Effects of granulocyte-colony stimulating factor in the treatment of diabetic foot infection

Aims: Foot infections and the subsequent amputation of a lower extremity are the most common cause of hospitalization among patients with diabetes mellitus. Although there are several reasons for susceptibility to infection in diabetic patients, white blood cell dysfunction is considered to be an important cause for this tendency. Granulocyte-colony stimulating factor (G-CSF) increases the release of neutrophils from the bone marrow and improves neutrophil functions. Based on this knowledge, the aim of the present study was to investigate the effects of addition of G-CSF to the treatment of foot infections in diabetic patients. Methods: Thirty diabetic patients with foot infection were included in the study. Fifteen of the patients received standard treatment consisting of local wound care and antibiotics (standard goup), and the other 15 patients received G-CSF besides standard treatment (G-CSF group). The objectives of this study were to determine the time to resolution of infection, time to hospital discharge, need for surgical intervention, and the effects of G-CSF on phagocytosis and respiratory burst of neutrophils. Results: Treatment with G-CSF led to significantly higher neutrophil counts on the 5th and loth days, and at the end of treatment in the G-CSF treated group compared to the standard group. Respiratory burst of neutrophils increased significantly in both the G-CSF group (from 1.6 +/-0.3 to 2.3 +/-0.5. p=0.001) and the standard group (from 2.0 +/-0.4 to 2.3 +/-0.4, p=0.02) with treatment. But, while phagocytosis of neutrophils increased significantly in the G-CSF group (from 70.4 +/-2.0 to 74.5 +/-1.9, p=0.004), it did not change significantly in the standard group (from 68.1 +/-0.2 to 69.4 +/-1.9, p=0.3) with treatment. Duration of hospitalization (26.9 +/-2.0 vs. 28.3 days, p<0.05), duration of parenteral antibiotic administration (22.9<plus/minus>2.0 vs. 23.3 +/-1.9 days, p<0.05), time to resolution of infection (23.6<plus/minus>1.8 vs. 22.3 +/-1.7 days, p<0.05), and need for amputation (13.3% vs. 20%, p>0.05) were similar between the G-CSF and the standard groups. Conclusions: Although G-CSF improves neutrophil function as well as increasing the absolute numbers, this improvement is not associated with shortening of duration of antibiotic administration, duration of hospital stay or need for amputation in diabetic foot infection.