PoCT for the Early Detection of Acute Kidney Injury

PoCT for the Early Detection of Acute Kidney Injury

Dr. Gustavo F Méndez Machado MD MSC FESC

Cardiología / Fellow of the European Society of Cardiology

Sub-Director Médico [Nocturno L-M-V]

Hospital General de Zona No 11 Xalapa IMSS

Evolución en el Diagnóstico Cardiaco y

Renal

The renal testing arena is in need of the introduction of novel, early and more sensitive and specific biomarkers

AMI WBC count LDH, SGOT, SGPT CPK CK - MB Troponin -T Troponin - I AKI

Change in serum creatinine

Change in serum creatinine

No

Chan

ge

Time

Conger JD, Am J Kidney Dis 26:565-576, 1995. Star RA, Kidney Int 54:1817-1831, 1998.

3

Daño renal agudo (AKI)



AKI, anteriormente denominado

insuficiencia renal aguda, es comun

– Definicion de AKI es subjectiva y condiciona dificultades en la detecion y diagnostico



La disminucion subita de la funcion renal

condiciona la acumulacion de los

desechos nitrogenados, tales como el

nitrogeno ureico, urea y creatinina



La nomenclatura de AKI describe

condiciones con daño estructural y

disfuncion

Devarajan P. J Am Soc Nephrol. 2006;17:1503-1520. Ricci Z, Ronco C. Crit Care. 2008;12:230-236.

4

Daño Renal Agudo (AKI):

Incidencia y Prevalencia



Incidencia de 1% a 25% en países

desarrollados

– Incidencia de terapia de reemplazo renal (RRT) entre 3.4% a 4.9%

– Mortalidad Hospitalaria secundaria a falla

renal aguda severa con necesidad de terapia de reemplazo 60 al 70% en varios países.



Prevalencia en la Terapia Intensiva (ICU)

– 5% to 6% requieren RRT en ICU

– Mortalidad General en pacientes con AKI de hasta 60.3%

Uchino S. Curr Opin Crit Care. 2006:12:538-543. Uchino S, et al. JAMA. 2005;294:813-818.

5

Factores que contribuyen a la Falla Renal

Aguda

6

Age-Adjusted Hospitalization Rates for

Kidney Disease by Type of Kidney Failure

(1980-2005)

MMWR Morb Mortal Wkly Rep. 2008;57:309-312.

Rate of hospitalization from ARF increased from 1.8 per 10,000 population in 1980 to 36.5 in 2005

7

Mortality in Acute Renal Failure

No ARF ARF 0% 25% 50% 75% M ort al it y

ARF is an independent risk factor for death

Star RA, Kidney Int 54:1817-1831, 1998.

7%

8

RIFLE Criteria for Defining Acute Renal

Failure

Bellomo R, et al. Crit Care. 2004;8:R204-R212. ARF, acute renal failure; GFR, glomerular filtration rate; SCr, serum creatinine

*With an acute rise >0.5 mg/dL

GFR Criteria Urine Output Criteria

Increased SCr x 1.5 or GFR decrease >25% <0.5 mL/kg/h x 6 h Increased SCr x 2 or GFR decrease >50% <0.5 mL/kg/h x 12 h Increased SCr x 3 GFR decrease 75% or SCr ≥4 mg/dL* <0.3 mL/kg/h x 24 h or anuria x 12 hours Persistent ARF = complete loss

of kidney function >4 weeks End stage kidney disease

(>3 months) Risk Injury Failure Loss ESKD High Sensitivity High Specificity

9

Acute Kidney Injury Network Criteria

for the Definition and Classification of AKI

RRT, renal replacement therapy; SCr, serum creatinine

Stage SCr Criteria Urine Output Criteria Stage 1 Increase in SCr ≥26.4 µmol/L or increase to ≥1.5-2.0-fold from baseline <0.5 mL/kg/h for >6 h

