KDIGO 2012 Clinical Practice Guideline for the Evaluation and Management of Chronic Kidney Disease

KDIGO 2022 Clinical Practice Guideline for Diabetes Management in Chronic Kidney Disease

Levey AS, Stevens LA, Schmid CH, et al. A new equation to estimate glomerular filtration rate. Ann Intern Med. 2009;150(9):604-12.

Inker LA, Schmid CH, Tighiouart H, et al. Estimating glomerular filtration rate from serum creatinine and cystatin C. N Engl J Med. 2012;367(1):20-9.

Inker LA, Eneanya ND, Coresh J, et al. New creatinine- and cystatin c-based equations to estimate gfr without race. N Engl J Med. Published online September 23, 2021.

Dr. Andrew S. Levey

Dr. Lesley A. Inker

The CKD Epidemiology Collaboration (CKD-EPI)

//outputs
var calc_output = [];

//user inputs
var gender = parseFloat(gender);
var race = parseFloat(race) || 0;
var age = parseFloat(age);
var calc = parseFloat(calc);
var scr = parseFloat(scr);
var scys = parseFloat(scys);

if (UOMSYSTEM == false) {
	scr = scr / 88.4;
}

//calculation for CDK-EPI Creatinine
if(calc == 0){
	var u_cr;
	if(gender == 0){			//if female
		if(scr <= 0.7){
			u_cr = 144 * Math.pow(scr/0.7, -0.329) * Math.pow(0.993, age); 
		}else{
			u_cr = 144 * Math.pow(scr/0.7, -1.209) * Math.pow(0.993, age); 
		}
	}else{					//if male
		if (scr <= 0.9){
			u_cr = 141 * Math.pow(scr/0.9, -0.411) * Math.pow(0.993, age); 
		}else{
			u_cr = 141 * Math.pow(scr/0.9, -1.209) * Math.pow(0.993, age); 
		}
	}

	if(race == 1){  //patient is black
		u_cr = u_cr * 1.159;
	} else if(race == 0){  //patient is black
		var u_cr_range = u_cr * 1.159;
      u_cr_range = u_cr_range.toFixed(0);
	} 
	var stage;
	u_cr = u_cr.toFixed(0);
if (u_cr >= 90) {
	stage = 'Stage I';
}
else if (u_cr >= 60 && u_cr < 90) {
	stage = 'Stage II';
}
else if (u_cr >= 30 && u_cr < 60) {
		if (u_cr >= 30 && u_cr < 45){
          stage = 'Stage IIIb';
        } else {
          stage = 'Stage IIIa';
        }
}
else if (u_cr >= 15 && u_cr < 30) {
	stage = 'Stage IV';
}
else {
	stage = 'Stage V';
}

if (race == 0) {
	var stage_range;
	if (u_cr_range >= 90) {
	stage_range = 'Stage I';
}
else if (u_cr_range >= 60 && u_cr_range < 90) {
	stage_range = 'Stage II';
}
else if (u_cr_range >= 30 && u_cr_range < 60) {
		if (u_cr_range >= 30 && u_cr_range < 45){
          stage_range = 'Stage IIIb';
        } else {
          stage_range = 'Stage IIIa';
        }
}
else if (u_cr_range >= 15 && u_cr_range < 30) {
	stage_range = 'Stage IV';
}
else {
	stage_range = 'Stage V';
}
if (stage != stage_range) {
		stage = stage_range+'-'+stage;
	}
}
}
//calculation for CDK-EPI Cystatin C
if(calc == 1){
	var u_cys;
	if(scys <= 0.8){
		u_cys = 133 * Math.pow(scys/0.8, -0.499) * Math.pow(0.996, age);
	}else{
		u_cys = 133 * Math.pow(scys/0.8, -1.328) * Math.pow(0.996, age);
	}
	if(gender == 0){		//if patient is female
		u_cys = u_cys * 0.932;
	}
	var stage;
	u_cys = u_cys.toFixed(0);
	if (u_cys >= 90) {
		stage = 'Stage I';
	}
	else if (u_cys >= 60 && u_cys < 90) {
		stage = 'Stage II';
	}
  	else if (u_cys >= 30 && u_cys < 60) {
		if (u_cys >= 30 && u_cys < 45){
          stage = 'Stage IIIb';
        } else {
          stage = 'Stage IIIa';
        }
  	}
	else if (u_cys >= 15 && u_cys < 30) {
		stage = 'Stage IV';
	}
	else {
		stage = 'Stage V';
	}
}

