To the Editor:
Rios Fernandez, et al1 have reported significantly decreased serum 25-hydroxyvitamin D (25OHD) levels in patients with systemic sclerosis (SSc) from the south of Spain. Since 25OHD levels have been studied predominantly in sun-rich countries such as Italy, Spain, and Israel1,2,3,4,5,6,7, we evaluated the serum levels of 25OHD in a large cohort of patients with SSc from Germany.
Patients with SSc were prospectively recruited over a 2-year period (n = 137). Patients were taking no 25OHD substitution. The study was conducted in accord with the Declaration of Helsinki and followed a protocol approved by our institutional review board; informed consent was obtained from all subjects.
Where appropriate, the diagnosis was based on clinical, histological, and serological findings. Two subtypes of SSc, diffuse cutaneous SSc and limited cutaneous SSc, were distinguished, as described8. A standardized full examination was performed in all patients9. Serum 25OHD levels were assessed using the direct competitive chemiluminescence Liaison® immunoassay. The lowest …
Address correspondence to Dr. Gambichler; E-mail: t.gambichler{at}klinikum-bochum.de