Stage 2 Increase in SCr to >2.0-3.0-fold_{from baseline} <0.5 mL/kg/h for >12 h

Stage 3

Increase in SCr to ≥3-fold or SCr ≥354 µmol/L

with an acute rise >44 µmol/L or initiation of RRT

<0.3 mL/kg/h for >24 h or anuria ≥12 h

Serum Creatinine



Gold standard, but far from ideal

•

•

– Protein intake

– Muscle mass

– Age

– Race

– Sex

•

– As much as 50% of kidney function can be lost in that

11

Creatinina Serica

 AKI es actualmente diagnosticado utilizando la creatinina serica

 Indicador no confiable durante cambios agudos

– Concentraciones podrian no cambiar hasta una

reduccion del 50% de la funcion renal

– No refleja de forma aguda la funcion renal hasta que se

alcanza un estado de estabilidad (puede tomar hasta 48 hrs)

– El daño renal ocurre durante el retraso en el

diagnostico

 Util marcador para estimar la GFR

 Pobre valor en el periodo postquirurgico

 El retraso en el diagnostico previene el optimo

traamiento de AKI Bellomo R, et al. Intensive Care Med. 2004;30:33-37. Nguyen MT, et al. Pediatr Nephrol. 2008;23:2151-2157. Star RA. Kidney International. 1998;54:1817-1831.

12

Adapted from Moran SM, Myers BD. Kidney International. 1985;27:928-937

GFR (mL/min)

Serum Creatinine (SCr) (mg/dL)

Creatininina no es el Biomarcador Ideal

0 1 2 3 4 5 6 7 0 20 40 60 80 100

120 _{Surgery, MI, sepsis}

Reversal of ischemia

0 7 14 21 28

Urine Output



May be misleading

Legrand M and Payen D. Ann Intensive Care. 2011;1:13.

•

•

urine output do not necessarily imply decreased GFR.

– Can represent a physiological

renal adaptation for homeostasis

BIOMARKER NEEDS

AKI Biomarkers

MOST AKI MARKERS ARE NOT FDA APPROVED

AND AVAILABLE ONES DO NOT MEET CURRENT CLINICAL NEEDS.

Possible Utility of New Biomarkers



Early detection



Differential diagnosis



Prognosis

– Predict need for dialysis

– Reversibility

Unmet Clinical Needs



AKI is difficult to assess.



Mortality is high and it carries a very

high cost.



Currently available methodologies

and biomarkers are not meeting

clinical needs.



New biomarkers are on the horizon

Biomarcadores de Daño Renal

Clasificacion ADHF

20

Definition and Pathophysiology of Cardiorenal Syndrome Subtypes – HF and AKI

28

Neutrophil Gelatinase Associated Lipocalin

(NGAL), Lipocalin-2, Siderocalin: Physiology

and Clinical Relevance

 Member of the lipocalin superfamily

 Normally expressed at very low levels in kidney, lungs, heart, stomach, and colon

 Increased after injury and ischemia

– One of the most highly induced proteins in kidney after

ischemic or nephrotoxic AKI in animal models

– Highly up-regulated in the distal convoluted tubule during

injury/ischemia, leading to a marked increase of NGAL in the urine

 Protective role

– Murine models of renal ischemia-reperfusion showed

amelioration of morphologic and functional injury when treated with NGAL

 Early diagnostic biomarker for AKI

Devarajan P. Nephrol Dial Transplant. 2008;23:3737-3743. Parikh CR, Devarajan P. Crit Care Med. 2008;36(suppl):S159-S165. Mishra J, et al. J Am Soc Nephrol. 2004;15:3073-3082.

29

Induction of Mouse Kidney NGAL After

Ischemia

25 kD

55 kD

Mishra J, et al. J Am Soc Nephrol. 2003;14:2534-2543.