//calculation for CKD-EPI Creatinine Cystatin C
if(calc == 2){
	var u_both;
	if(gender == 0){			//if female
		if(scr <= 0.7){
			if (scys <=0.8){
				u_both = 130 * Math.pow(scr/0.7, -0.248) * Math.pow(scys/0.8, -0.375) * Math.pow(0.995, age);
			}else{
				u_both = 130 * Math.pow(scr/0.7, -0.248) * Math.pow(scys/0.8, -0.711) * Math.pow(0.995, age);
			}
		}else{
			if (scys <=0.8){
				u_both = 130 * Math.pow(scr/0.7, -0.601) * Math.pow(scys/0.8, -0.375) * Math.pow(0.995, age);
			}else{
				u_both = 130 * Math.pow(scr/0.7, -0.601) * Math.pow(scys/0.8, -0.711) * Math.pow(0.995, age);
			}
		}
	}else{						//if male
		if(scr <= 0.9){
			if (scys <=0.8){
				u_both = 135 * Math.pow(scr/0.9, -0.207) * Math.pow(scys/0.8, -0.375) * Math.pow(0.995, age);
			}else{
				u_both = 135 * Math.pow(scr/0.9, -0.207) * Math.pow(scys/0.8, -0.711) * Math.pow(0.995, age);
			}
		}else{
			if (scys <=0.8){
				u_both = 135 * Math.pow(scr/0.9, -0.601) * Math.pow(scys/0.8, -0.375) * Math.pow(0.995, age);
			}else{
				u_both = 135 * Math.pow(scr/0.9, -0.601) * Math.pow(scys/0.8, -0.711) * Math.pow(0.995, age);
			}
		}
	}

	if(race == 1){  //patient is black
		u_both = u_both * 1.08;
	} if(race == 0){  //patient is black
		var u_both_range = u_both * 1.08;
      u_both_range = u_both_range.toFixed(0);
	} 
var stage;
	u_both = u_both.toFixed(0);
	if (u_both >= 90) {
	stage = 'Stage I';
	}
	else if (u_both >= 60 && u_both < 90) {
		stage = 'Stage II';
	}
	else if (u_both >= 30 && u_both < 60) {
		if (u_both >= 30 && u_both < 45){
          stage = 'Stage IIIb';
        } else {
          stage = 'Stage IIIa';
        }
    }
	else if (u_both >= 15 && u_both < 30) {
		stage = 'Stage IV';
	}
	else {
		stage = 'Stage V';
	}
	if (race == 0) {
		var stage_range;
		if (u_both_range >= 90) {
		stage_range = 'Stage I';
		}
		else if (u_both_range >= 60 && u_both_range < 90) {
			stage_range = 'Stage II';
		}
		else if (u_both_range >= 30 && u_both_range < 60) {
			if (u_both_range >= 30 && u_both_range < 45){
	          stage_range = 'Stage IIIb';
	        } else {
	          stage_range = 'Stage IIIa';
	        }
	    }
		else if (u_both_range >= 15 && u_both_range < 30) {
			stage_range = 'Stage IV';
		}
		else {
			stage_range = 'Stage V';
		}
	if (stage != stage_range) {
		stage = stage_range+'-'+stage;
	}
	}
}

if(calc == 3){
var u_cr;
	if(gender == 0){			//if female
		if(scr <= 0.7){
			u_cr = 142 * Math.pow(scr/0.7, -0.241) * Math.pow(0.9938, age) * 1.012; 
		}if(scr > 0.7){
			u_cr = 142 * Math.pow(scr/0.7, -1.2) * Math.pow(0.9938, age) * 1.012; 
		}
	}
	if(gender == 1){      //if male
	if(scr <= 0.9){
			u_cr = 142 * Math.pow(scr/0.9, -0.302) * Math.pow(0.9938, age); 
		}if(scr > 0.9){
			u_cr = 142 * Math.pow(scr/0.9, -1.2) * Math.pow(0.9938, age); 
		}
	}
	var stage;
	u_cr = u_cr.toFixed(0);
	if (u_cr >= 90) {
		stage = 'Stage I';
	}
	else if (u_cr >= 60 && u_cr < 90) {
		stage = 'Stage II';
	}
	else if (u_cr >= 30 && u_cr < 60) {
			if (u_cr >= 30 && u_cr < 45){
	          stage = 'Stage IIIb';
	        } else {
	          stage = 'Stage IIIa';
	        }
	}
	else if (u_cr >= 15 && u_cr < 30) {
		stage = 'Stage IV';
	}
	else {
		stage = 'Stage V';
	}
}

