169 Poor validity of hidradenitis suppurativa diagnostic criteria in pediatric patients

Abstract

Although HS commonly presents in adolescence, diagnostic criteria have not been validated in children. This study aimed to determine the proportion of pediatric patients who met HS diagnostic criteria at time of diagnosis. We conducted a single-center retrospective chart review of pediatric patients identified by HS ICD-9/10 code from January 1, 2012–July 1, 2021. We collected data on demographics and fulfillment of major diagnostic criteria: (1) typical lesion, 2) typical location, 3) recurrence (>2 flares in past 6 months)). We present descriptive statistics as proportions and fisher’s exact tests. 296 patient records were included in the study. The majority were female (78.1%), Latinx (39.2%), and Black (18.9%). Median age at disease onset was 14 years (IQR 12-16 years). 55.1% (N=163) of patients were documented to have met all three diagnostic criteria at diagnosis. 96.0% (121/126) of patients who did not meet all criteria failed to meet the recurrence criterion. 79.3% (96/121) of patients who did not meet the recurrence criterion at diagnosis had additional visit records that were examined for flare frequency. Additional lesions consistent with HS were documented in 68 patients. Of 28 patients who had ≥1 lesion consistent with HS before their diagnostic visit, 10 had a documented lesion within a 6-month interval. With these additional data, diagnostic criteria were actually fulfilled in 58.4% (173/296) of patients at the time of diagnosis. Of 40 patients who had ≥1 lesion consistent with HS after their diagnostic visit, 33 (82.5%) had lesions within a 1-year period. Patients who did not meet major diagnostic criteria were less likely to have ever received a diagnosis by dermatology (34.1% vs 55.0% p < 0.001). Over 40% of pediatric HS patients do not meet all major diagnostic criteria. Many pediatric patients experience disease recurrence at a longer interval, suggesting that this criterion may be too strict for the pediatric population.