Unilateral Ischemia Reperfusion Bilateral Ischemia Reperfusion

NGAL Tubulin NGAL Tubulin 25 kD 55 kD

Con 3 hr 12 hr 24 hr Con 3 12 24 48 72 Hours

Con = control

30

Ischemic Kidneys Synthesize Renal NGAL

mRNA

Adapted from Schmidt-Ott KM, et al. J Am Soc Nephrol. 2007;18:407-413.

mRN A L ev els, fo ld chan g e Hours Post-Ischemia *P≤.05 NGAL

FGF2 (basic fibroblast growth factor)

HF (hypoxia-inducible factor)

BMP7 (bone morphogenic protein 7)

0 10 20 30 40 50 * * * * 1000 100 10 1 0.1 0.01 * * * * * * * * * * * *

31

Function of NGAL



Role in kidney development

– Promotes epithelial differentiation by

targeting a stromal/intestinal/progenitor niche at the periphery of the developing kidney

– Affects the structure of established epithelia



Binds labile iron in cytosol and

pericellular space



Iron-associated NGAL regulates

iron-responsive genes (ferritin, transferrin

receptor)

Devarajan P. Nephrol Dial Transplant. 2008;23:3737-3743. Schmidt-Ott KM, et al. J Am Soc Nephrol. 2007;18:407-413.

NGAL

Hydroxyl radical = OH.Hydroxide anion; = OH- ; oxygen = O

2 ; superoxide anion = . _O 2

-ACS

AKI

Oxidative Stress Reactions

OH

-H₂O

+ +

Percent

N>100,000 patients

Slide courtesy of Christopher De Filippi

Prevalence of Renal Dysfunction in Patients

with AHF

• Renal dysfunction is a likely element of pathophysiology of

heart failure and highly prevalent as demonstrated in findings from the ADHERE database.

34

NGAL for the Diagnosis of AKI in the

Emergency Department

Nickolas TL, et al. Ann Intern Med. 2008;148:810-819. N = 635 0 250 500 750 1000 1250 1500 * * * * _* * AKI Prerenal Azotemia CKD Normal Kidney Function U ri n e N GA L , μ g /g 0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00 18.00 20.00 * * * * * * * * * AKI Prerenal Azotemia CKD Normal Kidney Function Pr esen ti n g Ser u m C reati n in e, mg /d L

35

Meta-Analysis: Accuracy of NGAL in AKI

 Meta-analysis of 19

diagnostic studies (2538 patients)

 NGAL was a valuable

and early predictor of AKI, both overall and across a diverse

range of clinical settings

 The cutoff NGAL

value for optimum sensitivity and

specificity across all settings was >100 ng/mL  A more consistent cutoff value of >150 ng/mL was identified when using standardized

platforms Haase M, et al. Am J Kidney Dis. 2009;54:1012-1024.

Setting Specificity AUC-ROC

Diagnostic Odds Ratio

AKI across settings 85.1 0.815 18.6

AKI after cardiac surgery 75.1 0.775 13.1

AKI in critically ill patients 75.5 0.728 10.0

AKI after contrast infusion 96.3 0.894 92.0

AKI prediction using

serum NGAL 86.6 0.775 17.9 AKI prediction using

urine NGAL 84.3 0.837 18.6

Cardiorenal Syndrome Type 1: Creatinine

Increase in Acute HF Patients.

Gottlieb SS et al. J Card Fail. 2002;8:136. Smith G, J Card Fail. 2003 Feb;9(1):13-25

X X X X X X X X X X X X X X X 0.5 0.4 0.3 0.2 0.1 0 20 40 60 80 100 1 3 5 7 9 11 13 15 Days % Cr

Small increases in Cr are associated with poor outcomes and occur in 30% of patients

hospitalized for HF

NO. OF PATIENTS

REFERENCE TP FP FN TN NGAL CUTOFF (NG/ML)

SENSITIVITY (%; 95% CI) SPECIFICITY (%; 95% CI)

