Hazleen Zainal1, Adawiyah Jamil1, Norazirah Md Nor1, Min Moon Tang2. 1. Department of Medicine, University Kebangsaan Malaysia Medical Center, Kuala Lumpur, Malaysia. 2. Department of Dermatology, Kuala Lumpur Hospital, Kuala Lumpur, Malaysia.
Abstract
BACKGROUND: Defective skin's acidic mantle is a component of atopic dermatitis (AD) pathophysiology. We mapped the skin pH and determine its relationship with transepidermal water loss (TEWL), hydration and disease severity. MATERIALS AND METHODS: A cross-sectional study involving patients aged ≥18 years. Eczema Area and Severity Index (EASI) was assessed. Skin pH, TEWL and hydration were measured at 18 pre-determined sites. RESULTS: Forty-eight patients participated, 33(68.8%) females and 15(31.3%) males aged 28.46 ± 12.07 years. The overall skin pH was 5.32 ± 0.68 ranging from 5.16 ± 0.75 to 5.52 ± 0.59. The lowest pH 5.16 ± 0.75 was at anterior leg, popliteal fossae 5.18 ± 0.67, lower back 5.21 ± 0.64, forehead 5.22 ± 0.62, upper back 5.25 ± 0.65 and neck 5.26 ± 0.76. Highest pH was at the cheek 5.52 ± 0.59, anterior thigh 5.47 ± 0.68, dorsal arm 5.46 ± 0.68, volar arm 5.43 ± 0.67 and abdomen 5.39 ± 0.67. Lesional areas' pH (5.40 ± 0.13) was higher than nonlesional (5.27 ± 0.14), P = .01. pH at AD predilection sites was significantly lower non-predilection sites (5.26 ± 0.59 vs 5.34 ± 0.64). pH did not correlate with TEWL (r = .23, P = .12), EASI (r = .19, P = .20) and itch (r = .06, P = .70) but correlated with hydration r = -.33, P = .02. CONCLUSION: Skin pH was lower at AD predilection sites. There was no correlation between pH with AD severity and TEWL, pH correlated with hydration.
BACKGROUND: Defective skin's acidic mantle is a component of atopic dermatitis (AD) pathophysiology. We mapped the skin pH and determine its relationship with transepidermal water loss (TEWL), hydration and disease severity. MATERIALS AND METHODS: A cross-sectional study involving patients aged ≥18 years. Eczema Area and Severity Index (EASI) was assessed. Skin pH, TEWL and hydration were measured at 18 pre-determined sites. RESULTS: Forty-eight patients participated, 33(68.8%) females and 15(31.3%) males aged 28.46 ± 12.07 years. The overall skin pH was 5.32 ± 0.68 ranging from 5.16 ± 0.75 to 5.52 ± 0.59. The lowest pH 5.16 ± 0.75 was at anterior leg, popliteal fossae 5.18 ± 0.67, lower back 5.21 ± 0.64, forehead 5.22 ± 0.62, upper back 5.25 ± 0.65 and neck 5.26 ± 0.76. Highest pH was at the cheek 5.52 ± 0.59, anterior thigh 5.47 ± 0.68, dorsal arm 5.46 ± 0.68, volar arm 5.43 ± 0.67 and abdomen 5.39 ± 0.67. Lesional areas' pH (5.40 ± 0.13) was higher than nonlesional (5.27 ± 0.14), P = .01. pH at AD predilection sites was significantly lower non-predilection sites (5.26 ± 0.59 vs 5.34 ± 0.64). pH did not correlate with TEWL (r = .23, P = .12), EASI (r = .19, P = .20) and itch (r = .06, P = .70) but correlated with hydration r = -.33, P = .02. CONCLUSION: Skin pH was lower at AD predilection sites. There was no correlation between pH with AD severity and TEWL, pH correlated with hydration.
Authors: Lisa A Beck; Michael J Cork; Masayuki Amagai; Anna De Benedetto; Kenji Kabashima; Jennifer D Hamilton; Ana B Rossi Journal: JID Innov Date: 2022-04-26