Results
A total of 86 patients were enrolled, 12.8% (11/86 cases) patients were
classified into the mild-moderate group, and 87.2% (75/86 cases)
patients were classified into the severe group. There was no statistical
difference in gender (χ2 =0.292, P =0.589)
and age (Z =-0.770, P =0.442) between the two bleeding
severity groups. The positive rate of platelet-specific antibodies was
73.3% (63/86). The positive rates of anti-GPIIb/IIIa and anti-GPIb/IX
antibodies were 68.6% (59/86) and 65.1% (56/86), respectively. Details
of baseline characteristics and different platelet-specific antibody
types are shown in TABLE 1.
The respective distribution of anti-GPIIb/IIIa and anti-GPIb/IX
antibodies in the two bleeding severity groups are shown in TABLE 2.
There was no significant difference in the distribution of
anti-GPIIb/IIIa (χ2 =0.530, P =0.467) and
anti-GPIb/IX antibodies (χ2 <0.001,P =1.000) between the two bleeding severity groups.
The comprehensive distribution of anti-GPIIb/IIIa and anti-GPIb/IX
antibodies in the two bleeding severity groups is shown in TABLE 3 and
Fig. 1. There was no significant
difference in the distribution of four different antibody combinations
between the two bleeding severity groups
(χ2 =2.071, P =0.558). We also analyzed
the differences between any two of four different antibody combinations
with the Chi-square test or Fisher’s exact test but did not find any
significant difference (Fig. 1).
The antibody titer ratios of anti-GPIIb/IIIa and anti-GPIb/IX antibodies
in plasma and eluent between the two bleeding severity groups are shown
in Fig. 2. We found that the anti-GPIIb/IIIa antibody titer ratios in
eluent were significantly higher than those in plasma (Z =-5.556,P <0.001), and the same was with anti-GPIb/IX antibody
(Z =-5.862, P <0.001). Al-Samkari et al.11 reported that direct assays for platelet-specific
antibodies on platelets, as opposed to indirect assays, which measured
free antibodies in plasma, had higher sensitivity and specificity and
were considered optimal for platelet-specific antibodies testing. Our
results were consistent with this study result. However, we found no
significant difference in antibody titer ratios between the two bleeding
severity groups in both plasma and eluent (anti-GPIIb/IIIa antibody in
plasma: Z =-0.601, P =0.548; anti-GPIIb/IIIa antibody in
eluent: Z =-0.556, P =0.578; anti-GPIb/IX antibody in
plasma: Z =-0.388, P =0.698; anti-GPIb/IX antibody in
eluent: Z =-0.175, P =0.861).