Mishra et al, 2005 (p) 14 3 6 48 > 25 70.0 (45.7-87.2) 94.1 (82.8-98.5) Mishra et al, 2005 (u) 20 1 0 50 > 50 100.0 (80.0-100.0) 98.0 (88.2-99.9) Wagener et al, 2006 11 23 5 42 > 400 68.8 (41.5-87.9) 64.6 (51.7-75.8) Dent et al, 2007 38 5 7 73 > 150 84.4 (69.9-93.0) 93.6 (85.0-97.6) Zappitelli et al, 2007 12 7 4 16 > 10 75.0 (47.4-91.7) 69.6 (47.0-85.9) Hirsch et al, 2007 (p) 8 1 3 79 >100 72.7 (39.3-92.7) 98.8 (92.3-99.9) Hirsch et al, 2007 (u) 8 0 3 80 > 100 72.7 (39.3-92.7) 100.0 (94.3-100.0) Wagener et al, 2008 44 172 24 186 > 450 64.7 (52.1-75.6) 52.0 (46.7-57.2) Bennett et al, 2008 78 8 21 89 >150 78.8 (69.2-86.1) 91.8 (83.9-96.1) Ling et al, 2008 10 8 3 19 -- 76.9 (46.0-93.8) 70.4 (49.7-85.5) Koyner et al, 2008 (p) 8 13 10 41 > 280 44.4 (22.4-68.7) 75.9 (62.1-86.1) Koyner et al, 2008 (u) 12 19 6 35 > 550 66.7 (41.2-85.6) 64.8 (50.6-77.0) Nickolas et al, 2008 20 16 3 502 > 80 87.0 (65.3-96.6) 96.9 (94.9-98.2) Lima et al, 2008 5 12 1 34 -- 83.3 (36.5-99.1) 73.9 (58.6-85.3) Wheeler et al, 2008 19 74 3 47 > 140 86.4 (64.0-96.4) 38.8 (30.3-48.2) Xin et al, 2008 2 8 1 22 > 250 66.7 (12.5-98.2) 73.3 (53.8-87.0) Cruz et al, 2009 47 46 17 191 > 150 73.4 (60.7-83.3) 80.6 (74.9-85.3) Makris et al, 2009 (CIN) 5 6 1 44 60 90.0 (54.1-99.5) 88.0 (75.0-95.0) Makris et al, 2009 (ICU) 6 7 1 17 > 190 85.7 (42.0-99.3) 70.8 (48.8-86.6) Constantin et al, 2009 43 1 9 35 > 155 82.7 (69.2-91.3) 97.2 (83.8-99.9) Tuladhar et al, 2009 (p) 7 13 2 28 > 420 77.8 (40.2-96.1) 68.3 (51.8-81.4) Tuladhar et al, 2009 (u) 8 9 1 32 > 390 88.9 (50.7-99.4) 78.1 (62.0-88.9) Haase-Fielitz et al, 2009 18 17 5 60 > 150 78.3 (55.8-91.7) 77.9 (66.8-86.3)

Sensitivity and Specificity of Studies for NGAL to Predict AKI

Discusión

3.METODOS DE MEDIDA DE UNGAL

• Los diferentes métodos existentes son inmunoensayos (reacciones

antígeno-anticuerpo)

• Dependiendo de las secuencias del antígeno (uNGAL) que reconocen los anticuerpos utilizados, las concentraciones de uNGAL pueden variar

significativamente método a método

Discusión

4. Isoformas de NGAL en orina

ORIGEN DEL uNGAL

-Epitelio renal: DRA -Neutrófilos infiltrando epitelio renal: DRA -:Neutrófilos activados: Infección tracto urinario (ITU) -Tejidos extrarrenales MONOMÉRICO (25 KDa) HOMODIMÉRICO (50 KDa) HETERODIMÉRICO (135 KDa) DRA ITU DRA

