ABSTRACT In Indonesia, dengue virus infection has a high mortality rate. Hemoglobin, hematocrit, leukocyte, differential count, and thrombocyte are laboratory parameters frequently used to monitor patient progress. To study the pattern of hemoglobin, hematocrit, leukocyte, differential count, and thrombocyte based on defervescence in pediatric patient with viral dengue infections. This was a descriptive observational study using medical records at General Hospital Dr. Soetomo Surabaya from February to August 2012. The total sample were 77 pediatric patients in the aged range of 1-18 years old with DF or DHF and according to inclusion and exclusion criteria. The average hemoglobin and hematocrit levels of DHF were higher than DF, both of increased in D0. The average leukocyte count of DF was lower than DHF, both of decreased on D-0. The average lymphocyte count of DHF decreased on D-3, conversely DF continued to increase. The average monocyte count of DHF increased in D-1, then decreased with DF to D+4. The average basophil count of DHF increased in D-0, while DF increased in D+2. The average eosinophil count of DHF increased in D-3. The average neutrophil count of DHF continued to increase in D-3, but was lower in D0, while DD decreased in D+3. The average thrombocyte count of DHF and DD were the lowest on D+3 and D+1. The average hemoglobin and hematocrit levels of DF and DHF increased on D0. The average thrombocyte count of DHF was lower than DF especially on D-1 to D+1. The average leukocyte count of DF and DHF decreased on D-1. The average monocyte, basophil, and eosinophil count of DHF were higher than DF on D0. While the average monocyte and neutrophil count of DHF were lower than DF on D0. Keyword: Dengue, Pediatric Patients, Defervescence , Thrombocyte, Leukocyte, Hemoglobin, Hematocrit ABSTRAK Infeksi virus dengue di Indonesia masih memiliki angka kematian cukup tinggi. Hemoglobin, hematokrit, leukosit, hitung jenis leukosit, dan trombosit sering digunakan untuk memantau perkembangan pasien. Mengetahui pola hemoglobin, hematokrit, leukosit, hitung jenis leukosit, dan trombosit berdasarkan waktu defervescence pada pasien anak infeksi virus dengue. Penelitian deskriptif observasional menggunakan data rekam medik pasien di Instalasi Rawat Inap SMF Anak RSUD Dr. Soetomo Surabaya antara Februari-Agustus tahun 2012. Total sampel adalah 77 pasien anak usia 1-18 tahun dengan DD atau DBD serta memenuhi kriteria inklusi dan eksklusi. Rerata kadar hemoglobin dan hematokrit DBD lebih tinggi dibandingkan DD, keduanya meningkat pada H0. Jumlah leukosit DD lebih rendah dibandingkan DBD, keduanya menurun pada H-1. Rerata jumlah limfosit DBD menurun pada H-3, sebaliknya DD terus meningkat. Rerata jumlah monosit DBD meningkat pada H+1 kemudian menurun dengan DD sampai H+4. Rerata jumlah basofil DBD meningkat pada H0, sebaliknya DD meningkat pada H+2. Rerata jumlah eosinofil DBD meningkat sejak awal demam. Rerata jumlah neutrofil DBD terus meningkat namun lebih rendah pada H0, sedangkan DD menurun pada H+3. Rerata jumlah trombosit DBD dan DD terendah pada H+1 dan H-1. Rerata kadar hemoglobin dan hematokrit DD dan DBD meningkat pada H0. Rerata jumlah trombosit DBD lebih rendah dibandingkan DD terutama pada H-1 sampai H+1. Rerata jumlah leukosit DD dan DBD menurun pada H-1. Rerata jumlah monosit, basofil, dan eosinofil DBD lebih tinggi dibandingkan DD pada H0. sebaliknya jumlah monosit dan neutrofil DBD lebih rendah dibandingkan DD pada H0. Kata Kunci: Dengue, Anak, Defervescence, Trombosit, Leukosit, Hemoglobin, Hematokrit