Background: Autoimmune necrotizing myopathy with anti-signal recognition particle antibodies (ANM-SRP) is regarded as refractory myositis, whereby some patients respond poorly to conventional immunosuppression and require B cell depletion treatment. This study aimed to evaluate factors associated with refractory ANM-SRP.
Results: Clinical and pathological data from 48 patients with ANM-SRP were collected. We followed up clinical symptoms and image changes over 12 months. Univariate and multivariate analyses were undertaken to determine the associations between variables of interest and poor response to therapy. Refractory ANM-SRP appeared in 32.5% of patients who showed no or minimal improvement after 12 months of steroid therapy. The clinical risk factors for refractory patients were being male (OR, 19.57; P<0.001), severe muscle weakness (OR, 7.51; P<0.001) and concurrent interstitial lung disease (OR, 39.70; P<0.001). The imaging refractory-related factor was the fatty infiltration rate of thigh muscles over 3 months (P=0.022) and the pathological factor associated with refractory ANM-SRP was the high expression of B cell activating factor receptor (BAFF-R) in muscle (P=0.036).
Conclusion: Being male, severe muscle weakness, concurrent interstitial lung disease, quick development of muscle fatty infiltration and more BAFF-R and B lymphocyte infiltration in muscle indicate a poor response to immunosuppressive therapy in patients with ANM-SRP.
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
Figure 6
Loading...
Posted 27 May, 2020
On 08 Jul, 2020
On 27 May, 2020
On 18 May, 2020
On 17 May, 2020
On 17 May, 2020
Received 16 Apr, 2020
On 16 Apr, 2020
Received 15 Apr, 2020
On 26 Mar, 2020
On 24 Mar, 2020
Invitations sent on 24 Mar, 2020
On 18 Feb, 2020
On 17 Feb, 2020
On 17 Feb, 2020
On 17 Feb, 2020
Posted 27 May, 2020
On 08 Jul, 2020
On 27 May, 2020
On 18 May, 2020
On 17 May, 2020
On 17 May, 2020
Received 16 Apr, 2020
On 16 Apr, 2020
Received 15 Apr, 2020
On 26 Mar, 2020
On 24 Mar, 2020
Invitations sent on 24 Mar, 2020
On 18 Feb, 2020
On 17 Feb, 2020
On 17 Feb, 2020
On 17 Feb, 2020
Background: Autoimmune necrotizing myopathy with anti-signal recognition particle antibodies (ANM-SRP) is regarded as refractory myositis, whereby some patients respond poorly to conventional immunosuppression and require B cell depletion treatment. This study aimed to evaluate factors associated with refractory ANM-SRP.
Results: Clinical and pathological data from 48 patients with ANM-SRP were collected. We followed up clinical symptoms and image changes over 12 months. Univariate and multivariate analyses were undertaken to determine the associations between variables of interest and poor response to therapy. Refractory ANM-SRP appeared in 32.5% of patients who showed no or minimal improvement after 12 months of steroid therapy. The clinical risk factors for refractory patients were being male (OR, 19.57; P<0.001), severe muscle weakness (OR, 7.51; P<0.001) and concurrent interstitial lung disease (OR, 39.70; P<0.001). The imaging refractory-related factor was the fatty infiltration rate of thigh muscles over 3 months (P=0.022) and the pathological factor associated with refractory ANM-SRP was the high expression of B cell activating factor receptor (BAFF-R) in muscle (P=0.036).
Conclusion: Being male, severe muscle weakness, concurrent interstitial lung disease, quick development of muscle fatty infiltration and more BAFF-R and B lymphocyte infiltration in muscle indicate a poor response to immunosuppressive therapy in patients with ANM-SRP.
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
Figure 6
Loading...