A Rigorous Discovery-Validation Path

Was Taken

44

Discovery Study 340 proteins analyzed (including KIM-1, urine

NGAL, plasma NGAL, Cystatin-C, IL-18, pi-GST,

and L-FABP)

Validation Study Primary Endpoint: moderate to severe AKI (KDIGO stage 2-3) within

12 hours of sample collection

(based on serum creatinine and hourly

urine output)

Sapphire Study 35 sites

(20 North America, 15 Europe) Age > 21, Critically Ill3,

no AKI (Stage 2 or 3)4 N = 744 Vienna Cohort Age > 18, in ICU + Sepsis N = 134 Duke Cohort Age > 18, At least 1 risk factor1

N = 123

Mayo Cohort Age > 18, At least 1 risk factor2

N = 265 N = 7285 No AKI N = 416 AKI Stage 1 N = 211 AKI Stage 2 N = 83 AKI Stage 3 N = 18 16 patients excluded (2 withdrew consent, 7 lost to follow-up, 7 with

invalid or missing test results)

Best Two Markers

D is co v er y V a li d a ti o n Within 12 hrs

Revolutionary Biomarkers Were Identified

 Biomarkers identified through hypotheses based on AKI pathophysiology

 340 candidate biomarkers identified

 Biomarkers ranked by ability to predict

development of AKI RIFLE I or F within 12 to 36 hours

 All possible combinations of two-four biomarkers (novel or previously described) were ranked

 Top performing biomarkers identified

– Tissue Inhibitor of Metalloproteinases-2 (TIMP-2)

– Insulin-like Growth Factor Binding-Protein 7 (IGFBP7)

45

TIMP-2 and IGFBP7 Outperform Existing

Biomarkers

AUC for [TIMP-2]•[IGFBP7] was significantly greater than any existing

biomarkers ₄₆

47

TIMP-2 and IGFBP7 Work Well In

Important Subgroups

Sepsis

Surgery

[TIMP-2]•[IGFBP7] Has a Compelling

Specificity Profile

48

Urine NGAL (ng/mL) [TIMP-2]•[IGFBP7] ((ng/mL)2 _{/ 1000)}

[TIMP-2]•[IGFBP7] Has a

Compelling Specificity Profile

49

Urine KIM-1 (ng/mL) [TIMP-2]•[IGFBP7] ((ng/mL)2 _{/ 1000)}

TIMP-2 and IGFBP7 Have Compelling Mechanistic Origins in Early Cellular Injury

50

Proposed mechanism

IGFBP7 & TIMP-2 are markers of G1 cell cycle arrest during early cell injury Renal tubular cells enter a short

period of G1 cell-cycle arrest following injury G1 cell-cycle arrest presumably prevents the cells from dividing when the DNA may be damaged IGFBP7 & TIMP-2 may also signal in

autocrine and paracrine fashions, spreading ‘alarm’ from the site of injury

These processes and marker signals occur early enough in injury to take action

TIMP-2 and IGFBP7 Remain Highly

Significant In Clinical Models With Risk

Factors

APACHE III Score 0.35 0.067

Hypertension 0.004 0.013

Nephrotoxic drugs 0.12 0.013

Liver Disease 0.069 0.057

Sepsis 0.32 0.64

Diabetes 0.29 0.35

Chronic Kidney Disease 0.27 0.64

Serum Creatinine <0.0001 <0.0001

C-stat (AUC) 0.87 0.87

Endpoint was KDIGO 2-3 (RIFLE I/F) within 12 hours. All clinical risk factors with univariate p-value ≤ 0.1 for predicting the endpoint were included in the models. Net reclassification and integrated discrimination improvement analyses were also performed and showed significant enhancement of the models by [TIMP-2][IGFBP7].

