Patients with hidradenitis suppurativa may experience neuropathic, nociplastic pain

Key takeaways:

• Patients with hidradenitis suppurativa experienced sensory loss to innocuous cold and warmth, noxious heat and light touch.
• Patients experienced hypersensitivity to deep pressure pain and cutaneous pinpricks.

Patients with hidradenitis suppurativa may be susceptible to multiple types of pain including neuropathic and nociplastic pain, according to a study.

“Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease characterized by recurrent painful nodules, abscesses and scarring tunnels,” Ali Alsouhibani, PT, PhD, of the department of anesthesiology at Emory University School of Medicine in Atlanta and the department of physical therapy at Qassim University in Saudi Arabia, and colleagues wrote. “Pain is consistently rated as the most important symptom, leading to negative psychological impact, reduced quality of life and increased risk of long-term opioid use.”

According to study, the three “generally recognized” measurements for pain include nociceptive pain, neuropathic pain and nociplastic pain, each stemming from different pain receptors or processes.

Using quantitative sensory testing (QST), Alsouhibani and colleagues defined the somatosensory profiles in patients with HS at both clinically affected and nonaffected sites. This was done in comparison with pain-free reference data. The researchers used t tests compared sensitivity in HS lesions with sensitivity in the hand, which was considered the control location, and in pain-free control.

The cross-sectional study included 20 participants (median age, 35.5 years; 15 women). Two participants were Asian, 11 Black, six white and one mixed race or ethnicity.

Further, 15 participants were classified with severe HS, whereas the remainder were considered moderate. Draining tunnel type lesions were tested in 17 individuals and inflammatory nodules were tested in the remaining three.

Results showed that HS lesions experienced sensory losses to innocuous cold (t = 5.69) and warmth (t = 10.2), noxious heat (t = 3.84) and light touch (t = 4.46) compared with unaffected skin sites (P < .001 for all).

On the other hand, HS lesions were highly sensitive to deep pressure pain (t = 8.36; P < .001) and cutaneous pinpricks (t = 2.07; P = .046); however, unaffected sites experienced sensitivity to deep pressure pain as well (t = 5.85; P < .001).

A subset of patients with HS also expressed responses in pain consistent with neuropathic and nociplastic pain conditions. Five patients reported hypersensitivity to repetitive pinpricking, three reported hypersensitivity to paradoxical thermal sensations and 10 reported pain upon light stroking of the skin.

“Taken together, our findings support the presence of neuropathic and nociplastic pain mechanisms in HS,” Alsouhibani and colleagues wrote.

“Additional studies that evaluate the association between QST findings and other measures of small nerve fiber function across a broader population of patients with HS are needed to further elucidate cutaneous sensory changes that may contribute to pain and itch in HS,” the researchers concluded.