Clinical Evaluation

Onset of Hidradenitis Suppurativa Symptoms

Patients may develop signs and symptoms of hidradenitis suppurativa (HS) throughout most of the life span, with most reports ranging from 15 to 60 years old. Women, who make up 70% of the HS population, tend to present in their 20s and 30s, reporting symptoms that started years earlier. There may also be smaller peak that occurs in the post-menopausal population. HS is more common in African Americans and Caucasians and may occur less frequently in Asian populations. Since the majority of HS epidemiology studies are from North America and Europe, the current HS racial demographics may not be fully representative of the actual prevalence of HS.

There is, on average, a 7-year gap between symptoms and receiving a diagnosis. The delay in diagnosis may be due to multiple factors ranging from reluctance to disclose their symptoms/signs to misdiagnosis, such as folliculitis. Additionally, patients can have gradual development of HS symptoms prior to deciding to seek care.

Initial HS symptoms include the development of multiple recurrent papules or nodules in one or more locations. Inflammatory nodules may evolve into abscesses, fistulas, and/or sinus tracts. Pocketed scarring and sinus tracts are classic features and very helpful in distinguishing this disease from folliculitis, which also tends to present with smaller, more superficial lesions. Some patients may not present with these classic features early in their HS disease or if they have only mild disease, which can lead to delay in diagnosis if a thorough patient history is not obtained. While obtaining history, clinicians should ask patients to describe their lesions and whether they have noted changes over months to years. It is often helpful to provide examples to the patient of what HS lesions look like and the locations where they tend to appear. Patients often have historical pictures they can provide as well.

A thorough history of timeline of events prior to and after HS symptom onset can also be contributory. Changes to patient’s diet, medications, weight gain, stress, tobacco use, menses onset, pregnancy, and menopause onset as relevant may aid in determining triggers. For example, in women, flares due to hormonal fluctuation are common.

Family History of Hidradenitis Suppurativa Symptoms/Diagnosis

Hidradenitis suppurativa has autosomal dominant, albeit complicated, inheritance pattern with one-third of patients reporting a family member with HS-like symptoms. Furthermore, patients with early-onset HS disease are more likely to have a family history of HS compared to patients with normal-onset HS, which is defined at onset of puberty or later. Although some genes have been identified, they do not explain the majority of cases. If available, the family member’s affected HS lesion location(s), flare triggers, and treatment history may be useful: for a patient with extensive disease and a family history of chronic HS lesions with prominent scarring, early initiation of systemic therapy should be discussed.

Pertinent Locations

Hidradenitis suppurativa is predominant, but not exclusive to apocrine gland-bearing regions. Commonly affected areas include the axillae, inframammary area, lower abdomen, inguinal region, perineum, and gluteal region. Patients will describe having multiple papules that evolve into nodules, abscesses, and/or fistulas. Scarring is a prominent feature of moderate-to-severe HS, which may appear as pocketed, cribriform scars, and/or interconnected scars.

On initial exam, the physician should examine all locations where HS may appear to keep note of lesion progression, which is common. Patients may report not having any active lesions in an area, but still present with HS lesions, such as non-draining fistulas. This should be noted on exam to have a consistent Hurley staging and Physician’s Global Assessment. Both of these assessments are described in further detail later on in this chapter.

When examining the patient, the physician can assist the patient in positioning them to examine symmetrically affected areas, such as both axillae, at the same time to minimize pain and discomfort. This technique minimizes the amount of time a patient has to be in an uncomfortable position due to limited mobility from scarring. Additionally, patients should be given the choice to remove their wound dressing. If the patient prefers keeping the dressing on, then the clinician should make note of it and ask the patient to describe any active lesions they have at the site.

When the axillae and groin are affected, patients may describe having limited mobility due to pain and scarring. Fig. 7.1 demonstrates the classic tunneling scars with overlying fibrosis and post-inflammatory hyperpigmentation seen with hidradenitis suppurativa in the axilla. Another commonly affected area is the inframammary region. Fig. 7.2 demonstrates inframammary region affected with abscesses and papules with overlying erythema in a female patient (see Fig. 7.2 A) and male patient (see Fig. 7.2 B), respectively. The groin region is also affected in HS and female patients tend to present with isolated groin disease when they have limited disease extent. Fig. 7.3 shows a few inflammatory nodules with surrounding scarring tracts in a female patient.

Lesion Count

Lesion count assessment consists of assessing the number of nodules, abscesses, and/or fistulas present. Papules are not generally formally included in the assessment. Although papules may occur as a new early lesion, most HS lesions are large and deep (> 1 cm) such that a papule-predominant presentation may prompt evaluation for another condition such as folliculitis. When counting lesions, the clinician should determine whether the lesions are interconnected, which may be part of the same underlying process. When documenting lesions, the clinician should categorize the lesion for fully assessing disease severity. While there is currently no standardized HS lesional terminology, there are available validated terminologies that can be used.

When assessing the patient, the clinician should fully visualize all the affected areas, including regions where the patient may not have any active lesions. There may still be background disease that should be noted. The physical exam may be difficult for some patients due to lesion tenderness. Additionally, patients will often have wound dressings over their lesions that are removed for the physical exam. The clinician can allow the patient to remove their own dressings to avoid any unnecessary pain in the process. New wound dressings can be offered following the physical exam.

Lesion Description

Lesion characteristics are also used for determining disease severity. On exam, fistulas may drain spontaneously or on palpation. If a patient’s fistulas no longer drain on a subsequent exam, then the disease severity score may change. HS nodule assessment also will affect the disease severity score based on tenderness presence on palpation. Patients may report tenderness even without palpation; therefore, clinicians should minimize lesion palpation for the patient unless required for scoring in a clinical trial or other disease assessment. Scarring and post-inflammatory hyperpigmentation should also be assessed to monitor for signs of improvement overtime and with HS treatment.

Documenting Other Pertinent Features on Skin Exam

Other medical conditions that have higher prevalence in patients with HS compared to the general population include metabolic syndrome. On exam, patients may appear overweight and have skin findings, such as acanthosis nigricans, which supports metabolic dysregulation. In female patients, polycystic ovarian syndrome (PCOS) is another comorbidity seen in HS. Features on physical exam include darkened hairs on the face, peri-areolar area, and groin region.