Key Messages

 Both IGFBP7 and TIMP-2 are inducers of G1 cell cycle arrest, a key mechanism implicated in AKI

 IGFBP7 and TIMP-2 are new biomarkers for AKI and

perform better than existing biomarkers for predicting the development of moderate or severe AKI (KDIGO stage 2 or 3) within 12 hours of sample collection

 [TIMP-2]•[IGFBP7] significantly improved risk

stratification when analyzed using Cox proportional hazards model, generalized estimating equation,

integrated discrimination improvement or net reclassification improvement

 Risk for major adverse kidney events within 30 days (MAKE₃₀) elevated sharply above [TIMP-2]•[IGFBP7]

values > 0.3 and doubled when [TIMP-2]•[IGFBP7] values

were > 2.0 ₅₂

The NEPHROCHECK® Test System



The NEPHROCHECK® Test quantitatively

measures two urinary biomarkers

--tissue inhibitor of metalloproteinase 2

(TIMP-2) and insulin-like growth factor

binding protein 7 (IGFBP-7), which are

thought to be involved in G1 cell cycle

arrest in the earliest phases of inju

The NEPHROCHECK® Test System

MediBeacon has created a research grade technique that is clinically applicable for real-time point-of-care Glomerular Filtration Rate measurement (mGFR). MediBeacon has invented a fluorescent tracer agent (MB-102) that is removed from the blood exclusively by the GFR mechanism of the kidneys.

57

Conclusiones

 Sìndrome Cardio-Renal

 Se requieren predictores tempranos, confiables y exactos de daño renal agudo Biomarcadores.

 NGAL POCT

 IGFBP7 and TIMP-2 POCT

59

Cystatina C



Inhibidor proteasa Cysteina

– Sintetizada y liberada dentro de la sangre en rangos constantes por todas las celulas

nucleadas



Cuantificación GFR

– Sus niveles sanguineos no se afectan po rla edad, genero, raza o desarrollo muscular

– Ventajas en los niños, ancioanos, UCI y paciente de alto riesgo (diabetes)

– Detecta camibios ligeros en la funcion renal



Incremento mas temprano que la creatinina

en AKI

Nguyen MT, et al. Pediatr Nephrol. 2008;23:2151-2157. Koyner JL, et al. Kidney Int. 2008;74:1059-1069. Herget-Rosenthal S, et al. Kidney Int. 2004;66:1115-1122.

60

Interleukin-18 (IL-18)

 Citokina proinflamatoria

 Inducida y liberada en le tubulo proximal y se detecta en la urina siguiendo AKI isquemico

– Detección 4–6 hours post-cardiopulmonary bypass

– Deteccíon UCI 48 horas antes de AKI

 Marcador predictivo temprano de AKI y mortalidad

– Predice desarrollo de AKI 24 horas antes que la creatinina

serica

 Puede diferenciar entre necrosis tubular aguda y otros tipos de enfermedad aguda renal

 No predice AKI mas rapido que NGAL urinario

 Puede ser influenciado por otras variables y estados fisiopatologicos.

Parikh CR, et al. J Am Soc Nephrol. 2005;16:3046-3052. Coca SG, et al. Kidney International. 2008;73:1008-1016. Devarajan P. Expert Opin Med Diagn. 2008;2:387-398.

61

Kidney Injury Molecule 1 (KIM-1)

 Proteina de transmembrana, altamente

sobreexpresada en celulas del tubulo proximal despues de AKI isquemico o nefrotoxico

 Bueno para evaluar el diagnostico de AKI

– No es solido para facilitar el diagnostico temprano

 KIM-1 urinario distingue AKI isquemico de azoemia prerenal y CKD

 Puede predecir los desenlaces adeversos y se

asocia con medidas de severidad de la enfermedad

– Predice el riesgo de mortalidad despues de AKI



Muy especifico en daño isquemico o

nefrotoxico, pero no es sensible en estadios

tempranos

Coca SG, et al. Kidney International. 2008;73:1008-1016. Parikh CR, et al. J Am Soc Nephrol. 2005;16:3046-3052. Devarajan P. Expert Opin Med Diagn. 2008;2:387-398.