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Background : Platelet has an important role in hemostasis. This role may depends either on its count or its function. One of the commonly required to evaluate platelet function is the Platelet Aggregation Tests (nephelometric method), but this test is quite expensive at present time and has not been done by many clinical laboratories. Due to this reason, a cheeper platelet function test which requires no special equipment will be investigated by means of peripheral blood smear. Objective : This investigation is intended to introduce another diagnostic value for aggregation function, ie: peripheral blood smear which is more simple, cheaper and applicable in remote rural country medical centres (Puskesmas). In this investigation the sensitivity, specificty, positive and negative predicted value were analysed. Material and method : Adrenalin 3 pM as an inductor for aggregation is added in 3,8% sodium citrate anticoagulated venous blood. Blood smear being made prior to and 3 seconds post adrenalin induction. Evaluation of platelet clumps focused at the medial, lateral and mediolateral areas within zone VI. The number of platelet clumps are compared to the total number of platelets. Velaskar's formula is used to obtain the final results. The results of 65 samples obtained by blood smear are compared to that by the nephelometric method. From the points of Receiver Operator Curve (ROC) show the cut off of hypoaggregation, normoaggregation and hyperaggregation. After identifying the cut off of hypoaggregation-normoaggregation and hyperaggregation-normoaggregation, the diagnostic test is analyzed. Results : The results show that the bottom limit of normoaggregation is 54 % and the highest is 70 %. A diagnostic test of platelet aggregation by blood smear compared to the one by nephelometric method is indicated to determine whether it's hypoaggregation or not, has 73.33 % sensitivity , 86.00 % specificity , 61.11 % positive predicted value and 91.49 % negative predicted value.While the test used to determine normoaggregation or not, has 57.89 % sensitivity, 60.42% specificity, 39.29 % positive predicted value and 78.38 % negative predicted value. To determine hyperaggregation or not, the test has 64.52% sensitvity, 74.29% specificity, 69.97 % positive predicted value and 70.27% negative predicted value. Correlation test of blood smear and nephelometric method has r=0,463; p=0,000 (pc0,01). Paired t test has p=0,357 (p>0,05) Conclusions : The blood smear for platelet aggregation test can be used as a substitution test for the nephelomeiric method. Latar belakang : Trombosit mempunyai peran penting pada pembentukan sumbat hemostasis. Penilaian trombosit meliputi jumlah dan fungsi. Metoda untuk pemeriksaan fungsi agregasi trombosit yang banyak dilakukan saat ini adalah TAT metoda nefelometrik, namun tidak semua laboratorium dapat mengerjakannya. Untuk mengatasi hal tersebut dilakukan percobaan pemeriksaan sediaan apus darah tepi untuk menilai fungsi agregasi trombosit yang dapat dikerjakan di semua laboratorium, tidak memerlukan alat khusus dan murah. Tinian : mengetahui kesesuaian hasil dan nilai diagnostik pemeriksaan sediaan apus darah tepi dibandingkan TAT metoda nefelometrik yang meliputi sensitivitas, spesifisitas, nilai ramal positip dan nilai ramal negatip. Bahan dan metoda : Dilakukan pemeriksaan sediaan apus darah tepi dan TAT metoda nefelometrik dad 65 subyek yang ada. Antikoagulan yang digunakan Natrium citrate 3,8 %. Sediaan apus dibuat sebelum dan setelah 3 menit pemberian induktor adrenalin 3pM Penilaian fungsi agregasi trombosit berdasarkan pembacaan pada zone VI daerah medial, lateral dan mediolateral. Dihitung banyaknya trombosit yang berkelompok dibandingkan total trombosit Hasil yang didapat dimasukkan ke rumus Velaskar. Hasil pemeriksaan sediaan apus dibandingkan dengan hasil TAT metoda nefelometrik dan dicari batas hipoagregasi, normoagregasi dan hiperagregasi dengan bantuan titik-titik kurva ROC. Dad hasil yang didapat dilakukan uji korelasi, uji beda t berpasangan dan uji diagnostik antara pemeriksaan sediaan apus darah tepi dan TAT metoda nefelometrik. Hasil penelitian : Didapatkan hasil batas bawah normoagregasi 54% dan batas atas nonnoagregasi 70%. Pada uji korelasi antara pembaca I dan TAT metoda nefelometrik didapatkan r=0,463; p=0,000 (pc0,01) dan path uji beda t berpasangan didapatkan p=-0,357 (p>0,05). Uji diagnostik pemeriksaan sediaan apus darah tepi dibandingkan TAT metoda nefelometrik untuk menentukan hipoagregasi atan tidak mempunyai sensitivitas 73,33%, spesifisitas 86,00%, nilai ramal positip 61,11% dan nilai ramal negatip 91,49%. Sedang untuk menentukan normoagregasi atau tidak mempunyai sensitivitas 57,89%, spesifisitas 60,42%, nilai ramal positip 39,29% dan nilai ramal negatip 78,38%. Untuk menentukan hiperagregasi atau tidak mempunyai sensitivitas 64,52%, spesifisitas 74,29%, nilai ramal positip 68,97% dan nilai ramal negatip 70,27%. Kesimpulan : Metoda sediaan apus darah tepi dapat dipakai untuk menilai fungsi agregasi trombosit seperti halnya TAT metoda nefelometrik. Kata anal : tes agregasi trombosit, nefelometrik, sediaan apus

Item Type:Thesis (Masters)
Subjects:R Medicine > R Medicine (General)
Divisions:School of Postgraduate (mixed) > Master Program in Biomedical Science
ID Code:14528
Deposited By:Mr UPT Perpus 2
Deposited On:16 Jun 2010 08:10
Last Modified:16 Jun 2010 08:10

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