//calculation for CKD-EPI Creatinine Cystatin C
if(calc == 4){
var u_cys;
	if(gender == 0){			//if female
		if(scr <= 0.7){
			if(scys <= 0.8){
			u_cys = 135 * Math.pow(scr/0.7, -0.219) * Math.pow(scys/0.8, -0.323) * Math.pow(0.9961, age) * 0.963;
			}
			if(scys > 0.8){
			u_cys = 135 * Math.pow(scr/0.7, -0.219) * Math.pow(scys/0.8, -0.778) * Math.pow(0.9961, age) * 0.963;
			}
		}if(scr > 0.7){
			if(scys <= 0.8){
			u_cys = 135 * Math.pow(scr/0.7, -0.544) * Math.pow(scys/0.8, -0.323) * Math.pow(0.9961, age) * 0.963;
			}
			if(scys > 0.8){
			u_cys = 135 * Math.pow(scr/0.7, -0.544) * Math.pow(scys/0.8, -0.778) * Math.pow(0.9961, age) * 0.963;
			}
		}
    }
	if(gender == 1){      //if male
		if(scr <= 0.9){
			if(scys <= 0.8){
			u_cys = 135 * Math.pow(scr/0.9, -0.144) * Math.pow(scys/0.8, -0.323) * Math.pow(0.9961, age);
			}
			if(scys > 0.8){
			u_cys = 135 * Math.pow(scr/0.9, -0.144) * Math.pow(scys/0.8, -0.778) * Math.pow(0.9961, age);
			}
		}if(scr > 0.9){
			if(scys <= 0.8){
			u_cys = 135 * Math.pow(scr/0.9, -0.544) * Math.pow(scys/0.8, -0.323) * Math.pow(0.9961, age);
			}
			if(scys > 0.8){
			u_cys = 135 * Math.pow(scr/0.9, -0.544) * Math.pow(scys/0.8, -0.778) * Math.pow(0.9961, age);
			}
		}
	}
	var stage;
	u_cys = u_cys.toFixed(0);
	if (u_cys >= 90) {
		stage = 'Stage I';
	}
	else if (u_cys >= 60 && u_cys < 90) {
		stage = 'Stage II';
	}
  	else if (u_cys >= 30 && u_cys < 60) {
		if (u_cys >= 30 && u_cys < 45){
          stage = 'Stage IIIb';
        } else {
          stage = 'Stage IIIa';
        }
  	}
	else if (u_cys >= 15 && u_cys < 30) {
		stage = 'Stage IV';
	}
	else {
		stage = 'Stage V';
	}

