High frequency ultrasound measurement of digital dermal thickness in systemic sclerosis.
BACKGROUND
Currently, assessment of dermal thickness in systemic sclerosis (SSc) is performed by palpation and assessment using the modified Rodnan skin score (mRSS).


OBJECTIVE
To verify whether high frequency ultrasound (US) may be a reliable and a reproducible method to measure digital dermal thickness.


METHODS
In 70 patients with SSc, skin thickness was evaluated with US by 2 observers at 2 different sites on the second digit of the dominant limb to determine the interobserver variability. Patients and controls were examined twice by the first observer for intraobserver variability. Patients were divided into three subgroups according to the phase of the disease (oedematous, fibrotic or atrophic).


RESULTS
At both examined areas, US showed a significant dermal thickening (p<0.001) in the whole group of patients with SSc. A low intraobserver and interobserver variability was found. A highly significant correlation between the global mRSS and the local dermal thickness at the two examined sites (p=0.032, p=0.021) was detected. Skin thickness was significantly higher in the oedematous than in the fibrotic group (p<0.001) and significantly higher in the fibrotic and the oedematous group (p<0.001) than in the atrophic group (p<0.002).


CONCLUSIONS
US is a reliable tool giving reproducible results, and is able to detect digital dermal thickening in SSc.
Kaloudi
Olga
O
Department of Biomedicine, Division of Rheumatology AOUC, Centre Denothe, University of Florence, Villa Monna Tessa, Viale Pieraccini 18, Florence 50139, Italy. olgakaloudi@hotmail.com
Bandinelli
Francesca
F
Filippucci
Emilio
E
Conforti
Maria Letizia
ML
Miniati
Irene
I
Guiducci
Serena
S
Porta
Francesco
F
Candelieri
Antonio
A
Conforti
Domenico
D
Grassiri
Genesio
G
Grassi
Walter
W
Matucci-Cerinic
Marco
M
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D020405:Dermis / Q000000981:diagnostic imaging* / Q000473:pathology; D005260:Female; D005385:Fingers / Q000000981:diagnostic imaging* / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D015203:Reproducibility of Results; D012595:Scleroderma, Systemic / Q000000981:diagnostic imaging* / Q000473:pathology; D014463:Ultrasonography; D055815:Young Adult