Cold stimulus-fingertip lacticemy: Standardization of the test in normal volunteers and diagnostic application for systemic sclerosis

To standardize the cold stimulus-fingertip lacticemy test (CS-FTL) in normal individuals and to establish reference levels for discrimination of normal individuals and patients with systemic sclerosis (SSc). FTL was determined before (pre-CS) and 3, 8, and 13 min after cold stimulus (post-CS) in 94 normal controls according to gender and age. Diagnostic performance of ΔCS-FTL (percentage difference between post- and pre-CS-FTL) was tested comparing 25 SSc patients and the 94 normal individuals by ROC curve analysis. Successive FTL determinations in the same fingertip yielded consistent results and the whole CS-FTL test proved to be reproducible. Pre-CS-FTL in SSc patients was higher than in normal controls ( P