I am Diabetic Type II, HBA1c around 7, Hypertention for 17 years and CKD patient . S creatinine 1.36
In this link I found some info about egfr
https://ukidney.com/nephrology-resources/egfr-calculator
eGFR is estimated GFR calculated by the abbreviated MDRD equation : 186 x (Creatinine/88.4)-1.154 x (Age)-0.203 x (0.742 if female) x (1.210 if black). If you have an eGFR value calculated by a local laboratory, use that. It is likely to be more accurate than this calculator, which cannot take into account local variations in creatinine measurements.
Stage GFR* Description
1 90+ Normal kidney function but urine findings or structural abnormalities or genetic trait point to kidney disease
2 60-89 Mildly reduced kidney function, and other findings (as for stage 1) point to kidney disease
3A 45-59 Moderately reduced kidney function
3B 30-44
4 15-29 Severely reduced kidney function
5 <15 or on dialysis Very severe, or end-stage kidney failure
Im not a doctor but I think the problem lies on sugar because creatinine indicate the amount of waste products in tbe blood and its very low , but your gfr indicates that your kidney is not functioning well .control your diabetes its the cause of your kidney problems