LB898 Validation of the paindetect questionnaire in hidradenitis suppurativa using quantitative sensory testing

Abstract

Hidradenitis suppurativa (HS) is a painful, inflammatory skin condition that causes nociceptive, neuropathic, and nociplastic pain types. The PainDETECT Questionnaire (PD-Q) is a nine-item survey that has been used to assess the likelihood of neuropathic pain character. However, it has not been validated in HS. Quantitative Sensory Testing (QST) is a standardized series of sensory exams considered the gold standard for evaluation of sensory dysfunction including neuropathic pain. Evaluating the performance of the PD-Q in HS may enable clinicians to screen for neuropathic pain in HS and tailor pain management. In this observational, cross-sectional study, 20 participants with HS underwent QST at a control site on the dorsal hand and a painful HS lesion to evaluate pain phenotype including the presence of neuropathic pain. Participants also completed the PD-Q. Participants were of young age (median 36 years, IQR 30-47) and mostly female (75%) and of Black race (55%). 14 participants (70%) were Hurley stage 2, and 5 (20%) were Hurley stage 3. Participants had substantial inflammatory activity per IHS4 (15, 10-42). 17 HS lesions (85%) were draining tunnels and 3 (15%) were inflammatory nodules. 13 HS lesions (65%) were in the axilla, 6 (30%) were in the groin, and 1 (5%) was on the chest. 10 participants (50%) exhibited neuropathic pain on QST, defined by the presence of dynamic mechanical allodynia at the HS lesion. On the PD-Q, 7 participants (35%) were classified as unlikely having neuropathic pain, 7 (35%) as indeterminate for neuropathic pain, and 6 (30%) as likely having neuropathic pain. QST and the PD-Q demonstrated 75% agreement for pooled likely or indeterminate presence of neuropathic pain versus absence of neuropathic pain with a Cohen's k of 0.5 (p = 0.01) demonstrating moderate agreement. Compared to the gold standard of QST, the PD-Q has modest agreement in screening for neuropathic pain character in HS. Because pain phenotype strongly informs management of chronic pain, the PD-Q may be a useful clinical tool for directing management of HS pain.