrician worked with her pharmacy to ensure that she could get her medications, and she already had a dermatology appointment in 10 days. The laboratory evaluation of a wound culture eventually grew Staphlococcus aureus that was susceptible to all antibiotics. At her dermatology appointment they confirmed the diagnosis and began tetracycline for an initial 3-month course.

Discussion
Hidradenitis suppurativa (HS) is a recurrent, chronic inflammatory disease of the hair follicles particularly in the apocrine gland-bearing areas of the axilla, inguinal, perianal, mammary and inframammary areas. Onset is usually after puberty, in the early 20s. It is more common in females than males. Prevalence is estimated to be 0.05- 4.1%. It can be associated with premature adrenarche, metabolic syndrome and obesity.

The lesions are often pruritic, painful, and with malodorous purulent drainage. It often begins with comedomes and tender nodules, and can easily progress to painful abscesses with purulent fluid. HS can also lead to sinus tracts, hypertropic scarring and potentially contractures.

Complications include infection, scarring/contractures, lymphedema, and fistula to adjacent structures such as the rectum, bladder or other genitourinary structures. The pain can limit school, work, or activities of daily living including exercise which can also contribute to obesity. HS in the genital area can also cause hygiene and sexual health problems. The differential diagnosis includes follicular pyoderma/furuncles/carbuncles, acne, pilonidal cyst in gluteal area, cat scratch disease, cutaneous tuberculosis, metastasis, and cutaneous Crohn’s disease.

Learning Point
There is no cure for HS but treatment is guided by the extent of the problem. Consultation with a dermatologist is usually needed as this is a life-long problem. Primary care physicians can assist patients with their care through counseling about the disorder, recommending wearing loose clothing to prevent friction, good skin hygiene, weight loss and exercise, and providing psychological support.

Patients with mild disease (nonscarring inflammatory lesions) are often treated with topical antibiotics (e.g. clindamycin or resorcinol) and topical disinfectants. Patients with more extensive disease (having multiple, recurrent lesions with sinus tracts and/or scarring) or failing mild disease treatment may have oral antibiotics (e.g. tetracycline, doxycycline, minocycline, clindamycin and rifampin in various regimens or combinations) prescribed but also have immunomodulators and or steroids added. Patients may also need local surgical treatment for abscesses and sinus tracts. With extensive disease (tunnel formation, extensive scarring, contractures etc.) patients have similar treatment options but may require more extensive surgery or need short course systemic immunosuppression.

Questions for Further Discussion
1. What is the difference between a furuncle, carbuncle and abscess?
2. What are indications for referral to a dermatologist?
3. How are acne and HS similar and different?

Related Cases

Disease: Hidradenitis Suppurativa

Symptom/Presentation: Mass or Swelling | Rash

Specialty: Dermatology

Age: Teenager

To Learn More
To view pediatric review articles on this topic from the past year check PubMed.

Evidence-based medicine information on this topic can be found at SearchingPediatrics.com and the Cochrane Database of Systematic Reviews.

Information prescriptions for patients can be found at MedlinePlus for this topic: Hidradenitis Suppurativa

To view current news articles on this topic check Google News.

To view images related to this topic check Google Images.

To view videos related to this topic check YouTube Videos.

Liy-Wong C, Pope E, Lara-Corrales I. Hidradenitis suppurativa in the pediatric population. J Am Acad Dermatol. 2015;73(5 Suppl 1):S36-41. doi:10.1016/j.jaad.2015.07.051

Saunte DML, Jemec GBE. Hidradenitis Suppurativa: Advances in Diagnosis and Treatment. JAMA. 2017;318(20):2019-2032. doi:10.1001/jama.2017.16691

Pink A, Anzengruber F, Navarini AA. Acne and hidradenitis suppurativa. Br J Dermatol. 2018;178(3):619-631. doi:10.1111/bjd.16231

Author
Donna M. D’Alessandro, MD
Professor of Pediatrics, University of Iowa