I read with interest the report by Fragoso-Loyo et al (1) describing the quantification of interleukin-6 (IL-6) and chemokines in cerebrospinal fluid (CSF) as an accurate indicator of neuropsychiatric involvement in systemic lupus erythematosus (NPSLE) that could be useful in the followup and evaluation of treatment response in these patients. It is always a pleasure when our observations are confirmed and extended by other investigators. However, Fragoso-Loyo and colleagues cited the wrong paper as their reference 10: our article in Clinical Immunology and Immunopathology (2), in which no data on NPSLE were included. We reported the elevated levels of IL-6 in CSF from patients with NPSLE in Arthritis & Rheumatism in 1990 (3). Therefore, Fragoso-Loyo et al should refer to this report instead of our paper in Clinical Immunology and Immunopathology, and provide comments on the relevance of our findings to theirs.
Correct Citation Regarding Interleukin-6 Levels in Cerebrospinal Fluid from Patients with Neuropsychiatric Lupus: Comment on the Article by Fragoso-Loyo et al
To the Editor:
- 1 , , , , , , et al. Interleukin-6 and chemokines in the neuropsychiatric manifestations of systemic lupus erythematosus. Arthritis Rheum 2007; 56: 1242–50.
- 2 , , . Elevation of cerebrospinal fluid interleukin-6 activity in patients with vasculitides and central nervous system involvement. Clin Immunol Immunophathol 1993; 66: 225–9.
- 3 , . Elevated levels of interleukin-6 in cerebrospinal fluid from patients with systemic lupus erythematosus and central nervous system involvement. Arthritis Rheum 1990; 33: 644–9.
Shunsei Hirohata MD*, * Kitasato University School of Medicine, Kanagawa, Japan.