Goniochromatic assessment of gray scales for color change.

The dependence of color differences on the illumination and viewing directions for two widely used gray scales for color change (SDCE and AATCC) was evaluated through measuring the spectral bidirectional reflectance distribution function (BRDF) by a gonio-spectrophotometer of metrological quality. Large incidence and viewing angles must be specially avoided using these gray scales because, in these conditions, color differences vary considerably from those established in ISO 105-A02 and ASTM D2616-12. While the visual appearance of the SDCE and AATCC gray scales for color change is similar, our results indicate that their goniochromatic properties are different. Finally, some recommendations regarding observation distance and illumination angle are given to correctly use these gray scales for visual experiments.

Statin therapy does not seem to benefit giant cell arteritis.

OBJECTIVE: Since statins interfere with a variety of immune-inflammatory pathways shared by atherosclerosis and giant cell arteritis (GCA), they might be potentially useful as adjunctive therapy to glucocorticosteroids in GCA. Our aim was to examine whether concomitant use of statins had any potential benefit in GCA. METHODS: Retrospective follow-up study of an unselected population of 121 patients with GCA. A comparative analysis between patients with and without statin therapy was performed. RESULTS: At the time of the GCA diagnosis, 30 patients (25%) had already been receiving statins and continued taking them during the corticosteroid treatment. No statistically significant reduction in the incidence of severe ischemic complications (including visual manifestations, jaw claudication, cerebrovascular accidents, ischemic heart disease, and limb claudication due to large artery stenosis) was observed in this group compared with the remaining patients. When we analyzed follow-up data, we found no significant differences between groups in terms of frequency of relapses, incidence of aortitis, and percentage of patients recovered from GCA. The duration of therapy and corticosteroids requirements among patients in permanent remission was similar in both groups. CONCLUSION: We did not observe a significant benefit derived from the use of statins at low to moderate doses in the incidence of severe ischemia or the disease outcome.

Influence of previous corticosteroid therapy on temporal artery biopsy yield in giant cell arteritis.

OBJECTIVE: To determine the impact of prior corticosteroid treatment on temporal artery biopsy (TAB) yield to establish the diagnosis of giant cell arteritis (GCA). METHODS: Retrospective study of a consecutive cohort of 78 patients clinically diagnosed and managed as GCA, who received corticosteroids before TAB. RESULTS: Among the 78 patients, TAB was positive in 57 (73%) and negative in 21 (27%). No significant differences in the length of the specimen were found between the positive and negative biopsies. We grouped patients according to treatment duration before TAB. In those with newly diagnosed GCA treated with high-dose steroid therapy, the biopsy results were positive in 78% (35/45) of patients treated for less than 2 weeks, in 65% of those treated for 2 to 4 weeks (13/20), and in 40% of those treated for more than 4 weeks (2/5). We also observed 8 patients that developed GCA on a background of a prior history of polymyalgia rheumatica (PMR); in this group biopsy was positive in 88% of the cases, after a median duration of treatment of 180 +/- 172 days and an average daily dose of 7.1 +/- 1.4 mg/d. CONCLUSION: The performance of TAB should not delay the prompt institution of steroid therapy on diagnosis of GCA, since the diagnostic yield of TAB seems valuable within 4 weeks of starting high-dose steroid treatment. In patients that developed GCA on a background of a prior history of PMR, a late TAB is also generally informative despite long-term treatment with low doses of corticosteroids.

Low serum levels of DHEAS in untreated polymyalgia rheumatica/giant cell arteritis.

OBJECTIVE: To address a controversy regarding the existence of a relative adrenal hypofunction in patients with untreated polymyalgia rheumatica (PMR) and giant cell arteritis (GCA) we evaluated baseline serum levels of ACTH, cortisol, and DHEAS in a cohort of patients with recent onset PMR/GCA not previously treated with glucocorticoids, in comparison with healthy controls. Possible correlations between baseline DHEAS levels and laboratory measures of disease activity were also explored. METHODS: Basal serum levels of these hormones were prospectively investigated in 25 patients with active untreated disease and compared with those of 25 age- and sex-matched control subjects. RESULTS: Of the 25 patients, 19 had isolated PMR and 6 had biopsy-proven GCA + PMR. Basal levels of cortisol and ACTH in PMR/GCA patients did not differ from control subjects; in relation to inflammatory status, lower than expected basal production of cortisol was observed in active untreated PMR/GCA. Baseline serum DHEAS levels were significantly lower in all patients compared with controls. In these patients, a significant correlation was found between baseline DHEAS values and laboratory measures of disease activity. The percentage of DHEAS reduction and the severity of inflammatory response were higher in women than in men. CONCLUSION: Patients with PMR/GCA with new-onset active disease before steroid treatment have inappropriately normal cortisol levels regarding the ongoing inflammation, and significantly lower levels of DHEAS compared to the age- and sex-matched healthy control subjects. These data support the existence of a relative adrenal hypofunction in PMR and GCA.