A Retrospective Analysis of ADAMTS13 Enzymatic Activity Results in a Population With Thrombotic Thrombocytopenic Purpura Disease in the Arabian Gulf and Colombia (APOLO Study)

TL;DR

This study analyzed ADAMTS13 enzyme activity in TTP patients from the Arabian Gulf and Colombia, finding significant regional differences in result turnaround times.

Contribution

The study provides new insights into ADAMTS13 activity levels and diagnostic delays in TTP patients from two distinct geographic regions.

Findings

Severe ADAMTS13 deficiency (<10%) was found in 23.3% of samples, indicating TTP.

Turnaround time for results was significantly longer in the Arabian Gulf compared to Colombia.

The median age of TTP patients in the study was 39 years, consistent with global reports.

Abstract

Little is known about the thrombospondin type-1 motif, member 13 (ADAMTS-13) enzymatic activity in subjects with suspected/confirmed thrombotic thrombocytopenic purpura (TTP) in the Arabian Gulf and Colombia. The retrospective analysis of ADAMTS13 enzymatic activity results in a population with thrombotic thrombocytopenic purpura disease in the Arabian Gulf and Colombia (APOLO study) aimed to report on ADAMTS-13 enzymatic activity, subject demographics, and the turnaround time for results. This study used laboratory analyses of ADAMTS-13 enzymatic activity in blood samples from subjects with suspected/confirmed TTP in the Arabian Gulf (N=235) and in Colombia (N=155). The primary objective was to report ADAMTS-13 enzymatic activity levels and distribution in categories: severe deficiency <10% (TTP diagnosis), borderline activity 10-20%, and no deficiency >20%. Descriptive statistics were performed using SAS 9.4 (SAS Institute Inc., North Carolina, USA). Among the 390 samples, the average ADAMTS-13 activity level was 42.8%±31.1. Severe deficiency (ADAMTS-13 activity <10%, 1.7%±1.9, indicative of TTP) was found in 91 samples (23.3%) and borderline ADAMTS-13 activity (15.4%±3.0) in 17 (4.4%) samples. The median age among subjects with TTP was 39 years. The average turnaround time for results was 4.4±5.9 days, with a median of 2.0 days. The average turnaround time was significantly longer for samples from the Arabian Gulf (6.5±6.9 days) compared to those from Colombia (1.2±0.8 days, Wilcoxon/Mann-Whitney W-value=18507.5, P<0.001). In conclusion, the median age of subjects with TTP in this study matched the age reported in the literature. The turnaround time is a global concern, as it can lead to delayed confirmatory results and potentially life-saving treatment. In Colombia, the turnaround time considerably benefits TTP management, underscoring the necessity to determine reasons behind occasional result turnaround delays in the Arabian Gulf.

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