Laser Doppler flowmetry for assessing localized scleroderma in children

Abstract

Objective. Assessment of disease activity is a major challenge in the management of children with localized scleroderma. The aim of this study was to evaluate the role of laser Doppler flowmetry (LDF) in comparison with infrared thermography in the detection of scleroderma disease activity.Methods. In 41 children with localized scleroderma, 111 lesions were assessed on 2 separate occasions, by clinical examination, LDF, and thermography. Measurements from contralateral areas of unaffected skin served as intrapatient controls, and differences in blood flow and temperature were calculated between the corresponding sites. The sensitivity and specificity to detect clinically active lesions were compared between LDF and thermography.Results. Seventy-five active lesions (34%) and 147 inactive lesions (66%) were identified clinically. The median relative increase in blood flow measured by LDF was ؉89% (range ؊69% to ؉449%) for clinically active lesions and ؉11% (range ؊46% to ؉302%) for clinically inactive lesions (P < 0.001). Thermography showed a median difference in temperature of ؉0.5°C (range ؊0.1°C to ؉4.1°C) and ؉0.3°C (range ؊1.9°C to ؉2.7°C) for clinically active lesions and clinically inactive lesions, respectively (P ‫؍‬ 0.024). Using a cutoff level of 39% to indicate increase in blood flow, a sensitivity of 80% and specificity of 77% to detect clinically active lesions were observed; for thermography, no useful cutoff level was identified. The correlation between differences in blood flow and differences in temperature was small, but significant (r 2 ‫؍‬ 0.120, P < 0.001). Conclusion. LDF is a helpful, noninvasive diagnostic technique that can be used to discriminate disease activity in children with localized scleroderma, and is more accurate than thermography for this purpose.

Localized scleroderma – classification and tools used for the evaluation of tissue damage and disease activity/severity

“…• Laser Doppler flowmetry (LDF) is a non-invasive method for the measurement of cutaneous microcirculation, particularly in inflammatory diseases and neuropathies [33]. It has high negative and positive predictive values of 94% and 84%, respectively [34].…”

“…increased blood flow within affected skin sites) reflects the active form of the disease [34]. In some cases a slight increase in blood flow found in inactive lesions may suggest persistent changes in the microcirculation or active inflammatory process which is not detectable by clinical examination yet [33]. Murray et al report that an increased perfusion in affected sites may be a result of decreased skin thickness within the plaques, which increases vascular thickness and facilitates their visualization [35].…”

“…• Laserowy przepływomierz dopplerowski (laser Doppler flowmetry -LDF) -służy do nieinwazyjnej oceny mikrokrążenia w obrębie skóry, szczególnie w chorobach zapalnych i neuropatiach [33]. Cechuje się dużą negatywną i pozytywną wartością predykcyjną, odpowiednio 94% i 84% [34].…”

“…Negatywny wynik LDF (brak różnic w przepływie krwi między skórą zmienioną chorobowo i niezmienioną) koreluje z dobrym efektem terapeutycznym, a wynik pozytywny (zwiększony przepływ krwi w obrębie zmian chorobowych) odzwierciedla aktywną postać choroby [34]. W części przypadków nieznaczny wzrost przepływu krwi w zmianach nieaktywnych wskazuje na przetrwałe zmiany w mikrokrążeniu lub obecność procesu zapalnego, który nie ma jeszcze wykładników w badaniu klinicznym [33]. Murray i wsp.…”

Diagnosis and treatment of systemic and localized scleroderma

“…In such cases, laser Doppler flowmetry can discriminate real active lesions from false-positives [62]. Some studies show that ultrasound in scleroderma may be used to assess disease activity as reflected by altered echogenicity and vascularity changes, and also to detect deeper extension of lesions beyond the dermis [63].…”