THE ASSOCIATION OF RETICULATED THROMBOCYTE COUNT WITH TREATMENT RESPONSE IN PATIENTS WITH IDIOPATHIC THROMBOCYTOPENIC PURPURA

Abstract

Objective: Idiopathic thrombocytopenic purpura (ITP) causes thrombocytopenia via the premature destruction of autoantibody covered thrombocytes. It is diagnosed by exclusion of other diseases which cause thrombocytopenia. Reticulothrombocytes (RT) are young thrombocytes containing messenger ribonucleic acid (mRNA) and ribosomal ribonucleic acid (rRNA). Measurement of RT with flow cytometry is reported to reflect thrombopoetic activity in thrombocytopenic patients. The aim of this study is to measure the percentage and absolute number of RT’s in newly diagnosed and refractory ITP patients and to investigate the association between RT percentage and number with response to treatment. Material and Method: The study group consisted of 16 former ITP patients who were refractory to various treatments, 15 newly diagnosed patients and 20 healthy controls. Thrombocyte counts and mean thrombocyte volume were measured with blood count. RT counts were measured via flow cytometry. Reticulocyte counts of the refractory patients, new patients and healthy controls were compared to each other. Results: Thirty five (68.6%) of the 51 patients were female. The patients were between 25 and 75 years old with a mean age of 39.15 years and standard deviation of 13.04 years. The refractory ITP patients and newly diagnosed ITP patients were grouped into Group 1 (n=16) and Group 2 (n=15) respectively. The control group was referred to as Group 3 (n=20). The platelet count of Group 3 was found to be significantly higher than the platelet counts of Groups 1 and 2 (p:0.001) and there was no difference between Groups 1 and 2. The RT percentage was found 21.7% in Group 1, 36.2% in Group 2 and 3.2% in Group 3. The RT percentage of Group 3 was calculated to be significantly lower than the RT percentages of Groups 1 and 2 (p:0.001). There was no difference between Groups 1 and 2. The absolute RT count was insignificant between all groups. Conclusion: The RT percentage count was not statistically different between refractory and newly diagnosed ITP patients. This finding indicates that RT percentage measurement is not helpful in the evaluation of the response to the treatment. The finding of a high RT percentage count in refractory patients suggests that the medical treatment should be continued. 

Keywords

• Flow cytometry,idiopathic thrombocytopenic purpura,reticulated thrombocytes

İDİYOPATİK TROMBOSİTOPENİK PURPURALI HASTALARDA RETİKÜLOTROMBOSİT SAYISININ TEDAVİ CEVABI İLE İLİŞKİSİ

Abstract

Amaç: İdiyopatik trombositopenik purpura (İTP) otoantikorlar ile kaplanmış trombositlerin yıkımı sonucunda trombositopeni oluşumuna sebep olur. Retikülotrombositler (RT) rezidüel, mesajcı ribonükleik asit (mRNA) ve ribosomal ribonükleik asit (rRNA) içeren genç trombositlerdir. Retikülotrombositlerin ölçümü İTP’li ve diğer trombositopenik hastalarda trombopoetik aktivite ile ilişkili bilgi verir. Bu çalışmada, yeni tanı konan ve refrakter İTP’li hastalarda RT yüzdesinin ve mutlak sayısının belirlenmesi ve tedavi cevabı ile ilişkisinin araştırılması amaçlandı. Gereç ve Yöntem: Çalışma, çeşitli tedavilere refrakter 16 hasta, yeni tanı konan 15 hasta ve 20 sağlıklı kontrol ile yapıldı. Trombosit sayısı ve ortalama trombosit hacmi belirlendi. RT’ler akım sitometrik yöntem ile ölçüldü. Bulgular: Olguların 35’i (%68,6) kadın, 16’sı (%31,4) erkekti. Olguların yaşları 20-75 arasında değişmekte olup ortalama 39,15± 13,04’tü. Refrakter hastalar “Grup 1” (n=16), yeni tanılı hastalar “Grup 2” (n=15) ve kontrol grubu olguları “Grup 3” (n=20) olarak adlandırıldı. Retikülotrombositler yüzdesi Grup 1’de %21,7, Grup 2’de %36,2 ve Grup 3’te %3,2 bulundu. Grup 3 ile Grup 1 ve 2 arasında anlamlı fark bulundu (p:0,001). Mutlak RT sayıları açısından anlamlı fark bulunmadı. Sonuç: Retikülotrombosit yüzdesi ölçümü ile, refrakter ve yeni tanılı İTP hastaları arasında fark saptanmamıştır. Retikülotrombosit yüzdesi ölçümünün tedaviye yanıtı göstermediği sonucuna varılmıştır. Refrakter hastalarda RT yüzdesinin yüksek bulunması tedaviye devam edilmesi gerektiğini gösterebilir.

Keywords

• Akım sitometrisi,idiyopatik trombositopenik purpura,retikülotrombosit

Supporting Institution

Bu çalışma İstanbul Tıp Fakültesi Bilimsel Araştırma ve Proje Birimi tarafından desteklenmiştir.

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