}

//result for user
if(calc ==0 && race != 0){
	calc_output.push({
	name: 'mini',
	value: u_cr,
	value_text: 'ml/min/1.73 m\u00B2',
	message: 'GFR'
	});
	calc_output.push({
	name: '3939_CKD-EPI Equations for GFR_result (creatinine)',
	value: u_cr,
	value_text: 'ml/min/1.73 m\u00B2',
	message: 'Estimated GFR by CKD-EPI Creatinine'
	});
	calc_output.push({
	name: '3939_CKD-EPI Equations for GFR_result (stage)',
	value: stage,
	value_text: '',
	message: 'CKD stage by CKD-EPI Creatinine'
	});
}
if(calc ==0 && race == 0){
	calc_output.push({
	name: 'mini',
	value: u_cr + "-" + u_cr_range,
	value_text: 'ml/min/1.73 m\u00B2',
	message: 'GFR'
	});
	calc_output.push({
	name: '3939_CKD-EPI Equations for GFR_result (creatinine)',
	value: u_cr + "-" + u_cr_range,
	value_text: 'ml/min/1.73 m\u00B2',
	message: 'Estimated GFR by CKD-EPI Creatinine'
	});
	calc_output.push({
	name: '3939_CKD-EPI Equations for GFR_result (stage)',
	value: stage,
	value_text: '',
	message: 'CKD stage by CKD-EPI Creatinine'
	});
}
if(calc ==1){
	calc_output.push({
	name: 'mini',
	value: u_cys,
	value_text: 'ml/min/1.73 m\u00B2',
	message: 'GFR'
	});
	calc_output.push({
	name: '3939_CKD-EPI Equations for GFR_result (cystatin)',
	value: u_cys,
	value_text: 'ml/min/1.73 m\u00B2',
	message: 'Estimated GFR by CKD-EPI Cystatin C'
	});
	calc_output.push({
	name: '3939_CKD-EPI Equations for GFR_result (stage)',
	value: stage,
	value_text: '',
	message: 'CKD stage by CKD-EPI Creatinine'
	});
}
if (calc ==2 && race != 0){
	calc_output.push({
	name: 'mini',
	value: u_both,
	value_text: 'ml/min/1.73 m\u00B2',
	message: 'GFR'
	});
	calc_output.push({
	name: '3939_CKD-EPI Equations for GFR_result (creatinine-cys)',
	value: u_both,
	value_text: 'ml/min/1.73 m\u00B2',
	message: 'Estimated GFR by CKD-EPI Creatinine-Cystatin C'
	});
	calc_output.push({
	name: '3939_CKD-EPI Equations for GFR_result (stage)',
	value: stage,
	value_text: '',
	message: 'CKD stage by CKD-EPI Creatinine'
	});
}
if (calc ==2 && race == 0){
	calc_output.push({
	name: 'mini',
	value: u_both + "-" + u_both_range,
	value_text: 'ml/min/1.73 m\u00B2',
	message: 'GFR'
	});
	calc_output.push({
	name: '3939_CKD-EPI Equations for GFR_result (creatinine-cys)',
	value: u_both + "-" + u_both_range,
	value_text: 'ml/min/1.73 m\u00B2',
	message: 'Estimated GFR by CKD-EPI Creatinine-Cystatin C'
	});
	calc_output.push({
	name: '3939_CKD-EPI Equations for GFR_result (stage)',
	value: stage,
	value_text: '',
	message: 'CKD stage by CKD-EPI Creatinine'
	});
}
if(calc == 3){
	calc_output.push({
	name: 'mini',
	value: u_cr,
	value_text: 'ml/min/1.73 m\u00B2',
	message: 'GFR'
	});
	calc_output.push({
	name: '3939_CKD-EPI Equations for GFR_result (creatinine)',
	value: u_cr,
	value_text: 'ml/min/1.73 m\u00B2',
	message: 'Estimated GFR by 2021 CKD-EPI Creatinine'
	});
	calc_output.push({
	name: '3939_CKD-EPI Equations for GFR_result (stage)',
	value: stage,
	value_text: '',
	message: 'CKD stage by CKD-EPI Creatinine'
	});
}
if(calc == 4){
	calc_output.push({
	name: 'mini',
	value: u_cys,
	value_text: 'ml/min/1.73 m\u00B2',
	message: 'GFR'
	});
	calc_output.push({
	name: '3939_CKD-EPI Equations for GFR_result (cystatin)',
	value: u_cys,
	value_text: 'ml/min/1.73 m\u00B2',
	message: 'Estimated GFR by 2021 CKD-EPI Creatinine-Cystatin C'
	});
	calc_output.push({
	name: '3939_CKD-EPI Equations for GFR_result (stage)',
	value: stage,
	value_text: '',
	message: 'CKD stage by CKD-EPI Creatinine'
	});
}


CKD-EPI Equations for Glomerular Filtration Rate (GFR)

calc

gender

scys

race

<p>Estimates GFR based on serum creatinine, serum cystatin C, or both.</p>

CKD-EPI Equations for GFR

<p>Evan Zeitler, MD, is a nephrology fellow at UNC Chapel Hill in North Carolina. He has spent his medical career at UNC, completing medical school, residency, and a nephrology fellowship there. He is passionate about medical education, chronic kidney disease, and acid-base disorders. Dr. Zeitler's primary research is focused on obesity and its downstream effects on kidney metabolism and health.</p>

Evan Zeitler, MD

Omar Aziz, MD

The CKD-EPI Creatinine Equation for Glomerular Filtration Rate (GFR) estimates GFR based on serum creatinine.

Creatinine

Serum cystatin C

MDRD GFR Equation

Kidney Failure Risk Calculator

Kinetic Estimated Glomerular Filtration Rate (keGFR)

EB Medicine is the premier provider of evidence-based clinical content and CME resources for emergency medicine practitioners.

Listen to the VACO co-creators break down how to use VACO\, what it does\, and what it doesn’t.

Calc Function