Serum complement 3 (C3) and complement 4 (C4) level in febrile neutropenia patients at Dr. Kariadi Hospital, Semarang and Dr. Moewardi Hospital, Surakarta

to identify the serum complement 3 (C3) and complement 4 (C4) level in febrile neutropenia and non-febrile neutropenia patients. this is a cross-sectional prospective study. Samples were collected from patients with febrile neutropenia as sample group and patients with neutropenia but without fever as control. Both groups were tested for serum complement 3 and complement 4 level, and the data were analyzed using student T-test. from 37 neutropenia patients, 23 were classified as febrile neutropenia group and 14 in non-febrile neutropenia as control group. Total mean neutrophil count was 653.22/ml serum in sample group and 594.36/ml serum in control group (p=0.575). Mean C3 level was 95.74 ug/dl in sample group and 130.00 ug/dl in control group, showing significant difference with p=0.031. The mean serum C4 level was 34.13 ug/ml in sample group and 34.00 ug/dl in control group, the difference is not significant with p=0.98. When sample C3 and C4 data were combined, the total level was 125.61 ug/ml, which was significantly lower than the total C3 and C4 in control group 184.07 ug/dl. (p=0.04). in febrile neutropenia there is significant decrease of serum C3 level compared to non-febrile neutropenia. Serum C4 level in febrile neutropenia group is lower than the non-febrile neutropenia group, but the difference is not significant.