Brief Answer:
Depends on many other factors
Detailed Answer:
Hello, I'm Dr. Branch, thanks for using Ask a Doctor. Stage 2 kidney disease according to glomerular filtration rate (GFR) means you would have a GFR between 60 to 89. How serious this is depends on many factors, including whether your GFR has been steadily decreasing, and what the cause might be, for which we would want to look at your blood pressure, urinalysis, and consider your age. The GFR is based on your creatinine, so sometimes there are temporary causes of an increase in your creatinine, which could be from dehydration or medications.
So, if you'd like to send me more information, including your age and sex, any lab results concerning your kidney function (including creatinine and any urinalysis results), what other medical problems you have, what medications you take, I should be able to give a more clear idea of how serious your kidney results are.
Thank you for your question and I look forward to your response.