Diagnostic Value of Tests for Reticulated Platelets, Plasma Glycocalicin, and Thrombopoietin Levels for Discriminating Between Hyperdestructive and Hypoplastic Thrombocytopenia

Abstract

We measured reticulated platelets (RPs) and plasma glycocalicin (GC) and thrombopoietin (TPO) levels simultaneously in 107 thrombocytopenic patients to clarify the diagnostic value of these tests for discriminating hyperdestructive from hypoplastic thrombocytopenia. The percentage of RPs and GC index (plasma GC level normalized for the individual platelet count) were markedly elevated in patients with idiopathic thrombocytopenic purpura (ITP) but normal or slightly elevated in patients with aplastic anemia (AA) or chemotherapy-induced thrombocytopenia (ChemoT). For RP percentage for diagnosing hyperdestructive thrombocytopenia the sensitivity and specificity were excellent but were lower for the GC index. Absolute RP counts and plasma GC levels were markedly decreased and plasma TPO levels markedly elevated in patients with AA or ChemoT, but absolute RP counts and plasma GC levels were moderately decreased and plasma TPO levels only slightly elevated in patients with ITP. The sensitivity and specificity of plasma TPO levels for diagnosing hypoplastic thrombocytopenia were excellent. Using the RP percentage and plasma TPO levels in combination improved specificities. Simultaneous measurement of RP percentage and plasma TPO level may help discriminate thrombocytopenia of unknown cause in routine hematologic practice.

Prolonged thrombocytopenia after allogeneic hematopoietic stem cell transplantation: associations with impaired platelet production and increased platelet turnover

“…The plasma TPO level was comparable between SCT recipients with thrombocytopenia and patients with aplastic anemia, a disease characterized by an extremely high level of TPO. 10,11 The frequency of increased TPO was comparable between SCT recipients with thrombocytopenia and patients with aplastic anemia (70 versus 89%). It was noted that eight (30%) SCT recipients lacking thrombocytopenia also had an elevated TPO level.…”

“…6,7 Recently, measurement of the glycocalicin index (GCI) and circulating thrombopoietin (TPO) has been useful for discriminating increased platelet turnover from impaired platelet production. [8][9][10][11][12] Glycocalicin is a fragment cleaved from the extracellular domain of the plateletspecific glycoprotein (GP) Iba, and its plasma level normalized to the platelet count (referred to as the GCI) has been proposed as a useful parameter for evaluating platelet turnover. 13 The GCI is increased in hyperdestructive states, such as in immune thrombocytopenia.…”

Platelet Turnover and Atherothrombosis

“…Классический пример патологии с ускоренной продукцией и оборотом тромбо-цитов -это иммунная тромбоцитопения (ИТП). Быстро развивающаяся тромбоцитопе-ния, обусловленная высокой скоростью разру-шения сенсибилизированных аутоантитела-ми тромбоцитов, приводит к компенсаторно-му увеличению их продукции и появлению в крови более крупных тромбоцитов (повыше-ние СОТ) и повышению содержания ретику-лярных форм [16][17][18][19][20]. В частности, в нашем исследовании [20] мы показали, что у больных с ИТП наблюдается повышение СОТ более чем на 20% по сравнению со здоровыми доно-рами -9,6 ± 1,7 фл (n = 107) и 7,9 ± 1,0 фл (n = 38), p < 0,001.…”

“…Для такого стабильного по-казателя, как СОТ, такие изменения являются очень существенными. Количество ретикуляр-ных тромбоцитов при ИТП может увеличи-ваться более чем в 2 раза, достигая значений в 20-30% от общего числа циркулирующих тромбоцитов [16][17][18]. Похожие изменения фенотипа тромбоцитов (хотя и менее выра-женные) могут происходить при крупных кровопотерях и при некоторых вариантах тромбоцитозов (в частности, реактивных формах, ассоциированных с наличием воспа-лительного процесса) [15].…”

Ativação plaquetária na esclerose sistêmica e alternativas metodológicas para sua avaliação

“…A glicocalicina (55) , fragmento proteolítico da gpIb, pode ser facilmente medida por ELISA (78) . Níveis séricos elevados desse marcador estão presentes na púrpura trombocitopênica idiopática (79) e na trombocitopenia da infecção por HIV (78) . Níveis plasmáticos normais têm sido relatados em pacientes com hipoplasia de medula óssea e baixos níveis são encontrados no sangue venoso umbilical (80) .…”