Assessment of platelet function analyzer (PFA-100) in kidney transplant patients before renal allograft biopsy: a...

Kidney biopsy (KB) represents the criterion standard to obtain information on diagnosis and prognosis of renal allograft dysfunctions. However, it can be associated with bleeding complications (BCs). Bleeding time test (BTT), the best predictive indicator of post-biopsy BCs, is not a very reproducible test and is invasive. Therefore, the aim of this study was to evaluate whether the platelet function analyzer (PFA-100), a very reliable test to investigate primary hemostasis, could be useful in predicting the risk of bleeding complications in transplant patients undergoing KB.

We carried out a retrospective analysis of PFA-100 collagen-epinephrine (C-EPI) and collagen-adenosine diphosphate (C-ADP) closure times in 119 patients undergoing KB in our center. Data regarding BTT, age, sex, blood pressure, number of renal allograft punctures for each biopsy procedure, thromboplastin time, prothrombin time, complete blood count, and prophylactic therapy with desmopressin were also collected. Major (need for blood transfusion) or minor (no need for any intervention) BCs (hematoma and hematuria) were recorded.

Indications for KB were: delayed graft function (n=23), allograft dysfunction (n=40), proteinuria (n=27), allograft dysfunction plus proteinuria (n=19), and protocol biopsy (n=10). Nine of the 119 patients (7.5%) developed minor BCs (6 macrohematuria, 3 hematoma), major BCs did not develop. No significant differences were found in any of the clinical and laboratory data, including BTT and PFA-100 (C-EPI and C-ADP) between patients who developed BCs compared with those who did not. In addition, there was no correlation between PFA-100 test (C-EPI and C-ADP) values and BTT data [R2=0.002; P=.6].

The PFA-100 test was not useful in predicting the risk of BCs in kidney transplant patients undergoing renal allograft biopsy.