Circulating reticulated platelets in the early and late phases after ischaemic stroke and transient ischaemic attack.

Abstract

The percentage of reticulated platelets (% RP) could be a useful marker of increased platelet production and/or turnover in patients with increased platelet activation, but few flow cytometric studies have measured the % RP in patients with ischaemic cerebrovascular disease (CVD). Whole blood flow cytometry using thiazole orange was performed to compare the % RP in patients in the early (1-27 d, n = 79) and late phases (79-725 d, n = 70) after ischaemic stroke or transient ischaemic attack (TIA) with controls without CVD (n = 27). The impact of aspirin dose escalation (75-300 mg/d) on the % RP was investigated in 10 patients in the late phase after stroke/TIA. The platelet count and mean platelet volume (MPV) were similar in CVD patients and controls. Compared with controls, the unadjusted % RP was not significantly higher in early or late phase CVD patients (P < or = 0.3). However, having adjusted for age, the % RP was higher in early (P = 0.047) and late phase CVD patients (P = 0.01). There was a positive correlation between % RP and MPV in EDTA- and citrate-anticoagulated blood in both early and late phase CVD patients (P< or = 0.01). The % RP was not significantly influenced by aspirin dose. These data do not convincingly support an excessive stimulus to platelet production in the early or late phases after ischaemic stroke/TIA, but are consistent with the hypothesis that reticulated platelets are larger than more mature 'non-reticulated' platelets in ischaemic CVD.

• Authors: Dominick J H McCabe, Paul Harrison, Paul S Sidhu, Martin M Brown, Samuel J Machin
• Journal: British journal of haematology (Br J Haematol) Vol. 126 Issue 6 Pg. 861-9 (Sep 2004) ISSN: 0007-1048 [Print] England
• PMID: 15352991 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Fibrinolytic Agents
• Platelet Aggregation Inhibitors
• Aspirin

Topics

• Aged
• Aspirin (pharmacology)
• Blood Platelets (drug effects, pathology)
• Brain Ischemia (blood, drug therapy)
• Cell Size
• Dose-Response Relationship, Drug
• Female
• Fibrinolytic Agents (therapeutic use)
• Humans
• Ischemic Attack, Transient (blood, drug therapy)
• Male
• Middle Aged
• Platelet Aggregation Inhibitors (pharmacology)
• Platelet Count
• Stroke (blood, drug therapy)