·To explore the effect of recombinant human granulocyte-macrophage colony stimulating factor (rhGM-CSF) gel on the donor site of patients with diabetic skin ulcer after medium to thickness skin transplantation.

·Seventy-four patients with diabetic skin ulcer who were admitted to the Burn Wound Center, the First Affiliated Hospital of Wenzhou Medical University from March 2016 to April 2021 and underwent medium to thickness skin transplantation were analyzed retrospectively. All patients were given active monitoring, drug control of blood glucose, appropriate symptomatic and supportive treatment such as anti-inflammatory, fluid rehydration and nutrition. According to the different treatment methods of the donor site, patients treated with rhGM-CSF gel in the skin donor sites were assigned to the rhGM-CSF group (38 cases); patients treated with routine dressing change in the skin donor sites were assigned to the control group (36 cases). The healing rate and the complete healing time of the donor site on the 8th and 14th day after treatment were calculated respectively in the two groups, and the changes of laboratory examination results before and after treatment in the rhGM-CSF group were compared.

·There were no significant differences in age, pre-treatment albumin level, glycated hemoglobin level and the area of donor site between the two groups. On the 8th and 14th day after treatment, the wound healing rates of the rhGM-CSF group were (53±19) % and (92±14) %, respectively, which were significantly higher than (35±18) % and (77±20) % of the control group, and the difference was statistically significant (t=-4.159, P=0.000; t=-3.462, P=0.000). The complete healing time of the donor site in the rhGM-CSF group was (14±3) d, which was shorter than (16±3) d in the control group (t=3.452, P=0.000). There was no significant difference in platelet count, the levels of hemoglobin, glutamic-pyruvic transaminase, and creatinine. Leukocyte count after treatment was lower than before treatment (Z=-3.491, P=0.000), but both of them were in the normal reference range and had no clinical significance.

·The application of rhGM-CSF gel to the donor site after medium to thickness skin transplantation in diabetic skin ulcer patients can promote the healing of wounds, shorten the wound healing time, and has certain safety. It is worthy of application and popularization.