Algorithm provides quicker diagnosis of hidradenitis suppurativa

Panama City, Panama - Hidradenitis suppurativa (HS) is a challenging disease to treat; however, a better understanding of the disease and continued research has led to more clear-cut therapeutic options, according to an expert who spoke at the North American Clinical Dermatologic Society meeting.

Characterized by the development of recurrent chronic painful nodules and abscesses, HS lesions can often progress to dermal contractures, induration and fibrotic scarring, adding to the misery of this unfortunate patient population. Lesions typically occur on apocrine gland bearing skin such as in the axilla, groin, perianal, buttocks and inframammary areas but can also occur in other regions such as the ears and malar face.

While the Sartorius score is a dynamic score more suitable for clinical trials in HS patients much in the same way that the Psoriasis Area Severity Index (PASI) score is used for psoriasis, the Hurley staging system is readily used to help classify the clinical severity of the disease. Approximately 75 percent of affected patients will have stage 1 disease, typically characterized by single or multiple abscesses without sinus tracts or scarring, followed by 24 percent with stage 2 with single or multiple widely separated abscesses as well as scarring and/or tract formation. Fortunately, stage 3 disease is seen in only 1 percent of patients, who typically have diffuse or near diffuse involvement or multiple interconnected sinus tracts and abscesses across an entire affected region.

Recent research has led to the development of a simple diagnostic algorithm with key features focused on location, recurrence and chronicity of the disease, in order to help clinicians arrive at the definitive diagnosis and further, allowing them to implement more targeted therapies in a timely manner (Alikahn A, Lynch PJ, Eisen DB. J Am Acad Dermatol. 2009;60(4):539-561).

“Unfortunately, the diagnosis is not always straightforward given the incidence of staph and MRSA (methicillin-resistant Staphylococcus aureus) infections seen today. However, the diagnostic algorithm put forward by the Alikahn group has significantly helped us in more accurately diagnosing HS,” says Catherine Ramsay, M.D., Permanente Medical Group, Oakland, Calif. “It is important to rule out Crohn’s disease if patients have any GI (gastrointestinal) symptoms and when in doubt, I will often perform a culture to rule out infection and to help confirm the diagnosis.”

Therapeutic options

Once the diagnosis is firmly established, clinicians can select one of numerous therapeutic options, ranging from conservative to surgically oriented procedures. According to Dr. Ramsay, an elucidation of the potential pathogeneses of the disease including follicular occlusion, defective follicular support, biofilm disease, coagulative negative staphylococcus infection as well as autoinflammatory response via the innate immune system has helped clinicians understand a therapeutic hierarchy and why some treatment approaches prove more effective than others.

According to Dr. Ramsay, the general treatment measures for all Hurley stages include avoidance of skin trauma, hygiene and appropriate choice of soap, smoking cessation and weight management, avoidance of irritating dressings, topical pain control, as well as patient education and support.

“Given the psychological distress caused by this disorder, patients should be told that it is neither contagious nor caused by poor hygiene,” she says. “They should be offered resources for psychological support and advised to avoid skin trauma and use gentle skincare. While smoking cessation and weight loss may not improve HS, their association with HS and overall negative impact on health lead to the recommendation of these measures.”

For Hurley stage 1 disease, Dr. Ramsay recommends as first-line therapy topical approaches such as a benzoyl peroxide (BPO) 10 percent wash to address the biofilm issue and topical clindamycin lotion, followed by a short-term regimen of oral doxycycline or tetracycline useful in flares. Patients who are allergic to the tetracycline class could try oral dapsone.

For patients with lesions in the axilla, Dr. Ramsay advises her patients to consider Nd:YAG laser hair removal treatment. In addition, patients should also take a daily regimen of zinc tablets, as these have been shown to help the innate immune system function better.

Combination approach

Systemic antibiotics (i.e. clindamycin or minocycline plus rifampin), hormonal therapy (i.e. metformin or spironolactone) and oral retinoids (i.e. acitretin or isotretinoin) can all be used for stage 2 disease. Here, Dr. Ramsay says it is not uncommon that a combination of these approaches can sometimes be more effective than monotherapy, such as oral retinoids together with anti-androgen therapy.

According to Dr. Ramsay, biologics including infliximab (Remicade, Janssen), adalimumab (Humira, AbbVie), etanercept (Enbrel, Amgen), ustekinumab (Stelara, Janssen) and anakinra (Kineret, Sobi) are reserved as the last treatment option when other approaches have been tried and failed.

“I think the biologics - which are often used in stage 3 disease achieving varying results, as well as intravenous antibiotics - are given more to make the surgeons feel more comfortable proceeding to try and calm down that background inflammatory response. In stage 3, the biologics are not likely going to be curative at that point in the development of HS, at which time a wide excision is usually needed either with CO₂ laser or surgical techniques,” Dr. Ramsay says.

Interestingly, Dr. Ramsay says there is a 100 percent recurrence rate of lesions when incision and drainage (I&D) techniques are performed. In stark contrast, however, patients will fare much better when a “de-roofing” technique is performed, in which the surgeon takes the top off the inflammatory nodule, curettes the base, and allows for secondary healing.

“The inflammatory response and the innate immune system explains why lesions tend to recur even after wide excision, and why medications such as the biologics that help to calm down the immune response are helpful,” Dr. Ramsay says.

The de-roofing technique is more amenable to the patient and is more skin sparing, Dr. Ramsay says, with fewer recurrences of lesions. As some surgeons may not be aware of the inefficacy of I&D in HS lesions, Dr. Ramsay says it is paramount that the clinician recommend this technique to the surgical team in order to help ensure the best outcomes from the surgical procedure.

“I believe that we finally have some good options that we can offer our HS patients, and that there is a rationale to the hierarchy of therapy based on the Hurley stages and based on what has been tried and failed,” she says. “These can serve as some guideposts to help us find the most effective treatment in the individual patient.”

Disclosures: Dr. Ramsay reports no relevant financial interests.

For more information:

For those seeking a reference for HS, including a practical approach to therapy, Dr. Ramsay recommends: Scheinfeld N. Dermatol Online J. 2013;19(4):1.