Nothing to Kid About

Young HS patients face delayed diagnosis and treatment initiation, study says

An international, multicenter, cross-sectional study reviewed the medical records of 481 pediatric patients diagnosed with hidradenitis suppurativa (HS) and determined that 79% of the children and adolescents with HS presented with comorbidities and advanced complications due to their disease at the time of initial diagnosis. This, according to study authors, reflects a “significant gap” between disease symptom onset and clinical recognition, which in turn delays diagnosis and critical treatment initiation of pediatric HS.

The study, published in JAMA Dermatology,1 concluded that “prospective observational and interventional studies are needed” to first strengthen clinical awareness of this underrecognized disease within the pediatric population and to then advance knowledge of how this disease behaves over time as well as optimal treatments for the pediatric HS population.

“Increased awareness and recognition of HS prevalence in children demand efforts to better understand this condition,” wrote study lead author Carmen Liy-Wong, MD, section of dermatology in the division of pediatric medicine at The Hospital for Sick Children at the University of Toronto, and colleagues.

Defining the Gap

The study included a retrospective medical record review of 481 pediatric patients with HS from 10 dermatology clinics in the United States, Canada, Australia, Italy, and Israel. Medical record data spanned 1996 to 2017, and investigators examined pediatric patient demographics, disease severity, clinical features, comorbidities, and treatments.

After analyzing the pediatric HS cases, study investigators identified a clinically meaningful diagnostic gap of nearly 2 years between the mean age at disease onset (12.5 years) and the mean age at diagnosis (14.4 years).

This “significant interval” points to the importance of raising HS awareness among health care professionals, patients, and families,” wrote the study authors.

So what’s going on during this stretch between disease onset and medical assessment? According to the study, 48% of pediatric patients reported that their initial sign or symptom of this debilitating disease was a cyst or abscess. Pain and tenderness was the second most common symptom (25%). Papules and pustules was the third most common sign at disease onset (24%).

By the time a dermatological assessment was made, however, 233 (48%) of the 481 patients studied already had scarring, and the most common symptom reported by patients was tenderness or pain (65%). Bilateral distribution of skin lesions was observed in 87% of patients and 52% of patients had only one to two body sites affected.

One factor that may play into the lag between assessment and treatment is the fact that only about 60% of the 481 pediatric patients reviewed had their disease severity graded by Hurley staging, the system to characterize disease extent in patients with HS, and the gold standard to inform HS management decisions. Among study patients who were graded, 47% were at Hurley stage 1, 45% in stage 2, and 8% in stage 3.

In addition, the study found that bacterial skin swab cultures were performed in only 119 of 481 (25%) patients and an organism was identified in 30 of 119 (25%) culture results. Normal flora was reported in 15 of 30 (50%) cultures, whereas the remaining cultures had positive results for methicillin-sensitive Staphylococcus aureus (30%), methicillin-resistant Staphylococcus aureus (13%), Staphylococcus lugdunensis (3%), and Enterococcus species (3%). 

The lack of bacterial skin swab cultures becomes important when considering that bacteria known to cause soft tissue and skin infections are associated with HS lesions.2

Path to Diagnosis

Pediatric patients who sought medical help from a dermatologist were most commonly referred by a pediatrician (45%). Referrals also came from family physicians (18%), self-referred (11%), surgeons (9%), emergency medicine physicians (5%), or other subspecialists (13%).

Hidradenitis suppurativa was actually the referring diagnosis for only 39% of the pediatric patients reviewed for this study. Other diagnoses included cysts/abscesses 27%, acne (12%), growth/bumps (9%), folliculitis/furunculosis (8%), and unknown diagnosis (8%).

Patient Characteristics

In addition to a gap between disease symptom onset and diagnosis, the pediatric HS patient population also shares several additional characteristics.

A family history of HS was present in 41% of the patients reviewed. Comorbidities were also reported in 84% of the pediatric patients analyzed, with the most common being obesity (65%). The study researchers found it interesting that when body mass index (BMI) was calculated, only 20% of patients included in the study had a “normal” weight. Additional common repetitive comorbidities include acne vulgaris (29%) and overweight (14%). 

In a related JAMA Dermatology editorial3, Joslyn Kirby, MD, MEd, and Andrea Zaenglein, MD, both of Penn State Hershey Medical Center in Pennsylvania, wrote that this study indicates additional “crucial” steps to be completed. “First, we need to increase recognition by health care clinicians and decrease delays in diagnosis and treatment through advocacy, education, and research. Second, longitudinal observational studies should be expanded to include children and adolescents to better understand and mitigate the effect of HS. Third, clinical trials should include pediatric cohorts to give them earlier access to novel therapies. Fourth, children and adolescents should be involved in the development of core outcome sets, treatment goal setting, and advocacy for themselves as patients with HS.”


  1. Liy-Wong C, Kim M, Kirkorian AY, et al. Hidradenitis Suppurativa in the Pediatric Population: An International, Multicenter, Retrospective, Cross-sectional Study of 481 Pediatric Patients. JAMA Dermatol.2021;157(4):385–391. doi:10.1001/jamadermatol.2020.5435
  2. Guet-Revillet H, Coignard-Biehler H, Jais JP, et al. Bacterial pathogens associated with hidradenitis suppurativa, France. Emerg Infect Dis. 2014;20(12):1990-1998. doi:10.3201/eid2012.140064
  3. Kirby JS, Zaenglein AL. Recognizing the Effects and Disparities of Pediatric Hidradenitis Suppurativa. JAMA Dermatol.2021;157(4):379–380. doi:10.1001/jamadermatol.2020.5434