Comparison of Tc-99m MDP, Tc-99m HSA and Tc-99m HIG uptake in rheumatoid arthritis and its variants

Abstract

Tc-99m polyclonal immunoglobulin-G has been shown to be a successful agent in the depiction of active inflammation in rheumatoid arthritis (RA). The objective of this study was to compare the uptake behaviors of Tc-99m HIG and Tc-99m MDP in RA and variants of rheumatoid arthritis (VRA). Seventeen patients with RA and 8 patients with VRA presenting with active inflammation were included in this study. Ten subjects with well-diagnosed degenerative joint disease constituted the control group. All joints in patients were also imaged with Tc-99m HSA to evaluate the vascularization status of the joints. Tc-99m HIG and HSA scans were obtained at 2, 4 and 24 hours after the injection of 555 MBq Tc-99m HIG and 296 MBq Tc-99m HSA. Conventional bone scans were performed 4 hours after the injection of 740 MBq Tc-99m MDP. Target-to-background (T/B) ratios were obtained exclusively over the joint regions. Tc-99m HIG T/B ratios of the active joints in RA were significantly higher than those of the non-active joints and the control group (p< 0.05). Tc-99m HIG T/B ratios in active joints showed a progressive increase between 2 and 24 hour images (p < 0.05). In contrast, Tc-99m HSA T/B ratios decreased in all active joints significantly (p < 0.05) except the ankle joint region (p > 0.05). The T/B ratios in Tc-99m MDP bone scans were higher in all active joints than in non-active RA joints and joints of controls but significantly differences were only detected in wrist and elbow joints. All clinically active joints in VRA patients accumulated Tc-99m HIG and HSA, and showed increased Tc-99m MDP uptake. These joints had a very similar Tc-99m HIG retention pattern to the RA joints. The detection rate of active joint inflammation with Tc-99m HIG was much higher than that with Tc-99m MDP. The increasing Tc-99m HIG uptake ratio between 2 and 24 hours in contrast to Tc-99m HSA indicates the presence of other binding mechanisms besides increased vascularity in RA.

The Agreement Between Blood Pool - Delayed Bone Scintigraphy and Tc-99m Human Immunoglobulin G (HIG) Scintigraphy in the Determination of the Presence and Severity of Inflammatory Arthritis

“…Many of the studies have shown that nonspecific polyclonal human IgG scintigraphy is a useful test for localizing and detecting inflammatory joint activity and inflammation (23,24,25,26,27,28,29,30). …”

“…In the literature, LPBS has been compared to HIG scintigraphy in inflammatory arthritis for only in the determination of the presence of inflammatory arthritis (24,29). However, there is not enough information about the agreement between LPBS - HIG scintigraphy in the determination of the severity of disease.…”

Molecular imaging of rheumatoid arthritis: emerging markers, tools, and techniques

“…Increased uptake of 18  F-FDG in the joints is not specific for RA, as this also occurs in infectious and degenerative forms of osteoarthritis [32]. Radiolabeled diphosphonates do not locate primarily to inflammatory sites, but detect alterations in bone metabolism, especially increased pathological osteoblast activity [33,34]. SPECT imaging with 99m technetium-methylene diphosphonate ( 99m Tc-MDP) is clinically approved for the assessment of bone damage in RA and is used to monitor patients with active arthritis [33] (Figure 3).…”

“…Radiolabeled diphosphonates do not locate primarily to inflammatory sites, but detect alterations in bone metabolism, especially increased pathological osteoblast activity [33,34]. SPECT imaging with 99m technetium-methylene diphosphonate ( 99m Tc-MDP) is clinically approved for the assessment of bone damage in RA and is used to monitor patients with active arthritis [33] (Figure 3). This tracer has proven to be useful for arthritis imaging in the past but provides limited insight into the disease process.…”

Weiterbildungsverbünde Allgemeinmedizin in Deutschland - eine Bestandsaufnahme

“…Ergebnisse werden hier nicht berücksichtigt, es wird auf die Literatur verwiesen [7,8]. Ergebnisse werden hier nicht berücksichtigt, es wird auf die Literatur verwiesen [7,8].…”