Association between P-Selectin Autoantibody Positive and Response to Steroid Treatment in Newly Diagnosed Immune Thrombocytopenia Patients.

OBJECTIVE: This study aimed to detect the association between P-selectin autoantibody positive and response to steroid treatment in newly diagnosed immune thrombocytopenia (ITP) patients. METHODS: The data from 105 newly diagnosed adult ITP patients administered with first-line of steroid treatment from October 2016 to May 2021 were retrospectively analyzed. Treatment responses were evaluated within 3 months after the onset of treatment. RESULTS: Among the 105 patients, 80.00% (84/105) of patients presented with platelet glycoprotein-specific antibody positive; 44.76% (47/105) patients were anti-P-selectin positive, while 35.24% (37/105) were anti-P-selectin negative. No significant difference in overall response was observed between patients who were anti-P-selectin positive and those who were anti-P-selectin negative (74.47% vs. 89.19, χ2 = 2.910, p = 0.088). But patients who were anti-P-selectin negative had significantly higher complete response rate, compared to those who were anti-P-selectin positive (72.97% vs. 48.94%, χ2 = 4,965, p = 0.026). Logistic regression analysis revealed that anti-GP IIb/IIIa positive (OR = 3.114, p = 0.010, 95% CI: 1.313-7.388) and anti-P-selectin positive (OR = 0.309, p = 0.036, 95% CI: 0.127-0.753) were two factors that could affect patients' response. CONCLUSIONS: Our study found that ITP patients with anti-GP IIb/IIIa may have a higher response to steroid treatment, but anti-P-selectin-mediated-ITP might be less responsive to steroid treatment. In adults with ITP, the presence of anti-P-selectin autoantibodies is a predictive factor for poor response to steroid treatment.

The association between platelet glycoprotein-specific antibodies and response to short-term high-dose dexamethasone with prednisone maintenance treatment in adult patients with primary immune thrombocytopenia.

OBJECTIVE: The aim of the present study was to detect the association between platelet glycoprotein-specific autoantibodies and the patient response to short-term high-dose dexamethasone (HD-DXM) + prednisone maintenance treatment. METHODS: The data from 112 adult patients newly diagnosed with ITP who were administered first-line HD-DXM + prednisone maintenance therapy between January 2016 and January 2021 were retrospectively analyzed. RESULTS: A total of 72 patients positive for platelet glycoprotein-specific antibodies were enrolled in the antibody-positive group, and 40 patients not positive for platelet glycoprotein-specific antibodies were enrolled in the antibody-negative group. In the antibody-positive group, six platelet glycoprotein-specific antibody types were found: 41.67% of the patients were anti-GP IIb/IIIa-positive only, 5.56% were anti-GP Ib/IX-positive only, 5.56% were anti-P-selectin-positive only, 19.44% were anti-GP IIb/IIIa- and anti-GP Ib/IX-positive, 16.67% were anti-GP Ib/IX- and P-selectin-positive and 11.11% were positive for all three antibodies. There was no significant difference in the overall response rate between the antibody-positive group and the antibody-negative group (94.44 versus 80.00%, p = .221). However, the CR rate was significantly higher in the antibody-positive group than in the antibody-negative group (69.44% versus 40.00%, p = .032). The logistic regression analysis revealed that platelet glycoprotein-specific antibody positivity and age were two factors that could affect patient response. CONCLUSIONS: The present study discovered that adult patients newly diagnosed with ITP who had positive platelet glycoprotein-specific antibody test results were likely to achieve a better response after treatment with HD-DXM + prednisone maintenance.