Determination of inflammation of reflex sympathetic dystrophy at early stages with Tc-99m HIG scintigraphy: preliminary results.

The pathogenesis of reflex sympathetic dystrophy (RSD) is not completely understood. However, an excessive regional inflammation, sensitization of primary somatosensory afferents, and sensitization of spinal neurons are considered to have a role in the pathogenesis of RSD. The underlying pathophysiology relating the clinical picture may help to determine the pharmacotherapeutic approach for an individual patient. Scintigraphy using radiolabelled human polyclonal non-specific immunoglobulin (HIG) has been recognized as a useful tool for the localization of inflammatory disorders. Thirty-six consecutive RSD patients associated with hemiplegia were included in this study. All the patients in this study had three phases bone scan and Tc-99m HIG scintigraphy. On admission, of 36 patients with positive bone scan, 30 had positive Tc-99m HIG scan. All the patients were symptomatic at the time of bone scanning. On the contrary, 24 out of 36 patients subsequently became asymptomatic at an 8-month re-evaluation period. Tc-99m HIG scintigraphy is a non-invasive complementary method for the determination of ongoing inflammatory reactions which also aids the clinicians to predict the response to anti-inflammatory therapy at the very early phase of RSD associated with hemiplegia. This preliminary study may be a source of inspiration for further studies with larger series and longer follow-up .